Sample records for lake pupuke auckland

  1. Late Holocene climate variability from Lake Pupuke maar, Auckland, New Zealand

    NASA Astrophysics Data System (ADS)

    Striewski, B.; Shulmeister, J.; Augustinus, P. C.; Soderholm, J.

    2013-10-01

    Spectral analyses of quasi-annual organo-diatomaceous laminae couplets in an Auckland maar lake indicate brief (sub-decadal scale) episodes with strong spectral power and long periods of weak to no spectral power between c. 1700 to c. 550 cal. yr BP. Laminae couplet thickness appears to be a function of changes in wind flow over the basin, with enhanced wind flow deepening the mixing zone and providing additional nutrients for laminae formation. Aeolian dust from Australia amplifies the wind signal. Spectral signals in the high power episodes are focused in <4 years and 6-8 years windows. These are consistent with El Niño-Southern Oscillation (ENSO) periodicity. This climate system is known to play a major role in the modern Auckland climate whereby strongly negative (positive) ENSO are associated with enhanced (diminished) SW airflow over Auckland. ENSO events interact in the modern climate and the spectral results indicate that this is the case when spectral power is strong in the laminae. These results highlight strong but intermittent ENSO activity between 600 and 1400 cal. yr BP.

  2. Postglacial Records of Southern Hemisphere Westerly Wind Variability From the New Zealand Subantarctic Auckland Islands

    NASA Astrophysics Data System (ADS)

    Moy, C. M.; Vandergoes, M.; Gilmer, G. J.; Nichols, J. E.; Dagg, B. J.; Wilson, G. S.; Browne, I. M.; Curtin, L. G.; Aebig, C.; McGlone, M.

    2015-12-01

    The strength and latitudinal position of the Southern Hemisphere westerly winds (SHWW) play a fundamental role in influencing mid latitude climate and carbon dioxide exchange between the Southern Ocean and the atmosphere. Despite their importance, our understanding of past changes in the SHWW is limited by few paleoclimate records from the modern wind maximum that are often not in agreement. The New Zealand subantarctic Auckland Islands are located within the core of the modern wind belt (50°S) where the ocean-atmospheric linkages between the Antarctic and middle latitudes are strong. In contrast to other subantarctic islands on the Campbell Plateau, the Auckland Islands have protected fjord sub-basins, deep lakes, and peatlands that are advantageous for the development of high-resolution paleoclimate records. We will present ongoing work towards the establishment of multi-proxy and multi-site reconstructions of past SHWW variability from the Auckland Islands. Modern process and paleoclimate results from two research cruises in 2014 and 2015 suggest that in lacustrine and fjord settings, the degree of water column mixing, the stable isotopic composition of n-alkanes and benthic foraminifera, the influx of terrestrial organic matter are good indicators of wind-induced mixing of the water column or precipitation-driven erosion within catchments. In ombrotrophic peatlands, hydrogen isotope ratios of specific organic molecules allow reconstructions of the hydrogen isotope ratios of precipitation, which is related to precipitation source area and the latitudinal position of the SHWW. Using macrofossil counts paired with abundances of leaf wax biomarkers, we are able to estimate the moisture balance at peatland coring sites. Early results indicate an overall strengthening of the SHWW at the Auckland Islands through the Holocene. We will discuss these results within the context of complimentary records developed from New Zealand and southern South America to ultimately

  3. Auckland--New Zealand's Los Angeles or San Francisco?

    ERIC Educational Resources Information Center

    Bogunovich, Dushko

    1995-01-01

    Compares Auckland (New Zealand) with San Francisco (California) in terms of topographical structure, geographic location, and urban development. Both cities contain striking similarities. Maintains that Auckland can become a world-class city renowned for its beauty if developers and government work in tandem. (MJP)

  4. A Multiproxy Reconstruction of Holocene Southern Westerlies from the Auckland Islands

    NASA Astrophysics Data System (ADS)

    Nichols, J. E.; Moy, C. M.; Peteet, D. M.; Weiss, A.; Curtin, L. G.

    2015-12-01

    The strength and position of the Southern Hemisphere Westerly Wind belt plays an important role in our understanding of the global carbon cycle and glacial-interglacial climate change. We present a paleoclimate record that is primarily influenced by the strength and latitudinal position of the Southern Hemisphere Westerly Winds from a late Holocene lake sediment core and a peat core that spans the last 13,000 years, both obtained from New Zealand's subantarctic Auckland Islands (50°S, 166°E). Several proxy indicators contribute to our reconstruction. Hydrogen isotope ratios of specific organic molecules allow us to reconstruct the hydrogen isotope ratios of precipitation. Using macrofossil counts and the abundances of leaf wax biomarkers, we are able to estimate the moisture balance at our sites. Model simulations of the Westerlies and the rate and isotope ratios of precipitation allow us to interpret our proxy data as changes in the strength and position of the Westerly Winds. In our lacustrine sediment, we found that the Westerlies have been shifting southward since the Little Ice Age, consistent with modern observations of a southward shift. In the peatland sediment, we found a multi-millennial northward shift in the Westerlies during the middle Holocene. We will present further ongoing work that strengthens the chronology of Auckland Islands environmental change and integrates these results with vegetation shifts identified in pollen and macrofossil data.

  5. Auckland regional emergency medicine trainee mentoring uptake survey.

    PubMed

    Nicholls, Gordon Michael Mike; Lawrey, Emma; Jones, Peter

    2017-10-01

    The primary objective of this study is to quantify how many Auckland region emergency medicine (EM) trainees would like a formal mentoring programme. The secondary objectives were to quantify how many Auckland region EM trainees would like to participate in a formal mentoring programme; to determine trainees' current understanding of mentoring; how trainees prefer mentors to be allocated; why trainees may want a mentor; what mentees perceive would be good qualities in a mentor; and trainees' prior experience with mentoring. Online survey of EM trainees in the Auckland region in June 2015. Of 61 potential respondents, 40 (65.6%) respondents replied to the survey. Of the 40, 38 (95%; 95% confidence interval (CI) 82.6-99.5) respondents indicated they would like some form of mentoring system, and of the 38, 25 (65.8%; 95% CI 49.8-78.9) preferred this to be formal. Of the 38, 19 (50%; 95% CI 34.9-65.2) currently wanted assistance obtaining a mentor. Of the 40, 30 (75%; 95% CI 59.6-86.0) are not currently in any form of mentoring relationship. Respondents believed that mentors would be most beneficial in critical incidents, career development and with work/life balance. The attributes participants considered most important in a mentor were respecting confidentiality, being honest and the ability to provide constructive feedback. Many EM trainees in Auckland want a formal mentoring system and would like a mentor. Appropriate mentor-mentee matching through a formalised voluntary system, with adequate mentor training, may enable the Auckland region to develop a suitable mentoring programme for EM trainees. © 2017 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

  6. Imported malaria in Auckland, New Zealand.

    PubMed

    Camburn, Anna E; Ingram, R Joan H; Holland, David; Read, Kerry; Taylor, Susan

    2012-11-09

    To describe the current malaria situation in Auckland, New Zealand. We collected data on all cases of malaria diagnosed in Auckland from 1st October 2008 to 30th September 2009. Enhanced surveillance was arranged with all hospital and community haematology laboratories in the region. Laboratories notified us when a diagnosis of malaria was made. After obtaining informed consent the patient was asked about their travel, prophylaxis taken and symptoms. Laboratory results were collected. There were 36 cases of malaria in 34 patients. Consent could not be obtained from two patients so data is from 34 cases in 32 patients. (One patient had P.falciparum then later P.vivax, the other had P.vivax and relapsed.) There were 24 males and 8 females with a median age of 21 years (range 6 months to 75 years). Eleven of the 32 were New Zealand residents. 8 of these 11 had travelled to visit friends or relatives (VFR) while 3 were missionaries. In this group 6 had P.falciparum, 4 P.vivax and one had both. Twenty-one of the 32 were new arrivals to New Zealand: 11 refugees and 10 migrants. Malaria in Auckland is seen in new arrivals and VFR travellers, not in tourist travellers.

  7. Auckland: city of syphilis?

    PubMed

    Azariah, Sunita

    2016-12-16

    To briefly report on the large increase in cases of syphilis managed at Auckland Regional Sexual Health Service (ARSHS) in 2015. To raise awareness of syphilis as an emerging significant public health issue in Auckland. A search was conducted of the electronic patient management system at ARSHS for cases of syphilis diagnosed between 1st of January 2015 and 31st of December 2015. Those that fitted the Institute of Environmental Science and Research Ltd (ESR) case definitions for infectious syphilis were included and demographic, clinical and behavioural characteristics were described. One hundred and fifty-two cases of infectious syphilis were managed at ARSHS in 2015, which was a 78% increase from the previous year. The crude incidence rate was 9.5 cases per 100,000 head of population. As in previous years, the majority of cases were male (92%) and most of these were gay or bisexual men (GBM). Thirty-nine percent of cases were asymptomatic and 22% of cases were diagnosed with another STI. Twenty-eight percent of GBM were co-infected with HIV. While the overall number of heterosexual cases was small (n=35); there was a 3.8-fold increase from the numbers diagnosed in 2014 (n=9). The largest number of syphilis cases in recent decades was managed by the Auckland Regional Sexual Health Service in 2015. The increase in numbers is concerning as syphilis can enhance transmission and acquisition of HIV. Furthermore, other countries have noted increases in congenital syphilis cases when incidence in females has increased. It is important that all persons at risk of STI are tested for syphilis and that sexually active GBM in particular are tested regularly. Health professionals need to be made aware of who and when to test, and to refer or discuss any suspected cases with a specialist service as management of syphilis requires significant expertise.

  8. Antimicrobial consumption at Auckland City Hospital: 2006-2009.

    PubMed

    Ticehurst, Rob; Thomast, Mark

    2011-04-15

    We aimed to determine the level of antimicrobial consumption by adult inpatients at Auckland City Hospital (Auckland, New Zealand) and to compare our findings with those in other developed nations. We used the computerised records of the central Auckland District Health Board (ADHB) pharmacy to measure the amount of antimicrobials dispensed to inpatients (excluding psychiatric units, day stay units and outpatient clinics) during 2006 to 2009. The total weight of each antimicrobial dispensed was used to determine the number of defined daily doses (DDDs) dispensed. The Information Management and Technical Services department of ADHB provided data on the number of admissions and inpatient days, and these data, together with information from the 2006 census, were used to calculate antimicrobial consumption for adult inpatients measured in DDDs/100 admissions, DDDs/100 inpatient days and DDDs/1000 population. Total antimicrobial consumption by adult inpatients increased from 74 DDDs/100 inpatient days in 2006 to 80.3 DDDs/100 inpatient days in 2009. The level of consumption did not vary greatly with the season. The total level of consumption was very similar to that seen in adult inpatients in hospitals in Australia and Scandinavian countries. The level of consumption of fluoroquinolones, third or fourth generation cephalosporins, carbapenems and vancomycin (antimicrobial classes that are not available for unrestricted use in Auckland City Hospital) was comparable to or less than that seen in adult inpatients in hospitals in Australia or Scandinavian countries. Beta-lactamase susceptible penicillins (such as benzyl penicillin and phenoxymethylpenicillin) comprised a relatively small proportion of total penicillin use and beta-lactamase inhibitor combinations (predominantly amoxicillin/clavulanate) a relatively large proportion of total penicillin use, when compared with Scandinavian hospitals. The antimicrobial stewardship programme at Auckland City Hospital has

  9. Symptom presentations and other characteristics of colorectal cancer patients and the diagnostic performance of the Auckland Regional Grading Criteria for Suspected Colorectal Cancer in the South Auckland population.

    PubMed

    Hsiang, John C; Bai, Wayne; Lal, Dinesh

    2013-09-13

    This study reviews the presenting symptoms of colorectal cancer in the ethnically diverse Middlemore Hospital referral population of South Auckland, New Zealand. The performance of the newly introduced Auckland Regional Grading Criteria as prediction tool for selecting colorectal cancer cases referred from primary care was evaluated in this group. Retrospective review of all colorectal cancer (CRC) cases diagnosed between January 2006 and January 2011. Information extracted from case note review was used to grade patients using the Auckland Regional Grading Criteria. A total of 799 patients were included. The commonest symptoms were: rectal bleeding (25.5-42.3%) and change in bowel habit (20.6-26.8%). Low-risk symptoms including abdominal pain (16.3-46.8%) and weight loss (18.4-26.1%) were not uncommon. 64.4% of Maori and 64.9% of Pacific patients had stage III or IV cancers. Pacific patients had more stage IV disease, 37.7% (p<0.001) and were less likely to undergo tumour resection, 26.0% (p<0.001). The Auckland Regional Grading Criteria would miss 24.7% of the patients with CRC in the referral population. While rectal bleeding and change in bowel habit are frequent presenting symptoms, low-risk atypical symptoms including constipation, weight loss and abdominal pain were not uncommon. Significant proportion of Pacific patients present with late-stage disease. The current Auckland Regional grading criteria would miss significant proportion of our study population with colorectal cancer.

  10. Climate and respiratory disease in Auckland, New Zealand.

    PubMed

    Gosai, Ashmita; Salinger, James; Dirks, Kim

    2009-12-01

    Increases in the incidence of diseases are often observed during the cold winter months, particularly in cities in temperate climates. The study aim is to describe daily, monthly and seasonal trends in respiratory hospital admissions with climate in Auckland, New Zealand. Daily hospital admissions for total respiratory infections or inflammations (RII), total bronchitis and asthma (BA), and total whooping cough and acute bronchitis (TWCAB) for various age groups and ethnicities were obtained for the Auckland Region and compared with climate parameters on daily, monthly and seasonal time scales. Seasonal and monthly relationships with minimum temperature were very strong (p<0.001) for RII over all age groups, for BA in the older age groups (14-64, 65+) and for TWCAB in the <1 year old age group. European, NZ Māori and Pacific Islanders all showed increases in admissions as temperatures decreased. Pacific Islanders were particularly susceptible to RII. There was a lag in admissions of three to seven days after a temperature event. Results show that increases in respiratory admissions are strongly linked to minimum temperatures during winter, typical of cities with temperate climates and poorly-insulated houses. There are implications for hospital bed and staffing planning in Auckland hospitals.

  11. Tuberculosis in Auckland autopsies, revisited.

    PubMed

    Lum, Dennis; Koelmeyer, Timothy

    2005-03-11

    To review the cases of tuberculosis found at autopsy in the Auckland Coronial Autopsy Service in the previous 10 years, and compare the results with that of a similar study for the period 1975 to 1992. Cases which were not diagnosed prior to autopsy are scrutinised as to why the diagnosis may have been missed. A computerised search of the Forensic Pathology Department database at Auckland Hospital for cases of tuberculosis or atypical mycobacterial infection found at autopsy was done. Basic demographic data, past medical history, and police reports were analysed. The cases were placed into five groups for analysis. A total of 30 cases of tuberculosis (including 3 cases of atypical mycobacterial infection) were found. A large proportion (70%) was undiagnosed before death, and each case was potentially infective. Two cases had respiratory symptoms suggestive of tuberculosis, and a further 5 cases had generalised symptoms which were unexplained yet tuberculosis was not considered. In those cases that were missed, the autopsy played a vital role by identifying the previously undiagnosed cases of tuberculosis and ensuring contact screening. Awareness of tuberculosis and its increasing prevalence in New Zealand is essential for minimising missed diagnoses.

  12. Postglacial Records of Southern Hemisphere Climate and Oceanographic Change From the New Zealand Subantarctic Auckland Islands

    NASA Astrophysics Data System (ADS)

    Moy, C. M.; Gilmer, G.; Nichols, J. E.; Browne, I. M.; Curtin, L.; Vandergoes, M.; Aebig, C.; Wilson, G. S.

    2017-12-01

    The strength and latitudinal position of the Southern Hemisphere westerly winds (SHWW) play a fundamental role in influencing mid-latitude climate and CO2 exchange between the Southern Ocean and the atmosphere along seasonal to glaicial-interglacial timescales. Despite their importance, our understanding of past SHWW change is limited by the small number of paleoclimate records from the modern wind maximum, which are often not in agreement. The New Zealand subantarctic Auckland Islands are located within the core of the modern wind belt (50°S), a key latitude where ocean-atmospheric linkages between the Antarctic and mid-latitudes are strong. In contrast to other subantarctic islands on the Campbell Plateau, the Auckland Islands have multiple protected fjord sub-basins, deep lakes, and peatlands that are advantageous for the development of high-resolution paleoclimate records. We will present ongoing work towards the establishment of multi-proxy and multi-site reconstructions of past SHWW variability from the Auckland Islands. Modern process and paleoclimate studies suggest that in lacustrine and fjord settings, the degree of water column mixing, the stable isotopic composition of n-alkanes and benthic foraminifera, and the influx of terrestrial organic matter are good indicators of wind-induced mixing of the water column or precipitation-driven erosion within catchments. During the Late Glacial and early Holocene (15 to 9 ka), elevated long-chain n-alkane δD values from ombrotrophic peatlands and an increase in the concentration of redox-sensitive elements in fjord sediment cores, signal weakening of the SHWW that appears to be coincident with periods of rapid deglacial warming of West Antarctica. Since 5.5 ka, we interpret declining n-alkane δD values to indicate enhanced westerly flow. These interpretations are in broad agreement with terrestrial paleoclimate records developed from southern South America and argue for a symmetrical response of the SHWW during

  13. The burden of non-melanoma skin cancers in Auckland, New Zealand.

    PubMed

    Pondicherry, Ashwini; Martin, Richard; Meredith, Ineke; Rolfe, Jack; Emanuel, Patrick; Elwood, Mark

    2018-01-19

    As the New Zealand Cancer Registry does not require mandatory reporting of non-melanoma skin cancers (NMSC), basal cell carcinomas (BCC) and squamous cell carcinomas (SCC), the clinical burden of these diseases is unknown. A retrospective review of all patients with histopathology performed allowed us to estimate invasive BCC and SCC in the Auckland region in 2008 (population 1.44 million). During this period, a total of 21 236 NMSC were diagnosed among 13 996 patients, consisting of 5611 SCC lesions (26%) and 15 525 (74%) BCC. The Auckland incidence rates per 100 000 were 425 for SCC and 1177 for BCC. The overall rate of NMSC per 100 000 was 1906.5 (standardised to the census data of Australia 2001); 1385 for BCC and 522 for SCC. Using published data on incidence trends and population growth, we estimate that 29 000-33 000 NMSC would have been excised in Auckland in 2016, and 78 000-87 000 in New Zealand. Auckland has the highest reported incidence of invasive NMSC in the world. We believe that high-risk cutaneous SCC and complex BCC should be recorded. Our study provides information for clinicians and health economists on the scale of the problem. © 2018 The Australasian College of Dermatologists.

  14. Sequential eruption of alkaline and sub-alkaline magmas from a small monogenetic volcano in the Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Needham, A. J.; Lindsay, J. M.; Smith, I. E. M.; Augustinus, P.; Shane, P. A.

    2011-04-01

    Rangitoto Volcano is the youngest and largest eruptive centre in the monogenetic intraplate Auckland Volcanic Field (AVF). The stratigraphy of Rangitoto pyroclastic deposits that have been preserved in swamps on nearby Motutapu Island and in Lake Pupuke on the mainland reveals that the volcano erupted twice; radiocarbon dating of 10 samples from the two tephra units in the swamps indicates eruption ages of 553 ± 7 and 504 ± 5 Cal years BP, for the lower and upper tephra layers, respectively. Geochemistry of the lava field and various scoria cones on Rangitoto Island itself reveals two distinct compositional groups: an alkaline olivine basalt group (that correlates geochemically with the lower tephra layer) and a group that is sub-alkaline and transitional to tholeiite (that correlates geochemically with the upper tephra layer). Based on this data, we infer that, following a phreatomagmatic vent-clearing phase, the early magmatic eruption of Rangitoto Volcano was Strombolian in character and produced an alkaline olivine basalt scoria cone and an associated thick ash deposit on nearby Motutapu Island. This was followed by a time gap of up to several decades, after which a second eruptive phase built the current summit scoria cone together with an encircling lava field. We suggest this later, sub-alkaline eruptive period was associated with the deposition of the thin upper tephra layer on Motutapu Island. The two suites of Rangitoto samples are chemically quite distinct, and each is associated with a distinct parental composition. Trace element modelling indicates the alkaline and sub-alkaline parental melts could have been derived by ~ 1 and 6 wt.% partial melting of an anhydrous garnet peridotite source at ~ 80 and 65 km depth, respectively. The compositional range within each suite is similar, and can be explained by mainly olivine together with minor clinopyroxene fractionation within a relatively simple conduit system in which mixing and mingling were not

  15. Review of acute symptomatic urolithiasis in Auckland.

    PubMed

    Loeff, Stephanie; Saluja, Manmeet; Rice, Michael

    2018-02-02

    To evaluate the incidence of acute symptomatic urolithiasis in the Auckland region. Associated epidemiological factors and stone characteristics were also studied and compared to previous research conducted in order to analyse trends. All patients that presented acutely with symptomatic urolithiasis to the Auckland District Health Board (AHDB) between July 2014 and June 2015 were studied. Clinical data was obtained from medical records and population data was based on estimates provided by the Ministry of Health. Two-tailed tests and the Pearson Chi-Square tests were used for analysis. Overall, 1,125 patients (1,328 events) presented with an incidence of 85 per 100,000 per year, which was lower than that reported in 2006. The highest incidence was found among the Middle Eastern ethnic subgroup (0.130 %), followed by Māori (0.102%), Asian (0.087%), European (0.084%) and Pacific (0.041%) ethnicity. Males were more likely to be affected than females. Urolithiasis was most common in the fifth decade of life (25%). Forty-seven percent of the study population presented with multiple stones and 64% had recurrent urolithiasis or were 'high risk' stone formers. Distal ureteric stones <5mm were the most common (27%). Urine cultures were positive in 16% of cases. Seven hundred and thirty-nine (57%) were managed with medical management and ureteroscopy was most commonly performed for those who needed surgical intervention. The overall incidence of urolithiasis has decreased compared to previous research conducted in Auckland. This deviation could be attributed to the large influx of Asian immigrants observed in this period of time. A caucasian male, between 40-49 years, with a calculus <5mm in the distal ureter with a history of a previous urolithiasis has the highest chance to present with renal colic.

  16. Molecular epidemiology of group A streptococcus from pharyngeal isolates in Auckland, New Zealand, 2013.

    PubMed

    Williamson, Deborah A; Moreland, Nicole J; Carter, Philip; Upton, Arlo; Morgan, Julie; Proft, Thomas; Lennon, Diana; Baker, Michael G; Dunbar, Rod; Fraser, John D

    2014-01-24

    To describe the molecular epidemiology of emm types associated with circulating pharyngeal group A streptococcus (GAS) isolates in Auckland, New Zealand. GAS isolates were collected over a 10-day period from a community pathology provider in Auckland. PCR analysis and sequencing of the emm gene was performed at the Institute of Environmental Science and Research. A total of 52 emm types were identified from 278 GAS isolates. The three most common emm types were emm1, emm89 and emm12. Overall, the experimental 30-valent GAS M protein vaccine covered 19 / 52 (37%) of emm types in our study. Our study provides baseline data on the circulating pharyngeal GAS emm types in Auckland. Future clinical and molecular surveillance of GAS pharyngitis is essential in the context of ongoing GAS vaccine development.

  17. Optimal likelihood-based matching of volcanic sources and deposits in the Auckland Volcanic Field

    NASA Astrophysics Data System (ADS)

    Kawabata, Emily; Bebbington, Mark S.; Cronin, Shane J.; Wang, Ting

    2016-09-01

    In monogenetic volcanic fields, where each eruption forms a new volcano, focusing and migration of activity over time is a very real possibility. In order for hazard estimates to reflect future, rather than past, behavior, it is vital to assemble as much reliable age data as possible on past eruptions. Multiple swamp/lake records have been extracted from the Auckland Volcanic Field, underlying the 1.4 million-population city of Auckland. We examine here the problem of matching these dated deposits to the volcanoes that produced them. The simplest issue is separation in time, which is handled by simulating prior volcano age sequences from direct dates where known, thinned via ordering constraints between the volcanoes. The subproblem of varying deposition thicknesses (which may be zero) at five locations of known distance and azimuth is quantified using a statistical attenuation model for the volcanic ash thickness. These elements are combined with other constraints, from widespread fingerprinted ash layers that separate eruptions and time-censoring of the records, into a likelihood that was optimized via linear programming. A second linear program was used to optimize over the Monte-Carlo simulated set of prior age profiles to determine the best overall match and consequent volcano age assignments. Considering all 20 matches, and the multiple factors of age, direction, and size/distance simultaneously, results in some non-intuitive assignments which would not be produced by single factor analyses. Compared with earlier work, the results provide better age control on a number of smaller centers such as Little Rangitoto, Otuataua, Taylors Hill, Wiri Mountain, Green Hill, Otara Hill, Hampton Park and Mt Cambria. Spatio-temporal hazard estimates are updated on the basis of the new ordering, which suggest that the scale of the 'flare-up' around 30 ka, while still highly significant, was less than previously thought.

  18. Trauma in Auckland: an overview.

    PubMed

    Streat, S J; Donaldson, M L; Judson, J A

    1987-07-22

    Data are presented on all 569 subjects who, as a result of trauma, either died or were admitted to hospital in Auckland over a four week period. Median age was 23 with an overall 3:2 male:female ratio. Median injury severity score (ISS) was five with 9% of subjects having an ISS of 16 or more (major trauma). Blunt trauma accounted for 84% of all injuries. Life threatening injuries were most commonly to the head, thorax and abdomen while the largest number of less severe injuries were to the extremities. Eight subjects died before admission to hospital and a further six in hospital. Definitive care was given to 98% of patients at Middlemore and Auckland hospitals (including the onsite Princess Mary paediatric facility) but 26% had presented first to other hospitals and 43% of all patients were transferred from one hospital to another. The 561 patients used 6380 hospital days (including 314 intensive care days) and the following services--operating room 63%, orthopaedic ward 45%, plastic surgical ward 17%, paediatric ward 15%, neurosurgical ward 10%, general surgical ward 5%, intensive care 5% and CT scanner 4%. Only one hospital death was judged potentially preventable. This study reveals areas where trauma care could be improved, demonstrates the large amount of hospital resources required to treat trauma and particularly highlights the urgent need for studies into strategies for trauma prevention in New Zealand.

  19. Centennial-to-millennial scale climate change during the last 100,000 years: a Southern Hemisphere perspective

    NASA Astrophysics Data System (ADS)

    van den Bos, Valerie; Rees, Andrew; Newnham, Rewi; Augustinus, Paul

    2017-04-01

    The response of past terrestrial ecosystems to abrupt climate change is central to the debate surrounding the consequences of future climate change. Many centennial-to-millennial scale episodes of rapid change over the past 117,000 years have been reported, notably the Dansgaard-Oeschger events of Greenland and the North Atlantic and Antarctic Isotope Maxima. Best expressed in past climate records from the polar and tropical regions, the timing, amplitude and duration of these changes are variable on a global scale, and it is unclear how the events are generated and transmitted to cause such asynchronous patterns. The southern mid-latitudes form a poorly understood piece of the puzzle. Our Marsden-funded project aims to increase understanding of the New Zealand climate system in relation to global patterns over the last 100 kyr by developing high-resolution climate records from the lake sediments contained within Auckland's maars. These crater lakes are unique, because their sediments are laminated throughout and the sedimentation rate is very high. Additionally, the numerous (>50) volcanic ash layers contained within the sediments act as anchor points in our chronologies. We have adopted a multiproxy approach that combines data from biotic, molecular biomarker isotope and geochemical analyses. The remit of my doctorate is to produce two independent, but complementary, temperature reconstructions from chironomid remains (mean summer temperatures) and pollen (mean annual temperatures) from Lake Pupuke sediments. This approach will eventually help us to address whether abrupt climate change events or changes in seasonality influenced climate and biota over the past 100,000 years in northern New Zealand, and whether these changes were driven by triggers from the North Atlantic, Antarctica or the tropics.

  20. Seasonal variation in the acute presentation of urinary calculi over 8 years in Auckland, New Zealand.

    PubMed

    Lo, Sum Sum; Johnston, Richard; Al Sameraaii, Ahmed; Metcalf, Patricia A; Rice, Michael L; Masters, Jonathan G

    2010-07-01

    Symptom prevalence (retrospective cohort) Level of Evidence 2b. To determine the incidence of acute presentation of urinary calculi (UC) in Auckland, New Zealand, during the period 1999-2007, and whether there was any significant seasonal variation. The details of all UC within the population presenting acutely to public hospitals in Auckland between 1999 and 2007 were collected using clinical coding searches International Classification of Disease 10th revision (Australian Modification) N132 and N20. Climatic variables for the Auckland region were obtained from the National Institute of Water and Atmospheric Research, New Zealand. The mean atmospheric temperature, hours of sunshine and humidity data were calculated monthly for this period. During the study there were 7668 acute presentations of UC in the Auckland region. A Poisson regression model showed that the number of presentations was significantly related to temperature (P < 0.001) and hours of sunshine (P = 0.004) but not humidity (P = 0.14). For each degree increase in temperature the number of presentations increased by 2.8% (95% confidence interval 1.3-4.3%). For each 1-h increase in sunshine, the number of presentations increased by 0.2% (0.06-0.33)%. The acute presentation of UC in Auckland, New Zealand, varies significantly with temperature and hours of sunshine. Humidity was not a significant factor.

  1. Fragility fractures at Auckland City Hospital: we can do better.

    PubMed

    Braatvedt, Geoffrey; Wilkinson, Susan; Scott, Marilyn; Mitchell, Paul; Harris, Roger

    2017-12-01

    This study describes in detail the burden of caring for patients aged ≥ 50 years seen in one year with a fragility fracture in a large urban environment and shows that these fractures result in a long length of stay and significant mortality. Intervention to prevent further fracture was poorly done. To examine the epidemiology of fragility fracture in patients over age 50 years and record the number who received appropriate secondary prevention treatment. All patients aged ≥ 50 years presenting with a fracture during the 12 months following July 1 st 2011, to Auckland City Hospital or residing in central Auckland at the time of their fracture, were identified from hospital and Accident Compensation Corporation records. A random sample of 55% of these patient's records were reviewed to establish the type of fracture, prior fracture and falls history, and use of bisphosphonates in the 12 months before presentation. Their length of stay (LOS) by type of fracture was recorded. The use of bisphosphonate drugs in the following 12 months was obtained from centralised national records of prescriptions. 2729 patients aged ≥ 50 years presented with a fragility fracture in the central Auckland region in one year. Fifty-six percent of these patients were seen at Auckland Hospital and of these, 82% patients required admission with a mean LOS of 20 days (SD ± 24 days).The remaining 44% of patients were looked after in the private outpatient sector. Approximately 30% of the admissions were for hip fracture. Sixty-four percent of patients with a fragility fracture did not receive a potent bisphosphonate, 12% were considered not appropriate for treatment, and 24% received a potent bisphosphonate during their admission or in the next 12 months. Approximately 1 in 18 people aged ≥ 50 years presented in one year with a fragility fracture.Secondary prevention strategies were poorly implemented. Additional resources for identifying and initiating secondary fracture prevention

  2. Living with Volcanoes: Year Eleven Teaching Resource Unit.

    ERIC Educational Resources Information Center

    Le Heron, Kiri; Andrews, Jill; Hooks, Stacey; Larnder, Michele; Le Heron, Richard

    2000-01-01

    Presents a unit on volcanoes and experiences with volcanoes that helps students develop geography skills. Focuses on four volcanoes: (1) Rangitoto Island; (2) Lake Pupuke; (3) Mount Smart; and (4) One Tree Hill. Includes an answer sheet and resources to use with the unit. (CMK)

  3. High acuity GIS comparison of dentist and doctor surgery locations in Auckland, New Zealand.

    PubMed

    Kruger, E; Whyman, R; Tennant, M

    2013-06-01

    New Zealanders are one of the healthiest populations in the world, but significant inequalities in health and oral health remain. New Zealand suffers a possible shortage of medical and dental practitioners and an agreed mal-distribution of both. This study examines the distribution of dental and medical practices in New Zealand's largest city Auckland, using modem Geographic Information System tools. The aim of the study is to determine if medical and dental practices are similarly distributed across the city. The address for each dental and medical practice in Auckland was obtained and mapped over the census population data. A total of 442 medical and 256 dental practices were geo-coded in the study area. These practices overlaid the Auckland region, with a total population of 0.8 million, and an adult population (>9 years old) of 0.69 million. Auckland city was deemed, for this study, to be a region included in a 15km radius circle from a central reference point that was the General Post Office (GPO). The medical practice to total population ratio ranged from 1:1,500 for people 121/2-15km from the GPO, to 1:1,200 for those within 21/2km. Dental practice to population ratio ranged from 1:2,700 for people living 121/2-15km from the GPO to 1:1,300 for those within 21/2km. Medical practices were relatively evenly distributed, regardless of distance from the GPO, but the fairly dense distribution of dental practices in the city's inner 21/2km circle rapidly decreased in density as distance from the GPO increased. These results refute the hypothesis of this study in that there is a similar distribution of primary health practices (medical and dental) across the Auckland region.

  4. Sharing prescription medicines: results of a survey of community pharmacy clients in Auckland, New Zealand.

    PubMed

    Gascoyne, Alexandra; Beyene, Kebede; Stewart, Joanna; Aspden, Trudi; Sheridan, Janie

    2014-12-01

    The practice of medication sharing, the lending (giving) or borrowing (taking) of prescription medicines, has been reported increasingly in the literature. This study aimed to investigate prescription medication sharing practices among adults in Auckland, New Zealand. Community pharmacies in Auckland. A cross-sectional survey was conducted in ten community pharmacies in Auckland during March, 2012. Clients were invited to complete an anonymous questionnaire to assess their medication sharing practices. Proportion of respondents reporting lending or borrowing; information provided or received. Of all participants (N = 642), 25.5% reported borrowing, and 24.1% reported lending prescribed medicines in the past year. Furthermore, 14.8% of participants reported ever giving a child's prescribed medicine to another child in their care, and 49.8% reported having leftover prescription medicines at home. Of those who borrowed medicines (n = 164), 56.1% received written medication instructions from the lender, and of the lenders (n = 155), 47.1% provided verbal instructions with the lent medicines. The sharing of prescription medicines in Auckland appears to be similar to that reported in other developed countries, and it is now clear that information provision while sharing does not always occur. Approaches to reduce harm resulting from sharing medicines should be explored.

  5. Geographies of inequality: child pedestrian injury and walking school buses in Auckland, New Zealand.

    PubMed

    Collins, Damian C A; Kearns, Robin A

    2005-01-01

    In the face of mounting concern at traffic congestion in the vicinity of schools and the associated risks of child pedestrian injury, the 'walking school bus' (WSB) idea has been rapidly adopted within metropolitan Auckland. WSBs involve volunteers guiding children to and from school in an orderly manner following established walking routes. This paper reports on a survey of the 34 Auckland primary schools which had adopted the scheme by November 2002. Despite rates of child pedestrian injury being highest in areas of socio-economic deprivation, our survey found WSB developments highly concentrated in low deprivation neighbourhoods. The inequitable socio-spatial distribution of WSBs in Auckland suggests that the ability to respond to road safety issues is closely correlated with socio-economic privilege. While our respondents identified a number of individual and community health benefits accruing from WSBs, we conclude that the initiative has a limited ability to address public health challenges originating within an inequitable and car-dominated urban political system.

  6. Temporal trends of acute nephrolithiasis in Auckland, New Zealand.

    PubMed

    Du, Jason; Johnston, Richard; Rice, Michael

    2009-07-24

    An increasing amount of evidence suggests that the occurrence of kidney stone disease has increased over the last 50 years. No data analysis on temporal trends in Auckland, New Zealand has ever been performed. The aim of this study was to investigate the changing pattern by age, ethnicity, and gender on stone incidence over a 10-year period. Demographic data was collected on all patients who presented with renal colic. Population numbers were provided by the New Zealand ministry of statistics using regular census data. The analysis was performed using Pearson's correlation coefficients and a Poisson regression model. From 1997 to 2007, 17,532 new stones were coded as nephrolithiasis with an age range of 1-97. Disease incidence amongst Auckland residents was greater in 2007 than 1997 (0.131% or 131 per 100,000 population vs 0.102% or 102 per 100,000 population. p=0.012). The male to female ratio changed over time with a greater proportion of females presenting in 2007 than 1997 (0.47 vs 0.41, p<0.05). Pacific, Asian, and Maori incidence increased faster compared to European whilst those from the Middle East were the only group to have a stable rate (0.26% or 260/100,000 per year) over the 10-year period. Incidence of kidney stone disease in the Auckland region has increased significantly from 1997 to 2007. Different ethnic groups had different rates of change, but all groups showed an increasing incidence over time, with the exception of those from the Middle East. A greater proportion of patients are female than 10 years ago.

  7. Decompression illness in divers treated in Auckland, New Zealand, 1996-2012.

    PubMed

    Haas, Rachel M; Hannam, Jacqueline A; Sames, Christopher; Schmidt, Robert; Tyson, Andrew; Francombe, Marion; Richardson, Drew; Mitchell, Simon J

    2014-03-01

    The treatment of divers for decompression illness (DCI) in Auckland, New Zealand, has not been described since 1996, and subsequent trends in patient numbers and demographics are unmeasured. This was a retrospective audit of DCI cases requiring recompression in Auckland between 01 January 1996 and 31 December 2012. Data describing patient demographics, dive characteristics, presentation of DCI and outcomes were extracted from case notes and facility databases. Trends in annual case numbers were evaluated using Spearman's correlation coefficients (ρ) and compared with trends in entry-level diver certifications. Trends in patient demographics and delay between diving and recompression were evaluated using regression analyses. There were 520 DCI cases. Annual caseload decreased over the study period (ρ = 0.813, P < 0.0001) as did entry level diving certifications in New Zealand (ρ = 0.962, P < 0.0001). Mean diver age was 33.6 (95% confidence limits (CI) 32.7 to 34.5) years and age increased (P < 0.0001) over the study period. Median (range) delay to recompression was 2.06 (95% CI 0.02 to 23.6) days, and delay declined over the study period (P = 0.005). Numbers of DCI cases recompressed in Auckland have declined significantly over the last 17 years. The most plausible explanation is declining diving activity but improvements in diving safety cannot be excluded. The delay between diving and recompression has reduced.

  8. An exploratory wastewater analysis study of drug use in Auckland, New Zealand.

    PubMed

    Lai, Foon Yin; Wilkins, Chris; Thai, Phong; Mueller, Jochen F

    2017-09-01

    New Zealand is considered to have unusual drug use patterns by international standards. However, this understanding has largely been obtained from social surveys where respondents self-report use. The aim of this paper is to conduct the first wastewater study of drug use in Auckland. Wastewater sampling was completed from 2 May to 18 July 2014 at 2 Auckland wastewater treatment plants which service 1.3 million people. Samples were analysed for 17 drug residues by using liquid chromatography-tandem mass spectrometry. Consumption of methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), cocaine, codeine and methadone (mg/day/1000 people) was estimated by using a back-calculation formula. Methamphetamine, codeine, morphine and methadone were detected with high frequency (80-100%), followed by amphetamine (~60%), MDMA (~7%, i.e. 8 occasions) and methylone (3 occasions). An overall mean of 360 mg of methamphetamine and 60 mg of MDMA was estimated to have been consumed per day per 1000 people. Methamphetamine consumption was found at similar levels in both catchments (377 and 351 mg/day/1000 people). Cocaine was only detected in 1 catchment and on only 8 occasions. JWH-018 was detected in 1 catchment and only on 1 occasion. Methamphetamine, codeine and other opioids were detected at a consistent level throughout the week. 3,4-Methylenedioxymethamphetamine and methylone were detected only during the weekends. Wastewater analysis confirms that methamphetamine was one of the most commonly detected illegal drugs in Auckland and was detected consistently throughout the week. In contrast, cocaine and MDMA were rarely detected, with detection limited to weekends. [Lai FY, Wilkins C, Thai P, Mueller JF. An exploratory wastewater analysis study of drug use in Auckland, New Zealand. Drug Alcohol Rev 2017;00:000-000]. © 2017 Australasian Professional Society on Alcohol and other Drugs.

  9. Ethnicity of severe trauma patients: results of a population-based study, Auckland, New Zealand 2004.

    PubMed

    Creamer, Gowan; Civil, Ian; Ng, Alex; Adams, David; Cacala, Shas; Koelmeyer, Timothy; Thompson, John

    2010-06-11

    To investigate the role of Māori and Pacific ethnicity within the severe trauma and population demographics of Auckland, New Zealand. A population-based study utilising prospectively gathered trauma databases and coronial autopsy information. Population data was derived from Statistics New Zealand resident population projections for the year 2004. The geographic boundaries of the Auckland district health boards (Waitemata DHB, Auckland DHB and Counties-Manukau DHB). Severe injury was defined as death or injury severity score more than 15. Combining data from coronial autopsy and four hospital trauma databases provided age, gender, ethnicity, mechanism, mortality and hospitalisation information for severely injured Aucklanders. Māori and Pacific had increased risk of severe injury and injury-related mortality. A major gender difference is apparent: Māori female at increased risk and Pacific female at decreased risk compared to the remaining female population; both Māori and Pacific male have high severe injury rate than the remaining population. The relative risk for severe injury (and mortality) for Māori RR=2.38 (RR=2.80) and Pacific RR=1.49 (RR=1.59) is higher than the remaining population, the highest risk (and more statistically significant) is seen in the 15-29 age group (Māori RR=2.87, Pacific RR=2.57). Road traffic crashes account for the greatest proportion of injuries in all groups. Māori have relatively higher rates of hanging and assault-related injury and death; Pacific have relatively higher rates of falls and assault. Ethnicity is a factor in severe injury and mortality rates in Auckland. Age is an important influence on these rates. Although mechanism of injury varies between ethnic groups, no particular mechanism of injury accounts for the overall differences between groups.

  10. Suicide trends in an expanding mental health service in Auckland.

    PubMed

    Argyle, Nick

    2010-10-01

    Suicide is a global health priority. It is important to analyse the effects of investment in mental health services on suicide rates. This paper presents and discusses recent changes in suicide rates and diagnostic mix among clients of the mental health service in Auckland during a time of service growth. Details of suicides among current clients were analysed for the years 1993 to 2006, comparing the periods 1993-1999 and 2000-2006. These periods were compared with the local population and national figures. The local population suicide rate decreased significantly with the rate among clients increasing slightly so the proportion occurring among clients increased (up to 31%). There was an increase in non-psychotic diagnoses. As access to services expands the proportion of suicides that occur in known clients will paradoxically increase. Service expansion may have contributed to the falling population suicide rate in Auckland.

  11. A Tale of Two Olivines: Magma Ascent in the Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Smid, E. R.; McGee, L. E.; Smith, I. E.; Lindsay, J. M.

    2013-12-01

    The Auckland Volcanic Field (AVF) is a nephelinitic to subalkali basaltic monogenetic field centered on the city of Auckland, New Zealand. Lavas are olivine-phyric, and the deposits of several volcanoes in the field contain olivine crystals with chrome spinel (Cr-spinel) inclusions. Microprobe analyses show at least two populations of olivine, categorised by their Mg# and their spinel inclusion compositions: the first has olivines that are euhedral, have compositions slightly less forsteritic than expected for whole rock Mg#, and have Cr-spinel inclusions with relatively low Cr2O3 contents of ~20%. These are interpreted as antecrysts inherited from the mantle source that yielded their host magma. The second population is characterised by olivines that are sub- to euhedral, are significantly more forsteritic than expected from their host whole rock Mg#, and have Cr-spinel inclusons with relatively high Cr2O3 contents of ~50%. These are interpreted as xenocrysts. The composition of these high Cr2O3 spinels very closely resembles the composition of spinels within olivines in dunite sampled from the Dun Mountain Ophiolite on the South Island of New Zealand. The northward extension of the Dun Mountain complex beneath the North Island is defined by the Junction Magnetic Anomaly, marking a crustal terrane boundary that underlies the Auckland Volcanic Field. These data indicate that the magmas that have risen to produce the volcanoes of the Auckland Volcanic Field have carried crystals from an underlying ultramafic crust as well as from their asthenospheric source. Euhedral olivine crystals which do not contain Cr-spinel are also present in AVF lavas and these are interpreted as true phenocrysts that crystallised directly from their host magmas. The lack of reaction textures at crystal margins suggests rapid ascent rates. A crustal origin for the xenocrysts not only has large implications for ascent rate modelling of olivines, but also for the crustal structure of the

  12. An evaluation of consumers' knowledge, perceptions and attitudes regarding generic medicines in Auckland.

    PubMed

    Babar, Zaheer-Ud-Din; Stewart, Joanna; Reddy, Shiwangni; Alzaher, Woroud; Vareed, Prateeka; Yacoub, Nineweh; Dhroptee, Bandhana; Rew, Anne

    2010-08-01

    The aim of this project was to evaluate the perceptions, knowledge and attitudes regarding generic medicines. A cross-sectional study, with self administered questionnaires, was conducted to survey consumers visiting pharmacies in four regions of Auckland (North Shore, Waitakere, Central Auckland and South Auckland). Through stratified random sampling, approximately 10% of pharmacies from each region were selected, which turn out to be 30 pharmacies. Every alternate customer coming to the pharmacy, who was eligible to participate in the study, was asked by the researchers to complete the questionnaire. A total of 441 questionnaires were included in the analysis. Different response rates were obtained in different regions of Auckland. Of all respondents, 51.6% had previous knowledge of generic medicines. Pharmacists were the main source of information regarding generic medicines followed by doctors and media. A higher level of education had a direct relationship with having correct knowledge of generics (P = .002). Attitude of participants toward the use of generic medicines was determined by their knowledge of generics, whether it was recommended by a pharmacist and their type of illness. Participants were more prepared to change to a generic for a minor illness (79%) than for a major illness (58.7%). Those who had better knowledge were more likely than those with poor knowledge to say they would to use a generic in major illness (P = .001) as well as minor illness (P < .0001). Previous positive experiences with generics also determined consumers' willingness to use generics. Many consumers have misconceptions regarding generic medicines. Having knowledge about generics and the advice by doctors and pharmacists are key indicators to improve the quality use of generic medicines.

  13. Enteric fever in the Pacific: a regional retrospective study from Auckland, New Zealand.

    PubMed

    Lane, R J; Holland, D; McBride, S; Perera, S; Zeng, I; Wilson, M; Read, K; Jelleyman, T; Ingram, R J H

    2015-02-01

    There are limited clinical data on enteric fever in the Pacific and New Zealand (NZ) compared with the Indian subcontinent (ISC) and South-East Asia (SEA). Our objective was to describe enteric fever in Auckland - a large Pacific city, focusing on disease acquired in these regions. We reviewed enteric fever cases hospitalised in Auckland from January 2005 to December 2010. Microbiologically confirmed EF was identified in 162 patients. Travel regions: Pacific, 40 cases (25%) (Samoa, 38; Fiji, two), ISC, 72 (44%), SEA, seven (4%), other, three (2%), no travel, 40 (25%). Enteric fever rates for Auckland resident travellers were: India 50.3/100 000; Samoa 19.7/100 000.All Pacific cases were Salmonella Typhi. Of local isolates (without travel history), 38 were S. Typhi (36 fully susceptible, one multi-drug resistant (MDR) + nalidixic acid resistant (NAR), one unknown) and two S. Paratyphi (both NAR). Of non-Pacific travel, 56/82 (69%) isolates were S. Typhi, the remainder S. Paratyphi (15 isolates were fully susceptible, only 1% were MDR). Significant associations of serotype and antibiotic resistance with different travel regions and similarity of phage types (local and Pacific) were observed. Headache, vomiting and acute kidney injuries were more frequent with Pacific travel, while abdominal distension and cholecystitis with local disease. Shorter duration of treatment in the Pacific group was seen despite length of stay in hospital not being reduced. Local cases were associated with longer hospital admissions. One half of cases in Auckland are acquired either from Pacific or locally. Similarities mean that disease acquired locally is likely of Pacific origin. © 2014 Royal Australasian College of Physicians.

  14. Postgraduation retention of medical students from Otago and Auckland medical programmes.

    PubMed

    Shelker, William; Poole, Phillippa; Bagg, Warwick; Wood, Ian; Glue, Paul

    2014-01-24

    Auckland and Otago medical programmes have different methods for selecting students. This study compared postgraduate retention in New Zealand (NZ) of medical graduates from the two medical programmes, to assess whether different selection methods influenced retention. Other variables assessed included entrance category and age at graduation. Anonymised databases were created of all graduates from the Otago Faculty of Medicine (1999-2011) and the Auckland medical programme (2000-2012). Demographic and entry category data were recorded. Retention was defined as presence on the NZ Medical Register in December 2012. Risk differences (RD) were calculated to compare retention between the two medical programmes using the Mantel-Haenszel method. The influence of medical programme entrance category on retention was also tested. The influence of covariates on retaining graduates on the register was evaluated using a multiple logistic regression model. The postgraduate retention of graduates of the two medical programmes over 13 years was identical (Auckland 74.9%, Otago 73.6%, P=0.48). Retention of graduate and non-graduate entry students from both medical programmes was similar by 6 years after graduation. Age during medical school did not affect retention. University of attendance had no effect on postgraduation retention of students on the NZ Medical Register, suggesting that retention is not influenced by the different student selection methods at each programme. The data presented shows that New Zealand graduates regardless of programme completed show a similar profile in terms of retention.

  15. Haemophilus influenzae type b disease in Auckland children during the Hib vaccination era: 1995-2009.

    PubMed

    Leung, Bonnie; Taylor, Susan; Drinkovic, Dragana; Roberts, Sally; Carter, Phil; Best, Emma

    2012-11-09

    To characterise Haemophilus influenzae type b (Hib) invasive disease in the era of Hib vaccination, in children of the greater Auckland region of New Zealand. Identification of sterile site culture positive Hib via the Auckland hospital laboratories databases and national laboratory surveillance database in the time period; 1995 to 2009. There were a total of 26 cases in the Auckland Region. Over the 15-year period, the annual incidence of invasive Hib disease was 0.61 per 100,000 (95% CI: 0.4-0.9) for children aged under 15 years and 1.65 per 100,000 (95% CI: 1.1-2.5) for children aged under 5 years. Ninety-two percent were under 5 years and 54% were under 1 year. Sixty percent of the children were of Maori and Pacific ethnicity. The predominant diagnosis was meningitis, accounting for 15 cases (60%). There were no fatalities. Forty-eight percent of affected children were completely unimmunised with the Hib vaccine which has been fully funded on the National Immunisation Schedule since 1994. Since the introduction of the Hib vaccine, the disease rates have greatly reduced in the Auckland region. Although ethnic disparities have improved amongst the cases that occur, immunisation rates in cases are low and infants remain most at risk. Current emphasis on intensifying immunisation programmes to achieve higher vaccination rates and timeliness of delivery will help in efforts to achieve elimination of the disease in New Zealand.

  16. Is a rheumatic fever register the best surveillance tool to evaluate rheumatic fever control in the Auckland region?

    PubMed

    Moxon, Te Aro; Reed, Peter; Jelleyman, Timothy; Anderson, Philippa; Leversha, Alison; Jackson, Catherine; Lennon, Diana

    2017-08-11

    To determine the most accurate data source for acute rheumatic fever (ARF) epidemiology in the Auckland region. To assess coverage of the Auckland Regional Rheumatic Fever Register (ARRFR), (1998-2010) for children <15 years and resident in Auckland at the time of illness, register, hospitalisation and notification data were compared. A consistent definition was applied to determine definite and probable cases of ARF using clinical records. (www.heartfoundation.org.nz) RESULTS: Of 559 confirmed (definite and probable) RF cases <15 years (median age 10 years), seven were recurrences. Of 552 first episodes, the ARRFR identified 548 (99%), hospitalisations identified 501 (91%) including four not on the register, and public health notifications identified 384 (70%). Of hospitalisation cases, 33% (245/746), and of notifications 20% (94/478) did not meet the case definition and were therefore excluded. Between 1998-2010, eight cases, initially entered as ARF on the ARRFR, were later removed once further clinical detail was available. The ARRFR produced the most accurate information surrounding new cases of ARF (for children <15 years) for the years 1998-2010 in Auckland. This was significantly more accurate than medical officer of health notification and hospitalisation data.

  17. A tale of two cities: paradoxical intensity of traffic calming around Auckland schools.

    PubMed

    Hopgood, Timothy; Percival, Teuila; Stewart, Joanna; Ameratunga, Shanthi

    2013-05-10

    The school journey is a common context for child pedestrian injuries in New Zealand, with children from low socioeconomic, Maori or Pacific families being at increased risk. The extent to which evidence-based environmental strategies that can address this problem are equitably implemented is unclear. To determine if there is a difference in the distribution of traffic-calming modifications around schools in areas of high and low socioeconomic deprivation in Auckland and Manukau Cities, New Zealand. From a list of the most and least socioeconomically deprived schools in Auckland and Manukau Cities, 40 of each were randomly selected. The number of modifications within a 1 km radius of these schools was recorded in December 2009 or January 2010. The association of deprivation and region with the numbers of traffic-calming modifications was examined using a general linear model. Socioeconomically least deprived schools had more traffic-calming interventions than the most deprived schools (least square mean (LSM): 25 versus 18; p=0.05), and Auckland schools had more interventions than Manukau schools (LSM: 27 versus 16; p=0.001). Traffic-calming measures were observed more commonly in less deprived areas where the risks of child pedestrian injuries are generally lower. This apparent paradox could result in increasing socioeconomic inequities in the distribution of child pedestrian injuries.

  18. Ethnic, socioeconomic and geographical inequalities in road traffic injury rates in the Auckland region.

    PubMed

    Hosking, Jamie; Ameratunga, Shanthi; Exeter, Daniel; Stewart, Joanna; Bell, Andrew

    2013-04-01

    To describe ethnic, socioeconomic and geographical differences in road traffic injury (RTI) within Auckland, New Zealand's largest city. We analysed rates of RTI deaths and non-fatal hospital admissions using the New Zealand Mortality Collection and the National Minimum Data Set 2000-08. Poisson regression examined the association of age, gender, prioritised ethnicity and small area deprivation (New Zealand Index of Deprivation) with RTI rates, and RTI rates were mapped for 21 local board areas within the Auckland region. While RTI rates increased with levels of deprivation in all age groups, the gradient was steepest among children (9% increase/decile) and adults aged 25-64 years (11% increase/decile). In all age groups, RTI risk was highest among Māori. Pacific children had an elevated risk of RTI compared with the NZ European/Other group, but Pacific youth (15-24 years) and adults (25-64 years) had a lower risk. While RTI rates were generally higher for those living in rural local board areas, all but one local board in the southern Auckland urban area had among the highest rates. There are substantial ethnic, socioeconomic and geographic inequalities in RTI risk in the Auckland region, with high rates among Māori (all ages), Pacific children, people living in socioeconomically deprived neighbourhoods, the urban south and rural regions. To meet the vision of regional plans, road safety efforts must prioritise vulnerable communities at greatest risk of RTI, and implement and monitor the effectiveness of strategies that specifically include a focus on reducing inequalities in RTI rates. © 2013 The Authors. ANZJPH © 2013 Public Health Association of Australia.

  19. Development of a risk assessment tool for volcanic urban environments: RiskScape and the Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Deligne, N. I.; Leonard, G.; King, A.; Wilson, G.; Wilson, T.; Lindsay, J. M.

    2013-12-01

    Auckland city, home to a third of New Zealand's population, is situated on top of the Auckland Volcanic Field (AVF), which last erupted roughly 500 years ago. Since 2008, the Determining Volcanic Risk in Auckland (DEVORA) program has investigated the geologic context of the AVF, improved timing constraints of past eruptions, explored possible tempo-spatial-volume eruption trends, and identified likely styles and hazards of future eruptions. DEVORA is now moving into development of risk and societal models for Auckland. The volcanic module of RiskScape, a multi-hazard risk assessment tool developed by Crown Research Institutes GNS Science and NIWA, will be expanded and used to model risk and impact to the built environment and population caused by a future AVF eruption. RiskScape models casualties, damage and disruption caused by various hazards, the resulting reduced functionality of assets, and associated clean up costs. A strength of RiskScape is that the effect of various mitigation strategies can be explored by strengthening asset attributes and examining resulting changes in the output risk evaluation. We present our framework for building a volcano hazard exposure module for RiskScape along with our approach for assessing asset vulnerability through the development of fragility functions. We also present the framework for engagement with regional Auckland stakeholders, including representatives of local and regional governments and utility companies, to identify complementary needs to ensure that final risk products are relevant and useable by end users.

  20. A Probabilistic Tsunami Hazard Study of the Auckland Region, Part II: Inundation Modelling and Hazard Assessment

    NASA Astrophysics Data System (ADS)

    Lane, E. M.; Gillibrand, P. A.; Wang, X.; Power, W.

    2013-09-01

    Regional source tsunamis pose a potentially devastating hazard to communities and infrastructure on the New Zealand coast. But major events are very uncommon. This dichotomy of infrequent but potentially devastating hazards makes realistic assessment of the risk challenging. Here, we describe a method to determine a probabilistic assessment of the tsunami hazard by regional source tsunamis with an "Average Recurrence Interval" of 2,500-years. The method is applied to the east Auckland region of New Zealand. From an assessment of potential regional tsunamigenic events over 100,000 years, the inundation of the Auckland region from the worst 100 events is modelled using a hydrodynamic model and probabilistic inundation depths on a 2,500-year time scale were determined. Tidal effects on the potential inundation were included by coupling the predicted wave heights with the probability density function of tidal heights at the inundation site. Results show that the more exposed northern section of the east coast and outer islands in the Hauraki Gulf face the greatest hazard from regional tsunamis in the Auckland region. Incorporating tidal effects into predictions of inundation reduced the predicted hazard compared to modelling all the tsunamis arriving at high tide giving a more accurate hazard assessment on the specified time scale. This study presents the first probabilistic analysis of dynamic modelling of tsunami inundation for the New Zealand coast and as such provides the most comprehensive assessment of tsunami inundation of the Auckland region from regional source tsunamis available to date.

  1. Predicting geographically distributed adult dental decay in the greater Auckland region of New Zealand.

    PubMed

    Rocha, C M; Kruger, E; Whyman, R; Tennant, M

    2014-06-01

    To model the geographic distribution of current (and treated) dental decay on a high-resolution geographic basis for the Auckland region of New Zealand. The application of matrix-based mathematics to modelling adult dental disease-based on known population risk profiles to provide a detailed map of the dental caries distribution for the greater Auckland region. Of the 29 million teeth in adults in the region some 1.2 million (4%) are suffering decay whilst 7.2 million (25%) have previously suffered decay and are now restored. The model provides a high-resolution picture of where the disease burden lies geographically and presents to health planners a method for developing future service plans.

  2. Natural Hazard Preparedness in an Auckland Community: Child and Community Perceptions

    ERIC Educational Resources Information Center

    Bolton, Patricia; Dirks, Kim; Neuwelt, Pat

    2014-01-01

    Community engagement in natural hazard preparedness is crucial to ensure sustainable initiatives. Children are important members of communities, and can actively contribute to community preparedness. This article presents research undertaken with 11- to 12-year-old students from a school in Auckland, New Zealand, and leaders associated with the…

  3. Debt on graduation, expected place of practice, and career aspirations of Auckland Medical School students.

    PubMed

    O'Grady, G; Fitzjohn, J

    2001-10-26

    To determine the debt level that current Auckland medical students expect to graduate with, and evaluate this debt in the context of their career aspirations and intended place of practice. Simple check-box and fill-in-the-blank surveys were distributed to Auckland University medical students in Years 1 through to 5 during their second week of scheduled lectures in March 2000. Students were asked to provide demographic details, then complete sections on debt and career aspirations. 70% of Auckland medical students participated. Average expected debt was between $60000 to $70000. Predicted size of graduation debt was significantly related with plans to practice medicine overseas, and this trend was especially strong among females. In addition, Maori and Polynesian students bear a disproportionate level of the student debt burden compared to Pakeha and Asian groups. 77% of students indicated a preference for working in private or hospital specialty work. Student debt will have major effects on the composition of the New Zealand medical workforce over coming years. More attention must be paid to the national picture of medical student indebtedness if adequate workforce planning is to be possible.

  4. Adoption of endovenous laser treatment as the primary treatment modality for varicose veins: the Auckland City Hospital experience.

    PubMed

    Fernando, Ruchira S W; Muthu, Carl

    2014-08-01

    To assess the effectiveness of adopting endovenous laser treatment (EVLT) as the primary treatment modality for varicose veins at Auckland City Hospital (Auckland, New Zealand). The outcomes of 354 consecutive EVLT procedures performed between 2007 and 2013 were reviewed. Data was collected from a prospectively maintained procedural database and by retrospective chart review. Of the 319 patients who had an ultrasound, at 1 month post-procedure there was a saphenous vein occlusion rate of 96%. Side effects were minimal with no cases of DVT or skin burns and one case of self-limiting neuralgia. The procedure was well tolerated with a median pain score of 3. Since the adoption of EVLT there has been a large increase in the number of patients treated for varicose veins (28 in 2007 compared to 176 in 2013). EVLT is a safe and effective treatment for varicose veins and its adoption has allowed a large increase in the number of varicose vein patients treated at Auckland City Hospital.

  5. Investigation of zoonotic infections among Auckland Zoo staff: 1991-2010.

    PubMed

    Forsyth, M B; Morris, A J; Sinclair, D A; Pritchard, C P

    2012-12-01

    Investigation was undertaken to assess the occurrence of zoonotic infection among staff at Auckland Zoological Park, New Zealand, in 1991, 2002 and 2010. Serial cross-sectional health surveys in 1991, 2002 and 2010 comprising a health questionnaire, and serological, immunological and microbiological analysis for a range of potential zoonotic infections were performed. Laboratory results for zoo animals were also reviewed for 2004-2010 to assess the occurrence of potential zoonotic infections. Veterinary clinic, animal handler, grounds, maintenance and administrative staff participated in the surveys, with 49, 42 and 46 participants in the 1991, 2002 and 2010 surveys, respectively (29% of total zoo staff in 2010). A small number of staff reported work-related infections, including erysipelas (1), giardiasis (1) and campylobacteriosis (1). The seroprevalence of antibodies to hepatitis A virus and Toxoplasma gondii closely reflected those in the Auckland community. No carriage of hepatitis B virus (HBV) was detected, and most of those with anti-HBV antibodies had been vaccinated. Few staff had serological evidence of past leptospiral infection. Three veterinary clinic staff had raised Chlamydophila psittaci antibodies, all < 1 : 160 indicating past exposure. Two staff (in 1991) had asymptomatic carriage of Giardia lamblia and one person (in 2010) had a dermatophyte infection. After 1991, positive tests indicating exposure to Mycobacterium tuberculosis were < 10%, comparable to the general New Zealand population. Zoo animals had infections with potential zoonotic agents, including G. lamblia, Salmonella spp., Campylobacter spp. and T. gondii, although the occurrence was low. Zoonotic agents pose an occupational risk to zoo workers. While there was evidence of some zoonotic transmission at Auckland Zoo, this was uncommon and risks appear to be adequately managed under current policies and procedures. Nevertheless, ongoing assessment of risk factors is needed as

  6. Demographic variation in community-based MRSA skin and soft tissue infection in Auckland, New Zealand.

    PubMed

    Ritchie, Stephen R; Fraser, John D; Libby, Eric; Morris, Arthur J; Rainey, Paul B; Thomas, Mark G

    2011-04-15

    To estimate the burden of skin and soft tissue infection caused by Staphylococcus aureus (S. aureus), and to determine the effects of ethnicity and age on the rate of skin and soft tissue due to MRSA in the Auckland community. We reviewed the culture and susceptibility results of all wound swabs processed by Auckland's only community microbiology laboratory in 2007. Demographic data for a random sample of 1000 people who had a wound swab collected and for all people from whom a methicillin-resistant S. aureus (MRSA) strain was isolated were obtained and compared to demographic data for the total population of Auckland. S. aureus was isolated from 23853/47047 (51%) wound swab cultures performed in 2007; the estimated annual incidence of S. aureus isolation from a wound swab was 1847/100,000 people; and the estimated annual incidence of MRSA isolation from a wound swab was 145/100,000 people. Maori and Pacific people had higher rates of non-multiresistant MRSA infection compared with New Zealand European and Asian people; elderly New Zealand European people had much higher rates of multiresistant MRSA infections compared with people from other ethnic groups. S. aureus is a very common cause of disease in the community and the incidence of infection with MRSA subtypes varies with ethnicity.

  7. Sudden unexpected infant death in Auckland: a retrospective case review.

    PubMed

    Hutchison, B Lynne; Rea, Charlotte; Stewart, Alistair W; Koelmeyer, Timothy D; Tipene-Leach, David C; Mitchell, Edwin A

    2011-08-01

    To review autopsy reports of all SUDI deaths in the Auckland region, New Zealand, from October 2000 to December 2009. Information on all SUDI cases from 2000 to 2009 was extracted from autopsy and police reports from the National Forensic Pathology Service at Auckland Hospital. Of the 332 post-mortems in this period, 221 were classified as SUDI. Of these, 83% were Māori or Pacific infants. The median age at death was 11 weeks and 11% occurred in 7- to 28-day-olds. At the time of death, 64% overall were bedsharing; this was more common in 7-28 day olds (92%). Bedsharing infants were significantly younger at death than non-bedsharing infants (p=0.008). Where sleep position was known, 57% were placed in non-supine at the last sleep. There was no evidence of diagnostic shift and the prevalence of bedsharing did not change over the decade. Bedsharing was associated with a high proportion of SUDI cases, especially in the youngest infants, and non-supine sleep positions were common. There is a need to enhance SUDI prevention messages and consider innovative ways of promoting safe sleeping environment and supine sleep position in Māori and Pacific communities. © 2011 The Author(s)/Acta Paediatrica © 2011 Foundation Acta Paediatrica.

  8. Characteristics of University of Auckland medical students intending to work in the regional/rural setting.

    PubMed

    Pasley, Thomas; Poole, Phillippa

    2009-04-03

    To assess the level of interest in regional/rural (RR) practice in final year Auckland medical students and to investigate the demographic characteristics and speciality intentions of these students. A questionnaire was distributed to all graduating students from The University of Auckland's School of Medicine (SOM) in 2006 and 2007. Students intending to work in a RR setting had their demographic data and intended specialty compared with students intending to work in the city. There were 186 respondents, with a response rate of 71%. Of this cohort, 58% stated an intention to work in a city, 15% in an RR setting, and 27% were undecided. RR-destined students were more likely to be Maori and less likely to be Asian then their city-destined counterparts. RR students were more likely to have strong interests in general practice than students intending to work in the city. Prior to the introduction of a specific rural selection pathway, Auckland medical students have shown a similar level of interest in RR medicine when compared to previous studies. However the proportion of students interested in RR health is significantly below the current proportion of people living in RR areas. The large proportion of students undecided on career setting at graduation suggests there may be room to increase the proportion further through formative early postgraduate experiences, or other incentives.

  9. Keeping track of antimicrobial resistance for Neisseria gonorrhoeae in Auckland, New Zealand: past, present and future considerations.

    PubMed

    McAuliffe, Gary; Smith, Marian; Brokenshire, Mike; Forster, Rose; Reid, Murray; Roberts, Sally

    2018-06-22

    Neisseria gonorrhoeae (NG) has developed resistance to a wide range of antimicrobials. Population level data is essential to determine empiric treatment regimes. We sought to identify antimicrobial resistance patterns for NG in the Auckland region from 2008-2016, and review the utility of current methods of antimicrobial resistance testing. Antimicrobial susceptibilities and demographic data from NG isolates derived from patients attending the Auckland Regional Sexual Health Service and Auckland City Hospital were analysed to determine resistance rates and trends over time. Antimicrobial susceptibility testing was performed by agar dilution using Clinical and Laboratory Standards Institute (CLSI) interpretation criteria. Results for 2,302 isolates from 1,941 patients were analysed. While ciprofloxacin resistance increased between 2008 and 2011, resistance rates for all antibiotics declined from 2013-2016. In 2016, 22% (53) of isolates were resistant to ciprofloxacin, 7% (17) to penicillin, 31% (76) to tetracycline and 0.8% (2) exhibited decreased susceptibility to ceftriaxone. Ceftriaxone is still suitable as a component of gonorrhoea treatment in our region but resistance to other agents prohibits their use for empiric treatment regimens. Current methods of detecting antimicrobial resistance for NG needed to be updated so that they are fit for purpose.

  10. The New Zealand-Born Chinese Community of Auckland: Aspects of Language Maintenance and Shift.

    ERIC Educational Resources Information Center

    Sun, Susan

    1999-01-01

    Examines the Chinese immigrant community in Auckland, New Zealand and how they address the question of first language maintenance in their largely new English-speaking environment. Shows that language maintenance, especially the written language is going to be an uphill struggle. (Author/VWL)

  11. Use of the EpiNet database for observational study of status epilepticus in Auckland, New Zealand.

    PubMed

    Bergin, Peter; Jayabal, Jayaganth; Walker, Elizabeth; Davis, Suzanne; Jones, Peter; Dalziel, Stuart; Yates, Kim; Thornton, Vanessa; Bennett, Patricia; Wilson, Kaisa; Roberts, Lynair; Litchfield, Rhonda; Te Ao, Braden; Parmer, Priya; Feigin, Valery; Jost, Jeremy; Beghi, Ettore; Rossetti, Andrea O

    2015-08-01

    The EpiNet project has been established to facilitate investigator-initiated clinical research in epilepsy, to undertake epidemiological studies, and to simultaneously improve the care of patients who have records created within the EpiNet database. The EpiNet database has recently been adapted to collect detailed information regarding status epilepticus. An incidence study is now underway in Auckland, New Zealand in which the incidence of status epilepticus in the greater Auckland area (population: 1.5 million) will be calculated. The form that has been developed for this study can be used in the future to collect information for randomized controlled trials in status epilepticus. This article is part of a Special Issue entitled "Status Epilepticus". Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Constructing the Community: Secondary Schools and Their Neighborhoods in 20th Century Auckland.

    ERIC Educational Resources Information Center

    McCulloch, Gary

    1992-01-01

    Discussion of the relationship between the character of the community and secondary schools in developing urban and suburban neighborhoods of Auckland (New Zealand) looks at such factors as location, transportation, and social/ethnic geography. Focus is on the political nature of school construction and recent evolution of national public policy…

  13. Differences in health-related socioeconomic characteristics among Pacific populations living in Auckland, New Zealand.

    PubMed

    Sundborn, Gerhard; Metcalf, Patricia; Schaaf, David; Dyall, Lorna; Gentles, Dudley; Jackson, Rodney

    2006-01-27

    To describe, compare and contrast the health-related socioeconomic characteristics of the different Pacific ethnic groups surveyed in the Auckland Diabetes, Heart and Health Survey (DHHS). The DHHS was carried out in Auckland in 2002-2003. Electoral roll based sampling and cluster sampling strategies were used to recruit a representative sample of Auckland Pacific populations. Participants answered a self-administered questionnaire about their demographic and socioeconomic position. The study surveyed 1011 Pacific people aged between 35-74 years of age. Of the 1011 Pacific participants, 484 were of Samoan, 255 Tongan, 116 Cook Island, 109 Niuean, 26 Fijian, and 21 were of 'Other Pacific' ethnic groups. Samoans were least likely to have no children, and most likely to hold a certificate qualification. Tongans were least likely to be born in New Zealand (NZ) and had the shortest residence time in NZ. Tongans were most likely to be married and had the largest families. Cook Islanders were most likely to be NZ-born and had the highest household income. Niueans were most likely to be in paid employment, to hold a diploma qualification, to own their own homes, and have the smallest families. In conclusion, a distinct pattern (continuum) emerged from the results. The Cook Island and Niuean ethnic groups generally had a similar and more favourable socioeconomic profile compared to the Samoan and Tongan ethnic groups. These differences are most likely to be related to the length of residence in NZ. As differences existed, each Pacific ethnic group should be investigated separately when there are sufficient numbers.

  14. A review of a regional primary percutaneous coronary intervention service, with a focus on door to reperfusion times: the 2012 Auckland/Northland experience.

    PubMed

    Lin, Aaron; Oh, Timothy; Alawami, Mohammed; Webster, Mark; El-Jack, Seif; Scott, Douglas; Stewart, James; Ormiston, John; Armstrong, Guy; Khan, Ali; Kay, Patrick; Harrison, Wil; Kerr, Andrew; McGeorge, Alastair; Gamble, Greg; Ruygrok, Peter; Ellis, Chris J

    2015-01-01

    Primary percutaneous coronary intervention (PCI) is the optimal management for ST segment elevation myocardial infarction (STEMI) patients. We reviewed the largest primary PCI regional service in New Zealand: the Auckland/Northland service based at Auckland City Hospital, to assess patient management, in particular the door to reperfusion times (DTRTs), and predictors of death in hospital. We obtained patient details from a comprehensive prospective database of all primary PCI patients admitted with STEMI from 1/1/12 to 31/12/12 to the Auckland City Hospital cardiac catheterisation laboratory. Of four District Health Boards (DHBs) within the region, two accessed this regional service at all times, and two accessed the Auckland City Hospital cardiac catheterisation laboratory 'after hours': all times except for 08:00 to 16:00 hours on Monday to Friday. A total of 401 adult patients underwent a primary PCI at the Auckland City Hospital Regional centre for a STEMI presentation, over the 12 months period. The median patient age was 61 years, 77% were male. Overall 183 (46%) (95% CI 41, 51) patients achieved a DTRT of < 90 mins, and 266 (66%) (95% CI 61, 71) a DTRT of < 120 mins, with a clear geographical influence to these times. Of 27 patients with direct transfer to the catheter laboratory from the community, the DTRT was < 120 mins in 24 (92%) (95% CI 72, 96) patients. In-hospital mortality was 24 (6%) patients (95% CI 4, 9). The 2012 Auckland/Northland primary PCI service delivers good outcomes consistent with current Australasian standards. Although geographical isolation complicates door to reperfusion times, these may potentially be improved by more focus on direct transfer to the cardiac catheterisation laboratory, especially directly from the community. Copyright © 2014 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  15. Geography matters: the prevalence of diabetes in the Auckland Region by age, gender and ethnicity.

    PubMed

    Warin, Briar; Exeter, Daniel J; Zhao, Jinfeng; Kenealy, Timothy; Wells, Susan

    2016-06-10

    To determine whether the prevalence of diagnosed diabetes in the greater Auckland Region varies by General Electoral District (GED). Using encrypted National Health Identifiers and record linkage of routine health datasets, we identified a regional cohort of people with diagnosed diabetes in 2011 from inpatient records and medication dispensing. The geographical unit of a person's residence (meshblock) was used to determine the GED of residence. We calculated prevalence estimates and 95% confidence intervals and used binary logistic regression to map geographical variations in diabetes. An estimated 63,014 people had diagnosed diabetes in Auckland in 2011, a prevalence of 8.5% of the adult population ≥30 years of age. We found significant variation in diabetes prevalence by age, gender, ethnicity and GED. There was a more than five-fold difference in the unadjusted prevalence of diabetes by GED, ranging from 3.2% (3.1 to 3.4%) in the North Shore to 17.3% (16.8 to 17.7%) in Mangere. Such variations remained after binary logistic regression adjusting for socio-demographic variables. Compared to New Zealand Europeans, Indian people had the highest odds of having diabetes at 3.85 (3.73 to 3.97), while the odds of people living in the most deprived areas having diabetes was nearly twice that of those living in least deprived areas (OR 1.93, [1.87 to 1.99]). Geographic variations in diabetes remained after adjusting for socio-demographic circumstances: people living in GEDs in south-west Auckland were at least 60% more likely than people living in the North Shore GED to have diabetes. There is significant variation in the prevalence of diabetes by GED in Auckland that persists across strata of age group, gender and ethnicity, and persists after controlling for these same variables. These inequities should prompt action by politicians, policymakers, funders, health providers and communities for interventions aimed at reducing such inequities. Geography and its

  16. The epidemiology of plunging ranula in South Auckland.

    PubMed

    Chin, Seung Joon; Zeng, Irene S L; Morton, Randall P

    2016-12-01

    Estimate the incidence rate and provide basic descriptive epidemiologic characteristics of plunging ranulas in a multi-ethnic population. Case series with chart review. The study group comprised all Counties Manukau Health (CMH, Manukau City, Auckland, New Zealand) patients presenting to the CMH Department of Otolaryngology with a diagnosis of plunging ranula from January 2001 to December 2013, as recorded in the departmental case register. Non-CMH domicile patients were excluded. South Auckland comprised the base population, as serviced by CMH. The 2006 New Zealand census data was used for population demographics. A total of 134 cases of plunging ranula were identified. The overall annual crude incidence rate was 2.4 per 100,000 person-years. The gender specific incidence rate for males was 3.2 per 100,000 (95% confidence interval [CI]: 2.5. 3.9) and for females was 2.0 per 100,000 (95% CI: 1.5, 2.6). The overall age-adjusted annual incidence rate was 2.6 per 100,000 (95% CI: 2.1, 3.0). The age-adjusted incidence was highest among Maori (6.7 per 100,000, 95% CI 4.9, 8.4), followed by Pacific Island (4.4 per 100,000, 95% CI 3.2, 5.6), Asian (0.7 per 100,000, 95% CI 0.2, 1.2), and European population (0.6 per 100,000, 95% CI 0.3, 0.8). We have quantified for the first time the age-specific and age-adjusted incidence rates for plunging ranula by gender and ethnicity. The results show a likely underlying genetic predisposition for this condition, possibly with a superimposed environmental acquired factor relating to external, minor blunt trauma to the neck. 4. Laryngoscope, 126:2739-2743, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  17. Assessment of a Targeted Trap-Neuter-Return Pilot Study in Auckland, New Zealand

    PubMed Central

    Zito, Sarah; Vigeant, Shalsee; Dale, Arnja

    2018-01-01

    Simple Summary It is generally accepted that stray cats need to be managed to minimise the associated negative impacts and there is a need for effective and humane management tools. One such potential tool is trap-neuter-return (TNR), which anecdotally has been used in New Zealand to manage stray cats, but no concerted and targeted implementation of this technique has been reported, nor any formal assessments conducted. A targeted TNR (TTNR) programme for urban stray cats was implemented and assessed in one Auckland suburb. Assessment was based on the number of incoming felines; stray, unsocialised cats euthanased; unsocialised, unowned cats sterilised and returned (independently of the TTNR programme); and neonatal/underage euthanasias. Incoming stray feline, underage euthanasia, and unsocialised stray cat euthanasia numbers all reduced for the targeted suburb when these outcome measures were compared for the years before and after the programme. These outcome measures had a greater reduction in the targeted suburb compared to the other Auckland suburbs not targeted by the TTNR programme, although causation cannot be inferred, as a variety of reasons could have contributed to the changes. This pilot programme suggests that TTNR could be a valuable humane cat management tool in urban New Zealand, and further assessment is warranted. Abstract There is a need for effective and humane management tools to manage urban stray cats and minimise negative impacts associated with stray cats. One such tool is targeted trap-neuter-return (TTNR), but no concerted implementation of this technique or formal assessments have been reported. To address this deficit, a TTNR programme was implemented and assessed in one Auckland suburb from May 2015 to June 2016; the programme sterilised and returned 348 cats (4.2 cats/1000 residents). Assessment was based on the number of incoming felines; stray, unsocialised cats euthanased; unsocialised, unowned cats sterilised and returned

  18. Soil CO2 flux baseline in an urban monogenetic volcanic field: the Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Mazot, Agnès; Smid, Elaine R.; Schwendenmann, Luitgard; Delgado-Granados, Hugo; Lindsay, Jan

    2013-11-01

    The Auckland Volcanic Field (AVF) is a dormant monogenetic basaltic field located in Auckland, New Zealand. Though soil gas CO2 fluxes are routinely used to monitor volcanic regions, there have been no published studies of soil CO2 flux or soil gas CO2 concentrations in the AVF to date or many other monogenetic fields worldwide. We measured soil gas CO2 fluxes and soil gas CO2 concentrations in 2010 and 2012 in varying settings, seasons, and times of day to establish a baseline soil CO2 flux and to determine the major sources of and controlling influences on Auckland's soil CO2 flux. Soil CO2 flux measurements varied from 0 to 203 g m-2 day-1, with an average of 27.1 g m-2 day-1. Higher fluxes were attributed to varying land use properties (e.g., landfill). Using a graphical statistical approach, two populations of CO2 fluxes were identified. Isotope analyses of δ13CO2 confirmed that the source of CO2 in the AVF is biogenic with no volcanic component. These data may be used to assist with eruption forecasting in the event of precursory activity in the AVF, and highlight the importance of knowing land use history when assessing soil gas CO2 fluxes in urban environments.

  19. Metabolic syndrome prevalence in a multicultural population in Auckland, New Zealand.

    PubMed

    Gentles, Dudley; Metcalf, Patricia; Dyall, Lorna; Sundborn, Gerhard; Schaaf, David; Black, Peter; Scragg, Robert; Jackson, Rodney

    2007-01-26

    To estimate ethnic-specific metabolic syndrome prevalence in the Auckland region and to identify the main reasons for the differences. A cross-sectional survey of adults aged between 35-74 years within the Auckland area using a dual sampling frame with both cluster sampling and random selection from electoral rolls. Participants included 1006 Maori, 996 Pacific people, and 2020 of other ethnicity (mainly Europeans). The prevalence of metabolic syndrome (using the 2001 ATPIII definition, age and gender adjusted) were: Maori 32%, Pacific people 39%, and Others 16%. Maori were twice as likely as others (OR=2.01, 95% CI: 1.53 to 2.64) to have the metabolic syndrome while Pacific people were two and a half times as likely (OR=2.54, 95% CI: 1.93 to 3.35), after adjusting for multiple CVD risk factors other than the components of the syndrome. Adjusting these ethnic differences in prevalences for each of the components of the syndrome separately indicated that most of the differences could be accounted for by differences in obesity. In addition, more than a third of people with diabetes did not have the metabolic syndrome. The prevalences of metabolic syndrome were significantly higher in Pacific people and Maori compared to Others and measures of obesity accounted for most of the ethnic differences.

  20. Quantification of diabetes consultations by the main primary health care nurse groups in Auckland, New Zealand.

    PubMed

    Daly, Barbara; Arroll, Bruce; Sheridan, Nicolette; Kenealy, Timothy; Scragg, Robert

    2016-09-01

    Diabetes prevalence continues to increase, with most diabetes patients managed in primary care. This report quantifies the number of diabetes consultations undertaken by primary healthcare nurses in Auckland, New Zealand. Of 335 primary healthcare nurses randomly selected, 287 (86%) completed a telephone interview in 2006-2008. On a randomly sampled day (from the past seven) for each nurse, 42% of the nurses surveyed (n=120) consulted 308 diabetes patients. From the proportion of nurses sampled in the study, it is calculated that the number of diabetes patients consulted by primary healthcare nurses per week in Auckland between September 2006 and February 2008 was 4210, with 61% consulted by practice, 23% by specialist and 16% by district nurses. These findings show that practice nurses carry out the largest number of community diabetes consultations by nurses. Their major contribution needs to be incorporated into future planning of the community management of diabetes.

  1. Resurgence of Acanthamoeba keratitis in Auckland, New Zealand: a 7-year review of presentation and outcomes.

    PubMed

    Patel, Dipika V; Rayner, Sandra; McGhee, Charles N J

    2010-01-01

    To investigate the presentation, clinical characteristics and outcomes of Acanthamoeba keratitis (AK) in Auckland, New Zealand over a 7-year period. Retrospective analysis of all cases of AK treated by the tertiary corneal service at Auckland City Hospital/ University of Auckland Department of Ophthalmology (August 2001 to May 2008). Data were collected regarding age, gender, contact lens history, presenting signs and symptoms, diagnosis at first presentation, time to final diagnosis, identifiable risk factors, presenting and final visual acuity, results of microbiological testing, medical treatment, surgical interventions, recurrence of disease and length of follow up. All photographs and in vivo confocal microscopy images were reviewed. Twenty-five eyes of 25 patients were identified with a diagnosis of AK (mean age 40 +/- 13 years). Ninety-six per cent were contact lens wearers. Mean time to diagnosis was 41 +/- 49 days (range 0-181 days, median 21 days). Fourteen patients (56%) had been treated with topical corticosteroids prior to the diagnosis. Early diagnosis of AK (<21 days) was associated with significantly better final visual acuity and did not require any surgical intervention compared with those diagnosed at a later stage. Six patients, all in the late diagnosis group, required surgical intervention. AK has become significantly more common in New Zealand in the current decade. This study highlights the fundamental importance of early diagnosis and appropriate management in ensuring favourable outcomes. Practitioners should maintain a clinical suspicion of AK, especially as 96% of the subjects in this study were contact lens wearers.

  2. A Cross-sectional Study of Prevalence and Etiology of Childhood Visual Impairment in Auckland, New Zealand.

    PubMed

    Chong, Chee Foong; McGhee, Charles N J; Dai, Shuan

    2014-01-01

    Childhood visual impairment has significant individual and socioeconomic costs with global differences in etiology and prevalence. This study aimed to determine prevalence, etiology, and avoidable causes of childhood visual impairment in New Zealand. Retrospective data analysis from a national referral center, the Blind and Low Vision Education Network New Zealand, Auckland. The World Health Organization Program for Prevention of Blindness eye examination records for visually impaired children, 16 years or younger, registered with the Auckland Visual Resource Centre, were included. Data analyzed included demographics, etiology, visual acuity, visual fields, educational setting, and rehabilitation plan. Charts of 340 children were examined, of which 267 children (144 blind, 123 low vision) were included in the analysis, whereas the remaining 73 charts of children with no visual impairment were excluded. The calculated prevalence of blindness and low vision was 0.05% and 0.04%, respectively, in the Auckland region. Principal causes of blindness affecting 91 children (63.9%) were cerebral visual impairment in 61 children (42.4%), optic nerve atrophy in 18 children (12.5%), and retinal dystrophy in 13 children (9.0%). The main potentially avoidable causes of blindness in 27 children (19%) were neonatal trauma, asphyxia in 9 children (33%), and nonaccidental injury 6 children (22%). This first report of prevalence for childhood blindness and low vision in New Zealand is similar to data from Established Market Economy countries. The leading causes of blindness are also comparable to other high-income countries; however, proportions of avoidable causes differ significantly.

  3. Relative effects of climate and source strength on atmospheric lead concentrations in Auckland, New Zealand

    NASA Astrophysics Data System (ADS)

    Power, H. C.; de Freitas, C. R.; Hay, J. E.

    1992-06-01

    Atmospheric lead levels were examined to assess the consequences of the 46 percent reduction in the lead content of premium grade petrol in New Zealand. Since this change was implemented in July 1986 observed levels of atmospheric lead decreased by 38 percent, but all or part of this reduction may have been due to factors other than fluctuations in lead emissions, notably variations in climate. Analysis of detailed atmospheric lead, meteorological and traffic data measured contemporaneously provided insight into the atmospheric processes influencing lead levels in Auckland and formed the basis of a statistical model capable of predicting monthly lead concentrations. The model was used to predict lead levels in Auckland for the period July 1986 through to July 1989 in the absence of any reduction in the lead content of petrol. Comparison with values observed for the same period showed that all of the reduction in atmospheric lead levels since July 1986 can be attributed to the reduction in the lead content of petrol. Policy planning implications of such a finding are considered.

  4. Does periodic vehicle inspection reduce car crash injury? Evidence from the Auckland Car Crash Injury Study.

    PubMed

    Blows, Stephanie; Ivers, Rebecca Q; Connor, Jennie; Ameratunga, Shanthi; Norton, Robyn

    2003-01-01

    This paper examines the association between periodic motor vehicle inspection and frequent tire pressure checks, and the risk of car crash injury. Data were analysed from the Auckland Car Crash Injury Study, a population-based case-control study in Auckland, NZ, where vehicles are required to undergo six-monthly safety inspections. Cases were all cars involved in crashes in which at least one occupant was hospitalised or killed, which represented 571 drivers. Controls were randomly selected cars on Auckland roads (588 drivers). Participants completed a structured interview. Vehicles that did not have a current certificate of inspection had significantly greater odds of being involved in a crash where someone was injured or killed compared with cars that had a current certificate, after adjustment for age, sex, marijuana use, ethnicity and licence type (OR 3.08, 95% CI 1.87-5.05). Vehicles that had not had their tire pressure checked within the past three months also had significantly greater odds of being involved in a crash compared with those that had a tire pressure check, after adjustment for age, sex, ethnicity, seatbelt use, licence type, self-reported speed and hours per week of driving exposure (OR 1.89, 95% CI 1.16-3.08). This study provides new evidence, using rigorous epidemiological methods and controlling for multiple confounding variables, of an association between periodic vehicle inspections and three-monthly tire pressure checks and reduced risk of car crash injury. This research suggests that vehicle inspection programs should be continued where they already exist and contributes evidence in support of introducing such programs to other areas.

  5. Residential aged care in Auckland, New Zealand 1988-2008: do real trends over time match predictions?

    PubMed

    Broad, Joanna B; Boyd, Michal; Kerse, Ngaire; Whitehead, Noeline; Chelimo, Carol; Lay-Yee, Roy; von Randow, Martin; Foster, Susan; Connolly, Martin J

    2011-07-01

    in Auckland, New Zealand in 1988, 7.7% of those aged over 65 years lived in licenced residential aged care. Age-specific rates approximately doubled for each 5-year age group after the age of 65 years. Even with changes in policies and market forces since 1988, population increases are forecast to drive large growth in demand. This study shows previously unrecognised 20-year trends in rates of care in a geographically defined population. four cross-sectional surveys of all facilities (rest homes and hospitals) licenced for long-term care of older people were conducted in Auckland, New Zealand in 1988, 1993, 1998 and 2008. Facility staff completed survey forms for each resident. Numbers of licenced and occupied beds and trends in age-specific and age-standardised rates in residential aged care are reported. over the 20-year period, Auckland's population aged over 65 years increased by 43% (from 91,000 to 130,000) but actual numbers in care reduced slightly. Among those aged over 65 years, the proportion living in care facilities reduced from 1 in 13 to 1 in 18. Age-standardised rates in rest-home level care reduced from 65 to 33 per thousand, and in hospital level care, from 29 to 23 per thousand. Had rates remained stable, over 13,200 people, 74% more than observed, would have been in care in 2008. growth predicted in the residential aged care sector is not yet evident. The introduction of standardised needs assessments before entry, increased availability of home-based services, and growth in retirement villages may have led to reduced utilisation.

  6. Percutaneous endoscopic gastronomy feeding tubes: a retrospective review at Auckland Hospital 1993-4.

    PubMed

    Norrie, M W; Lane, M R

    1996-08-09

    A retrospective review of patients being treated by percutaneous endoscopic gastrostomy (PEG) at Auckland Hospital from 1993-4 was undertaken in order to determine patient characteristics, clinical outcome and to compare these results with published series. The case notes of all patients having PEGs performed in the Auckland Hospital gastroenterology unit during the defined period were reviewed. Demographic details, indications, morbidity and mortality data were obtained. Data were supplemented with information obtained from the general practitioner. Fifty procedures (18 in 1993, 32 in 1994) were performed on 41 patients (29 male 12 female), with a mean age of 61 years. Neurological disorders represented the most common clinical indication (25) followed by head and neck malignancy (9). Three patients (7) died within 30 days of the procedure and 13 (32) had early complications (less than 30 days) with four (10) having late complications. Significant pain requiring narcotics occurred in 18. Results were in general comparable to published series apart from a higher early complication rate (32% vs 16%). Pain may be significant post procedure and should be anticipated. The increasing use of this procedure in our hospital reflects its acceptability to patients, relatives and staff as a means of providing nutritional support to the patient with disorders of swallowing.

  7. Does Pukawakawa (the regional-rural programme at the University of Auckland) influence workforce choice?

    PubMed

    Matthews, Christina; Bagg, Warwick; Yielder, Jill; Mogol, Vernon; Poole, Phillippa

    2015-02-20

    Relative shortages of rural doctors persist. In 2008 the University of Auckland medical programme introduced a Year 5 regional and rural immersion programme, Pukawakawa, based in Northland, New Zealand (NZ). This study evaluates the early workforce outcomes of graduates of this programme. During 2013 we surveyed Auckland medical graduates who were in the 2008-2011 Pukawakawa cohorts. Questions were asked regarding recent and current place of work, future intentions for place of work, and career preference with reasons why. Qualitative analysis was undertaken to analyse free text responses about experiences of Pukawakawa on this choice. Of the 72 Pukawakawa participants, 45 completed the survey, for a response rate of 63%. In 2013, 62% were working in rural or regional areas, with 31% in the Northland DHB. The great majority intend to work rurally or regionally, with 35.6% intending to return to Northland DHB. Of the respondents, 68% listed general practice in their top three future career intentions. In the early postgraduate years, medical graduates who participated in Pukawakawa are very likely to be working in rural and regional areas. These graduates also show an intention to work in general practice and rural medicine.

  8. Paleointensities of the Auckland Excursion from Volcanic Rocks in New Zealand

    NASA Astrophysics Data System (ADS)

    Mochizuki, N.; Tsunakawa, H.; Shibuya, H.; Cassidy, J.; Smith, I. E.

    2001-12-01

    Shibuya et al. (1992) reported the Auckland excursion from several basaltic lava flows of monogenetic volcanic centers (<50 ka) in the Auckland Volcanic Field, New Zealand. The Auckland excursion was recorded in five centers in three intermediate direction groups of north-down, west and south. We carried out paleointensity and rock-magnetic studies in order to obtain the absolute paleointensities associated with three intermediate geomagnetic fields. Thermomagnetic analyses indicated typical Curie temperatures of 150-200, 450-500 and/or 550-580 oC. The Day plot (Day et al., 1977) showed a linear trend in the pseudo-single-domain range of magnetic carriers. Those results, combined with the reflection microscope observations, identified the magnetic carriers as titanomagnetites with wide variation in titanium content and grain size. First, the Coe's version of the Thellier method (Coe, 1967) was applied to the samples. Several samples seemed to give paleointensities ranging from 3.2 to 6.4 μ T (Shibuya and Cassidy, 1995 AGU fall meeting), but they were often affected by thermal alteration in the furnace even from fairly low temperature steps like 200oC. We were forced to introduce correction for thermal alterations in laboratory heating, using low temperature part of the Arai plot. We, therefore, applied the double heating technique (DHT) of Shaw method (Tsunakawa and Shaw, 1994), which was capable of detecting inappropriate results by the ARM correction, to the samples. The low temperature demagnetization (LTD) was combined with DHT (Yamamoto et al., submitted) before AF demagnetization and samples were heated in a vacuum of 10-100 Pa. Sixty-one samples from the five lava flows were subjected to the LTD-DHT Shaw method. Twenty-three of these samples yielded successful results passing the selection criteria. Five out of six paleointensities from the Crater Hill lava were consistent with each other. A mean paleointensity was given to be 10.9+/- 1.9 μ T (N=5) for the

  9. The role of a bus network in access to primary health care in Metropolitan Auckland, New Zealand.

    PubMed

    Rocha, C M; McGuire, S; Whyman, R; Kruger, E; Tennant, M

    2015-09-01

    Background: This study examined the spatial accessibility of the population of metropolitan Auckland, New Zealand to the bus network, to connect them to primary health providers, in this case doctors (GP) and dentists. Analysis of accessibility by ethnic identity and socio-economic status were also carried out, because of existing health inequalities along these dimensions. The underlying hypothesis was that most people would live within easy reach of primary health providers, or easy bus transport to such providers. An integrated geographic model of bus transport routes and stops, with population and primary health providers (medical. and dental practices) was developed and analysed. Although the network of buses in metropolitan Auckland is substantial and robust it was evident that many people live more than 150 metres from a stop. Improving the access to bus stops, particularly in areas of high primary health care need (doctors and dentists), would certainly be an opportunity to enhance spatial access in a growing metropolitan area.

  10. Screening for Influenza A(H1N1)pdm09, Auckland International Airport, New Zealand

    PubMed Central

    Hale, Michael J.; Baker, Michael G.

    2012-01-01

    Entry screening for influenza A(H1N1)pdm09 at Auckland International Airport, New Zealand, detected 4 cases, which were later confirmed, among 456,518 passengers arriving April 27–June 22, 2009. On the basis of national influenza surveillance data, which suggest that ≈69 infected travelers passed through the airport, sensitivity for screening was only 5.8%. PMID:22516105

  11. Behavioural science at the Auckland Medical School: introduction and evaluation of a revised programme.

    PubMed

    Raeburn, J M; Dubignon, J M; Grant, V J; Richmond, D E

    1989-12-13

    This paper provides an overview of developments in the Auckland Medical School behavioural science programme. From 1984 to 1987, an entirely new five year course was phased in, its design based on a survey of 165 clinical teachers. This course has eight topic streams oriented towards producing a behaviourally knowledgeable and skilled clinician. Evaluation of the course shows good acceptance by students. Recent and planned modifications to the course are described.

  12. Sedimentology, eruptive mechanism and facies architecture of basaltic scoria cones from the Auckland Volcanic Field (New Zealand)

    NASA Astrophysics Data System (ADS)

    Kereszturi, Gábor; Németh, Károly

    2016-09-01

    Scoria cones are a common type of basaltic to andesitic small-volume volcanoes (e.g. 10- 1-10- 5 km3) that results from gas-bubble driven explosive eruptive styles. Although they are small in volume, they can produce complex eruptions, involving multiple eruptive styles. Eight scoria cones from the Quaternary Auckland Volcanic Field in New Zealand were selected to define the eruptive style variability from their volcanic facies architecture. The reconstruction of their eruptive and pyroclastic transport mechanisms was established on the basis of study of their volcanic sedimentology, stratigraphy, and measurement of their pyroclast density, porosity, Scanning Electron Microscopy, 2D particle morphology analysis and Visible and Near Visible Infrared Spectroscopy. Collection of these data allowed defining three end-member types of scoria cones inferred to be constructed from lava-fountaining, transitional fountaining and Strombolian type, and explosive Strombolian type. Using the physical and field-based characteristics of scoriaceous samples a simple generalised facies model of basaltic scoria cones for the AVF is developed that can be extended to other scoria cones elsewhere. The typical AVF scoria cone has an initial phreatomagmatic phases that might reduce the volume of magma available for subsequent scoria cone forming eruptions. This inferred to have the main reason to have decreased cone volumes recognised from Auckland in comparison to other volcanic fields evolved dominantly in dry eruptive condition (e.g. no external water influence). It suggests that such subtle eruptive style variations through a scoria cone evolution need to be integrated into the hazard assessment of a potentially active volcanic field such as that in Auckland.

  13. Corneal Transplantation in Auckland, New Zealand, 1999-2009: Indications, Patient Characteristics, Ethnicity, Social Deprivation, and Access to Services.

    PubMed

    Crawford, Alexandra Z; McKelvie, James; Craig, Jennifer P; McGhee, Charles N J; Patel, Dipika V

    2017-05-01

    To analyze characteristics and indications for corneal transplantation in patients undergoing penetrating, lamellar, and endothelial keratoplasty in Auckland, New Zealand (NZ). Corneal transplantation data from the NZ National Eye Bank and hospital records of corneal transplant recipients in the Auckland region from January 1, 2000, to December 31, 2009, were collated. Patient demographics, preoperative diagnosis, indication, ocular and medical history, visual acuity, deprivation index, and access to transplantation surgery were analyzed. A total of 941 corneal transplants involving 770 patients were included for analysis. Mean age was 46 years. Age and ethnicity varied according to the transplant indication. A male preponderance and disproportionally high rates of Māori and Pacific ethnicity with a mean age of 30 years were observed in transplants for keratoconus. A total of 67.2% of corneal transplants were completed in the public health system and were associated with higher levels of deprivation than those completed in private facilities. Preoperative visual acuity varied according to the transplant type and indication. The most common clinical indication for corneal transplantation was keratoconus (41.3%), followed by repeat transplantation (21.0%). There was no significant change in the relative proportion of transplant indications in any year over the duration of this study (P = 0.41). A contralateral corneal transplant was present in 24.4% and glaucoma in 12.8% of penetrating keratoplasty recipients. Keratoconus is the leading indication for corneal transplantation in Auckland, NZ, and involves a disproportionately high rate of Māori and Pacific transplant recipients with a male preponderance and comparatively low mean age at the time of surgery.

  14. The health status of asylum seekers screened by Auckland Public Health in 1999 and 2000.

    PubMed

    Hobbs, Mark; Moor, Catherine; Wansbrough, Tony; Calder, Lester

    2002-08-23

    Approximately 1500 to 1800 applications for refugee status are made to the New Zealand Immigration Service each year. Approximately one third of these asylum seekers receive health screening from Auckland Public Health. We report here key findings from this screening programme for the period 1999 to 2000. The files of patients attending the Auckland Public Health Protection Asylum Seekers Screening Clinic at Green Lane Hospital were reviewed. Data on demographics, medical examination, diagnostic testing and referrals were analysed. Nine hundred people, mainly from Middle Eastern countries, received screening. Important findings were: symptoms of psychological illness (38.4%); Mantoux skin test positivity ( 36.4%); active tuberculosis (0.6%); TB infection requiring chemoprophylaxis (18%) or chest X-ray monitoring (15%); gut parasite infection; carrier state for alpha and beta thalassaemia and the heterozygous states for HbS and HbE; incomplete immunisation; and the need for referral to a secondary care service (32.6%). Immigrant communities in New Zealand have special healthcare needs, as well as experiencing language barriers, cultural differences and economic difficulties. Healthcare providers should be alert to these needs. Appropriate resources are required to address these issues in a timely fashion.

  15. Prevalence of vitamin D deficiency among patients attending a general otolaryngology clinic in South Auckland.

    PubMed

    Bartley, Jim; Reid, David; Morton, Randall P

    2009-05-01

    We performed a prospective observational study to estimate the prevalence of vitamin D deficiency in patients attending a general otolaryngology clinic in South Auckland, New Zealand. From July 21,2008, to August 7, 2008, all new patients presenting to otolaryngology clinics at which one of the authors (D.R.) was present had their vitamin D status assessed by measurement of their plasma 25-hydroxyvitamin D [25(OH)D] level. Of 48 patients, 2% had 25(OH)D levels of 17.5 nmol/L or less (a level associated with osteomalacia), 58% had 25(OH)D levels of 50 nmol/L or less (a level associated with vitamin D deficiency), and 100% had 25(OH)D levels of 80 nmol/L or less. Most of the patients attending a general otolaryngology clinic in South Auckland are vitamin D-deficient. It is unclear whether low vitamin D levels are associated more directly with otolaryngological disorders or skin type, because the small size of this study and the broad range of conditions seen precluded a meaningful statistical analysis. Further research into the relationship of vitamin D to specific otolaryngological presentations is required.

  16. Urinalysis requests on the elderly residing in the Auckland community: tick box requesting?

    PubMed

    Upton, Arlo; McEwan, M; Williamson, Deborah

    2016-01-29

    Urinalysis for microscopy and culture is one of the most frequently requested tests for microbiology laboratories, particularly from elderly patients. This study sought to describe the clinical appropriateness of urinalysis from community-dwelling elderly patients and subsequent antibiotic prescription. Demographic, laboratory, and antibiotic prescription data were collected on all samples submitted from patients ≥ 70 years during August 2014 to Labtests Auckland. In addition, clinical data were collected by questionnaire from a subgroup of 200 patients. During August 2014, approximately 7% of the Auckland population aged ≥ 70 years had urinalysis submitted. Urine dipstick was not routinely performed before specimen submission, particularly from patients living at home rather than a long-term care facility, and nearly 50% of samples were not cultured due to absence of pyuria. Escherichia coli was isolated from 23% of female and 7% of male specimens. E. coli isolates from our cohort were less susceptible to all antibiotics tested against compared with all E. coli isolated from all urines in 2014. Clinical indications were absent in 40% of the subgroup of patients. Antibiotic prescription within 7 days of urinalysis was common (36%). This study highlights the frequency of urinalysis testing among the elderly residing in the community. Clinical indications are often absent, and treatment of asymptomatic bacteriuria is likely to be contributing to excessive antibiotic prescription in this group of patients.

  17. Assessment of a Targeted Trap-Neuter-Return Pilot Study in Auckland, New Zealand.

    PubMed

    Zito, Sarah; Aguilar, Glenn; Vigeant, Shalsee; Dale, Arnja

    2018-05-13

    There is a need for effective and humane management tools to manage urban stray cats and minimise negative impacts associated with stray cats. One such tool is targeted trap-neuter-return (TTNR), but no concerted implementation of this technique or formal assessments have been reported. To address this deficit, a TTNR programme was implemented and assessed in one Auckland suburb from May 2015 to June 2016; the programme sterilised and returned 348 cats (4.2 cats/1000 residents). Assessment was based on the number of incoming felines; stray, unsocialised cats euthanased; unsocialised, unowned cats sterilised and returned (independently of the TTNR programme); and neonatal/underage euthanasias. Incoming stray felines, underage euthanasias, and unsocialised stray cat euthanasias were all reduced for the targeted suburb when compared for the years before and after the programme (the percentage reduction in these parameters was −39, −17, −34, −7, and −47, respectively). These outcome measures had a greater reduction in the targeted suburb compared to the Auckland suburbs not targeted by the TTNR programme ( p < 0.01), although causation cannot be inferred, as a variety of reasons could have contributed to the changes. This pilot programme suggests that TTNR could be a valuable, humane cat management tool in urban New Zealand, and further assessment is warranted.

  18. Birth outcomes for women using free-standing birth centers in South Auckland, New Zealand.

    PubMed

    Bailey, David John

    2017-09-01

    This study investigates maternal and perinatal outcomes for women with low-risk pregnancies laboring in free-standing birth centers compared with laboring in a hospital maternity unit in a large New Zealand health district. The study used observational data from 47 381 births to women with low-risk pregnancies in South Auckland maternity facilities 2003-2010. Adjusted odds ratios with 95% confidence intervals were calculated for instrumental delivery, cesarean section, blood transfusion, neonatal unit admission, and perinatal mortality. Labor in birth centers was associated with significantly lower rates of instrumental delivery, cesarean section and blood transfusion compared with labor in hospital. Neonatal unit admission rates were lower for infants of nulliparous women laboring in birth centers. Intrapartum and neonatal mortality rates for birth centers were low and were not significantly different from the hospital population. Transfers to hospital for labor and postnatal complications occurred in 39% of nulliparous and 9% of multiparous labors. Risk factors identified for transfer were nulliparity, advanced maternal age, and prolonged pregnancy ≥41 weeks' gestation. Labor in South Auckland free-standing birth centers was associated with significantly lower maternal intervention and complication rates than labor in the hospital maternity unit and was not associated with increased perinatal morbidity. © 2017 Wiley Periodicals, Inc.

  19. A model for calculating eruptive volumes for monogenetic volcanoes — Implication for the Quaternary Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Kereszturi, Gábor; Németh, Károly; Cronin, Shane J.; Agustín-Flores, Javier; Smith, Ian E. M.; Lindsay, Jan

    2013-10-01

    Monogenetic basaltic volcanism is characterised by a complex array of behaviours in the spatial distribution of magma output and also temporal variability in magma flux and eruptive frequency. Investigating this in detail is hindered by the difficulty in evaluating ages of volcanic events as well as volumes erupted in each volcano. Eruptive volumes are an important input parameter for volcanic hazard assessment and may control eruptive scenarios, especially transitions between explosive and effusive behaviour and the length of eruptions. Erosion, superposition and lack of exposure limit the accuracy of volume determination, even for very young volcanoes. In this study, a systematic volume estimation model is developed and applied to the Auckland Volcanic Field in New Zealand. In this model, a basaltic monogenetic volcano is categorised in six parts. Subsurface portions of volcanoes, such as diatremes beneath phreatomagmatic volcanoes, or crater infills, are approximated by geometrical considerations, based on exposed analogue volcanoes. Positive volcanic landforms, such as scoria/spatter cones, tephras rings and lava flow, were defined by using a Light Detection and Ranging (LiDAR) survey-based Digital Surface Model (DSM). Finally, the distal tephra associated with explosive eruptions was approximated using published relationships that relate original crater size to ejecta volumes. Considering only those parts with high reliability, the overall magma output (converted to Dense Rock Equivalent) for the post-250 ka active Auckland Volcanic Field in New Zealand is a minimum of 1.704 km3. This is made up of 1.329 km3 in lava flows, 0.067 km3 in phreatomagmatic crater lava infills, 0.090 km3 within tephra/tuff rings, 0.112 km3 inside crater lava infills, and 0.104 km3 within scoria cones. Using the minimum eruptive volumes, the spatial and temporal magma fluxes are estimated at 0.005 km3/km2 and 0.007 km3/ka. The temporal-volumetric evolution of Auckland is

  20. Ethnic differences in Type 2 diabetes care and outcomes in Auckland: a multiethnic community in New Zealand.

    PubMed

    Robinson, Tom; Simmons, David; Scott, David; Howard, Eileen; Pickering, Karen; Cutfield, Rick; Baker, John; Patel, Ashwin; Wellingham, John; Morton, Sara

    2006-06-02

    In New Zealand, Maori and Pacific (mostly of Samoan, Tongan, Niuean, or Cook Islands origin) people with Type 2 diabetes are more likely to suffer poor outcomes than other New Zealanders. Responsibility for addressing this outcome differential is falling on primary care and general practice in particular. This paper compares the general practice care provided to people with Type 2 diabetes in South and West Auckland, according to ethnicity. An external audit of general practice diabetes care is carried out in South and West Auckland by the Diabetes Care Support Service. The results of 5917 routine patient audits carried out in 2003 are included in this study. Number of visits, recording of important information, risk factors, and treatments are compared between different ethnic groups. Maori and Pacific people with diabetes who attend a regular GP had a higher average number of consultations than Europeans (5.7, 5.4, and 4.8 visits per year respectively). They were as likely as Europeans to have undergone important regular examinations and investigations. Maori were more likely than Europeans to be on some treatments. However, Maori and Pacific people were more likely to have a range of adverse risk factors for diabetes complications than Europeans. These include being a smoker (35, 18, and 13% respectively), having an HbA1c greater than 8% (50, 56, 23%), and having microalbuminuria (55, 50, 27%). Although there were no large differences in the process measures of general practice diabetes care provided to different ethnic groups in South and West Auckland, Maori and Pacific people were not achieving the same outcomes of care in terms of risk factors for diabetes complications. Many of these risk factors are influenced by other factors in the wider community; however the New Zealand health system needs to consider how it can better address these differences.

  1. Orbital fractures treated in Auckland from 2010-2015: review of patient outcomes.

    PubMed

    Anand, Lanit; Sealey, Christopher

    2017-07-07

    The purpose of this study was to review patient outcomes from surgical reconstruction of isolated orbital fractures, performed by the Auckland District Health Board (ADHB) Oral and Maxillofacial Surgery service (OMFS), from 2010 to 2015. In particular, we wished to assess titanium as an orbital reconstructive material and compare outcomes with the international literature. Hospital records for 103 adults (>18 years old) who underwent repair of isolated orbital fractures by the OMFS department at Middlemore Hospital, between 2010 and 2015, were reviewed. Information collected included patient characteristics, cause of injury, type of reconstruction material used and post-operative complications. Patients were then followed up by means of a verbal telephone questionnaire. The majority of patients were male in the 18-30 year age group, with interpersonal violence being the leading cause of injury. Titanium was the preferred choice of reconstructive material. Seven patients required return to theatre to resolve post-operative complications. Sixty-four patients could be contacted by telephone (12 months to six years follow-up). Thirty patients, who could not be contacted by telephone, did attend clinic follow-up and were assessed from their hospital records (minimum of one month follow-up). Ten patients could not be contacted by telephone and had not attended clinic follow-up. Problems with diplopia, paraesthesia and cosmesis were within complication rates reported in the literature. Patients with isolated orbital fractures, treated by the Oral and Maxillofacial Surgery Department in Auckland from 2010-2015, were reviewed. Titanium was the most commonly used reconstructive material and proved to be well tolerated. Complication rates were within international norms.

  2. A psychometric evaluation of the University of Auckland General Practice Report of Educational Environment: UAGREE.

    PubMed

    Eggleton, Kyle; Goodyear-Smith, Felicity; Henning, Marcus; Jones, Rhys; Shulruf, Boaz

    2017-03-01

    The aim of this study was to develop an instrument (University of Auckland General Practice Report of Educational Environment: UAGREE) with robust psychometric properties that measured the educational environment of undergraduate primary care. The questions were designed to incorporate measurements of the teaching of cultural competence. Following a structured consensus process and an initial pilot, a list of 55 questions was developed. All Year 5 and 6 students completing a primary care attachment at Auckland University were invited to complete the questionnaire. The results were analysed using exploratory factor analysis and confirmatory factor analysis resulting in a 16-item instrument. Three factors were identified explaining 53% of the variance. The items' reliability within the factors were high (Learning: 0.894; Teaching: 0.871; Cultural competence: 0.857). Multiple groups analysis by gender; and separately across ethnic groups did not find significant differences between groups. UAGREE is a specific instrument measuring the undergraduate primary care educational environment. Its questions fit within established theoretical educational environment frameworks and the incorporation of cultural competence questions reflects the importance of teaching cultural competence within medicine. The psychometric properties of UAGREE suggest that it is a reliable and valid measure of the primary care education environment.

  3. Methodology of a population-based stroke and TIA incidence and outcomes study: the Auckland Regional Community Stroke Study (ARCOS IV) 2011-2012.

    PubMed

    Krishnamurthi, Rita; Jones, Amy; Barber, P Alan; Barker-Collo, Suzanne; McPherson, Kathryn; Bennett, Derrick; Rush, Elaine; Suh, Flora; Starkey, Nicola; Theadom, Alice; Parag, Varsha; Rathnasabapathy, Yogini; Feigin, Valery L

    2014-01-01

    Stroke is a leading cause of death and disability worldwide. Stroke burden is immense as it leads to premature deaths, leaves survivors with ongoing disabilities, and has a major financial impact on the individual, their families, and the community. Reliable, high-quality evidence is needed on stroke risk factors, incidence, and outcomes to provide information on how best to reduce this burden. Population-based studies are regarded as the 'gold-standard' of measuring disease burden but are not common due to the logistical and financial challenges they present. The Auckland Regional Community Stroke Studies are among a few in the world that have been carried out at a population level and at regular intervals. The aim of the fourth Auckland Regional Community Stroke Studies IV is to examine the current measures of stroke incidence, prevalence, and outcomes as well the trends over four decades. This article describes the methodology of the Auckland Regional Community Stroke Studies IV with stroke and transient ischemic attacks cases registered over a 12-month period from March 1, 2011 to February 29, 2012. The methodology described may be used as a guide in order to design similar population-based stroke incidence and outcome studies in other countries and populations, thus facilitating the collection of most consistent and accurate stroke epidemiological data. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.

  4. The prevalence of depression among Maori patients in Auckland general practice.

    PubMed

    Arroll, Bruce; Goodyear-Smith, Felicity; Kerse, Ngaire; Hwang, Melanie; Crengle, Susan; Gunn, Jane; Fishman, Tana; Hatcher, Simon; Pradhan, Sanat; Sidhu, Karishma

    2009-03-01

    There has been concern over high rates of mental illness in Maori. Previous studies in general practice have had small sample sizes. To determine the prevalence of major depression among Maori patients in Auckland general practice using the CIDI and the PHQ as measurement tools. This prevalence study is part of a larger randomised trial. The patients were recruited from 77 general practitioners from around Auckland who could provide a private room for interviewing. The patients were invited to participate in the waiting room and all consecutive patients were approached. For this study all patients received a computerised CIDI examination and one third received a PHQ assessment prior to getting the CIDI. The interviewer was blind to the questionnaire results when the patient did the CIDI. There were 7994 patients approached from whom there were data on 7432. The prevalence of Maori in the study was 9.7%. The overall 12-month prevalence of major depression based on the CIDI was 10.1% 95% CI (8.8 to 11.4). For Maori the prevalence was 11.5% 95% CI (8.8 to 14.2) and for non-Maori 10.1% 95% CI (8.6 to 11.3). For Maori men and Maori women the prevalence was 8.5% and 13.4% and for non-Maori men and non-Maori women it was 8.3% and 11.1%. The prevalence of depression over at least the previous two weeks on the PHQ > or = 9 for all participants was 12.9% 95% CI (11.2 to 14.5). The prevalence of depression among Maori is high, but not as high as earlier studies. This may be due to the bigger sample size of this study.

  5. Late Glacial and Holocene Climate Change in the subantarctic Auckland Islands

    NASA Astrophysics Data System (ADS)

    Gilmer, G.; Moy, C. M.; Vandergoes, M.; Gadd, P.; Riesselman, C. R.; Jacobsen, G. E.; Wilson, G. S.; Visinand, C.

    2017-12-01

    Situated within the core of the Southern Hemisphere westerly winds, and between the subtropical and subantarctic fronts, the New Zealand subantarctic islands are uniquely positioned to evaluate past ocean and atmospheric change in the middle to high southern latitudes. We collected a series of sediment cores from Auckland Island fjords to produce a high-resolution record of climate change following the Last Glacial Maximum. Physical property and organic geochemical data, Itrax XRF, and visual core descriptions indicate the cores capture several phases of sedimentation. From these studies, we identify four primary sedimentary facies: 1) a deglacial facies exhibiting mm-scale laminae defined by magnetic susceptibility and density contrasts and high counts of elements associated with terrigenous sources; 2) a lacustrine facies defined by very low density, high organic carbon concentrations and low counts of lithophilic elements; 3) a marine transgression facies with moderate density, moderate bioturbation and alternating marine and lacustrine sedimentary components; 4) a marine facies that contains biogenic carbonate. Radiocarbon results indicate deglacial sedimentation was underway in the basin by approximately 19,000 cal yr BP. Lacustrine deposition in ice-free conditions began around 15,600 cal yr BP and continued until marine transgression at approximately 9,500 cal yr BP. During the early Holocene between 11 and 9.5 ka, we observe elevated n-alkane δD values and an overall increase in redox-sensitive elements that signal a combination of warmer atmospheric temperatures and reduced westerly wind strength that drives fjord stratification. Poleward-shifted westerlies south of the Auckland Islands could accommodate these results, but there are few records to corroborate this interpretation. We will discuss these results within the context of developing New Zealand and subantarctic paleoclimate records in order to provide a more comprehensive record of past change.

  6. Activating Built Pedagogy: A Genealogical Exploration of Educational Space at the University of Auckland Epsom Campus and Business School

    ERIC Educational Resources Information Center

    Locke, Kirsten

    2015-01-01

    Inspired by a new teaching initiative that involved a redesign of conventional classroom spaces at the University of Auckland's Epsom Campus, this article considers the relationship between architecture, the built environment and education. It characterises the teaching space of the Epsom Campus as the embodiment of educational policy following…

  7. Tau Fifine Fiafia: the binge drinking behaviours of nine New Zealand born Niuean women living in Auckland.

    PubMed

    Gray, Josephine; Nosa, Vili

    2009-02-01

    The aim of this paper is to explore the binge drinking behaviours and attitudes of nine New Zealand born Niuean women aged 18 to 45 plus years living in Auckland who are heavy binge drinkers. Taped interviews were conducted individually with nine Niuean participants, utilising a semi-structured interviewing schedule in both Niuean and English languages. This study argues that excessive drinking style of binge drinking commonly practised with the younger generation of Niuean women. The study highlighted the important role of supportive friends and women within a drinking circle compared to the cultural and gender restrictions when drinking with males. NZ born Niuean women outlined there were fewer limitations on alcohol use and behaviour associated with drunkenness; the reason for drinking was to reach a level of intoxication. Alcohol consumption was seen as a way of socialising, having fun, being happy and feeling safe primarily when drinking with other women, even though participants experienced negative behaviour when safety was threatened. The Niuean community needs to address alcohol related issues affecting Niuean women through education awareness within social and cultural gatherings. This study is not a representative study and it cannot be generalised to all New Zealand born Niuean women because the sampling size is too small. The aim of this paper is to look at the binge drinking behaviours of nine New Zealand born Niuean women living in Auckland. A qualitative research methodology offace to face interviews was used to interview NZ born Niuean women and their alcohol consumption. Participants were recruited by using a snow ball methodology. Participants were also approached throughout the community on the telephone and via email/internet about the research. Participants were also from Niuean gatherings such as Niuean cultural workshops, weaving groups, church groups, and sports groups, Niuean websites. A semi-structured interview format was used making it

  8. Trends in ethnic disparities in stroke incidence in Auckland, New Zealand, during 1981 to 2003.

    PubMed

    Carter, Kristie; Anderson, Craig; Hacket, Maree; Feigin, Valery; Barber, P Alan; Broad, Joanna B; Bonita, Ruth

    2006-01-01

    Although geographical variations in stroke rates are well documented, limited data exist on temporal trends in ethnic-specific stroke incidence. We assessed trends in ethnic-specific stroke rates using standard diagnostic criteria and community-wide surveillance procedures in Auckland, New Zealand (NZ) in 1981 to 1982, 1991 to 1992, and 2002 to 2003. Indirect and direct methods were used to adjust first-ever (incident) and total (attack) rates for changes in the structure of the population and reported with 95% CIs. Ethnicity was self-defined and categorized as "NZ/European," "Maori," "Pacific peoples," and "Asian and other." Stroke attack (19%; 95% CI, 11% to 26%) and incidence rates (19%; 95% CI, 12% to 24%) declined significantly in NZ/Europeans from 1981 to 1982 to 2002 to 2003. These rates remained high or increased in other ethnic groups, particularly for Pacific peoples in whom stroke attack rates increased by 66% (95% CI; 11% to 225%) over the periods. Some favorable downward trends in vascular risk factors, such as cigarette smoking, were counterbalanced by increasing age, body mass index, and diabetes in certain ethnic groups. Divergent trends in ethnic-specific stroke incidence and attack rates, and of associated risk factors, have occurred in Auckland over recent decades. The findings provide mixed views as to the future burden of stroke in populations undergoing similar lifestyle and structural changes.

  9. Incidence, Risk Factors, and Outcomes of Panton-Valentine Leukocidin-Positive Methicillin-Susceptible Staphylococcus aureus Infections in Auckland, New Zealand ▿

    PubMed Central

    Muttaiyah, S.; Coombs, G.; Pandey, S.; Reed, P.; Ritchie, S.; Lennon, D.; Roberts, S.

    2010-01-01

    Panton-Valentine leukocidin (PVL) has been linked to invasive community-acquired methicillin-resistant Staphylococcus aureus infections. However, the association between disease and PVL-positive methicillin-susceptible Staphylococcus aureus (MSSA) has not been widely reported. We aimed to examine the epidemiology of PVL in clinical MSSA isolates from patients presenting to Auckland City Hospital. Four hundred eleven MSSA clinical isolates and 93 nasal carriage isolates were collected and tested for the presence of the lukSF-PV genes using PCR. The results were examined in light of host and disease factors. Multilocus sequence typing (MLST) was performed on a random subset of isolates to ensure that there was no single PVL-positive MSSA clone responsible for disease in Auckland. The prevalence of the lukSF-PV genes in MSSA isolates associated with disease (124/335; 37%) was not significantly different from the prevalence of the lukSF-PV genes in MSSA nasal carriage isolates (29/93; 31% [P = 0.33]). PVL-positive MSSA isolates in Auckland are genetically diverse and come from a number of different clonal complexes. PVL-positive infections peaked at between 10 and 20 years of age, with a subsequent decline. Pacific ethnicity, age, diagnosis of skin and soft tissue infection (SSTI), community-onset infection, and the need for surgical intervention were found by multivariate analysis to be independently associated with PVL-positive MSSA infection. More than one-third of MSSA infections in our patient population are caused by PVL-positive strains. Those patients with PVL-positive MSSA infection were more likely to be of Pacific ethnicity, be younger in age, have community-onset infection, have SSTI, and need surgical intervention. PMID:20686081

  10. Type 2 diabetes in young adults in Central Auckland: demography and complications.

    PubMed

    Beig, Junaid; Khanolkar, Manish; Cundy, Tim

    2018-01-01

    Type 2 diabetes (T2D) in young adults is associated with a high risk of diabetes complications. To investigated the demography and the emergence of complications of young adults with T2D in the central Auckland region where there has been substantial immigration. In total, 310 young adults with T2D (<40 years) were registered with the Auckland Diabetes Centre in 2015. We documented demographic, anthropometric and metabolic variables and prevalence and the emergence of complications. Three demographic groups accounted for 243 participants (78%): 135 (44%) were migrants of Asian or Pacific Island origin, diagnosed a median 9 years after migration at a mean age of 28 ± 6 years; 88 (29%) were New Zealand-born Pāsifika descent, with a high prevalence of morbid obesity and 37 (12%) had major mental illness or intellectual disability. At diagnosis, the median HbA1c was 80 mmol/mol, and in 28%, it was ≥100 mmol/mol. A median 6 years after diagnosis, 56% had some degree of retinopathy, with the prevalence related both to the duration of diabetes and glycaemic control (P = 0.001). Forty-four percent of subjects had abnormal albuminuria at diagnosis (12% with macroalbuminuria). Increased albuminuria was strongly associated with obesity (P = 0.002). The development of CKD stages 4-5 was related both to the severity of retinopathy and degree of albuminuria at diagnosis (P = 0.0001). Major cardiovascular events were related to the severity of retinopathy at diagnosis (P = 0.0001). New migrants, New Zealand-born Pāsifika and patients with mental illness or an intellectual disability comprise the bulk of young onset T2D. The disease is aggressive, and by the age of 40, patients are already developing advanced complications. © 2017 Royal Australasian College of Physicians.

  11. Towards real-time eruption forecasting in the Auckland Volcanic Field: application of BET_EF during the New Zealand National Disaster Exercise `Ruaumoko'

    NASA Astrophysics Data System (ADS)

    Lindsay, Jan; Marzocchi, Warner; Jolly, Gill; Constantinescu, Robert; Selva, Jacopo; Sandri, Laura

    2010-03-01

    The Auckland Volcanic Field (AVF) is a young basaltic field that lies beneath the urban area of Auckland, New Zealand’s largest city. Over the past 250,000 years the AVF has produced at least 49 basaltic centers; the last eruption was only 600 years ago. In recognition of the high risk associated with a possible future eruption in Auckland, the New Zealand government ran Exercise Ruaumoko in March 2008, a test of New Zealand’s nation-wide preparedness for responding to a major disaster resulting from a volcanic eruption in Auckland City. The exercise scenario was developed in secret, and covered the period of precursory activity up until the eruption. During Exercise Ruaumoko we adapted a recently developed statistical code for eruption forecasting, namely BET_EF (Bayesian Event Tree for Eruption Forecasting), to independently track the unrest evolution and to forecast the most likely onset time, location and style of the initial phase of the simulated eruption. The code was set up before the start of the exercise by entering reliable information on the past history of the AVF as well as the monitoring signals expected in the event of magmatic unrest and an impending eruption. The average probabilities calculated by BET_EF during Exercise Ruaumoko corresponded well to the probabilities subjectively (and independently) estimated by the advising scientists (differences of few percentage units), and provided a sound forecast of the timing (before the event, the eruption probability reached 90%) and location of the eruption. This application of BET_EF to a volcanic field that has experienced no historical activity and for which otherwise limited prior information is available shows its versatility and potential usefulness as a tool to aid decision-making for a wide range of volcano types. Our near real-time application of BET_EF during Exercise Ruaumoko highlighted its potential to clarify and possibly optimize decision-making procedures in a future AVF eruption

  12. Early outcome of patients undergoing transcatheter aortic valve implantation (TAVI): The Auckland City Hospital experience 2011-2015.

    PubMed

    Wu, Sylvia S Y; Wang, Tom Kai Ming; Nand, Parma; Ramanathan, Tharumenthiran; Webster, Mark; Stewart, Jim

    2016-01-08

    Transcatheter aortic valve implantation (TAVI) is an alternative to surgical aortic valve replacement (AVR) in high-risk patients. We report the initial TAVI experience at Auckland City Hospital. The records of patients undergoing TAVI between 2011 and 2015 at Auckland City Hospital were reviewed. We report the procedural success and outcome, including major adverse events (death, stroke, myocardial infarction, bleeding, vascular complications and rehospitalisations), degree of aortic regurgitation and symptom status up to 1-year follow-up. Mean age was 80.7 years and mean Euroscore II and Society of Thoracic Surgeons' scores were 8.2% and 6.3% respectively; 50% had undergone previous cardiac surgery. Successful deployment of the valve was achieved in all patients. The cumulative mortality rates at 30 days, 6 months and 1 year were 2.4%, 6.1% and 12.2% and cumulative stroke rates 1.2%, 3% and 8.2% respectively. Severe aortic regurgitation occurred in 2.3% TAVI is available in the New Zealand public hospital system for patients who are high-risk candidates for AVR. Early results are excellent and indicate that the technology is being used appropriately, according to current access criteria. If the early cost effectiveness data are confirmed, the indications for TAVI may widen.

  13. The Auckland experience with laparoscopic donor nephrectomy.

    PubMed

    Muthu, Carl; McCall, John; Windsor, John; Harman, Richard; Dittmer, Ian; Smith, Pat; Munn, Stephen

    2003-07-25

    To examine the initial experience of laparoscopic donor nephrectomy (LDN) in New Zealand and compare it with open donor nephrectomy (ODN). All LDNs performed between June 2000 and June 2002 were reviewed. An equal number of ODNs were reviewed. Data were also collected on the recipients of the grafts. Key clinical data were prospectively collected; remaining data were collected by retrospectively reviewing patient charts. Auckland Hospital databases were accessed for costing analysis. Thirty five cases of each procedure had been performed. There has been 100% LDN graft survival. There was no significant difference in graft function (serum creatinine) at one and 12 months (p = 0.25 and 0.35) between the two groups. There was no significant difference in donor morbidity (26% vs 31%, p = 0.59). LDN resulted in a shorter hospital stay (3 vs 6.5 days, p <0.0001) and convalescence period (3 vs 6 weeks, p <0.0001). LDN was significantly more expensive (13 357 dollars vs 6713 dollars, p <0.0001). LDN in the New Zealand setting provides effective grafts for renal transplant recipients and is safe for the donor. Advantages for the donor are a shorter hospital stay and convalescence period. The major disadvantage of LDN is its higher cost compared with ODN.

  14. Brain abscess in the computed tomography era: A 10-year experience from Auckland, New Zealand

    PubMed Central

    Holland, DJ; Cooper, B; Garner, J; Ellis-Pegler, R; Mee, E

    1993-01-01

    Notes were reviewed for 68 patients with brain abscess diagnosed at Auckland Hospital, Auckland, New Zealand between 1978 and 1988. Mean age was 30 years (range one week to 74 years). There were 48 men and 40% were Maori or Pacific Island Polynesians. Seventy-two per cent of patients had headache, 54% had fever and 72% had lateralizing neurological signs. Thirty-one per cent of abscesses were associated with contiguous infection (otic, sinus, dental). Forty-four per cent were in the frontal lobe. Two abscesses were sterile; 197 bacterial isolates were cultured from the remainder. Fifty-four per cent contained obligate anaerobes, which were the only isolates in 22%. Streptococcus anginosus was the single most common isolate present in 22% of the abscesses. Amoxycillin plus metronidazole provided cover for approximately 95% of the total isolates on the basis of sensitivity testing. Treatment was with surgery and antibiotics in all but three patients, who were cured with antibiotics alone. Sixty per cent had a definitive regimen of penicillin (or ampicillin/amoxycillin) and/or metronidazole, always intravenous initially but subsequently often orally. Median duration of antibiotic treatment was 57 days (range 28 to 206). Seventy-five per cent had initial aspiration, 9% open drainage and 7% were excised initially. Seventy-one per cent had a good functional outcome. Mortality was 8.8%. Factors associated with a poor outcome were trauma as a cause, and delays after admission of more than seven days to diagnosis and/or operation. PMID:22346451

  15. Tools and techniques for developing tephra stratigraphies in lake cores: A case study from the basaltic Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Hopkins, Jenni L.; Millet, Marc-Alban; Timm, Christian; Wilson, Colin J. N.; Leonard, Graham S.; Palin, J. Michael; Neil, Helen

    2015-09-01

    Probabilistic hazard forecasting for a volcanic region relies on understanding and reconstructing the eruptive record (derived potentially from proximal as well as distal volcanoes). Tephrostratigraphy is commonly used as a reconstructive tool by cross-correlating tephra deposits to create a stratigraphic framework that can be used to assess magnitude-frequency relationships for eruptive histories. When applied to widespread rhyolitic deposits, tephra identifications and correlations have been successful; however, the identification and correlation of basaltic tephras are more problematic. Here, using tephras in drill cores from six maars in the Auckland Volcanic Field (AVF), New Zealand, we show how X-ray density scanning coupled with magnetic susceptibility analysis can be used to accurately and reliably identify basaltic glass shard-bearing horizons in lacustrine sediments and which, when combined with the major and trace element signatures of the tephras, can be used to distinguish primary from reworked layers. After reliably identifying primary vs. reworked basaltic horizons within the cores, we detail an improved method for cross-core correlation based on stratigraphy and geochemical fingerprinting. We present major and trace element data for individual glass shards from 57 separate basaltic horizons identified within the cores. Our results suggest that in cases where major element compositions (SiO2, CaO, Al2O3, FeO, MgO) do not provide unambiguous correlations, trace elements (e.g. La, Gd, Yb, Zr, Nb, Nd) and trace element ratios (e.g. [La/Yb]N, [Gd/Yb]N, [Zr/Yb]N) are successful in improving the compositional distinction between the AVF basaltic tephra horizons, thereby allowing an improved eruptive history of the AVF to be reconstructed.

  16. Health, sexuality and place: the different geographies of HIV-positive gay men in Auckland, New Zealand.

    PubMed

    Myers, Jason

    2010-01-01

    This paper employs interview narratives alongside participant-led photography and caption writing to examine the different daily geographies of 15 HIV-positive gay men in Auckland, New Zealand. Difference for these men is rooted in both their HIV status and their sexuality, and this difference has implications for their engagement with the world at a range of spatial and temporal scales. Giving voice to such experiences begins to answer calls for geographers to consider more deeply the connections between health, sexuality and place.

  17. Characterisation of urban catchment suspended particulate matter (Auckland region, New Zealand); a comparison with non-urban SPM.

    PubMed

    Bibby, Rebecca L; Webster-Brown, Jenny G

    2005-05-01

    Suspended particulate matter (SPM) is an important transport agent for metal contaminants in streams, particularly during high flow periods such as storm events. For highly contaminated urban catchments in the greater Auckland (New Zealand) area, trace metal partitioning between the dissolved phase and SPM was determined, and SPM characterised in terms of its Si, Al, Fe, Mn, Zn, Cu, Pb, TOC, TON and PO(4) concentrations, as well as particle size, abundance, type and surface area. This data was compared to similar data from representative non-urban catchments in the Auckland region, the Kaipara River and Waikato River catchments, to identify any significant differences in the SPM and its potential trace metal adsorption capacity. Trace metal partitioning was assessed by way of a distribution coefficient: K(D)=[Me(SPM)]/[Me(DISS)]. Auckland urban SPM comprises quartz, feldspars and clay minerals, with Fe-oxides and minor Mn-oxides. No particles of anthropogenic origin, other than glass shards, were observed. No change in urban SPM particle size or SSA was observed with seasonal change in temperature, but the nature of the SPM was observed to change with flow regime. The abundance of finer particles, SSA and Al content of the SPM increased under moderate flow conditions; however, Si/Al ratios remained constant, confirming the importance of aluminosilicate detrital minerals in surface run-off. The SPM Fe content was observed to decrease with increased flow and was attributed to dilution of SPM Fe-oxide of groundwater origin. The Kaipara River SPM was found to be mineralogically, chemically and biologically similar to the urban SPM. However, major differences between urban catchment SPM and SPM from the much larger (non-urban) Waikato River were observed, and attributed to a higher abundance of diatoms. The Fe content of the Waikato River SPM was consistently lower (<5%), and the Si/Al ratio and Mn content was higher. Such differences observed between urban and non

  18. Incidence of Transient Ischemic Attack in Auckland, New Zealand, in 2011 to 2012.

    PubMed

    Barber, P Alan; Krishnamurthi, Rita; Parag, Varsha; Anderson, Neil E; Ranta, Annemarei; Kilfoyle, Dean; Wong, Edward; Green, Geoff; Arroll, Bruce; Bennett, Derrick A; Witt, Emma; Rush, Elaine; Minsun Suh, Flora; Theadom, Alice; Rathnasabapathy, Yogini; Te Ao, Braden; Parmar, Priyakumari; Feigin, Valery L

    2016-09-01

    There have been few recent population-based studies reporting the incidence (first ever) and attack rates (incident and recurrent) of transient ischemic attack (TIA). The fourth Auckland Regional Community Stroke study (ARCOS IV) used multiple overlapping case ascertainment methods to identify all hospitalized and nonhospitalized cases of TIA that occurred in people ≥16 years of age usually resident in Auckland (population ≥16 years of age is 1.12 million), during the 12 months from March 1, 2011. All first-ever and recurrent new TIAs (any new TIA 28 days after the index event) during the study period were recorded. There were 785 people with TIA (402 [51.2%] women, mean [SD] age 71.5 [13.8] years); 614 (78%) of European origin, 84 (11%) Māori/Pacific, and 75 (10%) Asian/Other. The annual incidence of TIA was 40 (95% confidence interval, 36-43), and attack rate was 63 (95% confidence interval, 59-68), per 100 000 people, age standardized to the World Health Organization world population. Approximately two thirds of people were known to be hypertensive or were being treated with blood pressure-lowering agents, half were taking antiplatelet agents and just under half were taking lipid-lowering therapy before the index TIA. Two hundred ten (27%) people were known to have atrial fibrillation at the time of the TIA, of whom only 61 (29%) were taking anticoagulant therapy, suggesting a failure to identify or treat atrial fibrillation. This study describes the burden of TIA in an era of aggressive primary and secondary vascular risk factor management. Education programs for medical practitioners and patients around the identification and management of atrial fibrillation are required. © 2016 American Heart Association, Inc.

  19. Evidence of Lake Trout reproduction at Lake Michigan's mid-lake reef complex

    USGS Publications Warehouse

    Janssen, J.; Jude, D.J.; Edsall, T.A.; Paddock, R.W.; Wattrus, N.; Toneys, M.; McKee, P.

    2006-01-01

    The Mid-Lake Reef Complex (MLRC), a large area of deep (> 40 m) reefs, was a major site where indigenous lake trout (Salvelinus namaycush) in Lake Michigan aggregated during spawning. As part of an effort to restore Lake Michigan's lake trout, which were extirpated in the 1950s, yearling lake trout have been released over the MLRC since the mid-1980s and fall gill net censuses began to show large numbers of lake trout in spawning condition beginning about 1999. We report the first evidence of viable egg deposition and successful lake trout fry production at these deep reefs. Because the area's existing bathymetry and habitat were too poorly known for a priori selection of sampling sites, we used hydroacoustics to locate concentrations of large fish in the fall; fish were congregating around slopes and ridges. Subsequent observations via unmanned submersible confirmed the large fish to be lake trout. Our technological objectives were driven by biological objectives of locating where lake trout spawn, where lake trout fry were produced, and what fishes ate lake trout eggs and fry. The unmanned submersibles were equipped with a suction sampler and electroshocker to sample eggs deposited on the reef, draw out and occasionally catch emergent fry, and collect egg predators (slimy sculpin Cottus cognatus). We observed slimy sculpin to eat unusually high numbers of lake trout eggs. Our qualitative approaches are a first step toward quantitative assessments of the importance of lake trout spawning on the MLRC.

  20. Five-year follow-up of an acute psychiatric admission cohort in Auckland, New Zealand.

    PubMed

    Wheeler, Amanda; Moyle, Stuart; Jansen, Carol; Robinson, Elizabeth; Vanderpyl, Jane

    2011-06-10

    This paper describes a follow-up of acute psychiatric hospital contact in Auckland, New Zealand for an admission cohort in the 5-years past an index admission (published in the NZMJ in 2005). A 5-year follow-up study of hospital psychiatric service utilisation by 924 patients admitted (index admission) in Auckland during 2000. Hospital admissions within New Zealand for this population were extracted from electronic records. Relevant demographic information (gender, age and ethnicity) and clinical data (primary diagnosis at index admission and admission history) were included for each person. Descriptive analysis of inpatient data and negative binomial regression models were conducted. Of 924 patients, 38.5% had no readmissions anywhere in New Zealand in the 5-years following index discharge. 41.0% were readmitted within 12 months and 61.4% were readmitted within 5 years of index discharge. Only 5.6% experienced an admission every year for the 5-years post index admission. Readmission was least likely for those with index discharge diagnosis of depression. A history of admissions prior to index admission and Maori ethnicity were characteristics associated with higher numbers of readmission. Those who were younger, or a diagnosis of schizophrenia/schizoaffective disorder or previous admissions tended to have longer total length of stay over the 5-years. More than a third of patients had no further hospital contact and the two factors associated with readmission were a history of previous admissions and Maori ethnicity. Reliable community-based data needs to be a priority to enable exploration of community service utilisation and impact of service alternatives to hospital for acute care.

  1. 77 FR 41686 - Safety Zone; Sheffield Lake Fireworks, Lake Erie, Sheffield Lake, OH

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-16

    ...-AA00 Safety Zone; Sheffield Lake Fireworks, Lake Erie, Sheffield Lake, OH AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on Lake Erie, Sheffield Lake, OH. This safety zone is intended to restrict vessels from a portion of Lake Erie...

  2. Barriers to early initiation of antenatal care in a multi-ethnic sample in South Auckland, New Zealand.

    PubMed

    Corbett, Sarah; Chelimo, Carol; Okesene-Gafa, Kara

    2014-10-17

    To identify barriers to early initiation of antenatal care amongst pregnant women in South Auckland, New Zealand. Women in late pregnancy (>37 weeks gestation) or who had recently delivered (<6 weeks postnatal) completed a questionnaire about their antenatal care. Logistic regression analysis evaluated whether late booking for antenatal care was associated with demographic factors and potential barriers to accessing care. Of the 826 women who participated, 137 (17%) booked for antenatal care at >18 weeks (late bookers). The ethnic composition of the sample was: 43% Pacific Peoples, 20% Maori, 14% Asian, and 21% European or other ethnicities. The multivariate analysis indicated that women were significantly more likely to book late for antenatal care if they had limited resources (OR=1.86; 95% CI=1.17-2.93), no tertiary education (OR=1.96; 95% CI=1.23-3.15), or were not living with a husband/partner (OR=2.34; 95% CI=1.48-3.71). In addition, the odds of late booking for antenatal care was almost six times higher among Maori (OR=5.70; 95% CI=2.57-12.64) and Pacific (OR=5.90; 95% CI=2.83-12.29) women compared to those of European and other ethnicities. Late booking for antenatal care in the Counties Manukau District Health Board area (South Auckland) is associated with sociodemographic factors, social deprivation, and inadequate social support.

  3. Low sugar nutrition policies and dental caries: A study of primary schools in South Auckland.

    PubMed

    Thornley, Simon; Marshall, Roger; Reynolds, Gary; Koopu, Pauline; Sundborn, Gerhard; Schofield, Grant

    2017-05-01

    The study assessed whether a healthy food policy implemented in one school, Yendarra Primary, situated in a socio-economically deprived area of South Auckland, had improved student oral health by comparing dental caries levels with students of similar schools in the same region with no such policy. Records of caries of the primary and adult teeth were obtained between 2007 and 2014 for children attending Yendarra, and were compared to those of eight other public schools in the area, with a similar demographic profile. Children were selected between the ages of 8 and 11 years. Linear regression models were used to estimate the strength of association between attending Yendarra school and dental caries. During the study period, 3813 records were obtained of children who attended dental examinations and the schools of interest. In a linear model, mean number of carious primary and adult teeth were 0.37 lower (95% confidence interval: 0.09-0.65) in Yendarra school children, compared to those in other schools, after adjustment for confounders. Pacific students had higher numbers of carious teeth (adjusted β coefficient: 0.25; 95% confidence interval: 0.03-0.46) than Māori. This nutrition policy, implemented in a school in the poorest region of South Auckland, which restricted sugary food and drink availability, was associated with a marked positive effect on the oral health of students, compared to students in surrounding schools. We recommend that such policies are a useful means of improving child oral health. © 2017 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  4. Lake trout rehabilitation in Lake Ontario

    USGS Publications Warehouse

    Elrod, Joseph H.; O'Gorman, Robert; Schneider, Clifford P.; Eckert, Thomas H.; Schaner, Ted; Bowlby, James N.; Schleen, Larry P.

    1995-01-01

    Attempts to maintain the native lake trout (Salvelinus namaycush) population in Lake Ontario by stocking fry failed and the species was extirpated by the 1950s. Hatchery fish stocked in the 1960s did not live to maturity because of sea lamprey (Petromyzon marinus) predation and incidental commercial harvest. Suppression of sea lampreys began with larvicide treatments of Lake Ontario tributaries in 1971 and was enhanced when the tributaries of Oneida Lake and Lake Erie were treated in the 1980s. Annual stocking of hatchery fish was resumed with the 1972 year class and peaked at about 1.8 million yearlings and 0.3 million fingerlings from the 1985–1990 year classes. Survival of stocked yearlings declined over 50% in the 1980 s and was negatively correlated with the abundance of lake trout > 550 mm long (r = −0.91, P < 0.01, n = 12). A slot length limit imposed by the State of New York for the 1988 fishing season reduced angler harvest. Angler harvest in Canadian waters was 3 times higher in eastern Lake Ontario than in western Lake Ontario. For the 1977–1984 year classes, mean annual survival rate of lake trout age 6 and older was 0.45 (range: 0.35–0.56). In U.S. waters during 1985–1992, the total number of lake trout harvested by anglers was about 2.4 times greater than that killed by sea lampreys. The number of unmarked lake trout < 250 mm long in trawl catches in 1978–1992 was not different from that expected due to loss of marks and failure to apply marks at the hatchery, and suggested that recruitment of naturally-produced fish was nil. However, many of the obstacles which may have impeded lake trout rehabilitation in Lake Ontario during the 1980s are slowly being removed, and there are signs of a general ecosystem recovery. Significant recruitment of naturally produced lake trout by the year 2000, one interim objective of the rehabilitation plan for the Lake, may be achieved.

  5. Lake level variability in Silver Lake, Michigan: a response to fluctuations in lake levels of Lake Michigan

    USGS Publications Warehouse

    Fisher, Timothy G.; Loope, Walter L.

    2004-01-01

    Sediment from Silver Lake, Michigan, can be used to constrain the timing and elevation of Lake Michigan during the Nipissing transgression. Silver Lake is separated from Lake Michigan by a barrier/dune complex and the Nipissing, Calumet, and Glenwood shorelines of Lake Michigan are expressed landward of this barrier. Two Vibracores were taken from the lake in February 2000 and contain pebbly sand, sand, buried soils, marl, peat, and sandy muck. It is suggested here that fluctuations in the level of Lake Michigan are reflected in Silver Lake since the Chippewa low phase, and possibly at the end of the Algonquin phase. An age of 12,490 B.P. (10,460±50 14C yrs B.P.) on wood from a buried Entisol may record the falling Algonquin phase as the North Bay outlet opened. A local perched water table is indicated by marl deposited before 7,800 B.P. and peat between 7,760-7,000 B.P. when Lake Michigan was at the low elevation Chippewa phase. Continued deepening of the lake is recorded by the transition from peat to sandy muck at 7,000 B.P. in the deeper core, and with the drowning of an Inceptisol nearly 3 m higher at 6,410 B.P. in the shallower core. A rising groundwater table responding to a rising Lake Michigan base level during the Nipissing transgression, rather than a response to mid-Holocene climate change, explains deepening of Silver Lake. Sandy muck was deposited continually in Silver Lake between Nipissing and modern time. Sand lenses within the muck are presumed to be eolian in origin, derived from sand dunes advancing into the lake on the western side of the basin.

  6. Dynamics of the earth magnetic field in the 10-75 kyr period comprising the Laschamp and Mono Lake excursions: New results from the French Chaîne des Puys in a global perspective

    NASA Astrophysics Data System (ADS)

    Laj, Carlo; Guillou, Hervé; Kissel, Catherine

    2014-02-01

    We report here on a new paleomagnetic (directions and intensities) and coupled K/Ar and 40Ar/39Ar analysis of 35 different flows, emplaced in the Chaîne des Puys during the 75 to 10 kyr interval, which contains the Mono Lake and Laschamp excursions. There is a remarkable agreement between the new set of absolute volcanic intensities and published sedimentary (GLOPIS-75) and cosmogenic (10Be and 36Cl) records. The Laschamp and Mono Lake excursions are clearly revealed by a very significant intensity drop at 41.2±1.6 ka and 34.2±1.2 ka respectively. The duration of the Laschamp excursion is ˜1500 yr and about 640 yr when the drop of paleointensity or the directional change are considered respectively. The intensity drop at the Mono Lake is twice as short. In the ˜7 ka interval separating the two excursions, the field intensity recovers to almost non-transitional values. The rate of decrease of the field intensity during these excursions attains 18 nT/yr for the Laschamp and even greater value (33 nT/yr) for the Mono Lake. This figure is, for the Laschamp excursion, similar to the present field intensity decrease in the last two centuries so that one may wonder whether such a high rate of change may be characteristic of an impending geomagnetic event (reversal or excursion). We suggest that the name Auckland excursion should be used for the present-day called Mono Lake.

  7. Microplastic pollution in lakes and lake shoreline sediments - A case study on Lake Bolsena and Lake Chiusi (central Italy).

    PubMed

    Fischer, Elke Kerstin; Paglialonga, Lisa; Czech, Elisa; Tamminga, Matthias

    2016-06-01

    Rivers and effluents have been identified as major pathways for microplastics of terrestrial sources. Moreover, lakes of different dimensions and even in remote locations contain microplastics in striking abundances. This study investigates concentrations of microplastic particles at two lakes in central Italy (Lake Bolsena, Lake Chiusi). A total number of six Manta Trawls have been carried out, two of them one day after heavy winds occurred on Lake Bolsena showing effects on particle distribution of fragments and fibers of varying size categories. Additionally, 36 sediment samples from lakeshores were analyzed for microplastic content. In the surface waters 2.68 to 3.36 particles/m(3) (Lake Chiusi) and 0.82 to 4.42 particles/m(3) (Lake Bolsena) were detected, respectively. Main differences between the lakes are attributed to lake characteristics such as surface and catchment area, depth and the presence of local wind patterns and tide range at Lake Bolsena. An event of heavy winds and moderate rainfall prior to one sampling led to an increase of concentrations at Lake Bolsena which is most probable related to lateral land-based and sewage effluent inputs. The abundances of microplastic particles in sediments vary from mean values of 112 (Lake Bolsena) to 234 particles/kg dry weight (Lake Chiusi). Lake Chiusi results reveal elevated fiber concentrations compared to those of Lake Bolsena what might be a result of higher organic content and a shift in grain size distribution towards the silt and clay fraction at the shallow and highly eutrophic Lake Chiusi. The distribution of particles along different beach levels revealed no significant differences. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Lake whitefish and lake herring population structure and niche in ten south-central Ontario lakes

    USGS Publications Warehouse

    Carl, Leon M.; McGuiness, Fiona

    2006-01-01

    This study compares simple fish communities of ten oligotrophic lakes in south-central Ontario. Species densities and population size structure vary significantly among these lake communities depending on fish species present beyond the littoral zone. Lake whitefish are fewer and larger in the presence of lake herring than in their absence. Diet analysis indicates that lake whitefish shift from feeding on both plankton and benthic prey when lake herring are absent to a primarily benthic feeding niche in the presence of lake herring. When benthic round whitefish are present, lake whitefish size and density decline and they move lower in the lake compared to round whitefish. Burbot are also fewer and larger in lakes with lake herring than in lakes without herring. Burbot, in turn, appear to influence the population structure of benthic coregonine species. Lower densities of benthic lake whitefish and round whitefish are found in lakes containing large benthic burbot than in lakes with either small burbot or where burbot are absent. Predation on the pelagic larvae of burbot and lake whitefish by planktivorous lake herring alters the size and age structure of these populations. As life history theory predicts, those species with poor larval survival appear to adopt a bet-hedging life history strategy of long-lived individuals as a reproductive reserve.

  9. Increased uptake of cervical screening by women with HIV infection in Auckland regardless of ethnicity, requirement for an interpreter or level of education.

    PubMed

    Lowe, Michele; Handy, Rupert; Ingram, Joan; Nisbet, Mitzi; Ritchie, Stephen; Thomas, Mark; Briggs, Simon

    2016-07-15

    Current guidelines recommend that women with HIV infection receive annual cervical smears. We evaluated the uptake of annual cervical smears by women with HIV infection under the care of the Infectious Disease Service at Auckland City Hospital. In an attempt to identify potential barriers to regularly receiving an annual cervical smear, we invited the women to complete a questionnaire. The responses from women who had regularly received an annual cervical smear were compared with those who had not. The proportion of women who had received a cervical smear increased from 44% in 2001, to 73% in 2010 (p=0.001). Ninety-three women (76%) completed the study questionnaire. No statistically significant differences were found in the questionnaire responses between the women who had regularly received an annual cervical smear and those who had not. The proportion of women in this cohort who received a cervical smear in 2010 is comparable with other studies of women with HIV infection in New Zealand and overseas. We have not been able to identify barriers that prevent women with HIV infection in Auckland regularly receiving an annual cervical smear. We plan to encourage women who have not received a cervical smear in the previous 2-year period to have a cervical smear performed when they attend the Infectious Disease Clinic, and will continue to notify the National Cervical Screening Programme that all women who are newly diagnosed with HIV infection should have an annual recall code attached to future cervical smear reports. We expect that these interventions will further increase the proportion of women with HIV infection in Auckland who receive an annual cervical smear.

  10. Analysis of the Auckland 2014 measles outbreak indicates that adolescents and young adults could benefit from catch-up vaccination.

    PubMed

    Reynolds, Gary; Dias, Cassandra; Thornley, Simon; King, Ronald; Morrison, Anne; Matson, Angela; Hoskins, Richard

    2015-09-25

    To analyse the epidemiology, serology and vaccine effectiveness in a recent New Zealand measles outbreak that started in Auckland, from December, 2013 to June, 2014, to guide further preventive measures. Cases had a clinically compatible illness, which was either confirmed by PCR or serology, or were linked to a laboratory confirmed case. A total of 113 cases with 3,113 contacts were traced and managed in the Auckland region. Thirteen overseas acquired cases, produced a total of 98 locally acquired secondary cases, (plus two cases with unknown travel history). The majority of cases occurred in adolescents and young adults; 68/113 cases (60.1%) were aged 10 to 19 years. Among cases, 38.9% (44/113) were unimmunised, and 31.8% (36/113) had unknown immunisation status. A further 15.0% (17/113) of cases had received one or two doses of measles, mumps, rubella (MMR) vaccine. Of the contacts who underwent serological testing for immunity (n=735), the lowest levels of serological immunity were observed in people aged 10 to 24 years. Vaccine effectiveness was calculated for the 15-24 year age cohort at 92% (95%CI; 82-97). Results suggest that an adolescent catch-up immunisation programme would prevent further outbreaks of imported measles.

  11. Treatment of gonorrhoea in Auckland, New Zealand: marked variation in prescriber adherence to treatment guidelines.

    PubMed

    Forster, Rose; Ng, Diana; Upton, Arlo; Franklin, Rick; Thomas, Mark

    2017-06-01

    The relentless emergence and spread of strains of Neisseria gonorrhoeae that are resistant to many antimicrobial agents has led to frequent changes in treatment guidelines, with a consequent risk that prescribers may not be aware of current guidelines. To determine the proportion of patients with gonorrhoea who were treated with a regimen consistent with the New Zealand Sexual Health Society (NZSHS) guidelines. We audited the treatment given to adult patients with laboratory-proven gonorrhoea in Auckland, New Zealand, during the first 6 months of 2015. Treatment compliant with the current NZSHS guidelines was administered in only 65% (458/706) episodes overall. Guideline-compliant treatment was much more likely to be prescribed for patients who presented to a sexual health clinic (89%) than for patients who presented to either a general practice or other community clinic (52%) or to a hospital (56%) (P < 0.0001). Overall, 52 of 706 (7%) episodes were not treated with any antimicrobial regimen by the service that diagnosed the patients' gonorrhoea, 13 of 62 (21%) episodes in patients who presented to a hospital, 34 of 403 (8%) episodes in patients who presented to a general practice or other community clinic and 5 of 241 (2%) episodes in patients who presented to a sexual health clinic (P < 0.0001). Low levels of compliance with treatment guidelines increase the risk that antibiotic-resistant strains of N. gonorrhoeae will spread within the Auckland region. Improved compliance with treatment guidelines, particularly in patients who present either to general practice or to hospitals, is necessary to maintain the efficacy of current treatment regimens. © 2017 Royal Australasian College of Physicians.

  12. Vitamin D status and attitudes towards sun exposure in South Asian women living in Auckland, New Zealand.

    PubMed

    von Hurst, Pamela R; Stonehouse, Welma; Coad, Jane

    2010-04-01

    To determine the vitamin D status of women of South Asian origin living in Auckland, New Zealand, and to investigate their attitudes and behaviours with regard to sun exposure. Cross-sectional study. Auckland, New Zealand. Women of South Asian origin (n 235) aged 20 years and older were tested for serum 25(OH)D, and 228 were included in these analyses. Of these, 140 completed a questionnaire about attitudes and behaviours to sun exposure, and health motivation. Exclusion criteria included high dose (>1000 IU/d) supplementation with 25(OH)D3, or any supplementation with 1,25(OH)2D3. As serum vitamin D concentrations were not normally distributed, data are reported as median (25th, 75th percentile). Median serum 25(OH)D3 was 27.5 (18.0, 41.0) nmol/l. Adequate concentrations (>50 nmol/l) were observed in only 16 % of the subjects. Concern about skin cancer and the strength of the New Zealand sun were the most prevalent reasons given for sun avoidance, with 65 % saying they did avoid the sun. However, a seasonal variation was observed, with concentrations reducing significantly (P < 0.001) from summer through to early spring by 19.5 nmol/l. The results of the present study suggest that South Asian women are at high risk of hypovitaminosis D, due, in part, to deliberate sun avoidance and an indoor lifestyle, and that they are especially vulnerable in winter and spring.

  13. Construction of the North Head (Maungauika) tuff cone: a product of Surtseyan volcanism, rare in the Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Agustín-Flores, Javier; Németh, Károly; Cronin, Shane J.; Lindsay, Jan M.; Kereszturi, Gábor

    2015-02-01

    The Auckland Volcanic Field (AVF) comprises at least 52 monogenetic eruption centres dispersed over ˜360 km2. Eruptions have occurred sporadically since 250 ka, predominantly when glacio-eustatic sea levels were lower than today. Now that around 35 % of the field is covered by shallow water (up to 30 m depth), any eruption occurring in the present or near future within this area may display Surtseyan dynamics. The North Head tuff cone evidences eruptive dynamics caused by magma interaction with seawater. The first stages of the eruption comprise a phreatomagmatic phase that built a 48-m-high tuff cone. North Head tuff deposits contain few lithic fragments (<10 vol%) and are characterized by deposits from collapsing tephra jets and fall from relatively wet tephra columns. The conditions needed for this eruption existed between 128 and 116 ka, when the sea level in the Auckland area was at least 10-12 m above the pre-eruptive surface. The hazards associated with this type of eruption pose a risk to the densely populated coastal residential zones and the activities of one of the busiest harbours in New Zealand.

  14. The spatial and temporal `cost' of volcanic eruptions: assessing economic impact, business inoperability, and spatial distribution of risk in the Auckland region, New Zealand

    NASA Astrophysics Data System (ADS)

    McDonald, Garry W.; Smith, Nicola J.; Kim, Joon-hwan; Cronin, Shane J.; Proctor, Jon N.

    2017-07-01

    Volcanic risk assessment has historically concentrated on quantifying the frequency, magnitude, and potential diversity of physical processes of eruptions and their consequent impacts on life and property. A realistic socio-economic assessment of volcanic impact must however take into account dynamic properties of businesses and extend beyond only measuring direct infrastructure/property loss. The inoperability input-output model, heralded as one of the 10 most important accomplishments in risk analysis over the last 30 years (Kujawaski Syst Eng. 9:281-295, 2006), has become prominent over the last decade in the economic impact assessment of business disruptions. We develop a dynamic inoperability input-output model to assess the economic impacts of a hypothetical volcanic event occurring at each of 7270 unique spatial locations throughout the Auckland Volcanic Field, New Zealand. This field of at least 53 volcanoes underlies the country's largest urban area, the Auckland region, which is home to 1.4 million people and responsible for 35.3% (NZ201481.2 billion) of the nation's GDP (Statistics New Zealand 2015). We apply volcanic event characteristics for a small-medium-scale volcanic eruption scenario and assess the economic impacts of an `average' eruption in the Auckland region. Economic losses are quantified both with, and without, business mitigation and intervention responses in place. We combine this information with a recent spatial hazard probability map (Bebbington and Cronin Bull Volcanol. 73(1):55-72, 2011) to produce novel spatial economic activity `at risk' maps. Our approach demonstrates how business inoperability losses sit alongside potential life and property damage assessment in enhancing our understanding of volcanic risk mitigation.

  15. Presentations by youth to Auckland emergency departments following a suicide attempt.

    PubMed

    Bennett, Sara; Coggan, Carolyn; Hooper, Rhonda; Lovell, Cherie; Adams, Peter

    2002-09-01

    The objective of this study was to describe the population of European youth (15-24 years) presenting to emergency departments (EDs) at one of the three Auckland public hospitals following attempted suicide; and to identify factors associated with presentations to EDs by these youth. A 1-year medical record review was undertaken. A total of 212 presentations (196 individuals) occurred during the surveillance; alcohol was present for 29%. Attempts involving alcohol were more likely to occur at weekends (P < 0.01); involve cutting and piercing (P < 0.05); be undertaken by employed people (P < 0.05), and be undertaken by those not residing with family (P < 0.01). Two groups of particular concern were identified: those who involved alcohol in their attempt; and those who represented during the study period following multiple suicide attempts. These findings have implications for immediate care within an ED setting, and long-term follow-up healthcare options for distressed young people.

  16. Phreatomagmatic eruptions through unconsolidated coastal plain sequences, Maungataketake, Auckland Volcanic Field (New Zealand)

    NASA Astrophysics Data System (ADS)

    Agustín-Flores, Javier; Németh, Károly; Cronin, Shane J.; Lindsay, Jan M.; Kereszturi, Gábor; Brand, Brittany D.; Smith, Ian E. M.

    2014-04-01

    Maungataketake is a monogenetic basaltic volcano formed at ~ 85-89 ka in the southern part of the Auckland Volcanic Field (AVF), New Zealand. It comprises a basal 1100-m diameter tuff ring, with a central scoria/spatter cone and lava flows. The tuff ring was formed under hydrogeological and geographic conditions very similar to the present. The tuff records numerous density stratified, wet base surges that radiated outward up to 1 km, decelerating rapidly and becoming less turbulent with distance. The pyroclastic units dominantly comprise fine-grained expelled grains from various sedimentary deposits beneath the volcano mixed with a minor component of juvenile pyroclasts (~ 35 vol.%). Subtle lateral changes relate to deceleration with distance and vertical transformations are minor, pointing to stable explosion depths and conditions, with gradual transitions between units and no evidence for eruptive pauses. This volcano formed within and on ~ 60 m-thick Plio/Pleistocene, poorly consolidated, highly permeable shelly sands and silts (Kaawa Formation) capped by near-impermeable, water-saturated muds (Tauranga Group). These sediments rest on moderately consolidated Miocene-aged permeable turbiditic sandstones and siltstones (Waitemata Group). Magma-water fuelled thermohydraulic explosions remained in the shallow sedimentary layers, excavating fine-grained sediments without brittle fragmentation required. On the whole, the resulting cool, wet pyroclastic density currents were of low energy. The unconsolidated shallow sediments deformed to accommodate rapidly rising magma, leading to development of complex sill-like bodies and a range of magma-water contact conditions at any time. The weak saturated sediments were also readily liquefied to provide an enduring supply of water and fine sediment to the explosion loci. Changes in magma flux and/or subsequent stabilisation of the conduit area by a lava ring-barrier led to ensuing Strombolian and fire-fountaining eruption

  17. 2016 Lake Michigan Lake Trout Working Group Report

    USGS Publications Warehouse

    Madenjian, Charles P.; Breidert, Brian; Boyarski, David; Bronte, Charles R.; Dickinson, Ben; Donner, Kevin; Ebener, Mark P.; Gordon, Roger; Hanson, Dale; Holey, Mark; Janssen, John; Jonas, Jory; Kornis, Matthew; Olsen, Erik; Robillard, Steve; Treska, Ted; Weldon, Barry; Wright, Greg D.

    2017-01-01

    This report provides a review on the progression of lake trout rehabilitation towards meeting the Salmonine Fish Community Objectives (FCOs) for Lake Michigan (Eshenroder et. al. 1995) and the interim goal and evaluation objectives articulated in A Fisheries Management Implementation Strategy for the Rehabilitation of Lake Trout in Lake Michigan (Dexter et al. 2011); we also include data describing lake trout stocking and mortality to portray the present state of progress towards lake trout rehabilitation.

  18. Contaminants in American alligator eggs from Lake Apopka, Lake Griffin, and Lake Okeechobee, Florida

    USGS Publications Warehouse

    Heinz, Gary H.; Percival, H. Franklin; Jennings, Michael L.

    1991-01-01

    Residues of organochlorine pesticides, polychlorinated biphenyls (PCBs), and 16 elements were measured in American alligator (Alligator mississippiensis) eggs collected in 1984 from Lakes Apopka, Griffin, and Okeechobee in central and south Florida. Organochlorine pesticides were highest in eggs from Lake Apopka. None of the elements appeared to be present at harmful concentrations in eggs from any of the lakes. A larger sample of eggs was collected in 1985, but only from Lakes Griffin, a lake where eggs were relatively clean, and Apopka, where eggs were most contaminated. In 1985, hatching success of artificially incubated eggs was lower for Lake Apopka, and several organochlorine pesticides were higher than in eggs from Lake Griffin. However, within Lake Apopka, higher levels of pesticides in chemically analyzed eggs were not associated with reduced hatching success of the remaining eggs in the clutch. Therefore, it did not appear that any of the pesticides we measured were responsible for the reduced hatching success of Lake Apopka eggs.

  19. A Probabilistic Tsunami Hazard Study of the Auckland Region, Part I: Propagation Modelling and Tsunami Hazard Assessment at the Shoreline

    NASA Astrophysics Data System (ADS)

    Power, William; Wang, Xiaoming; Lane, Emily; Gillibrand, Philip

    2013-09-01

    Regional source tsunamis represent a potentially devastating threat to coastal communities in New Zealand, yet are infrequent events for which little historical information is available. It is therefore essential to develop robust methods for quantitatively estimating the hazards posed, so that effective mitigation measures can be implemented. We develop a probabilistic model for the tsunami hazard posed to the Auckland region of New Zealand from the Kermadec Trench and the southern New Hebrides Trench subduction zones. An innovative feature of our model is the systematic analysis of uncertainty regarding the magnitude-frequency distribution of earthquakes in the source regions. The methodology is first used to estimate the tsunami hazard at the coastline, and then used to produce a set of scenarios that can be applied to produce probabilistic maps of tsunami inundation for the study region; the production of these maps is described in part II. We find that the 2,500 year return period regional source tsunami hazard for the densely populated east coast of Auckland is dominated by events originating in the Kermadec Trench, while the equivalent hazard to the sparsely populated west coast is approximately equally due to events on the Kermadec Trench and the southern New Hebrides Trench.

  20. Automated statistical matching of multiple tephra records exemplified using five long maar sequences younger than 75 ka, Auckland, New Zealand

    NASA Astrophysics Data System (ADS)

    Green, Rebecca M.; Bebbington, Mark S.; Cronin, Shane J.; Jones, Geoff

    2014-09-01

    Detailed tephrochronologies are built to underpin probabilistic volcanic hazard forecasting, and to understand the dynamics and history of diverse geomorphic, climatic, soil-forming and environmental processes. Complicating factors include highly variable tephra distribution over time; difficulty in correlating tephras from site to site based on physical and chemical properties; and uncertain age determinations. Multiple sites permit construction of more accurate composite tephra records, but correctly merging individual site records by recognizing common events and site-specific gaps is complex. We present an automated procedure for matching tephra sequences between multiple deposition sites using stochastic local optimization techniques. If individual tephra age determinations are not significantly different between sites, they are matched and a more precise age is assigned. Known stratigraphy and mineralogical or geochemical compositions are used to constrain tephra matches. We apply this method to match tephra records from five long sediment cores (≤ 75 cal ka BP) in Auckland, New Zealand. Sediments at these sites preserve basaltic tephras from local eruptions of the Auckland Volcanic Field as well as distal rhyolitic and andesitic tephras from Okataina, Taupo, Egmont, Tongariro, and Tuhua (Mayor Island) volcanic centers. The new correlated record compiled is statistically more likely than previously published arrangements from this area.

  1. Sanctuaries for lake trout in the Great Lakes

    USGS Publications Warehouse

    Stanley, Jon G.; Eshenroder, Randy L.; Hartman, Wilbur L.

    1987-01-01

    Populations of lake trout, severely depleted in Lake Superior and virtually extirpated from the other Great Lakes because of sea lamprey predation and intense fishing, are now maintained by annual plantings of hatchery-reared fish in Lakes Michigan, Huron, and Ontario and parts of Lake Superior. The extensive coastal areas of the Great Lakes and proximity to large populations resulted in fishing pressure on planted lake trout heavy enough to push annual mortality associated with sport and commercial fisheries well above the critical level needed to reestablish self-sustaining stocks. The interagency, international program for rehabilitating lake trout includes controlling sea lamprey abundance, stocking hatchery-reared lake trout, managing the catch, and establishing sanctuaries where harvest is prohibited. Three lake trout sanctuaries have been established in Lake Michigan: the Fox Island Sanctuary of 121, 500 ha, in the Chippewa-Ottawa Treaty fishing zone in the northern region of the lake; the Milwaukee Reef Sanctuary of 160, 000 ha in midlake, in boundary waters of Michigan and Wisconsin; and Julian's Reef Sanctuary of 6, 500 ha, in Illinois waters. In northern Lake Huron, Drummond Island Sanctuary of 55, 000 ha is two thirds in Indian treaty-ceded waters in Michigan and one third in Ontario waters of Canada. A second sanctuary, Six Fathom Bank-Yankee Reef Sanctuary, in central Lake Huron contains 168, 000 ha. Sanctuary status for the Canadian areas remains to be approved by the Provincial government. In Lake Superior, sanctuaries protect the spawning grounds of Gull Island Shoal (70, 000 ha) and Devils Island Shoal (44, 000 ha) in Wisconsin's Apostle Island area. These seven sanctuaries, established by the several States and agreed upon by the States, Indian tribes, the U.S. Department of the Interior, and the Province of Ontario, contribute toward solving an interjurisdictional fishery problem.

  2. Water quality of Lake Austin and Town Lake, Austin, Texas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Andrews, F.L.; Wells, F.C.; Shelby, W.J.

    1988-01-01

    Lake Austin and Town Lake are impoundments on the Colorado River in Travis County, central Texas, and are a source of water for municipal industrial water supplies, electrical-power generation, and recreation for more than 500,000 people in the Austin metropolitan area. Small vertical temperature variations in both lakes were attributed to shallow depths in the lakes and short retention times of water in the lakes during the summer months. The largest areal variations in dissolved oxygen generally occur in Lake Austin during the summer as a result of releases of water from below the thermocline in Lake Travis. Except formore » iron, manganese, and mercury, dissolved concentrations of trace elements in water collected from Lake Austin and Town Lake did not exceed the primary or secondary drinking water standards set by the US Environmental Protection Agency. Little or no effect of stormwater runoff on temperature, dissolved oxygen, or minor elements could be detected in either Lake Austin or Town Lake. Little seasonal or areal variation was noted in nitrogen concentrations in Lake Austin or Town lake. Total phosphorus concentrations generally were small in both lakes. Increased concentrations of nitrogen and phosphorus were detected after storm runoff inflow in Town Lake, but not in Lake Austin; densities of fecal-coliform bacteria increased in Lake Austin and Town Lake, but were substantially greater in Town Lake than in Lake Austin. 18 refs., 38 figs., 59 tabs.« less

  3. Evidence of offshore lake trout reproduction in Lake Huron

    USGS Publications Warehouse

    DeSorcie, Timothy J.; Bowen, Charles A.

    2003-01-01

    Six Fathom Bank-Yankee Reef, an offshore reef complex, was an historically important spawning area believed to represent some of the best habitat for the rehabilitation of lake trout Salvelinus namaycush in Lake Huron. Since 1986, lake trout have been stocked on these offshore reefs to reestablish self-sustaining populations. We sampled with beam trawls to determine the abundance of naturally reproduced age-0 lake trout on these offshore reefs during May-July in 1994-1998 and 2000-2002. In total, 123 naturally reproduced lake trout fry were caught at Six Fathom Bank, and 2 naturally reproduced lake trout fry were caught at nearby Yankee Reef. Our findings suggest that this region of Lake Huron contains suitable habitat for lake trout spawning and offers hope that lake trout rehabilitation can be achieved in the main basin of Lake Huron.

  4. Auckland City Hospital's ortho-geriatric service: an audit of patients aged over 65 with fractured neck of femur.

    PubMed

    Fergus, Lucy; Cutfield, Greer; Harris, Roger

    2011-06-24

    The process of care of older patients with fractured neck of femur at Auckland City Hospital has recently changed with selected patients "fast-tracked" as soon as possible postoperatively to a specialised Older People's Health (OPH) ward. The aims of this study were: to evaluate patient characteristics; to analyse process of care; to compare outcomes in those "fast-tracked" patients with those receiving usual care; and to compare this information with previous data from Auckland City Hospital and other centres in New Zealand. Prospective case record audit of patients with fractured neck of femur aged 65 years and over admitted under Orthopaedics over a 4-month period. 115 patients were audited; mean age was 84 years, 77% were female. Inpatient mortality was 5%. Twenty-four percent of patients had surgery within 24 hours of admission. Of those who did not have surgery within 24 hours, 39% were awaiting operating theatre availability. Median overall length of stay (LOS) was 27 days. Eighty-four percent of patients were transferred to Older Peoples Health. Considering all patients, 70% of those living at home pre-fracture returned home on discharge. However, only 26% of those in Rest Home returned to Rest Home. Overall, 35% of patients were discharged to a higher level of care. Forty-four percent of the group were able to walk unaided prior to hip fracture, but only 1% on discharge. Forty-three patients were "fast-tracked" to Older Peoples Health. Their median overall LOS was 23 days compared to 28 days for those receiving usual care. This was due to the shorter time in Orthopaedics. Thirty-three percent of this group went to a higher level of care on discharge compared to 35% in the group that received usual care. Many patients experience a delay to surgery for non-medical reasons. The percentage transferred to Older Peoples Health is high. Fast-tracking to Older Peoples Health shortens overall length of stay due to fewer days in Orthopaedics. Many patients require a

  5. Lake Nasser and Toshka Lakes, Egypt

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Lake Nasser (center) and the Toshka Lakes (center left) glow emerald green and black in this MODIS true-color image acquired March 8, 2002. Located on and near the border of Egypt and Norther Sudan, these lakes are an oasis of water in between the Nubian (lower right) and Libyan Deserts (upper left). Also visible are the Red Sea (in the upper right) and the Nile River (running north from Lake Nasser). Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  6. Auckland City Hospital's Ortho-Geriatric Service: an audit of patients aged over 65 with fractured neck of femur.

    PubMed

    Wimalasena, Bodhi; Harris, Roger

    2016-07-01

    The aims of this audit were to collect the Minimum Data Set outlined by the Australia New Zealand Hip Fracture Registry (ANZHFR), assess patient characteristics, analyse process of care, and evaluate how this compares to NICE guidelines for hip fracture care, as well as to Auckland Hospital data from 2007. Retrospective case record audit of patients with fractured neck of femur aged 65 years and over admitted under Orthopaedics over a 4-month period in 2013. Ninety-one patients were audited; mean age was 83 years, 68% were female. Both inpatient and 30-day mortality was 5%. 120-day mortality was 15%. Seventy-six percent of patients were admitted from ED within the national health target prescribed period of 6 hours. Only one patient was treated non-surgically. Eighty-six percent had surgery within 48 hours of admission. Eighty-two percent of patients had rehabilitation and treatment by Older People's Health. Of those living at home pre-fracture, 76% returned home on discharge. Thirty-seven percent of patients were able to walk unaided prior to hip fracture, but only 1% on discharge. Average overall length of stay was 22 days. Bisphosphonates were prescribed for 56% of patients. Compared to 2007, Auckland City Hospital has demonstrated a significant improvement in the rate of provision of timely surgery for hip fracture patients. Most patients are receiving the guideline recommended fracture-specific surgical interventions. The assessment and treatment of osteoporosis needs further attention.

  7. Dietary intakes of Pacific, Māori, Asian and European adolescents: the Auckland High School Heart Survey.

    PubMed

    Sluyter, John D; Schaaf, David; Metcalf, Patricia A; Scragg, Robert K R

    2010-02-01

    To compare dietary intakes of European, Māori, Pacific Island and Asian adolescents living in Auckland. A self-administered food frequency questionnaire was used to assess daily nutrient intakes of 2,549 14- to 21-year-old high-school students in Auckland (1,422 male and 1,127 female) in a cross-sectional survey carried out between 1997 and 1998. Compared with Europeans, Māori and Pacific Islanders consumed more energy per day. Carbohydrate, protein and fat intakes were higher in Māori and Pacific Islanders than in Europeans. Cholesterol intakes were lowest in Europeans and alcohol intakes were highest in Europeans and Māori. When nutrient intakes were expressed as their percentage contribution to total energy, many ethnic differences in nutrient intakes between Europeans and Māori or Pacific Islanders were eliminated. After adjustment for energy intake and age, Europeans ate the fewest eggs, and Pacific Islanders and Asians ate more servings of chicken and fish, and fewer servings of milk and cereal than Europeans. Compared to Europeans, Pacific Islanders consumed larger portion sizes for nearly every food item. There were marked differences in nutrient intakes between Pacific, Māori, Asian and European adolescents. Ethnic differences in food selections, frequency of food servings and portion sizes contribute to the differences in nutrient intakes between these ethnic groups. These differences generally matched those of other studies in children and adults from these ethnic groups. Interventions that reduce frequency of food consumption and serving sizes and promote less-fatty food choices in Māori and Pacific adolescents are needed. © 2010 The Authors. Journal Compilation © 2010 Public Health Association of Australia.

  8. Management of suspected acute coronary syndrome patients admitted to cardiology or non-cardiology services at Auckland City Hospital: implications for future national data collection.

    PubMed

    Wang, Tom Kai Ming; Chow, Kok-Lam; Lin, Aaron; Chataline, Alexei; White, Harvey; Dawes, Matthew; Gamble, Greg; Ellis, Chris

    2018-03-09

    To review the number, characteristics and clinical management of suspected ACS patients admitted to cardiology and non-cardiology services at Auckland City Hospital, to assess differences between these services and to assess the number who would potentially be enrolled in the All New Zealand Acute Coronary Syndrome (ACS) Quality Improvement Programme (ANZACS-QI) database. Auckland City Hospital patient data was extracted from the Australia and New Zealand ACS 'SNAPSHOT' audit, performed over 14 days in May 2012. There were 121 suspected ACS admissions to Auckland City hospital during the audit period, with 45 (37%) patients directly managed by the cardiology service, and 76 (63%) patients cared for by non-cardiology services. Based on the subsequent discharge diagnosis, the cardiology service had more patients with definite ACS than the non-cardiology services; 27/45 (60%) compared to 16/76 (21%), difference (95%CI) 39% (22-56), P<0.0001). Cardiology ACS patients were more likely to undergo echocardiography; 15/27 (56%) compared to 2/16 (13%), difference 42% (18-68), P=0.0089), coronary angiography; 21/27 (78%) compared to 3/16 (19%), difference (95%CI) 59% (34-84), P=0.0003), coronary revascularisation; 18/27 (67%) compared to 3/16 (19%), difference (95%CI) 48% (22-74), P=0.004, and be discharged on two antiplatelet agents; 18/26 (69%) compared to 3/15 (20%), difference (95%CI) 49% (22-76), P=0.0036, or an ACEI/ARB; 20/26 (77%) compared to 5/15 (33%), difference (95%CI) 44% (15-72), P=0.0088. In patients with a discharge diagnosis of definite ACS, those managed by non-cardiology services were less likely to receive guideline-recommended investigations, and management, in this relatively small cohort study. About one-third of all ACS patients are managed by non-cardiology services and would not be recorded by the ANZACS-QI database.

  9. Lake whitefish diet, condition, and energy density in Lake Champlain and the lower four Great Lakes following dreissenid invasions

    USGS Publications Warehouse

    Herbst, Seth J.; Marsden, J. Ellen; Lantry, Brian F.

    2013-01-01

    Lake Whitefish Coregonus clupeaformis support some of the most valuable commercial freshwater fisheries in North America. Recent growth and condition decreases in Lake Whitefish populations in the Great Lakes have been attributed to the invasion of the dreissenid mussels, zebra mussels Dreissena polymorpha and quagga mussels D. bugensis, and the subsequent collapse of the amphipod, Diporeia, a once-abundant high energy prey source. Since 1993, Lake Champlain has also experienced the invasion and proliferation of zebra mussels, but in contrast to the Great Lakes, Diporeia were not historically abundant. We compared the diet, condition, and energy density of Lake Whitefish from Lake Champlain after the dreissenid mussel invasion to values for those of Lake Whitefish from Lakes Michigan, Huron, Erie, and Ontario. Lake Whitefish were collected using gill nets and bottom trawls, and their diets were quantified seasonally. Condition was estimated using Fulton's condition factor (K) and by determining energy density. In contrast to Lake Whitefish from some of the Great Lakes, those from Lake Champlain Lake Whitefish did not show a dietary shift towards dreissenid mussels, but instead fed primarily on fish eggs in spring, Mysis diluviana in summer, and gastropods and sphaeriids in fall and winter. Along with these dietary differences, the condition and energy density of Lake Whitefish from Lake Champlain were high compared with those of Lake Whitefish from Lakes Michigan, Huron, and Ontario after the dreissenid invasion, and were similar to Lake Whitefish from Lake Erie; fish from Lakes Michigan, Huron, and Ontario consumed dreissenids, whereas fish from Lake Erie did not. Our comparisons of Lake Whitefish populations in Lake Champlain to those in the Great Lakes indicate that diet and condition of Lake Champlain Lake Whitefish were not negatively affected by the dreissenid mussel invasion.

  10. Spatial patterns in PCB concentrations of Lake Michigan lake trout

    USGS Publications Warehouse

    Madenjian, Charles P.; DeSorcie, Timothy J.; Stedman, Ralph M.; Brown, Edward H.; Eck, Gary W.; Schmidt, Larry J.; Hesselberg, Robert J.; Chernyak, Sergei M.; Passino-Reader, Dora R.

    1999-01-01

    Most of the PCB body burden in lake trout (Salvelinus namaycush) of the Great Lakes is from their food. PCB concentrations were determined in lake trout from three different locations in Lake Michigan during 1994–1995, and lake trout diets were analyzed at all three locations. The PCB concentrations were also determined in alewife (Alosa pseudoharengus), rainbow smelt (Osmerus mordax), bloater (Coregonus hoyi), slimy sculpin (Cottus cognatus), and deepwater sculpin (Myoxocephalus thompsoni), five species of prey fish eaten by lake trout in Lake Michigan, at three nearshore sites in the lake. Despite the lack of significant differences in the PCB concentrations of alewife, rainbow smelt, bloater, slimy sculpin, and deepwater sculpin from the southeastern nearshore site near Saugatuck (Michigan) compared with the corresponding PCB concentrations from the northwestern nearshore site near Sturgeon Bay (Wisconsin), PCB concentrations in lake trout at Saugatuck were significantly higher than those at Sturgeon Bay. The difference in the lake trout PCB concentrations between Saugatuck and Sturgeon Bay could be explained by diet differences. The diet of lake trout at Saugatuck was more concentrated in PCBs than the diet of Sturgeon Bay lake trout, and therefore lake trout at Saugatuck were more contaminated in PCBs than Sturgeon Bay lake trout. These findings were useful in interpreting the long-term monitoring series for contaminants in lake trout at both Saugatuck and the Wisconsin side of the lake.

  11. Sleep disorders, depression, anxiety and satisfaction with life among young adults: a survey of university students in Auckland, New Zealand.

    PubMed

    Samaranayake, Chinthaka B; Arroll, Bruce; Fernando, Antonio T

    2014-08-01

    Sleep symptoms, depression and anxiety often coexist and tertiary students are a population group that are increasingly recognised to be at risk. However the rates of these conditions in the New Zealand population are poorly understood. The aim of this study was to determine the rates of sleep disorders, depression and anxiety, and identify correlations between satisfactions with life among university students in Auckland. Auckland Sleep Questionnaire (ASQ) was administered to undergraduate students from six schools of The University of Auckland. The different types of sleep disorders were calculated for the students who reported a significant sleep problem lasting more than 1 month. The rate of depression, anxiety and substance use as well as the satisfaction with life scale scores were also calculated for the whole cohort. A total of 1933 students were invited to participate and 66.8% completed the questionnaire. The median age was 20 years (range 16-38) and women represented 63.9% of the total group. A total of 39.4% of the students surveyed reported having significant sleep symptoms lasting longer than 1 month. The most prevalent causes for sleep symptoms were depression and anxiety. Delayed sleep phase disorder was found in 24.9% of students and parasomnias were reported by 12.4%. Depression and anxiety were present in 17.3% and 19.7% of the total group respectively, and 7.3% of students had thoughts of "being better off dead" or self-harm. A total of 15.5% students were found to have a CAGE score greater than or equal to 2 and 9.3% reported using recreational drugs in the last 3 months. Moderate negative correlations between SWLS scores and depression and anxiety were found (r=-0.45 and r=-0.37 respectively). A large number of university students are suffering from significant sleep symptoms. Mood disorders, substance use, and circadian rhythm disorders can greatly contribute to sleep difficulties in this population group. The study also showed that harmful

  12. Potential strategies for recovery of lake whitefish and lake herring stocks in eastern Lake Erie

    USGS Publications Warehouse

    Oldenburg, K.; Stapanian, M.A.; Ryan, P.A.; Holm, E.

    2007-01-01

    Lake Erie sustained large populations of ciscoes (Salmonidae: Coregoninae) 120 years ago. By the end of the 19th century, abundance of lake whitefish (Coregonus clupeaformis) had declined drastically. By 1925, the lake herring (a cisco) population (Coregonus artedii) had collapsed, although a limited lake herring fishery persisted in the eastern basin until the 1950s. In the latter part of the 20th century, the composition of the fish community changed as oligotrophication proceeded. Since 1984, a limited recovery of lake whitefish has occurred, however no recovery was evident for lake herring. Current ecological conditions in Lake Erie probably will not inhibit recovery of the coregonine species. Recovery of walleye (Sander vitreus) and efforts to rehabilitate the native lake trout (Salvelinus namaycush) in Lake Erie will probably assist recovery because these piscivores reduce populations of alewife (Alosa psuedoharengus) and rainbow smelt (Osmerus mordax), which inhibit reproductive success of coregonines. Although there are considerable spawning substrates available to coregonine species in eastern Lake Erie, eggs and fry would probably be displaced by storm surge from most shoals. Site selection for stocking or seeding of eggs should consider the reproductive life cycle of the stocked fish and suitable protection from storm events. Two potential sites in the eastern basin have been identified. Recommended management procedures, including commercial fisheries, are suggested to assist in recovery. Stocking in the eastern basin of Lake Erie is recommended for both species, as conditions are adequate and the native spawning population in the eastern basin is low. For lake herring, consideration should be given to match ecophenotypes as much as possible. Egg seeding is recommended. Egg seeding of lake whitefish should be considered initially, with fingerling or yearling stocking suggested if unsuccessful. Spawning stocks of whitefish in the western basin of Lake

  13. Glacial lake inventory and lake outburst potential in Uzbekistan.

    PubMed

    Petrov, Maxim A; Sabitov, Timur Y; Tomashevskaya, Irina G; Glazirin, Gleb E; Chernomorets, Sergey S; Savernyuk, Elena A; Tutubalina, Olga V; Petrakov, Dmitriy A; Sokolov, Leonid S; Dokukin, Mikhail D; Mountrakis, Giorgos; Ruiz-Villanueva, Virginia; Stoffel, Markus

    2017-08-15

    Climate change has been shown to increase the number of mountain lakes across various mountain ranges in the World. In Central Asia, and in particular on the territory of Uzbekistan, a detailed assessment of glacier lakes and their evolution over time is, however lacking. For this reason we created the first detailed inventory of mountain lakes of Uzbekistan based on recent (2002-2014) satellite observations using WorldView-2, SPOT5, and IKONOS imagery with a spatial resolution from 2 to 10m. This record was complemented with data from field studies of the last 50years. The previous data were mostly in the form of inventories of lakes, available in Soviet archives, and primarily included localized in-situ data. The inventory of mountain lakes presented here, by contrast, includes an overview of all lakes of the territory of Uzbekistan. Lakes were considered if they were located at altitudes above 1500m and if lakes had an area exceeding 100m 2 . As in other mountain regions of the World, the ongoing increase of air temperatures has led to an increase in lake number and area. Moreover, the frequency and overall number of lake outburst events have been on the rise as well. Therefore, we also present the first outburst assessment with an updated version of well-known approaches considering local climate features and event histories. As a result, out of the 242 lakes identified on the territory of Uzbekistan, 15% are considered prone to outburst, 10% of these lakes have been assigned low outburst potential and the remainder of the lakes have an average level of outburst potential. We conclude that the distribution of lakes by elevation shows a significant influence on lake area and hazard potential. No significant differences, by contrast, exist between the distribution of lake area, outburst potential, and lake location with respect to glaciers by regions. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Spectrum and Sensitivity of Bacterial Keratitis Isolates in Auckland.

    PubMed

    Marasini, S; Swift, S; Dean, S J; Ormonde, S E; Craig, J P

    2016-01-01

    Background. The bacteria isolated from severe cases of keratitis and their antibiotic sensitivity are recognised to vary geographically and over time. Objectives. To identify the most commonly isolated bacteria in keratitis cases admitted over a 24-month period to a public hospital in Auckland, New Zealand, and to investigate in vitro sensitivity to antibiotics. Methods. Hospital admissions for culture-proven bacterial keratitis between January 2013 and December 2014 were identified. Laboratory records of 89 culture positive cases were retrospectively reviewed and antibiotic sensitivity patterns compared with previous studies from other NZ centres. Results. From 126 positive cultures, 35 species were identified. Staphylococcus was identified to be the most common isolate (38.2%), followed by Pseudomonas (21.3%). Over the last decade, infection due to Pseudomonas species, in the same setting, has increased (p ≤ 0.05). Aminoglycosides, cefazolin, ceftazidime, erythromycin, tetracycline, and doxycycline were 100% effective against tested isolates in vitro. Amoxicillin (41.6%), cefuroxime (33.3%), and chloramphenicol (94.7%) showed reduced efficacy against Gram-negative bacteria, whereas penicillin (51%) and ciprofloxacin (98.8%) showed reduced efficacy against Gram-positive bacteria. Conclusions. Despite a shift in the spectrum of bacterial keratitis isolates, antibiotic sensitivity patterns have generally remained stable and show comparability to results within the last decade from NZ centres.

  15. Spatio-volumetric hazard estimation in the Auckland volcanic field

    NASA Astrophysics Data System (ADS)

    Bebbington, Mark S.

    2015-05-01

    The idea of a volcanic field `boundary' is prevalent in the literature, but ill-defined at best. We use the elliptically constrained vents in the Auckland Volcanic Field to examine how spatial intensity models can be tested to assess whether they are consistent with such features. A means of modifying the anisotropic Gaussian kernel density estimate to reflect the existence of a `hard' boundary is then suggested, and the result shown to reproduce the observed elliptical distribution. A new idea, that of a spatio-volumetric model, is introduced as being more relevant to hazard in a monogenetic volcanic field than the spatiotemporal hazard model due to the low temporal rates in volcanic fields. Significant dependencies between the locations and erupted volumes of the observed centres are deduced, and expressed in the form of a spatially-varying probability density. In the future, larger volumes are to be expected in the `gaps' between existing centres, with the location of the greatest forecast volume lying in the shipping channel between Rangitoto and Castor Bay. The results argue for tectonic control over location and magmatic control over erupted volume. The spatio-volumetric model is consistent with the hypothesis of a flat elliptical area in the mantle where tensional stresses, related to the local tectonics and geology, allow decompressional melting.

  16. 23 years of managing diabetic ketoacidosis at Auckland Hospital

    PubMed

    Braatvedt, Geoffrey; Tekiteki, Amelia; Britton, Holly; Wallace, John; Khanolkar, Manish

    2017-02-17

    To examine the length of stay and need for intensive care of people admitted with diabetic ketoacidosis (DKA) to a single centre between 1988 and 2011. Patients aged ≥15 years admitted for the first time with DKA (plasma glucose ≥ 10mmol/L and a bicarbonate concentration ≤15mmol/L and a pH <7.35, and raised plasma or urine ketones or anion gap) to Auckland City Hospital from 1988-2011 were identified retrospectively. The patients were divided into four cohorts (1988-1996; 1997-2001; 2002-2006; 2007-2011). Over this time period there was no significant change to the insulin infusion protocol. There were 576 admissions with DKA in 388 people over the 23 years. The mean age of the patients and glucose concentration at presentation to hospital fell significantly over time. The admission pH and bicarbonate concentration was higher in more recent cohorts. The length of stay and need for intensive care admission fell significantly over time, but the number of patients subsequently readmitted with DKA remained high. In-hospital mortality remained low. DKA remains an important reason for admission to this hospital, but the severity of DKA at presentation has reduced over time. The need for intensive care admission and length of stay has fallen dramatically.

  17. Spectrum and Sensitivity of Bacterial Keratitis Isolates in Auckland

    PubMed Central

    Swift, S.; Dean, S. J.; Ormonde, S. E.

    2016-01-01

    Background. The bacteria isolated from severe cases of keratitis and their antibiotic sensitivity are recognised to vary geographically and over time. Objectives. To identify the most commonly isolated bacteria in keratitis cases admitted over a 24-month period to a public hospital in Auckland, New Zealand, and to investigate in vitro sensitivity to antibiotics. Methods. Hospital admissions for culture-proven bacterial keratitis between January 2013 and December 2014 were identified. Laboratory records of 89 culture positive cases were retrospectively reviewed and antibiotic sensitivity patterns compared with previous studies from other NZ centres. Results. From 126 positive cultures, 35 species were identified. Staphylococcus was identified to be the most common isolate (38.2%), followed by Pseudomonas (21.3%). Over the last decade, infection due to Pseudomonas species, in the same setting, has increased (p ≤ 0.05). Aminoglycosides, cefazolin, ceftazidime, erythromycin, tetracycline, and doxycycline were 100% effective against tested isolates in vitro. Amoxicillin (41.6%), cefuroxime (33.3%), and chloramphenicol (94.7%) showed reduced efficacy against Gram-negative bacteria, whereas penicillin (51%) and ciprofloxacin (98.8%) showed reduced efficacy against Gram-positive bacteria. Conclusions. Despite a shift in the spectrum of bacterial keratitis isolates, antibiotic sensitivity patterns have generally remained stable and show comparability to results within the last decade from NZ centres. PMID:27213052

  18. Hydroclimate of North Island of New Zealand during the last 45,000 Years.

    NASA Astrophysics Data System (ADS)

    Piatrunia, N.; Shanahan, T. M.; Augustinus, P. M.; Atkins, D.; Huang, Y.

    2016-12-01

    Southern hemisphere climate variability and its connection with past changes in the northern hemisphere remains poorly understood. While climate conditions in the polar regions are well-studied, the spatial and temporal resolution of existing southern hemisphere mid-latitude records is limited. New Zealand provides an ideal location for the preservation of high-resolution multi-proxy records in lacustrine cores and the analysis of mid-latitude climate throughout the Holocene and beyond. Here, we present a 45,000-year record of plant wax dD (a proxy for precipitation) and branched GDGT-derived temperatures from Lake Pupuke, on the North Island of New Zealand (36°78.30'S, 174°76.70'E) in order to better constrain changes in the climate of the southern hemisphere mid latitudes. We find that during the last glacial the North Island experienced colder and drier conditions, with temperatures that were > 3.5°C cooler than those experienced during the Holocene. Plant wax dD values vary substantially during the glacial interval, with the most enriched values occurring at 21 kyr and 24.5 kyr. Shifts to more arid conditions during these intervals were associated with intensification of the SH westerlies and the northward migration of the subtropical (STF), subpolar (SPF) and polar fronts (PF). The Lake Pupuke record suggests that deglaciation of New Zealand initiated at 18 kyr, with gradual increases in temperature. dD values continue to decrease gradually through the deglaciation, suggesting a linear response of precipitation to insolation forcing. However, temperature increases abruptly during the Bolling-Allerod warming - coincident with changes in the northern hemisphere. Together, these data suggest a decoupling of the controls on deglacial circulation and temperature changes, with important implications for our understanding of the mechanisms of deglacial climate changes in the southern hemisphere mid-latitudes and the interpretation of proxy records from this region.

  19. Progress toward lake trout restoration in Lake Michigan

    USGS Publications Warehouse

    Holey, Mark E.; Rybicki, Ronald W.; Eck, Gary W.; Brown, Edward H.; Marsden, J. Ellen; Lavis, Dennis S.; Toneys, Michael L.; Trudeau, Tom N.; Horrall, Ross M.

    1995-01-01

    Progress toward lake trout restoration in Lake Michigan is described through 1993. Extinction of the native lake trout fishery by sea lamprey predation, augmented by exploitation and habitat destruction, resulted in an extensive stocking program of hatchery-reared lake trout that began in 1965. Sea lamprey abundance was effectively controlled using selective chemical toxicants. The initial stocking produced a measurable wild year class of lake trout by 1976 in Grand Traverse Bay, but failed to continue probably due to excessive exploitation. The overall lack of successful reproduction lakewide by the late 1970s led to the development and implementation in 1985 of a focused inter-agency lakewide restoration plan by a technical committee created through the Lake Committee structure of the Great Lakes Fishery Commission. Strategies implemented in 1985 by the plan included setting a 40% total mortality goal lakewide, creating two large refuges designed to encompass historically the most productive spawning habitat and protect trout stocked over their home range, evaluating several lake trout strains, and setting stocking priorities throughout the lake. Target levels for stocking in the 1985 Plan have never been reached, and are much less than the estimated lakewide recruitment of yearlings by the native lake trout stocks. Since 1985, over 90% of the available lake trout have been stocked over the best spawning habitat, and colonization of the historically productive offshore reefs has occurred. Concentrations of spawning lake trout large enough for successful reproduction, based on observations of successful hatchery and wild stocks, have developed at specific reefs. Continued lack of recruitment at these specific sites suggests that something other than stotk abundance has limited success. Poor survival of lake trout eggs, assumed to be related to contaminant burden, occurred in the late 1970s and early 1980s, but survival has since increased to equal survival in the

  20. Lake trout rehabilitation in Lake Huron

    USGS Publications Warehouse

    Eshenroder, Randy L.; Payne, N. Robert; Johnson, James E.; Bowen, Charles; Ebener, Mark P.

    1995-01-01

    Efforts to restore lake trout (Salvelinus namaycush) in Lake Huron after their collapse in the 1940s were underway in the early 1970s with completion of the first round of lampricide applications in tributary streams and the stocking of several genotypes. We assess results of rehabilitation and establish a historical basis for comparison by quantifying the catch of spawning lake trout from Michigan waters in 1929-1932. Sixty-eight percent of this catch occurred in northern waters (MH-1) and most of the rest (15%) was from remote reefs in the middle of the main basin. Sea lampreys (Petromyzon marinus) increased in the early 1980s in the main basin and depressed spawning populations of lake trout. This increase was especially severe in northern waters and appeared to be associated with untreated populations in the St. Marys River. Excessive commercial fishing stemming from unresolved treaty rights also contributed to loss of spawning fish in northern Michigan waters. Seneca-strain lake trout did not appear to be attacked by sea lampreys until they reached a size > 532 mm. At sizes > 632 mm, Seneca trout were 40-fold more abundant than the Marquette strain in matched-planting experiments. Natural reproduction past the fry stage has occurred in Thunder Bay and South Bay, but prospects for self-sustaining populations of lake trout in the main basin are poor because sea lampreys are too abundant, only one side of the basin is stocked, and stocking is deferred to allow commercial gillnetting in areas where most of the spawning occurred historically. Backcross lake trout, a lake trout x splake (s. Fontinalis x s. Namaycush) hybrid, did not reproduce in Georgian Bay, but this genotype is being replaced with pure-strain lake trout, whose early performance appears promising.

  1. Evolution of alkaline lakes - Lake Van case study

    NASA Astrophysics Data System (ADS)

    Tillman Meyer, Felix; Viehberg, Finn; Bahroun, Sonya; Wolf, Annabel; Immenhauser, Adrian; Kwiecien, Ola

    2017-04-01

    Lake Van in Eastern Anatolia (Turkey) is the largest terminal soda lake on Earth. The lake sedimentary profile covers ca. 600 ka (Stockhecke et al. 2014) Based on lithological changes, the presence of freshwater microfossils and close-to-freshwater pH value in the pore water, members of ICDP PALEOVAN concluded that Lake Van might have started as an open lake. Here we show paleontological and geochemical evidence in favour of this idea and constrain the time, when Lake Van likely transformed into a closed lake. Additionally we provide the first conceptual model of how this closure may have happened. Our archives of choice are inorganic and biogenic carbonates, separated by wet sieving. We identified microfossil assemblages (fraction > 125 µm) and performed high-resolution oxygen isotope (delta18O) and elemental (Mg/Ca, Sr/Ca) analyses of the fraction < 63 µm assuming that it represents only carbonates precipitating in the water column. Microfossil assemblage consists of three different species of ostracods (Candona spp, Loxoconcha sp, Amnicythere spp.), diatoms, gastropods and bivalves. Brakish-water ostracods, Loxoconcha sp and Amnicythere sp occur more often after 530 ka. Additionaly, Loxoconcha sp is a shallow-water species relaying on plants growing in the photic zone as food supply. These two aspects point to an increasing salinity in a shallowing lake. The delta18O values of inorganic carbonates are relatively low during the initial phase of Lake Van and increase abruptly (ca. 7‰) after 530 ka BP. At approximately the same time combination of Sr/Ca and Mg/Ca data suggest first occurrence of aragonite. Again, these findings suggest geochemical changes of the lake water concurrent with transition documented by microfossils. Comparison between Lake Van and Lake Ohrid (Lacey et al. 2016) delta18O data, precludes regional climate change (e.g.: increased evaporation) as the main driver of observed changes. With no evidence for increased volcanic or tectonic

  2. Embryotoxicity of an extract from Great Lakes lake trout to rainbow trout and lake trout

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wright, P.J.; Tillitt, D.E.

    1995-12-31

    Aquatic ecosystems such as the Great Lakes are known to be contaminated with chemicals that are toxic to fish. However, the role of these contaminants in reproductive failures of fishes, such as lake trout recruitment, has remained controvertible. It was the objective to evaluate dioxin-like embryotoxicity of a complex mixture of chemicals and predict their potential to cause the lack of recruitment in Great Lakes lake trout. Graded doses of a complex environmental extract were injected into eggs of both rainbow trout and lake trout. The extract was obtained from whole adult lake trout collected from Lake Michigan in 1988.more » The extract was embryotoxic in rainbow trout, with LD50 values for Arlee strain and Erwin strain of 33 eggEQ and 14 eggEQ respectively. The LOAEL for hemorrhaging, yolk-sac edema, and craniofacial deformities in rainbow trout were 2, 2, and 4 eggEQ, respectively. Subsequent injections of the extract into lake trout eggs were likewise embryotoxic, with an LD50 value of 7 eggEQ. The LOAEL values for the extract in lake trout for hemorrhaging, yolk-sac edema, and craniofacial deformities were 0.1, 1, and 2 eggEQ, respectively. The current levels of contaminants in lake trout eggs are above the threshold for hemorrhaging and yolk-sac edema. The results also support the use of an additive model of toxicity to quantify PCDDs, PCDFs, Non-o-PCBs, and Mono-o-PCBs in relation to early life stage mortality in Lake Michigan lake trout.« less

  3. Hydrogeologic Controls on Lake Level at Mountain Lake, Virginia

    NASA Astrophysics Data System (ADS)

    Roningen, J. M.; Burbey, T. J.

    2011-12-01

    Mountain Lake in Giles County, Virginia has a documented history of severe natural lake-level changes involving groundwater seepage that extend over the past 4200 years. Featured in the 1986 movie Dirty Dancing, the natural lake dried up completely in September 2008 and levels have not yet recovered. A hydrogeologic investigation was undertaken in an effort to determine the factors influencing lake level changes. A daily water balance, dipole-dipole electrical resistivity surveying, well logging and chemical sampling have shed light on: 1) the influence of a fault not previously discussed in literature regarding the lake, 2) the seasonal response to precipitation of a forested first-order drainage system in fractured rock, and 3) the possibility of flow pathways related to karst features. Geologic controls on lake level were investigated using several techniques. Geophysical surveys using dipole-dipole resistivity located possible subsurface flowpaths both to and from the lake. Well logs, lineament analysis, and joint sampling were used to assess structural controls on lake hydrology. Major ions were sampled at wells, springs, streams, and the lake to evaluate possible mixing of different sources of water in the lake. Groundwater levels were monitored for correlation to lake levels, rainfall events, and possible seismic effects. The hydrology of the lake was quantified with a water balance on a daily time step. Results from the water balance indicate steady net drainage and significant recharge when vegetation is dormant, particularly during rain-on-snow melt events. The resistivity survey reveals discrete areas that represent flow pathways from the lake, as well as flowpaths to springs upgradient of the lake located in the vicinity of the fault. The survey also suggests that some flowpaths may originate outside of the topographic watershed of the lake. Chemical evidence indicates karst may underlie the lakebed. Historical data suggest that artificial intervention

  4. Lake-level frequency analysis for Devils Lake, North Dakota

    USGS Publications Warehouse

    Wiche, Gregg J.; Vecchia, Aldo V.

    1996-01-01

    Two approaches were used to estimate future lake-level probabilities for Devils Lake. The first approach is based on an annual lake-volume model, and the second approach is based on a statistical water mass-balance model that generates seasonal lake volumes on the basis of seasonal precipitation, evaporation, and inflow. Autoregressive moving average models were used to model the annual mean lake volume and the difference between the annual maximum lake volume and the annual mean lake volume. Residuals from both models were determined to be uncorrelated with zero mean and constant variance. However, a nonlinear relation between the residuals of the two models was included in the final annual lakevolume model.Because of high autocorrelation in the annual lake levels of Devils Lake, the annual lake-volume model was verified using annual lake-level changes. The annual lake-volume model closely reproduced the statistics of the recorded lake-level changes for 1901-93 except for the skewness coefficient. However, the model output is less skewed than the data indicate because of some unrealistically large lake-level declines. The statistical water mass-balance model requires as inputs seasonal precipitation, evaporation, and inflow data for Devils Lake. Analysis of annual precipitation, evaporation, and inflow data for 1950-93 revealed no significant trends or long-range dependence so the input time series were assumed to be stationary and short-range dependent.Normality transformations were used to approximately maintain the marginal probability distributions; and a multivariate, periodic autoregressive model was used to reproduce the correlation structure. Each of the coefficients in the model is significantly different from zero at the 5-percent significance level. Coefficients relating spring inflow from one year to spring and fall inflows from the previous year had the largest effect on the lake-level frequency analysis.Inclusion of parameter uncertainty in the model

  5. Lake-level frequency analysis for Devils Lake, North Dakota

    USGS Publications Warehouse

    Wiche, Gregg J.; Vecchia, Aldo V.

    1995-01-01

    Two approaches were used to estimate future lake-level probabilities for Devils Lake. The first approach is based on an annual lake-volume model, and the second approach is based on a statistical water mass-balance model that generates seasonal lake volumes on the basis of seasonal precipitation, evaporation, and inflow.Autoregressive moving average models were used to model the annual mean lake volume and the difference between the annual maximum lake volume and the annual mean lake volume. Residuals from both models were determined to be uncorrelated with zero mean and constant variance. However, a nonlinear relation between the residuals of the two models was included in the final annual lake-volume model.Because of high autocorrelation in the annual lake levels of Devils Lake, the annual lakevolume model was verified using annual lake-level changes. The annual lake-volume model closely reproduced the statistics of the recorded lake-level changes for 1901-93 except for the skewness coefficient However, the model output is less skewed than the data indicate because of some unrealistically large lake-level declines.The statistical water mass-balance model requires as inputs seasonal precipitation, evaporation, and inflow data for Devils Lake. Analysis of annual precipitation, evaporation, and inflow data for 1950-93 revealed no significant trends or long-range dependence so the input time series were assumed to be stationary and short-range dependent.Normality transformations were used to approximately maintain the marginal probability distributions; and a multivariate, periodic autoregressive model was used to reproduce the correlation structure. Each of the coefficients in the model is significantly different from zero at the 5-percent significance level. Coefficients relating spring inflow from one year to spring and fall inflows from the previous year had the largest effect on the lake-level frequency analysis.Inclusion of parameter uncertainty in the model

  6. Lake trout in northern Lake Huron spawn on submerged drumlins

    USGS Publications Warehouse

    Riley, Stephen C.; Binder, Thomas; Wattrus, Nigel J.; Faust, Matthew D.; Janssen, John; Menzies, John; Marsden, J. Ellen; Ebener, Mark P.; Bronte, Charles R.; He, Ji X.; Tucker, Taaja R.; Hansen, Michael J.; Thompson, Henry T.; Muir, Andrew M.; Krueger, Charles C.

    2014-01-01

    Recent observations of spawning lake trout Salvelinus namaycush near Drummond Island in northern Lake Huron indicate that lake trout use drumlins, landforms created in subglacial environments by the action of ice sheets, as a primary spawning habitat. From these observations, we generated a hypothesis that may in part explain locations chosen by lake trout for spawning. Most salmonines spawn in streams where they rely on streamflows to sort and clean sediments to create good spawning habitat. Flows sufficient to sort larger sediment sizes are generally lacking in lakes, but some glacial bedforms contain large pockets of sorted sediments that can provide the interstitial spaces necessary for lake trout egg incubation, particularly if these bedforms are situated such that lake currents can penetrate these sediments. We hypothesize that sediment inclusions from glacial scavenging and sediment sorting that occurred during the creation of bedforms such as drumlins, end moraines, and eskers create suitable conditions for lake trout egg incubation, particularly where these bedforms interact with lake currents to remove fine sediments. Further, these bedforms may provide high-quality lake trout spawning habitat at many locations in the Great Lakes and may be especially important along the southern edge of the range of the species. A better understanding of the role of glacially-derived bedforms in the creation of lake trout spawning habitat may help develop powerful predictors of lake trout spawning locations, provide insight into the evolution of unique spawning behaviors by lake trout, and aid in lake trout restoration in the Great Lakes.

  7. Lake sturgeon population characteristics in Rainy Lake, Minnesota and Ontario

    USGS Publications Warehouse

    Adams, W.E.; Kallemeyn, L.W.; Willis, D.W.

    2006-01-01

    Rainy Lake contains a native population of lake sturgeon Acipenser fulvescens that has been largely unstudied. The aims of this study were to document the population characteristics of lake sturgeon in Rainy Lake and to relate environmental factors to year-class strength for this population. Gill-netting efforts throughout the study resulted in the capture of 322 lake sturgeon, including 50 recaptures. Lake sturgeon in Rainy Lake was relatively plump and fast growing compared with a 32-population summary. Population samples were dominated by lake sturgeon between 110 and 150 cm total length. Age–structure analysis of the samples indicated few younger (<10 years) lake sturgeon, but the smallest gill net mesh size used for sampling was 102 mm (bar measure) and would not retain small sturgeon. Few lake sturgeon older than age 50 years were captured, and maximum age of sampled fish was 59 years. Few correlations existed between lake sturgeon year-class indices and both annual and monthly climate variables, except that mean June air temperature was positively correlated with year-class strength. Analysis of Rainy Lake water elevation and resulting lake sturgeon year-class strength indices across years yielded consistent but weak negative correlations between late April and early June, when spawning of lake sturgeon occurs. The baseline data collected in this study should allow Rainy Lake biologists to establish more specific research questions in the future.

  8. Rotavirus Infection in the Auckland Region After the Implementation of Universal Infant Rotavirus Vaccination: Impact on Hospitalizations and Laboratory Implications.

    PubMed

    McAuliffe, Gary N; Taylor, Susan L; Drinković, Dragana; Roberts, Sally A; Wilson, Elizabeth M; Best, Emma J

    2018-01-01

    In July 2014, New Zealand introduced universal infant vaccination with RotaTeq (Merk & Co.) administered as 3 doses at 6 weeks, 3 and 5 months of age. We sought to assess the impact of rotavirus vaccination on gastroenteritis (GE) hospitalizations in the greater Auckland region and analyze changes in rotavirus testing in the period around vaccine introduction. Hospitalizations, laboratory testing rates and methods were compared between the pre-vaccine period (2009-2013), post-vaccine period (January 2015 to December 2015) and year of vaccine introduction (2014). There was a 68% decline in rotavirus hospitalizations of children <5 years of age after vaccine introduction (from 258/100,000 to 83/100,000) and a 17% decline in all-cause gastroenteritis admissions (from 1815/100,000 to 1293/100,000). Reductions were also seen in pediatric groups too old to have received vaccine. Despite these changes, rotavirus testing rates in our region remained static in the year after vaccine introduction compared with the 2 prior years, and after vaccine introduction, we observed a high rate of false positives 19/58 (33%) in patients with reactive rotavirus tests. Rotavirus vaccine has had a significant early impact on gastroenteritis hospitalizations for children in the Auckland region. However, continued rotavirus testing at pre-vaccine rates risks generating false positive results. Laboratories and clinicians should consider reviewing their testing algorithms before vaccine introduction.

  9. Invasive Group A Streptococcal Infection and Vaccine Implications, Auckland, New Zealand

    PubMed Central

    Safar, Atheer; Stewart, Joanna; Trenholme, Adrian; Drinkovic, Dragana; Peat, Briar; Taylor, Susan; Read, Kerry; Roberts, Sally; Voss, Lesley

    2011-01-01

    We aimed to assess the effect of invasive group A streptococcal (GAS) infection and the potential effects of a multivalent GAS vaccine in New Zealand. During January 2005–December 2006, we conducted prospective population-based laboratory surveillance of Auckland residents admitted to all public hospitals with isolation of GAS from normally sterile sites. Using emm typing, we identified 225 persons with confirmed invasive GAS infection (median 53 years of age; range 0–97 years). Overall incidence was 8.1 cases per 100,00 persons per year (20.4/100,000/year for Maori and Pacific Islanders; 24.4/100,000/year for persons >65 years of age; 33/100,000/year for infants <1 year of age). Nearly half (49%) of all cases occurred in Auckland’s lowest socioeconomic quintile. Twenty-two persons died, for an overall case-fatality rate of 10% (63% for toxic shock syndrome). Seventy-four percent of patients who died had an underlying condition. To the population in our study, the proposed 26-valent vaccine would provide limited benefit. PMID:21749758

  10. Can formal collaborative methodologies improve quality in primary health care in New Zealand? Insights from the EQUIPPED Auckland Collaborative.

    PubMed

    Palmer, Celia; Bycroft, Janine; Healey, Kate; Field, Adrian; Ghafel, Mazin

    2012-12-01

    Auckland District Health Board was one of four District Health Boards to trial the Breakthrough Series (BTS) methodology to improve the management of long-term conditions in New Zealand, with support from the Ministry of Health. To improve clinical outcomes, facilitate planned care and promote quality improvement within participating practices in Auckland. Implementation of the Collaborative followed the improvement model / Institute for Healthcare Improvement methodology. Three topic areas were selected: system redesign, cardio-vascular disease/diabetes, and self-management support. An expert advisory group and the Improvement Foundation Australia helped guide project development and implementation. Primary Health Organisation facilitators were trained in the methodology and 15 practice teams participated in the three learning workshops and action periods over 12 months. An independent evaluation study using both quantitative and qualitative methods was conducted. Improvements were recorded in cardiovascular disease risk assessment, practice-level systems of care, self-management systems and follow-up and coordination for patients. Qualitative research found improvements in coordination and teamwork, knowledge of practice populations and understanding of managing long-term conditions. The Collaborative process delivered some real improvements in the systems of care for people with long-term conditions and a change in culture among participating practices. The findings suggest that by strengthening facilitation processes, improving access to comprehensive population audit tools and lengthening the time frame, the process has the potential to make significant improvements in practice. Other organisations should consider this approach when investigating quality improvement programmes.

  11. Lake Level Variation in Small Lakes: Not a Clear Picture

    NASA Astrophysics Data System (ADS)

    Starratt, S.

    2017-12-01

    Lake level is a useful tool for identifying regional changes in precipitation and evaporation. Due to the volume of water in large lakes, they may only record large-scale changes in water balance, while smaller lakes may record more subtle variations. However, the record of water level in small lakes is affected by a number of factors including elevation, bathymetry, nutrient load, and aquatic macrophyte abundance. The latest Quaternary diatom records from three small lakes with areas of <10 ha (Hobart Lake, OR, 1458 masl; Swamp Lake, CA, 1554 masl; Favre Lake, NV, 2899 masl) and a larger lake (Medicine Lake, CA, 2036 masl, 154 ha) were compared in this study. All the lakes have a deep central basin (>10 m) surrounded by a shallow (1-2 m) shelf. Changes in the abundance of diatoms representing different life habits (benthic, tychoplanktic, planktic) were used to identify lake level variation. Benthic taxa dominate the assemblage when only the central basin is occupied. As the shallow shelf is flooded, the abundance of tychoplanktic taxa increases. Planktic taxa increase with the establishment of stratification. Favre Lake presents the clearest indication of initial lake level rise (7600-5750 cal yr BP) and intermittent flooding of the shelf for the remainder of the record. Stratification appears to become established only in the last few hundred years. Higher nutrient levels in the early part of the Hobart Lake record lead to a nearly monotypic planktic assemblage which is replaced by a tychoplanktic-dominated assemblage as the lake floods the shelf at about 3500 cal yr BP. The last 500 years is dominated by benthic taxa associated with aquatic macrophytes. The consistent presence of planktic taxa in the Swamp Lake record suggests that the lake was stratified during most of its history, although slight variations in the relative abundances of planktic and tychoplanktic groups occur. The Medicine Lake record shows a gradual increase in planktic species between 11

  12. 78 FR 53675 - Safety Zone; Lake Erie Heritage Foundation, Battle of Lake Erie Reenactment; Lake Erie, Put-in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-30

    ...-AA00 Safety Zone; Lake Erie Heritage Foundation, Battle of Lake Erie Reenactment; Lake Erie, Put-in-Bay... temporary safety zone in the waters of Lake Erie in the vicinity of Put-In-Bay, OH. This safety zone is intended to restrict vessels from a portion of Lake Erie during Battle of Lake Erie Reenactment near Put-In...

  13. Medical students and debt: a survey of students at the School of Medicine, University of Auckland.

    PubMed

    Collins, M G

    1999-04-09

    To assess the extent of Auckland medical students' debt, the types of debt accrued and to establish data on part-time employment, income, parental support and living circumstances for these students. Medical students at the University of Auckland were asked to complete a written survey questionnaire, which was distributed in lecture classes for years 1-5 and by mail for year 6. The questionnaire asked about biographical data, types and amounts of debt, the use of student loan scheme money, employment, income, student allowances, parental financial support and living situation. Students not sent the survey by mail were informed about the survey several days prior to receiving it to enable them to collate the necessary financial information. Data entry was completed via an electronic scanning system and questionnaire responses were analysed using a tabular analysis of the various classes. There were 522 responses received, comprising 73% of students (48% male, 52% female). The major source of debt was to the Government student loan scheme (39% of students in year 1, rising to 75% in year 6). Average (median) debt to the Government loan scheme rises from $5000 in year 1 to $26,000 in year 6. Fourteen per cent of students receive a targeted student allowance and 30% have a part-time job. Average summer vacation earnings do not exceed $4000. Thirty-four percent receive no financial support from their parents and 18% receive support with some costs only. With the exceptions of students in year 1, more than 50% of students live away from home. Medical students are predominantly in debt to the Government student loan scheme and the level rises by approximately $5000 per year from year 1 to year 6. It is expected that these levels will increase in the future.

  14. Lake trout spawning habitat in the Six Fathom Bank-Yankee Reef lake trout sanctuary, Lake Huron

    USGS Publications Warehouse

    Edsall, Thomas A.; Brown, Charles L.; Kennedy, Gregory W.; Poe, Thomas P.

    1992-01-01

    Attempts to reestablish self-sustaining stocks of lake trout (Salvelinus namaycush) in the lower four Great Lakes, where the species was extinguished in the 1950s and 1960s, have been largely unsuccessful. To avoid many of the problems believed to be contributing to this failure, the fishery management community recently established several sanctuaries in the offshore waters of the Great Lakes where the development and protection of self-sustaining stocks of lake trout would be a primary management objective. One of these, the Six Fathom Bank-Yankee Reef sanctuary, was created in the south-central portion of Lake Huron. This sanctuary covers 168,000 ha and includes the shallower portions of the Six Fathom and Ipperwash scarps, which are major bathymetric features in the southern half of the lake. Historical accounts describe Six Fathom Bank as the most important lake trout spawning ground in the lake. Here we present the results of lake bed surveys conducted in the sanctuary with side-scan sonar, underwater videocamera systems, and a small research submarine. Our observations of the lake bed are consistent with what is known of the bedrock stratigraphy, glacial history, and karst geomorphology of the Lake Huron basin. Most of the loose rock we found seemed to be derived from local carbonate bedrock formations, although non-carbonate rock probably from Precambrian sources to the north was also present in some areas. Much of the bedrock and loose rock displayed karst solution features described for the Bruce Peninsula on the Ontario shoreline. Our surveys revealed substantial areas of lake bed at water depths of 20–36 m that resembled suitable spawning and fry production habitat for the shallow-water strains of lake trout that are the focus of the rehabilitation effort. Low mid-lake nutrient levels documented recently by others and the extremely high abundance of Mysis relicta (an important item in the diet of young lake trout) that we documented on Yankee Reef

  15. Lake-level variability and water availability in the Great Lakes

    USGS Publications Warehouse

    Wilcox, Douglas A.; Thompson, Todd A.; Booth, Robert K.; Nicholas, J.R.

    2007-01-01

    In this report, we present recorded and reconstructed (pre-historical) changes in water levels in the Great Lakes, relate them to climate changes of the past, and highlight major water-availability implications for storage, coastal ecosystems, and human activities. 'Water availability,' as conceptualized herein, includes a recognition that water must be available for human and natural uses, but the balancing of how much should be set aside for which use is not discussed. The Great Lakes Basin covers a large area of North America. The lakes capture and store great volumes of water that are critical in maintaining human activities and natural ecosystems. Water enters the lakes mostly in the form of precipitation and streamflow. Although flow through the connecting channels is a primary output from the lakes, evaporation is also a major output. Water levels in the lakes vary naturally on timescales that range from hours to millennia; storage of water in the lakes changes at the seasonal to millennial scales in response to lake-level changes. Short-term changes result from storm surges and seiches and do not affect storage. Seasonal changes are driven by differences in net basin supply during the year related to snowmelt, precipitation, and evaporation. Annual to millennial changes are driven by subtle to major climatic changes affecting both precipitation (and resulting streamflow) and evaporation. Rebounding of the Earth's surface in response to loss of the weight of melted glaciers has differentially affected water levels. Rebound rates have not been uniform across the basin, causing the hydrologic outlet of each lake to rise in elevation more rapidly than some parts of the coastlines. The result is a long-term change in lake level with respect to shoreline features that differs from site to site. The reconstructed water-level history of Lake Michigan-Huron over the past 4,700 years shows three major high phases from 2,300 to 3,300, 1,100 to 2,000, and 0 to 800

  16. Lake Life.

    ERIC Educational Resources Information Center

    Ohrn, Deborah Gore, Ed.

    1993-01-01

    This quarterly publication of the State Historical Society of Iowa features articles and activities for elementary school students. This summer issue focuses on the topic of lake life. The issue includes the following features: (1) "Where the Lakes Are Map"; (2) "Letter from the Lake"; (3) "Lake People"; (4)…

  17. Increased piscivory by lake whitefish in Lake Huron

    USGS Publications Warehouse

    Pothoven, Steven A.; Madenjian, Charles P.

    2013-01-01

    We evaluated the diet of Lake Whitefish Coregonus clupeaformis in Lake Huron during 2002–2011 to determine the importance of Round Goby Neogobius melanostomus and other fish as prey items. Lake Whitefish that had reached approximately 400 mm in length incorporated fish into their diets. The overall percentage of adult Lake Whitefish in Lake Huron that had eaten fish increased from 10% in 2002–2006 to 20% in 2007–2011, with a corresponding decrease in the frequency of Lake Whitefish that ate Dreissena spp. from 52% to 33%. During 2002–2006, Round Goby (wet mass, 38%), sculpins (Cottidae) (34%), and Ninespine Stickleback Pungitius pungitius (18%) were the primary fish eaten, whereas Round Goby accounted for 92% of the fish eaten in 2007–2011. Overall, Round Goby were found in the fewest Lake Whitefish stomachs in the north region of Lake Huron (6%) and in the most in the central (23%) and south (19%) regions of the lake. In the central region, Round Goby were eaten during all seasons that were sampled (spring through fall). In the south region, Round Goby were eaten only in the winter and spring but not in the summer when Dreissena spp. and spiny water flea Bythotrephes longimanus dominated the diet. Based on the 2007–2011 diet composition, an individual Lake Whitefish would need to have increased their consumption relative to that in 1983–1994 by 6% in the north region, 12% in the central region, and 41% in the southern region in order to achieve the same growth that was observed before dreissenid mussels arrived. However, Lake Whitefish weight adjusted for length only increased by 2% between 2002–2006 and 2007–2011 in the central region, decreased by 4% in the northern region, and remained constant in the southern region. This suggests that a shift toward more frequent piscivory does not necessarily improve the condition of a generalist feeder like Lake Whitefish.

  18. Holocene lake-level fluctuations of Lake Aricota, Southern Peru

    USGS Publications Warehouse

    Placzek, C.; Quade, Jay; Betancourt, J.L.

    2001-01-01

    Lacustrine deposits exposed around Lake Aricota, Peru (17?? 22???S), a 7.5-km2 lake dammed by debris flows, provide a middle to late Holocene record of lake-level fluctuations. Chronological context for shoreline deposits was obtained from radiocarbon dating of vascular plant remains and other datable material with minimal 14C reservoir effects (<350 yr). Diatomites associated with highstands several meters above the modern lake level indicate wet episodes. Maximum Holocene lake level was attained before 6100 14C yr B.P. and ended ???2700 14C yr B.P. Moderately high lake levels occurred at 1700 and 1300 14C yr B.P. The highstand at Lake Aricota during the middle Holocene is coeval with a major lowstand at Lake Titicaca (16?? S), which is only 130 km to the northeast and shares a similar climatology. Comparisons with other marine and terrestrial records highlight emerging contradictions over the nature of mid-Holocene climate in the central Andes. ?? 2001 University of Washington.

  19. Holocene Lake-Level Fluctuations of Lake Aricota, Southern Peru

    NASA Astrophysics Data System (ADS)

    Placzek, Christa; Quade, Jay; Betancourt, Julio L.

    2001-09-01

    Lacustrine deposits exposed around Lake Aricota, Peru (17° 22‧S), a 7.5-km2 lake dammed by debris flows, provide a middle to late Holocene record of lake-level fluctuations. Chronological context for shoreline deposits was obtained from radiocarbon dating of vascular plant remains and other datable material with minimal 14C reservoir effects (<350 yr). Diatomites associated with highstands several meters above the modern lake level indicate wet episodes. Maximum Holocene lake level was attained before 6100 14C yr B.P. and ended ∼2700 14C yr B.P. Moderately high lake levels occurred at 1700 and 1300 14C yr B.P. The highstand at Lake Aricota during the middle Holocene is coeval with a major lowstand at Lake Titicaca (16°S), which is only 130 km to the northeast and shares a similar climatology. Comparisons with other marine and terrestrial records highlight emerging contradictions over the nature of mid-Holocene climate in the central Andes.

  20. Reevaluation of lake trout and lake whitefish bioenergetics models

    USGS Publications Warehouse

    Madenjian, Charles P.; Pothoven, Steve A.; Kao, Yu-Chun

    2013-01-01

    Using a corrected algorithm for balancing the energy budget, we reevaluated the Wisconsin bioenergetics model for lake trout (Salvelinus namaycush) in the laboratory and for lake whitefish (Coregonus clupeaformis) in the laboratory and in the field. For lake trout, results showed that the bioenergetics model slightly overestimated food consumption by the lake trout when they were fed low and intermediate rations, whereas the model predicted food consumption by lake trout fed ad libitum without any detectable bias. The slight bias in model predictions for lake trout on restricted rations may have been an artifact of the feeding schedule for these fish, and we would therefore recommend application of the Wisconsin lake trout bioenergetics model to lake trout populations in the field without any revisions to the model. Use of the Wisconsin bioenergetics model for coregonids resulted in overestimation of food consumption by lake whitefish both in the laboratory and in the field by between 20 and 30%, on average. This overestimation of food consumption was most likely due to overestimation of respiration rate. We therefore adjusted the respiration component of the bioenergetics model to obtain a good fit to the observed consumption in our laboratory tanks. The adjusted model predicted the consumption in the laboratory and the field without any detectable bias. Until a detailed lake whitefish respiration study can be conducted, we recommend application of our adjusted version of the Wisconsin generalized coregonid bioenergetics model to lake whitefish populations in the field.

  1. Late Holocene lake-level fluctuations in Walker Lake, Nevada, USA

    USGS Publications Warehouse

    Yuan, F.; Linsley, B.K.; Howe, S.S.; Lund, S.P.; McGeehin, J.P.

    2006-01-01

    Walker Lake, a hydrologically closed, saline, and alkaline lake, is situated along the western margin of the Great Basin in Nevada of the western United States. Analyses of the magnetic susceptibility (??), total inorganic carbon (TIC), and oxygen isotopic composition (??18O) of carbonate sediments including ostracode shells (Limnocythere ceriotuberosa) from Walker Lake allow us to extend the sediment record of lake-level fluctuations back to 2700??years B.P. There are approximately five major stages over the course of the late Holocene hydrologic evolution in Walker Lake: an early lowstand (> 2400??years B.P.), a lake-filling period (??? 2400 to ??? 1000??years B.P.), a lake-level lowering period during the Medieval Warm Period (MWP) (??? 1000 to ??? 600??years B.P.), a relatively wet period (??? 600 to ??? 100??years B.P.), and the anthropogenically induced lake-level lowering period (< 100??years B.P.). The most pronounced lowstand of Walker Lake occurred at ??? 2400??years B.P., as indicated by the relatively high values of ??18O. This is generally in agreement with the previous lower resolution paleoclimate results from Walker Lake, but contrasts with the sediment records from adjacent Pyramid Lake and Siesta Lake. The pronounced lowstand suggests that the Walker River that fills Walker Lake may have partially diverted into the Carson Sink through the Adrian paleochannel between 2700 to 1400??years B.P. ?? 2006 Elsevier B.V. All rights reserved.

  2. Bathythermal habitat use by strains of Great Lakes- and Finger Lakes-origin lake trout in Lake Huron after a change in prey fish abundance and composition

    USGS Publications Warehouse

    Bergstedt, Roger A.; Argyle, Ray L.; Krueger, Charles C.; Taylor, William W.

    2012-01-01

    A study conducted in Lake Huron during October 1998–June 2001 found that strains of Great Lakes-origin (GLO) lake trout Salvelinus namaycush occupied significantly higher temperatures than did Finger Lakes-origin (FLO; New York) lake trout based on data from archival (or data storage) telemetry tags that recorded only temperature. During 2002 and 2003, we implanted archival tags that recorded depth as well as temperature in GLO and FLO lake trout in Lake Huron. Data subsequently recorded by those tags spanned 2002–2005. Based on those data, we examined whether temperatures and depths occupied by GLO and FLO lake trout differed during 2002–2005. Temperatures occupied during those years were also compared with occupied temperatures reported for 1998–2001, before a substantial decline in prey fish biomass. Temperatures occupied by GLO lake trout were again significantly higher than those occupied by FLO lake trout. This result supports the conclusion of the previous study. The GLO lake trout also occupied significantly shallower depths than FLO lake trout. In 2002–2005, both GLO and FLO lake trout occupied significantly lower temperatures than they did in 1998–2001. Aside from the sharp decline in prey fish biomass between study periods, the formerly abundant pelagic alewife Alosa pseudoharengus virtually disappeared and the demersal round goby Neogobius melanostomus invaded the lake and became locally abundant. The lower temperatures occupied by lake trout in Lake Huron during 2002–2005 may be attributable to changes in the composition of the prey fish community, food scarcity (i.e., a retreat to cooler water could increase conversion efficiency), or both.

  3. Chemours Pompton Lakes Works Site, Pompton Lakes, NJ

    EPA Pesticide Factsheets

    E.I. DuPont De Nemours & Company is located at 2000 Cannonball Road, Pompton Lakes, New Jersey. The DuPont Pompton Lakes Works site (DuPont) occupies approximately 570 acres of land in Pompton Lakes and Wanaque.

  4. Porewater salinity reveals past lake-level changes in Lake Van, the Earth's largest soda lake.

    PubMed

    Tomonaga, Yama; Brennwald, Matthias S; Livingstone, David M; Kwiecien, Olga; Randlett, Marie-Ève; Stockhecke, Mona; Unwin, Katie; Anselmetti, Flavio S; Beer, Jürg; Haug, Gerald H; Schubert, Carsten J; Sturm, Mike; Kipfer, Rolf

    2017-03-22

    In closed-basin lakes, sediment porewater salinity can potentially be used as a conservative tracer to reconstruct past fluctuations in lake level. However, until now, porewater salinity profiles did not allow quantitative estimates of past lake-level changes because, in contrast to the oceans, significant salinity changes (e.g., local concentration minima and maxima) had never been observed in lacustrine sediments. Here we show that the salinity measured in the sediment pore water of Lake Van (Turkey) allows straightforward reconstruction of two major transgressions and a major regression that occurred during the last 250 ka. We observed strong changes in the vertical salinity profiles of the pore water of the uppermost 100 m of the sediments in Lake Van. As the salinity balance of Lake Van is almost at steady-state, these salinity changes indicate major lake-level changes in the past. In line with previous studies on lake terraces and with seismic and sedimentological surveys, we identify two major transgressions of up to +105 m with respect to the current lake level at about 135 ka BP and 248 ka BP starting at the onset of the two previous interglacials (MIS5e and MIS7), and a major regression of about -200 m at about 30 ka BP during the last ice age.

  5. 15-year incidence of diabetic ketoacidosis at onset of type 1 diabetes in children from a regional setting (Auckland, New Zealand).

    PubMed

    Jefferies, Craig; Cutfield, Samuel W; Derraik, José G B; Bhagvandas, Jignal; Albert, Benjamin B; Hofman, Paul L; Gunn, Alistair J; Cutfield, Wayne S

    2015-05-19

    We assessed the incidence of diabetic ketoacidosis (DKA) in children aged <15 years with newly diagnosed type 1 diabetes mellitus (T1DM) in the Auckland Region (New Zealand) in 1999-2013, in a retrospective review of a complete regional cohort. DKA and its severity were classified according to ISPAD 2014 guidelines. Of 730 children presenting with new-onset T1DM over the 15-year time period, 195 cases had DKA of any severity (27%). There was no change in the incidence of DKA or the proportion of children with severe DKA at presentation. The incidence of DKA among children aged <2.0 years (n = 40) was 53% compared to 25% for those aged 2-14 years (n = 690; p = 0.005). In children aged 2-14 years, increasing age at diagnosis was associated with greater likelihood of DKA at presentation (p = 0.025), with the odds of DKA increasing 1.06 times with each year increase in age. Non-Europeans were more likely to present in DKA than New Zealand Europeans (OR 1.52; p = 0.048). Despite a consistent secular trend of increasing incidence of T1DM, there was no reduction in the incidence of DKA in new-onset T1DM in the Auckland Region over time. Thus, it is important to explore ways to reduce DKA risk.

  6. Spatial and temporal genetic diversity of lake whitefish (Coregonus clupeaformis (Mitchill)) from Lake Huron and Lake Erie

    USGS Publications Warehouse

    Stott, Wendylee; Ebener, Mark P.; Mohr, Lloyd; Hartman, Travis; Johnson, Jim; Roseman, Edward F.

    2013-01-01

    Lake whitefish (Coregonus clupeaformis (Mitchill)) are important commercially, culturally, and ecologically in the Laurentian Great Lakes. Stocks of lake whitefish in the Great Lakes have recovered from low levels of abundance in the 1960s. Reductions in abundance, loss of habitat and environmental degradation can be accompanied by losses of genetic diversity and overall fitness that may persist even as populations recover demographically. Therefore, it is important to be able to identify stocks that have reduced levels of genetic diversity. In this study, we investigated patterns of genetic diversity at microsatellite DNA loci in lake whitefish collected between 1927 and 1929 (historical period) and between 1997 and 2005 (contemporary period) from Lake Huron and Lake Erie. Genetic analysis of lake whitefish from Lakes Huron and Erie shows that the amount of population structuring varies from lake to lake. Greater genetic divergences among collections from Lake Huron may be the result of sampling scale, migration patterns and demographic processes. Fluctuations in abundance of lake whitefish populations may have resulted in periods of increased genetic drift that have resulted in changes in allele frequencies over time, but periodic genetic drift was not severe enough to result in a significant loss of genetic diversity. Migration among stocks may have decreased levels of genetic differentiation while not completely obscuring stock boundaries. Recent changes in spatial boundaries to stocks, the number of stocks and life history characteristics of stocks further demonstrate the potential of coregonids for a swift and varied response to environmental change and emphasise the importance of incorporating both spatial and temporal considerations into management plans to ensure that diversity is preserved.

  7. Cold, dry air is associated with influenza and pneumonia mortality in Auckland, New Zealand.

    PubMed

    Davis, Robert E; Dougherty, Erin; McArthur, Colin; Huang, Qiu Sue; Baker, Michael G

    2016-07-01

    The relationship between weather and influenza and pneumonia mortality was examined retrospectively using daily data from 1980 to 2009 in Auckland, New Zealand, a humid, subtropical location. Mortality events, defined when mortality exceeded 0·95 standard deviation above the mean, followed periods of anomalously cold air (ta.m. = -4·1, P < 0·01; tp.m. = -4·2, P < 0·01) and/or anomalously dry air (ta.m. = -4·1, P < 0·01; tp.m. = -3·8, P < 0·01) by up to 19 days. These results suggest that respiratory infection is enhanced during unusually cold conditions and during conditions with unusually low humidity, even in a subtropical location where humidity is typically high. © 2015 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  8. Movements of hatchery-reared lake trout in Lake Superior

    USGS Publications Warehouse

    Pycha, Richard L.; Dryer, William R.; King, George R.

    1965-01-01

    The history of stocking of lake trout (Salvelinus namaycush) in the Great Lakes is reviewed. The study of movements is based on capture of 24,275 fin-clipped lake trout taken in experimental gill nets and trawls and commercial gill nets. Yearling lake trout planted from shore dispersed to 15-fath (27-m) depths in 3A? hr. Most fish remained within 2 miles (3.2 km) of the planting site 2 months, but within 4 months some fish had moved as much as 17 miles (27 km). The highest abundance of planted lake trout was in areas 2-4 miles (3.2-6.4 km) from the planting site even 3 years after release. Distance moved and size of fish were not correlated. Dispersal of lake trout begins at planting and probably continues until the fish are mature. Most movement was eastward in southern Lake Superior and followed the counterclockwise surface currents. Movement is most rapid in areas of strong currents and slowest in areas of weak currents or eddies. Movement to areas west of the Keweenaw Peninsula was insignificant from plantings in Keweenaw Bay and nil from other plantings farther east. Lake trout planted in the eastern third of the lake dispersed more randomly than those planted farther west. Few fish moved farther offshore than the 50-fath (91-m) contour. Lake trout planted in Canadian waters made insignificant contributions to populations in US waters.

  9. Movers and stayers: The geography of residential mobility and CVD hospitalisations in Auckland, New Zealand.

    PubMed

    Exeter, Daniel J; Sabel, Clive E; Hanham, Grant; Lee, Arier C; Wells, Susan

    2015-05-01

    The association between area-level disadvantage and health and social outcomes is unequivocal. However, less is known about the health impact of residential mobility, particularly at intra-urban scales. We used an encrypted National Health Index (eNHI) number to link individual-level data recorded in routine national health databases to construct a cohort of 641,532 participants aged 30+ years to investigate the association between moving and CVD hospitalisations in Auckland, New Zealand. Residential mobility was measured for participants according to changes in the census Meshblock of usual residence, obtained from the Primary Health Organisation (PHO) database for every calendar quarter between 1/1/2006 and 31/12/2012. The NZDep2006 area deprivation score at the start and end of a participant's inclusion in the study was used to measure deprivation mobility. We investigated the relative risk of movers being hospitalised for CVD relative to stayers using multi-variable binomial regression models, controlling for age, gender, deprivation and ethnicity. Considered together, movers were 1.22 (1.19-1.26) times more likely than stayers to be hospitalised for CVD. Using the 5×5 deprivation origin-destination matrix to model a patient's risk of CVD based on upward, downward or sideways deprivation mobility, movers within the least deprived (NZDep2006 Quintile 1) areas were 10% less likely than stayers to be hospitalised for CVD, while movers within the most deprived (NZDep2006 Q5) areas were 45% more likely than stayers to have had their first CVD hospitalisation in 2006-2012 (RR: 1.45 [1.35-1.55]). Participants who moved upward also had higher relative risks of having a CVD event, although their risk was less than those observed for participants experiencing downward deprivation mobility. This research suggests that residential mobility is an important determinant of CVD in Auckland. Further investigation is required to determine the impact moving has on the risk of

  10. Improved survival after stroke: is admission to hospital the major explanation? Trend analyses of the Auckland Regional Community Stroke Studies.

    PubMed

    Carter, Kristie N; Anderson, Craig S; Hackett, Maree L; Barber, P Alan; Bonita, Ruth

    2007-01-01

    There is uncertainty regarding the impact of changes in stroke care and natural history of stroke in the community. We examined factors responsible for trends in survival after stroke in a series of population-based studies. We used statistical models to assess temporal trends in 28-day and 1-year case fatality after first-ever stroke cases registered in 3 stroke incidence studies undertaken in Auckland, New Zealand, over uniform 12-month calendar periods in 1981-1982 (n = 1,030), 1991-1992 (1,305) and 2001-2002 (1,423). Cox proportional hazards regression was used to evaluate the significance of pre-defined 'patient', 'disease' and 'service/care' factors on these trends. Overall, there was a 40% decline in 28-day case fatality after stroke over the study periods, from 32% (95% confidence interval, 29-35%) in 1981-1982 to 23% (21-25%) in 1991-1992 and then 19% (17-21%) in 2002-2003. Similar relative declines were seen in 1-year case fatality. In regression models, the trends were still significant after adjusting for patient and disease factors. However, further adjustment for care factors (higher hospital admission and neuroimaging) explained most of the improvement in survival. These data show significant downwards trends in case fatality after stroke in Auckland over 20 years, which can largely be attributed to improved stroke care associated with increases in hospital admission and brain imaging during the acute phase of the illness.

  11. Contribution by primary health nurses and general practitioners to the Diabetes Annual Review (Get Checked) programme in Auckland, New Zealand.

    PubMed

    Daly, Barbara; Kenealy, Timothy; Arroll, Bruce; Sheridan, Nicolette; Scragg, Robert

    2013-08-16

    To describe primary health care (practice and specialist) nurses involvement in the government-funded annual diabetes review 'Get Checked' programme and the division of care between nurses and general practitioners in Auckland, New Zealand. Of the total 911 practice and specialist nurses identified and working in the greater Auckland region, 276 (30%) were randomly selected and invited to undertake a self-administered questionnaire and telephone interview in 2006-8. An 86% response rate was achieved. Over 60% of practice nurses and over half of specialist nurses participate in 'Get Checked' reviews. Of those nurses, 40% of practice and 70% specialist nurses, reported completing over half of the total number of 'Get Checked' reviews at their practice. Of the nurses sampled who work in general practice (n=198), 38% reported that 'nurses mostly complete' the reviews, 45% stated that 'nurses and doctors equally complete' them and 17% reported that only 'doctors' did so. For the nurses who reported that 'nurses and doctors equally complete' the reviews (n=89), most nurses undertake blood pressure measurements (90%), weigh patients (88%), give lifestyle advice (87%), examine patient's feet (73%), and 44% carried out the complete review of the patients they consult. These findings show the 'Get Checked' programme was successful in engaging practice and community-based specialist nurses in the community management of diabetes and has revealed positive relationships between nurses and doctors, extended roles for nurses and the importance of engaging nurses in the design of health care programmes.

  12. Energy density of lake whitefish Coregonus clupeaformis in Lakes Huron and Michigan

    USGS Publications Warehouse

    Pothoven, S.A.; Nalepa, T.F.; Madenjian, C.P.; Rediske, R.R.; Schneeberger, P.J.; He, J.X.

    2006-01-01

    We collected lake whitefish Coregonus clupeaformis off Alpena and Tawas City, Michigan, USA in Lake Huron and off Muskegon, Michigan USA in Lake Michigan during 2002–2004. We determined energy density and percent dry weight for lake whitefish from both lakes and lipid content for Lake Michigan fish. Energy density increased with increasing fish weight up to 800 g, and then remained relatively constant with further increases in fish weight. Energy density, adjusted for weight, was lower in Lake Huron than in Lake Michigan for both small (≤800 g) and large fish (>800 g). Energy density did not differ seasonally for small or large lake whitefish or between adult male and female fish. Energy density was strongly correlated with percent dry weight and percent lipid content. Based on data from commercially caught lake whitefish, body condition was lower in Lake Huron than Lake Michigan during 1981–2003, indicating that the dissimilarity in body condition between the lakes could be long standing. Energy density and lipid content in 2002–2004 in Lake Michigan were lower than data for comparable sized fish collected in 1969–1971. Differences in energy density between lakes were attributed to variation in diet and prey energy content as well as factors that affect feeding rates such as lake whitefish density and prey abundance.

  13. Effects of lake trout refuges on lake whitefish and cisco in the Apostle Islands Region of Lake Superior

    USGS Publications Warehouse

    Zuccarino-Crowe , Chiara M.; Taylor, William W.; Hansen, Michael J.; Seider, Michael J.; Krueger, Charles C.

    2016-01-01

    Lake trout refuges in the Apostle Islands region of Lake Superior are analogous to the concept of marine protected areas. These refuges, established specifically for lake trout (Salvelinus namaycush) and closed to most forms of recreational and commercial fishing, were implicated as one of several management actions leading to successful rehabilitation of Lake Superior lake trout. To investigate the potential significance of Gull Island Shoal and Devils Island Shoal refuges for populations of not only lake trout but also other fish species, relative abundances of lake trout, lake whitefish (Coregonus clupeaformis), and cisco (Coregonus artedi) were compared between areas sampled inside versus outside of refuge boundaries. During 1982–2010, lake trout relative abundance was higher and increased faster inside the refuges, where lake trout fishing was prohibited, than outside the refuges. Over the same period, lake whitefish relative abundance increased faster inside than outside the refuges. Both evaluations provided clear evidence that refuges protected these species. In contrast, trends in relative abundance of cisco, a prey item of lake trout, did not differ significantly between areas inside and outside the refuges. This result did not suggest indirect or cascading refuge effects due to changes in predator levels. Overall, this study highlights the potential of species-specific refuges to benefit other fish species beyond those that were the refuges' original target. Improved understanding of refuge effects on multiple species of Great Lakes fishes can be valuable for developing rationales for refuge establishment and predicting associated fish community-level effects.

  14. Future volcanic lake research: revealing secrets from poorly studied lakes

    NASA Astrophysics Data System (ADS)

    Rouwet, D.; Tassi, F.; Mora-Amador, R. A.

    2012-04-01

    Volcanic lake research boosted after the 1986 Lake Nyos lethal gas burst, a limnic rather than volcanic event. This led to the formation of the IAVCEI-Commission on Volcanic Lakes, which grew out into a multi-disciplinary scientific community since the 1990's. At Lake Nyos, a degassing pipe is functional since 2001, and two additional pipes were added in 2011, aimed to prevent further limnic eruption events. There are between 150 and 200 volcanic lakes on Earth. Some acidic crater lakes topping active magmatic-hydrothermal systems are monitored continuously or discontinuously. Such detailed studies have shown their usefulness in volcanic surveillance (e.g. Ruapehu, Yugama-Kusatsu-Shiran, Poás). Others are "Nyos-type" lakes, with possible gas accumulation in bottom waters and thus potentially hazardous. "Nyos-type" lakes tend to remain stably stratified in tropical and sub-tropical climates (meromictic), leading to long-term gas build-up and thus higher potential risk. In temperate climates, such lakes tend to turn over in winter (monomictic), and thus liberating its gas charge yearly. We line out research strategies for the different types of lakes. We believe a complementary, multi-disciplinary approach (geochemistry, geophysics, limnology, biology, statistics, etc.) will lead to new insights and ideas, which can be the base for future following-up and monitoring. After 25 years of pioneering studies on rather few lakes, the scientific community should be challenged to study the many poorly studied volcanic lakes, in order to better constrain the related hazard, based on probabilistic approaches.

  15. Gas exchange on Mono Lake and Crowley Lake, California

    NASA Technical Reports Server (NTRS)

    Wanninkhof, Rik; Ledwell, James R.; Broecker, Wallace S.

    1987-01-01

    Gas exchange coefficients (k) have been determined for freshwater Crowley Lake and saline Mono Lake through the use of a man-made purposefully injected gas, SF6. The concentration decreased from an initial value of 40 to 4 pmol/L for Mono Lake and from 20 to 1 pmol/L for Crowley lake over a period of 6 wks. Wind-speed (u) records from anemometers on the shore of each lake made it possible to determine the relationship between k and u. The average u and k values for the experiment were identical for the two lakes, despite the large chemical differences. It is estimated that, for the u values observed over Mono Lake from July to December 1984, the exchange of CO2 occurred 2.5 times faster than without chemical enhancement. This is a factor of 4 lower than needed to explain the high invasion rate of C-14 produced by nuclear bomb tests.

  16. Blood pressure prevalences and levels for a multicultural population in Auckland, New Zealand: results from the Diabetes, Heart and Health Survey 2002/2003.

    PubMed

    Gentles, Dudley; Metcalf, Patricia; Dyall, Lorna; Scragg, Robert; Black, Peter; Schaaf, David; Sundborn, Gerhard; Jackson, Rod

    2006-11-17

    To estimate ethnic-specific raised blood pressure (RBP) prevalences, blood pressure levels, and associations of systolic blood pressure (SBP) in the Auckland region. A cross-sectional survey of adults aged between 35-74 years in the Auckland region. There were 1006 Maori, 996 Pacific people (mostly of Samoan, Tongan, Niuean, or Cook Islands origin), and 2021 Others (mainly Europeans). Approximately 1 in 3 Maori and Pacific people had RBP (defined arbitrarily as greater than and equal to 140/90 mmHg or on blood pressure-lowering treatment), compared to 1 in 5 Others. The prevalences of RBP (adjusted for age and gender) were: Maori 37%, Pacific people 38%, and Others 22%. Maori and Pacific people had higher average systolic and diastolic blood pressure levels than Others (adjusted for age and gender). This difference became non-significant when adjusted for body mass index (BMI). SBP was (on average) higher for: male gender, increased age, increased BMI, no tertiary education, high pulse rate, high cholesterol, high triglycerides, those on current blood pressure-lowering medication. SBP was (on average) lower for current cigarette smokers. Average blood pressure levels and the prevalences of RBP were higher in Pacific people and Maori compared to Others. BMI was identified as the major modifiable factor.

  17. Hydro-ecological degradation due to human impacts in the Twin Streams Watershed, Auckland, New Zealand

    NASA Astrophysics Data System (ADS)

    Torrecillas Nunez, C.; Miguel-rodriguez, A.

    2012-12-01

    As a collaborative project between the Faculties of Engineering of the University of Sinaloa, Mexico and the University of Auckland, an inter-disciplinary team researched historical information, monitoring results and modelling completed over the last ten years to establish the cause-effect relationship of development and human impacts in the watershed and recommend strategies to offset them .The research program analyzed the performance of the Twin Streams watershed over time with modelling of floods, hydrological disturbance indicators, analysis of water quality and ecological information, cost / benefit, harbor modelling and contaminant loads. The watershed is located in the west of Auckland and comprises 10,356 hectare: 8.19% ecologically protected area, 29.70% buffer zone, 6.67% peri-urban, 30.98% urban, 16.04% parks, and 8.42% other; average impermeability is 19.1%. Current population is 129,475 (2011) forecast to grow to 212,798 by 2051. The watershed includes 317.5 km of streams that drain to the Waitemata Harbor. The human impact can be traced back to the 1850s when the colonial settlers logged the native forests, dammed streams and altered the channel hydro-ecology resulting in significant erosion, sediment and changes to flows. In the early 1900s native vegetation started to regenerate in the headwaters, while agriculture and horticulture become established in rest of the watershed leading to the use of quite often very harmful pesticides and insecticides, such as DDT which is still detected in current environmental monitoring programs, and more erosion and channel alterations. As land become unproductive in the 1950s it stared to be urbanized, followed by more intensive urban development in the 1990s. Curiously there was no regulatory regime to control land use in the early stages and consequently over 400 houses were built in the floodplains, as well there were no legislation to control environmental impacts until 1991. Consequently today there is a

  18. Lake

    ERIC Educational Resources Information Center

    Wien, Carol Anne

    2008-01-01

    The lake is blue black and deep. It is a glaciated finger lake, clawed out of rock when ice retracted across Nova Scotia in a northerly direction during the last ice age. The lake is narrow, a little over a mile long, and deep, 90 to 190 feet in places according to local lore, off the charts in others. The author loves to swim there, with a sense…

  19. Reconnaissance data on lakes in the Alpine Lakes Wilderness Area, Washington

    USGS Publications Warehouse

    Dethier, David P.; Heller, Paul L.; Safioles, Sally A.

    1979-01-01

    Sixty lakes in the Alpine Lakes Wilderness Area have been sampled from rubber rafts or helicopter to obtain information on their physical setting and on present water-quality conditions. The lakes are located near the crest of the Cascade Range in Chelan and King Counties, Washington. Basic data from these lakes will be useful for planners concerned with lake and wilderness management, and of interest to hikers and other recreationists who use the lakes.

  20. 75 FR 20920 - Safety Zone; Lake Havasu Grand Prix, Lake Havasu, AZ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-22

    ...-AA00 Safety Zone; Lake Havasu Grand Prix, Lake Havasu, AZ AGENCY: Coast Guard, DHS. ACTION: Temporary... of Lake Havasu on the Colorado River in Lake Havasu City, Arizona for the Lake Havasu Grand Prix... established in support of the Lake Havasu Grand Prix, a marine event that includes participating vessels...

  1. Water-Balance Model to Simulate Historical Lake Levels for Lake Merced, California

    NASA Astrophysics Data System (ADS)

    Maley, M. P.; Onsoy, S.; Debroux, J.; Eagon, B.

    2009-12-01

    Lake Merced is a freshwater lake located in southwestern San Francisco, California. In the late 1980s and early 1990s, an extended, severe drought impacted the area that resulted in significant declines in Lake Merced lake levels that raised concerns about the long-term health of the lake. In response to these concerns, the Lake Merced Water Level Restoration Project was developed to evaluate an engineered solution to increase and maintain Lake Merced lake levels. The Lake Merced Lake-Level Model was developed to support the conceptual engineering design to restore lake levels. It is a spreadsheet-based water-balance model that performs monthly water-balance calculations based on the hydrological conceptual model. The model independently calculates each water-balance component based on available climate and hydrological data. The model objective was to develop a practical, rule-based approach for the water balance and to calibrate the model results to measured lake levels. The advantage of a rule-based approach is that once the rules are defined, they enhance the ability to then adapt the model for use in future-case simulations. The model was calibrated to historical lake levels over a 70-year period from 1939 to 2009. Calibrating the model over this long historical range tested the model over a variety of hydrological conditions including wet, normal and dry precipitation years, flood events, and periods of high and low lake levels. The historical lake level range was over 16 feet. The model calibration of historical to simulated lake levels had a residual mean of 0.02 feet and an absolute residual mean of 0.42 feet. More importantly, the model demonstrated the ability to simulate both long-term and short-term trends with a strong correlation of the magnitude for both annual and seasonal fluctuations in lake levels. The calibration results demonstrate an improved conceptual understanding of the key hydrological factors that control lake levels, reduce uncertainty

  2. Insanity and ethnicity in New Zealand: Māori encounters with the Auckland Mental Hospital, 1860-1900.

    PubMed

    Barry, Lorelle; Coleborne, Catharine

    2011-09-01

    This article examines Māori patients at the Auckland Mental Hospital between 1860 and 1900.We argue that the patient case notes reveal 'European' categories in which Māori were situated, and demonstrate the extent to which the authorities at the hospital grappled with their appearance, their language and their culture, all of which were elements of their ethnicity. We argue that the use of institutional case records is highly suggestive of some of the historical meanings of insanity for Māori, including the lack of detailed or sustained collection of information about patients' tribal affiliations, the interest shown in their rights to land in maintenance payment inquiries, the experiences of cultural alienation or mate Māori, and the sad outcomes for Māori.

  3. Exploring children's seasonal play to promote active lifestyles in Auckland, New Zealand.

    PubMed

    Ergler, Christina R; Kearns, Robin; Witten, Karen

    2016-09-01

    Studies of seasonal barriers for outdoor activities seldom view families' play practices as grounded in the everyday experience of the natural elements. This paper brings 20 families' mundane outdoor play experiences in Auckland's temperate climate to the fore. Through drawings and interviews, families residing in both suburban detached houses and central city apartments revealed locally constituted beliefs about appropriate play spaces (e.g. garden, park). While the majority of participants retreated to indoor activities during winter, some children and their parents viewed the outdoors as the only opportunity for 'real fun'. We advocate the importance of a better understanding of children's seasonal outdoor play. In particular, we argue that in order to promote year-round healthy levels of outdoor activities it is necessary to understand variations in societal, neighbourhood and family values attributed to outdoor activities. Further, to develop a more nuanced understanding of the locational complexities of outdoor play it is important to understand the meanings of, and practices associated with, seasonal and weather conditions in different international locations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. White Lake AOC

    EPA Pesticide Factsheets

    White Lake is in Muskegon County along the eastern shore of Lake Michigan. It was named an Area of Concern on the Great Lakes under the Great Lakes Water Quality Agreement of 1987 and delisted in 2014.

  5. Demographics and ocular biometric characteristics of patients undergoing cataract surgery in Auckland, New Zealand.

    PubMed

    Yoon, Jinny J; Misra, Stuti L; McGhee, Charles Nj; Patel, Dipika V

    2016-03-01

    The aim is to investigate ethnic variation, in presentation and biometric parameters, within the population undergoing cataract surgery in Auckland. The design is a retrospective study. Four thousand nine hundred thirty-one eyes of 3524 consecutive patients undergoing cataract surgery in Auckland Public Hospital over 18 months were included in the study. Analysis of preoperative medical records was performed. Age, gender, self-reported ethnicity, keratometry, anterior chamber depth, axial length and intraocular lens (IOL) power data were collected. Māori (4.7%) were under-represented compared with the proportion of Māori attending the eye clinic (5.5%) and in the major patient catchment area (8.2%). People of Māori, Pacific and Indian ethnicities presented at a significantly younger age (66.4, 65.9 and 67.9 years, respectively) than those of Caucasian and Asian ethnicities (76.4 and 71.3 years, respectively, P < 0.001). Advanced cataract was more likely in Pacific peoples and Māori than Caucasians. The mean axial length was longest in Asian eyes (23.83 ± 1.52 mm). The mean anterior chamber depth in the eyes of Pacific peoples (3.20 ± 0.39 mm) was significantly greater than that of Caucasians (3.09 ± 0.42 mm, P = 0.001) and Asians (3.05 ± 0.49 mm, P < 0.001). The mean IOL power in Asian eyes was 19.45D. This was significantly lower than the IOL power required by Caucasian (20.72D, P < 0.001) and Pacific ethnicities (20.61D, P = 0.001). With-the-rule astigmatism was highly prevalent in Māori and Pacific peoples, whereas in all other ethnicities, against-the-rule astigmatism was more common. This study identified significant ethnic variation in presentation for cataract surgery and ocular biometric parameters. These data may help identify potential biometric refinements and those at risk of developing ocular morbidities known to be associated with these parameters. © 2015 Royal Australian and New Zealand

  6. In-lake Modeling Recommendation Report for Lake Champlain TMDL

    EPA Pesticide Factsheets

    This report describes the recommended modeling approach for the in-lake modeling component of the Lake Champlain TMDL project. The report was prepared by Tetra Tech, with input from the Lake Champlain modeling workgroup. (TetraTech, 2012b)

  7. Water quality of Lake Austin and Town Lake, Austin, Texas

    USGS Publications Warehouse

    Andrews, Freeman L.; Wells, Frank C.; Shelby, Wanda J.; McPherson, Emma

    1988-01-01

    Water-quality data collected from Lake Austin and Town Lake, following runoff, generally were not adequate to fully determine the effects of runoff on the lakes. Data collection should not to be limited to fixed-station sampling following runoff, and both lakes need to be sampled simultaneously as soon as possible following significant precipitation.

  8. Bathymetry of Bonnie Doone Lake, Kornbow Lake, Mintz Pond, and Glenville Lake, Cumberland County, North Carolina, 1996-98

    USGS Publications Warehouse

    Giorgino, M.J.; Strain, R.E.

    1999-01-01

    Bathymetric surveys were conducted at four water-supply impoundments of Little Cross Creek in Cumberland County, North Carolina. The surveys were conducted in April 1996 at Mintz Pond and Glenville Lake, and in January 1998 at Bonnie Doone Lake and Kornbow Lake. The resulting bathymetric maps are the first to cover the entire range in depth for these reservoirs and provide a framework for future evaluations of bathymetry and storage capacity. Bathymetric maps were constructed from depth and position data collected at each reservoir. A boat-mounted, research-grade fathometer was used to record water depths with a vertical accuracy of 0.1 foot. At Mintz Pond and Glenville Lake, position was measured by using a wide-band laser tracking system interfaced with a total station survey instrument. This positioning method required multiple land-based control points to be established and was hampered by line-of-sight restrictions between the control points and the boat. At Bonnie Doone Lake and Kornbow Lake, a global positioning system was used to collect differentially corrected location data. This positioning method enabled more rapid data collection, eliminated the need for land-based control points, and provided improved data coverage. Spillway elevations range from 172.8 feet above mean sea level at Bonnie Doone Lake to 113.1 feet at Glenville Lake. Surface area and storage volume were computed for each reservoir and were related to water-surface elevations at 1-foot intervals. The combined surface acreage of the four Little Cross Creek reservoirs at their full-pool elevations is 120.97 acres, consisting of 21.20 acres at Bonnie Doone Lake, 47.09 acres at Kornbow Lake, 15.56 acres at Mintz Pond, and 37.12 acres at Glenville Lake. The four reservoirs have a combined usable storage capacity of 674.91 acre-feet, which is the sum of 127.93 acre-feet in Bonnie Doone Lake, 320.62 acre-feet in Kornbow Lake, 53.25 acre-feet in Mintz Pond, and 173.11 acre-feet in Glenville Lake.

  9. Lake trout in the Great Lakes: Basin-wide stock collapse and binational restoration

    USGS Publications Warehouse

    Hansen, Michael J.; Taylor, William W.; Ferreri, C. Paola

    1999-01-01

    The lake trout (Salvelinus namaycush) was important to the human settlement of each of the Great Lakes, and underwent catastrophic collapses in each lake in the nineteenth and twentieth centuries. The timing of lake trout stock collapses were different in each lake, as were the causes of the collapses, and have been the subject of much scientific inquiry and debate. The purpose of this chapter is to summarize and review pertinent information relating historical changes in Great Lakes lake trout stocks, binational efforts to restore those stocks, and progress toward stock restoration. This presentation attempts to generalize patterns across the Great Lakes, rather than to focus within each lake. Lake specific analyses have been used to understand lake specific causes and effects, but there is continuing debate about some of these causes and effects. A basinwide review may suggest mechanisms for observed changes that are not evident by lake specific analysis.

  10. GloboLakes: A global observatory of lake responses to environmental change.

    NASA Astrophysics Data System (ADS)

    Groom, Steve; Tyler, Andrew; Hunter, Peter; Spyrakos, Evangelos; Martinez-Vicente, Victor; Merchant, Chris; Cutler, Mark; Rowan, John; Dawson, Terry; Maberly, Stephen; Cavalho, Laurence; Elliot, Alex; Thackery, Stephen; Miller, Claire; Scott, Marian

    2014-05-01

    The world's freshwater ecosystems are vital components of the global biosphere, yet are vulnerable to climate and other human-induced change. There is increasing recognition that lakes play an important role in global biogeochemical cycling and provide key ecosystem services. However, our understanding of how lakes respond to environmental change at a global scale, and how this impacts on their status and function, is hampered by limited information on their chemical, physical and ecological condition. There are estimated to be over 300 million lakes globally, of which over 17,000 are greater than 10 km2 in surface area. These numbers have limited the systematic study of lake ecosystems. GloboLakes is a five-year UK research programme investigating the state of lakes and their response to climatic and other environmental drivers of change. It will establish a satellite-based observatory with archive and near-real time data processing to produce a time series of observed biogeochemical parameters and lake temperature for over 1000 lakes globally. This will be supported by linked ancillary data on climate and catchment land-use. The ability to monitor a large number of lakes consistently at high frequency and globally will facilitate a paradigm shift in our understanding of how lakes respond to environmental change at different spatial and temporal scales. A key requirement is to validate satellite retrieval algorithms and test the time-series of resulting lake properties such as chlorophyll-a by comparison with in situ data. To support the former extensive bio-optical and constituent data were taken in year 1 of the project in a number of UK lakes with a variety of trophic states. Furthermore, for wider validation activities GloboLakes has established the LIMNADES initiative to create a centralised database of ground bio-optical measurements of worldwide lakes through voluntary cooperation across the international scientific community. This presentation will

  11. The social, cultural and medicinal use of kava for twelve Tongan born men living in Auckland, New Zealand.

    PubMed

    Nosa, Vili; Ofanoa, Malakai

    2009-02-01

    Kava consumption is a very popular practise amongst Pacific people especially amongst the Tongan communities. The purpose of this paper is to identify some of the key cultural, social and medicinal elements of kava use amongst Tongan men. Twelve face to face interviews in this study were undertaken. The paper argues that kava drinking is strongly linked to many of the ceremonial, social and cultural obligations that are deeply embedded within the Tongan culture. The positive uses of kava include medicinal purposes, male bonding, alternative to alcohol consumption, reaffirming and establishing relationships amongst other Tongan men, The men also stated negative uses of kava such as it made them lazy, tired so they were not able to go to work, a lack of sexual activities by being too tired have sex with their partners, and very expensive to buy in New Zealand. The aim of this paper is to discuss and examine the social, cultural and medicinal kava use amongst twelve Tongan born men living in Auckland, New Zealand. The study used qualitative methods, specifically individual interviews were conducted in Tongan or English. Participants were recruited through community networks in Auckland. A number of Tongan churches, Tongan medical clinics such as Langimailie, and kava clubs were approached to recruit participants. The open ended interview schedule covered themes such as access, quantity, frequency, and problems associated with kava use. The interviews were conducted by a Tongan researcher either in English or Tongan. All interviews were translated and transcribed into English. A thematic analysis based on multiple readings of the transcripts was used The analysis identified commonalities and differences. The study was granted ethical approval by the University of Auckland Human Subjects Ethics Committee in December 2004. Interviews were conducted at the beginning of 2005. Interviews were undertaken in a place where the participants felt comfortable. Interview times

  12. 15-year incidence of diabetic ketoacidosis at onset of type 1 diabetes in children from a regional setting (Auckland, New Zealand)

    PubMed Central

    Jefferies, Craig; Cutfield, Samuel W.; Derraik, José G. B.; Bhagvandas, Jignal; Albert, Benjamin B.; Hofman, Paul L.; Gunn, Alistair J.; Cutfield, Wayne S.

    2015-01-01

    We assessed the incidence of diabetic ketoacidosis (DKA) in children aged <15 years with newly diagnosed type 1 diabetes mellitus (T1DM) in the Auckland Region (New Zealand) in 1999–2013, in a retrospective review of a complete regional cohort. DKA and its severity were classified according to ISPAD 2014 guidelines. Of 730 children presenting with new-onset T1DM over the 15-year time period, 195 cases had DKA of any severity (27%). There was no change in the incidence of DKA or the proportion of children with severe DKA at presentation. The incidence of DKA among children aged <2.0 years (n = 40) was 53% compared to 25% for those aged 2–14 years (n = 690; p = 0.005). In children aged 2–14 years, increasing age at diagnosis was associated with greater likelihood of DKA at presentation (p = 0.025), with the odds of DKA increasing 1.06 times with each year increase in age. Non-Europeans were more likely to present in DKA than New Zealand Europeans (OR 1.52; p = 0.048). Despite a consistent secular trend of increasing incidence of T1DM, there was no reduction in the incidence of DKA in new-onset T1DM in the Auckland Region over time. Thus, it is important to explore ways to reduce DKA risk. PMID:25989414

  13. Plasmid-mediated AmpC beta-lactamase-producing Escherichia coli causing urinary tract infection in the Auckland community likely to be resistant to commonly prescribed antimicrobials.

    PubMed

    Drinkovic, Dragana; Morris, Arthur J; Dyet, Kristin; Bakker, Sarah; Heffernan, Helen

    2015-03-13

    To estimate the prevalence and characterise plasmid-mediated AmpC beta-lactamase (PMACBL)- producing Escherichia coli in the Auckland community. All cefoxitin non-susceptible (NS) E. coli identified at the two Auckland community laboratories between 1 January and 31 August 2011 were referred to ESR for boronic acid double-disc synergy testing, to detect the production of AmpC beta-lactamase, and polymerase chain reaction (PCR) to identify the presence of PMACBL genes. PMACBL-producing isolates were typed using pulsed-field gel electrophoresis (PFGE), and PCR was used to determine their phylogenetic group and to identify multilocus sequence type (ST)131. Antimicrobial susceptibility testing and detection of extended-spectrum beta-lactamases (ESBLs) were performed according to the Clinical and Laboratory Standards Institute recommendations. 101 (51%) and 74 (37%) of 200 non-duplicate cefoxitin-NS E. coli were PMACBL producers or assumed hyper-producers of chromosomal AmpC beta-lactamase, respectively. The prevalence of PMACBL-producing E. coli was 0.4%. PMACBL-producing E. coli were significantly less susceptible to norfloxacin, trimethoprim and nitrofurantoin than E. coli that produced neither a PMACBL nor an ESBL. Very few (4%) PMACBL-producing E. coli co-produced an ESBL. Most (88%) of the PMACBL-producing isolates had a CMY-2-like PMACBL. The PMACBL-producing E. coli isolates were diverse based on their PFGE profiles, 44% belonged to phylogenetic group D, and only four were ST131. 100 of the 101 PMACBL-producing E. coli were cultured from urine, and were causing urinary tract infection (UTI) in the majority of patients. The median patient age was 56 years and most (94%) of the patients were women. A greater proportion of patients with community-acquired UTI caused by PMACBL-producing E. coli received a beta-lactam antimicrobial than patients with community-acquired UTI caused by other non-AmpC, non-ESBL-producing E. coli. Thirty-six (43%) patients with community

  14. Dark shadow of the long white cloud: Neighborhood safety is associated with self-rated health and cortisol during pregnancy in Auckland, Aotearoa/New Zealand.

    PubMed

    Thayer, Zaneta M

    2017-12-01

    Auckland, Aotearoa /New Zealand is a culturally and ethnically diverse city. Despite popular global conceptions regarding its utopian nature, the lived experience for many individuals in Auckland attests to the substantial social, economic, and health inequalities that exist there. In particular, rapidly rising home prices constrain housing decisions and force individuals to live in less desirable neighborhoods, with potential impacts on individual health. One of the pathways through which adverse neighborhood conditions could impact health is through alterations in the functioning of the hypothalamic pituitary adrenal (HPA)-axis, which regulates the physiological stress response. This paper evaluates the relationship between perceived neighborhood safety, self-rated health, and cortisol, an end product of HPA-axis activation, among women in late pregnancy. Pregnant women living in neighborhoods where they were concerned about safety of their property had poorer self-rated health and elevated morning cortisol, even after adjusting for maternal age, material deprivation, and ethnicity. However, fear of personal safety was unrelated to self-rated health and cortisol. These results suggest that maternal health in pregnancy is sensitive to perceptions regarding neighborhood safety. Such findings are important since higher cortisol levels in pregnancy could not only influence maternal health, but also the health and development of women's children.

  15. Watershed vs. within-lake drivers of nitrogen: phosphorus dynamics in shallow lakes.

    PubMed

    Ginger, Luke J; Zimmer, Kyle D; Herwig, Brian R; Hanson, Mark A; Hobbs, William O; Small, Gaston E; Cotner, James B

    2017-10-01

    Research on lake eutrophication often identifies variables affecting amounts of phosphorus (P) and nitrogen (N) in lakes, but understanding factors influencing N:P ratios is important given its influence on species composition and toxin production by cyanobacteria. We sampled 80 shallow lakes in Minnesota (USA) for three years to assess effects of watershed size, proportion of watershed as both row crop and natural area, fish biomass, and lake alternative state (turbid vs. clear) on total N : total P (TN : TP), ammonium, total dissolved phosphorus (TDP), and seston stoichiometry. We also examined N:P stoichiometry in 20 additional lakes that shifted states during the study. Last, we assessed the importance of denitrification by measuring denitrification rates in sediment cores from a subset of 34 lakes, and by measuring seston δ 15 N in four additional experimental lakes before and after they were experimentally manipulated from turbid to clear states. Results showed alternative state had the largest influence on overall N:P stoichiometry in these systems, as it had the strongest relationship with TN : TP, seston C:N:P, ammonium, and TDP. Turbid lakes had higher N at given levels of P than clear lakes, with TN and ammonium 2-fold and 1.4-fold higher in turbid lakes, respectively. In lakes that shifted states, TN was 3-fold higher in turbid lakes, while TP was only 2-fold higher, supporting the notion N is more responsive to state shifts than is P. Seston δ 15 N increased after lakes shifted to clear states, suggesting higher denitrification rates may be important for reducing N levels in clear states, and potential denitrification rates in sediment cores were among the highest recorded in the literature. Overall, our results indicate lake state was a primary driver of N:P dynamics in shallow lakes, and lakes in clear states had much lower N at a given level of P relative to turbid lakes, likely due to higher denitrification rates. Shallow lakes are often

  16. Changes in Rongbuk lake and Imja lake in the Everest region of Himalaya

    NASA Astrophysics Data System (ADS)

    Chen, W.; Doko, T.; Liu, C.; Ichinose, T.; Fukui, H.; Feng, Q.; Gou, P.

    2014-12-01

    The Himalaya holds the world record in terms of range and elevation. It is one of the most extensively glacierized regions in the world except the Polar Regions. The Himalaya is a region sensitive to climate change. Changes in the glacial regime are indicators of global climate changes. Since the second half of the last century, most Himalayan glaciers have melted due to climate change. These changes directly affected the changes of glacial lakes in the Himalayan region due to the glacier retreat. New glacial lakes are formed, and a number of them have expanded in the Everest region of the Himalayas. This paper focuses on the two glacial lakes which are Imja Lake, located at the southern slope, and Rongbuk Lake, located at the northern slope in the Mt. Everest region, Himalaya to present the spatio-temporal changes from 1976 to 2008. Topographical conditions between two lakes were different (Kruskal-Wallis test, p < 0.05). Rongbuk Lake was located at 623 m higher than Imja Lake, and radiation of Rongbuk Lake was higher than the Imja Lake. Although size of Imja Lake was larger than the Rongbuk Lake in 2008, the growth speed of Rongbuk Lake was accelerating since 2000 and exceeds Imja Lake in 2000-2008. This trend of expansion of Rongbuk Lake is anticipated to be continued in the 21st century. Rongbuk Lake would be the biggest potential risk of glacial lake outburst flood (GLOF) at the Everest region of Himalaya in the future.

  17. 78 FR 17097 - Safety Zone; Lake Havasu Triathlon; Lake Havasu City, AZ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-20

    ...-AA00 Safety Zone; Lake Havasu Triathlon; Lake Havasu City, AZ AGENCY: Coast Guard, DHS. ACTION... waters of Lake Havasu and the London Bridge Channel for the Lake Havasu Triathlon. This temporary safety... participants. The waterside swim course consists of 1500 meters in Lake Havasu and the London Bridge Channel...

  18. Rangitoto Volcano Drilling Project: Life of a Small 'Monogenetic' Basaltic Shield in the Auckland Volcanic Field

    NASA Astrophysics Data System (ADS)

    Shane, P. A. R.; Linnell, T.; Lindsay, J. M.; Smith, I. E.; Augustinus, P. M.; Cronin, S. J.

    2014-12-01

    Rangitoto is a small basaltic shield volcano representing the most recent and most voluminous episode of volcanism in the Auckland Volcanic Field, New Zealand. Auckland City is built on the field, and hence, Rangitoto's importance in hazard-risk modelling. The symmetrical edifice, ~6 km wide and 260 m high, has volume of 1.78 km3. It comprises summit scoria cones and a lava field. However, the lack of deep erosion dissection has prevented the development of an eruptive stratigraphy. Previous studies suggested construction in a relatively short interval at 550-500 yrs BP. However, microscopic tephra have been interpreted as evidence of intermittent activity from 1498 +/- 140 to 504 +/- 6 yrs BP, a longevity of 1000 years. A 150-m-deep hole was drilled through the edifice in February 2014 to obtain a continuous core record. The result is an unparalleled stratigraphy of the evolution of a small shield volcano. The upper 128 m of core comprises at least 27 lava flows with thicknesses in the range 0.3-15 m, representing the main shield-building phase. Underlying marine sediments are interbedded with 8 m of pyroclastic lapilli, and a thin lava flow, representing the explosive phreatomagmatic birth of the volcano. Preliminary geochemical analyses reveal suite of relatively uniform transitional basalts (MgO = 8.1 to 9.7 wt %). However, 4 compositional groups are distinguished that were erupted in sequential order. High-MgO magmas were erupted first, followed by a two more heterogeneous groups displaying differentiation trends with time. Finally, distinct low-MgO basalts were erupted. Each magma type appears to represent a new magma batch. The core places the magma types in a time series, which can be correlated to the surface lava field. Hence, allowing a geometrical reconstruction of the shield growth. Additional petrologic investigations are providing insight to magmatic ascent processes, while radiocarbon and paleomagnetic secular variation studies will reveal the

  19. Enamel defects and dental caries in 9-year-old children living in fluoridated and nonfluoridated areas of Auckland, New Zealand.

    PubMed

    Kanagaratnam, Sathananthan; Schluter, Philip; Durward, Callum; Mahood, Robyn; Mackay, Tim

    2009-06-01

    This epidemiological study aims to investigate the developmental enamel defects and dental caries among 9-year-old children resident in fluoridated and nonfluoridated regions in Auckland, New Zealand. A stratified, two-stage random selection design where strata were defined by fluoridation status, school size, and school decile. After informed consent was obtained, parents completed oral health questionnaires and children underwent dental examinations at school clinics. 612 children from 38 schools participated in the study. Overall, 175 (29%) children had lived continuously in fluoridated areas, 149 (24%) had lived continuously in nonfluoridated areas, and 288 (47%) had resided intermittently in fluoridated areas. Diffuse opacities were present in 117 (19%) children and deciduous teeth dental caries was seen in 370 (60%) children. After adjustment for covariates, a strong dose-response relationship between diffuse opacity and fluoridation status was found, with children who lived continuously in fluoridated areas being 4.17 times as likely to have diffuse opacities as children who lived continuously in nonfluoridated areas (P < 0.001). Conversely, a strong protective dose-response relationship between caries experience and fluoridation status was seen, with children who lived continuously in fluoridated areas being 0.42 times as likely to have dental caries as children who lived continuously in nonfluoridated areas (P < 0.001). Reticulated water fluoridation in Auckland reduces the risk of dental caries but increases the risk of diffuse opacities in 9-year-old children. Guidelines and health-promotion strategies that enable children to minimize their risk to diffuse opacities yet reduce their risk of dental caries should be reviewed.

  20. The age of permanent tooth emergence in children of different ethnic origin in the Auckland region: a cross-sectional study.

    PubMed

    Kanagaratnam, Sathananthan; Schluter, Philip J

    2012-06-01

    To report robust and contemporary estimates of permanent teeth emergence ages in children of Māori, Pasifika, Chinese, Indian and European ethnic origin in the Auckland region. A stratified, two-stage cross-sectional study. Strata were defined by school decile status. Schools defined the first-stage sampling unit, and students the second stage. Invitations and consent forms were distributed to eligible participants at school for completion at home. Participants were examined at school-based clinics or in a mobile clinic. PARTICIPANTS/MATERIALS, AND METHODS: Children aged between 5 and 13 years enrolled within the Auckland Regional Dental Service. Schools were randomly selected and then all students within selected schools were invited to participate. Eligible participants completing a consent form had an additional tooth assessment that complemented their routine dental examination. A generalised gamma failure-time model was employed to estimate permanent tooth eruption ages. Visually based assessment of permanent tooth emergence. Overall, 3,466 children participated. Differences in median permanent tooth emergence ages were seen among ethnic groups and sexes (P < or = 0.01). Pasifika children had earlier median eruption time than sex-matched Māori children, who (in turn) were more advanced than sex-matched European children. Median eruption age occurred earlier in girls than boys for all permanent teeth. Despite known demographic, geographic and ethnic differences, estimates of permanent teeth emergence timing widely used in New Zealand are based on historical overseas populations. The presented estimates provide new standards and may be more appropriate for dental therapists and dentists when assessing permanent teeth emergence in New Zealand children.

  1. Competition between larval lake herring (Coregonus artedi) and lake whitefish (Coregonus clupeaformis) for zooplankton

    USGS Publications Warehouse

    Davis, Bruce M.; Todd, Thomas N.

    1998-01-01

    Diet and growth of larval lake herring (Coregonus artedi) and lake whitefish (Coregonus clupeaformis) were compared in mesocosm experiments in a small mesotrophic lake in southeastern Michigan. Fish were sampled from single-species and mixed assemblages in 2-m3 cages for 8 weeks during April and May. Both species initially ate mostly cyclopoid copepodites and small cladocerans (Bosmia spp.). Schoener's index of diet overlap showed considerable overlap (70-90%). Lake whitefish ate Daphnia spp. and adult copepods about 2 weeks earlier than did lake herring, perhaps related to their larger mean mouth gape. Lake whitefish were consistently larger than lake herring until the eighth week, especially in the sympatric treatments. Lake whitefish appeared to have a negative effect on the growth of lake herring, as lake herring in mixed-species treatments were smaller and weighed less than lake herring reared in single-species treatments. The diet similarities of lake whitefish and lake herring larvae could make them competitors for food in the Great Lakes. The greater initial size of lake whitefish could allow them to eat larger prey earlier and thereby limit availability of these prey to lake herring at a crucial period of development.

  2. The Morphometry of Lake Palmas, a Deep Natural Lake in Brazil

    PubMed Central

    Barroso, Gilberto F.; Gonçalves, Monica A.; Garcia, Fábio da C.

    2014-01-01

    Lake Palmas (A = 10.3km2) is located in the Lower Doce River Valley (LDRV), on the southeastern coast of Brazil. The Lake District of the LDRV includes 90 lakes, whose basic geomorphology is associated with the alluvial valleys of the Barreiras Formation (Cenozoic, Neogene) and with the Holocene coastal plain. This study aimed to investigate the relationship of morphometry and thermal pattern of a LDRV deep lake, Lake Palmas. A bathymetric survey carried out in 2011 and the analysis of hydrographic and wind data with a geographic information system allowed the calculation of several metrics of lake morphometry. The vertical profiling of physical and chemical variables in the water column during the wet/warm and dry/mild cold seasons of 2011 to 2013 has furnished a better understanding of the influence of the lake morphometry on its structure and function. The overdeepened basin has a subrectangular elongated shape and is aligned in a NW-SE direction in an alluvial valley with a maximum depth (Zmax) of 50.7m, a volume of 2.2×108 m3 (0.22km3) and a mean depth (Zmv) of 21.4m. These metrics suggest Lake Palmas as the deepest natural lake in Brazil. Water column profiling has indicated strong physical and chemical stratification during the wet/warm season, with a hypoxic/anoxic layer occupying one-half of the lake volume. The warm monomictic pattern of Lake Palmas, which is in an accordance to deep tropical lakes, is determined by water column mixing during the dry and mild cold season, especially under the influence of a high effective fetch associated with the incidence of cold fronts. Lake Palmas has a very long theoretical retention time, with a mean of 19.4 years. The changes observed in the hydrological flows of the tributary rivers may disturb the ecological resilience of Lake Palmas. PMID:25406062

  3. Embryotoxicity of Great Lakes lake trout extracts to developing rainbow trout

    USGS Publications Warehouse

    Wright, Peggy J.; Tillitt, Donald E.

    1999-01-01

    Planar halogenated hydrocarbons (PHHs), such as polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls are present in aquatic systems, and are known to produce adverse effects in fish. This study investigated the embryotoxicity of PHH mixtures through the nanoinjection of environmental extracts into newly fertilized eggs from two strains of rainbow trout. Organic extracts were obtained from whole adult lake trout collected from Lake Michigan in 1988 and Lake Superior in 1994. The graded doses of the final extracts used for injection were quantified as 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic-equivalents (TEQs) based on the concentrations of dioxins, furans and non-o-PCBs in each, and as equivalent amounts found in the eggs of the original lake trout (eggEQ). Total TEQs in the lake trout were 14.7 pg TEQ/g in the Lake Michigan sample and 7.3 pg TEQ/g in the Lake Superior sample. The extract of the Lake Michigan lake trout was embryotoxic to rainbow trout; LD50 values were 35 eggEQ (15–90, 95% F.L.) in the Arlee strain and 14 eggEQ (5–99, 95% F.L.) in the Erwin strain of rainbow trout. The LD50 values of the Lake Michigan extract in either of these strains of rainbow trout fall within the actual range of TCDD LD50values based on TEQs. This indicates that an additive model of toxicity is appropriate to quantify PHHs in relation to early life stage mortality in fish. Gross lesions characteristic of exposure to PHHs (i.e. yolk-sac edema, craniofacial deformities, and hemorrhaging) increased in a dose-related manner. The lowest observable adverse effect concentrations (LOAEC) for these gross lesions and cumulative mortalities suggests that current concentrations of PHHs in lake trout from Lake Michigan are above a threshold for adverse effects and these compounds may have implications on the lack of recruitment in certain Great Lakes lake trout populations.

  4. Great Lakes

    NASA Image and Video Library

    2017-12-08

    Bands of lake effect snow drift eastward from the western Great Lakes in this true-color image captured by the NOAA/NASA Suomi NPP satellite's Visible Infrared Imaging Radiometer Suite (VIIRS) instrument on January 5, 2017. National Weather Service forecasters expect light to moderate lake effect snow showers to continue throughout the day today and into Saturday (1/7). Lake-effect snow forms when cold air passes over the warmer waters of a lake. This causes some lake water to evaporate into the air and warm it. This warmer, wetter air rises and cools as it moves away from the lake. When it cools, it releases that moisture and, if it’s cold enough, that moisture turns into snow. Although true-color images like this may appear to be photographs of Earth, they aren't. They are created by combining data from the three color channels on the VIIRS instrument sensitive to the red, green and blue (or RGB) wavelengths of light into one composite image. In addition, data from several other channels are often also included to cancel out or correct atmospheric interference that may blur parts of the image. Credit: NOAA/NASA/Suomi NPP via NOAA's Environmental Visualization Laboratory

  5. Lake Michigan lake trout PCB model forecast post audit

    EPA Science Inventory

    Scenario forecasts for total PCBs in Lake Michigan (LM) lake trout were conducted using the linked LM2-Toxics and LM Food Chain models, supported by a suite of additional LM models. Efforts were conducted under the Lake Michigan Mass Balance Study and the post audit represents th...

  6. Water-quality and lake-stage data for Wisconsin lakes, water year 2005

    USGS Publications Warehouse

    Rose, W.J.; Garn, H.S.; Goddard, G.L.; Marsh, S.B.; Olson, D.L.; Robertson, Dale M.

    2006-01-01

    The U.S. Geological Survey (USGS), in cooperation with local and other agencies, collects data at selected lakes throughout Wisconsin. These data, accumulated over many years, provide a data base for developing an improved understanding of the water quality of lakes. The purpose of this report is to provide information about the chemical and physical charac-teristics of Wisconsin lakes. Data that have been collected at specific lakes, and information to aid in the interpretation of those data, are included in this report. Data collected include measure-ments of in-lake water quality and lake stage. Time series graphs of Secchi depths, surface total phosphorus and chlorophyll a concentrations collected during non-frozen periods are included for all lakes. Graphs of vertical profiles of temperature, dissolved oxygen, pH, and specific conductance are included for sites where these parameters were measured. Descriptive infor-mation for each lake includes: location of the lake, area of the lake's watershed, period for which data are available, revisions to previously published records, and pertinent remarks.

  7. Using Satellite Imagery to Monitor the Major Lakes; Case Study Lake Hamun

    NASA Astrophysics Data System (ADS)

    Norouzi, H.; Islam, R.; Bah, A.; AghaKouchak, A.

    2015-12-01

    Proper lakes function can ease the impact of floods and drought especially in arid and semi-arid regions. They are important environmentally and can directly affect human lives. Better understanding of the effect of climate change and human-driven changes on lakes would provide invaluable information for policy-makers and local people. As part of a comprehensive study, we aim to monitor the land-cover/ land-use changes in the world's major lakes using satellite observations. As a case study, Hamun Lake which is a pluvial Lake, also known as shallow Lake, located on the south-east of Iran and adjacent to Afghanistan, and Pakistan borders is investigated. The Lake is the main source of resources (agriculture, fishing and hunting) for the people around it and politically important in the region since it is shared among three different countries. The purpose of the research is to find the Lake's area from 1972 to 2015 and to see if any drought or water resources management has affected the lake. Analyzing satellites imagery from Landsat shows that the area of the Lake changes seasonally and intra-annually. Significant seasonal effects are found in 1975,1977, 1987, 1993, 1996, 1998, 2000, 2009 and 2011, as well as, substantial amount of shallow water is found throughout the years. The precipitation records as well as drought historical records are studied for the lake's basin. Meteorological studies suggest that the drought, decrease of rainfalls in the province and the improper management of the Lake have caused environmental, economic and geographical consequences. The results reveal that lake has experienced at least two prolong dryings since 1972 which drought cannot solely be blamed as main forcing factor.Proper lakes function can ease the impact of floods and drought especially in arid and semi-arid regions. They are important environmentally and can directly affect human lives. Better understanding of the effect of climate change and human-driven changes on lakes

  8. A coupled lake-atmosphere model (CLAM) and its application to Lake Kinneret

    NASA Astrophysics Data System (ADS)

    Pan, Hai

    1999-08-01

    Kinneret is a 166-km2 lake located in Northern Israel, in the central part of the Jordan Valley, a corridor running from north to south, between the Galilee hills in the west and the Golan Heights in the east. Both the Galilee hills and the Golan Heights reach an elevation of about 400 m above mean sea level (MSL), and the lake is about -210 m (MSL). North of the lake is the mountainous area of the Hermon, culminating at about 2800 m (MSL). About 120 km south of it is the Dead Sea, which is about -410 m (MSL), and about 45 km west of it is the Mediterranean Sea. The complexity of the terrain, combined with relatively arid soil and various ground covers surrounding the lake, results in a very complicated system of atmospheric and lake processes. To understand this system, especially the processes affecting the atmosphere and lake dynamics and thermodynamics, and their effects on Lake Kinneret evaporation, a coupled lake-atmosphere model (CLAM) was developed and applied to the lake region. The CLAM is based on the Regional Atmospheric Modeling System (RAMS) and the oceanic S-coordinate Rutgers University Model (SCRUM). Energy, mass, and momentum are conserved at the interface between the atmosphere and the lake, and appropriate balance equations are applied there. In the atmospheric module, two nested grids are employed to simulate Northern Israel at a resolution of 4 x 4 km2, and the near-lake region at a resolution of 1 x 1 km 2. Synoptic conditions obtained from the National Meteorological Center (NMC) reanalysis are assimilated by the model. Soil moisture, which appears to have a significant impact on atmospheric circulation in this region, was transformed from the normalized difference vegetation index (NDVI). Observations collected during two summers above and inside the lake emphasize the good capability of CLAM to simulate surface fluxes and other microclimatic conditions, as well as lake temperature and currents. Although the lake is small (about 12-km wide

  9. Bathymetric Surveys of Lake Arthur and Raccoon Lake, Pennsylvania, June 2007

    USGS Publications Warehouse

    Hittle, Clinton D.; Ruby, A. Thomas

    2008-01-01

    In spring of 2007, bathymetric surveys of two Pennsylvania State Park lakes were performed to collect accurate data sets of lake-bed elevations and to develop methods and techniques to conduct similar surveys across the state. The lake-bed elevations and associated geographical position data can be merged with land-surface elevations acquired through Light Detection and Ranging (LIDAR) techniques. Lake Arthur in Butler County and Raccoon Lake in Beaver County were selected for this initial data-collection activity. In order to establish accurate water-surface elevations during the surveys, benchmarks referenced to NAVD 88 were established on land at each lake by use of differential global positioning system (DGPS) surveys. Bathymetric data were collected using a single beam, 210 kilohertz (kHz) echo sounder and were coupled with the DGPS position data utilizing a computer software package. Transects of depth data were acquired at predetermined intervals on each lake, and the shoreline was delineated using a laser range finder and compass module. Final X, Y, Z coordinates of the geographic positions and lake-bed elevations were referenced to NAD 83 and NAVD 88 and are available to create bathymetric maps of the lakes.

  10. Knowledge and beliefs about nutrition and physical activity during pregnancy in women from South Auckland region, New Zealand.

    PubMed

    Okesene-Gafa, Karaponi; Chelimo, Carol; Chua, Shireen; Henning, Marcus; McCowan, Lesley

    2016-10-01

    Approximately 60% of women in South Auckland, a culturally diverse region in New Zealand, become pregnant with a high body mass index. However, little is known about these women's knowledge of nutrition and physical activity during pregnancy. To assess knowledge of nutrition and physical activity during pregnancy, factors influencing eating habits and the willingness to participate in a nutritional intervention. A total of 422 women completed the survey in late pregnancy between September and December 2013. Multivariable logistic regression investigated factors associated with infrequent healthy eating, adjusting for ethnicity and gestation at questionnaire completion. Ethnicity of participants was Māori (24.2%), Pacific (40.5%), Asian (12.8%) and European/Others (21.8%). Most (95.0%) reported receiving information about healthy eating while pregnant and 61% reported eating healthy frequently or very frequently. Forty-four point three per cent reported eating more in pregnancy; the commonest reasons were cravings and 'eating for two'. The adjusted odd ratios (aORs) indicated that the self-reported factors associated with infrequent healthy eating in this sample were Māori (aOR 17.66; 95% CI 8.49-36.77) and Pacific ethnicity (aOR 14.54; 95% CI 7.32-28.88); parity ≥3 (aOR 2.09; 95%CI 1.26-3.48); obesity (aOR 2.84; 95% CI 1.35-5.97); unplanned pregnancy (aOR 1.95; 95%CI 1.18-3.22); and eating takeaways ≥3 times/week (aOR 4.46; 95%CI 1.88-10.56). Of women sampled, 83.4% would likely/very likely participate in a nutritional intervention. Self-reported factors associated with infrequent healthy eating in pregnancy were identified in this sample. Our findings will assist development of a nutritional intervention for pregnant women in South Auckland. © 2016 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  11. Comparison of catch and lake trout bycatch in commercial trap nets and gill nets targeting lake whitefish in northern Lake Huron

    USGS Publications Warehouse

    Johnson, James E.; Ebener, Mark P.; Gebhardt, Kenneth; Bergstedt, Roger

    2004-01-01

    We compared seasonal lake whitefish catch rates, lake trout bycatch, and gearinduced lake trout mortality between commercial trap nets and gill nets in north-central Lake Huron. Onboard monitors recorded catches from 260 gill net and 96 trap net lifts from October 1998 through December 1999. Catch rates for lake whitefish were highest in fall for both gear types, reflecting proximity of spawning sites to the study area. Lake whitefish catch rates were also relatively high in spring but low in both gear types in summer. Lake trout were the principal bycatch species in both gears. The lake trout bycatch was lowest in both gear types in fall, highest in gill nets in spring, and highest in trap nets in summer. The ratio of lake trout to legal whitefish (the target species) was highest in summer and lowest in fall in both gear types. The high lake trout ratio in summer was due principally to low catch rates of lake whitefish. All but 3 of 186 live lake trout removed from trap net pots survived for at least two days of observation in laboratory tanks. Therefore, we estimated that post-release survival of trap netted lake trout that had not been entangled in the mesh was 98.4%. In addition, we accounted for stress-induced mortality for lake trout that were live at capture but entangled in the mesh of either gear type. Resulting estimates of lake trout survival were higher in trap nets (87.8%) than in gill nets (39.6%). The number of lake trout killed per lift was highest during summer in trap nets and during spring in gill nets. In trap nets, 85% of dead lake trout were observed to be entangled in the mesh of the pot or tunnels. Survival rates of lake trout in gill nets were higher in our study than reported by others, probably because our nets were hand lifted in a small boat. Our trap net-induced mortality estimates on lake trout were higher than those reported by others because we adjusted our estimates to account for post-release mortality caused by handling and

  12. Necrotizing fasciitis: 11-year retrospective case review in South Auckland.

    PubMed

    Kulasegaran, Suheelan; Cribb, Benjamin; Vandal, Alain C; McBride, Stephen; Holland, David; MacCormick, Andrew D

    2016-10-01

    The aims of this paper were to review our experience with necrotizing fasciitis at Middlemore Hospital and to define the trends in incidence, inpatient mortality and microbiological profile. A computerized search of the electronic medical records was undertaken to identify adult patients with a diagnosis of necrotizing fasciitis between January 2000 and December 2010. A retrospective review of the clinical records was performed. Of the 138 patients with necrotizing fasciitis identified, 129 had their diagnosis confirmed at operation. The mortality at 30 days was 20.3% (95% confidence interval (CI) 13.9%-28.0%). There was a significant reduction in hospital mortality in each successive year of the study period with an odds ratio of 0.84 (95% CI 0.71-0.98, P = 0.03). A pattern of increasing incidence was noted until February 2004 (95% CI September 2002-July 2005). This was followed by a significant decrease in incidence. The empirical antibiotic regime of clindamycin, gentamicin and penicillin provides satisfactory cover against 95% of the causative pathogens. This represents the largest single-centre published case series in New Zealand. Despite concerns of increasing incidence and mortality associated with necrotizing fasciitis in New Zealand, the experience in South Auckland shows a decrease in incidence of necrotizing fasciitis since 2004 and a statistically significant decreasing trend in hospital mortality. © 2015 Royal Australasian College of Surgeons.

  13. Lake levels, streamflow, and surface-water quality in the Devils Lake area, North Dakota

    USGS Publications Warehouse

    Wiche, Gregg J.

    1996-01-01

    The Devils Lake Basin is a 3,810-square-mile (mi2) closed basin (fig. 1) in the Red River of the North Basin. About 3,320 mi2 of the total 3,810 mi2 is tributary to Devils Lake; the remainder is tributary to Stump Lake.Since glaciation, the lake level of Devils Lake has fluctuated from about 1,457 feet (ft) above sea level (asl), the natural spill elevation of the lake to the Sheyenne River, to 1,400 ft asl (Aronow, 1957). Although no documented records of lake levels are available before 1867, Upham (1895, p. 595), on the basis of tree-ring chronology, indicated that the lake level was 1,441 ft asl in 1830. Lake levels were recorded sporadically from 1867 to 1901 when the U.S. Geological Survey established a gaging station on Devils Lake. From 1867 to the present (1996), the lake level has fluctuated between a maximum of 1,438.4 ft asl in 1867 and a minimum of 1,400.9 ft asl in 1940 (fig. 2). On July 31, 1996, the lake level was 1,437.8 ft asl, about 15.2 ft higher than the level recorded in February 1993 and the highest level in about 120 years.Since 1993, the lake level of Devils Lake (fig. 2) has risen rapidly in response to above-normal precipitation from the summer of 1993 to the present, and 30,000 acres of land around the lake have been flooded. The above-normal precipitation also has caused flooding elsewhere in the Devils Lake Basin. State highways near Devils Lake are being raised, and some local roads have been closed because of flooding.In response to the flooding, the Devils Lake Basin Interagency Task Force, comprised of many State and Federal agencies, was formed in 1995 to find and propose intermediate (5 years or less) solutions to reduce the effects of high lake levels. In addition to various planning studies being conducted by Federal agencies, the North Dakota State Water Commission has implemented a project to store water on small tracts of land and in the chain of lakes (Sweetwater Lake, Morrison Lake, Dry Lake, Mikes Lake, Chain Lake

  14. Genetic diversity of Diporeia in the Great Lakes: comparison of Lake Superior to the other Great Lakes

    EPA Science Inventory

    Abundances of Diporeia have dropped drastically in the Great Lakes, except in Lake Superior, where data suggest that population counts actually have risen. Various ecological, environmental, or geographic hypotheses have been proposed to explain the greater abundance of Lake Supe...

  15. Water-quality and lake-stage data for Wisconsin lakes, water year 1996

    USGS Publications Warehouse

    ,

    1997-01-01

    The purpose of this report is to provide information about the physical and chemical characteristics of Wisconsin lakes. Data that have been collected at specific lakes, and information to aid in the interpretation of those data, are included in this report. Data collected includes measurements of lake stage and in-lake water quality. Graphs of Secchi depths, surface totalphosphorus and chlorophyll-a concentrations versus time are included for lakes with two or more years of data. Graphs of vertical profiles of temperature, dissolved oxygen, pH, and specific conductance are included for sites where these parameters were measured. Descriptive information for each lake includes: location of the lake, drainage area of the lake's watershed, period for which data are available, revisions to previously published records, and pertinent remarks. Additional data, such as streamflow and water quality in tributary and outlet streams of some of the lakes, are published in another volume: "Water Resources Data-Wisconsin, 1996."

  16. Delineation of sympatric morphotypes of lake trout in Lake Superior

    USGS Publications Warehouse

    Moore, Seth A.; Bronte, Charles R.

    2001-01-01

    Three morphotypes of lake trout Salvelinus namaycush are recognized in Lake Superior: lean, siscowet, and humper. Absolute morphotype assignment can be difficult. We used a size-free, whole-body morphometric analysis (truss protocol) to determine whether differences in body shape existed among lake trout morphotypes. Our results showed discrimination where traditional morphometric characters and meristic measurements failed to detect differences. Principal components analysis revealed some separation of all three morphotypes based on head and caudal peduncle shape, but it also indicated considerable overlap in score values. Humper lake trout have smaller caudal peduncle widths to head length and depth characters than do lean or siscowet lake trout. Lean lake trout had larger head measures to caudal widths, whereas siscowet had higher caudal peduncle to head measures. Backward stepwise discriminant function analysis retained two head measures, three midbody measures, and four caudal peduncle measures; correct classification rates when using these variables were 83% for leans, 80% for siscowets, and 83% for humpers, which suggests the measures we used for initial classification were consistent. Although clear ecological reasons for these differences are not readily apparent, patterns in misclassification rates may be consistent with evolutionary hypotheses for lake trout within the Laurentian Great Lakes.

  17. "An integral part of the children's education": placing sun protection in Auckland primary schools.

    PubMed

    Collins, Damian C A; Kearns, Robin A; Mitchell, Hannah

    2006-12-01

    Links between ozone depletion, sun exposure and the incidence of melanoma in later life have focussed public health attention on risk management, including attempts to curtail children's exposure to sunlight. Schools are potentially valuable sites in sun protection efforts, as they may combine behavioural messages with protective environments. In this paper, we outline the sun-related attitudes and policies of a random sample of 20 Auckland primary schools, and situate them within the framework of the new public health. We observe that while the state requires schools to provide students with a safe environment, there is no explicit guidance on what this means in terms of sun protection. Accordingly, schools' responses vary according to the perceptions and priorities of individual principals. We conclude that while school spaces are being transformed through the public health focus on the risks of UV exposure, the neoliberal educational landscape in New Zealand appears ambiguous in its support for health promotion.

  18. LakeMIP Kivu: Evaluating the representation of a large, deep tropical lake by a set of 1-dimensional lake models

    NASA Astrophysics Data System (ADS)

    Thiery, Wim; Stepanenko, Viktor; Darchambeau, François; Joehnk, Klaus; Martynov, Andrey; Mironov, Dmitrii; Perroud, Marjorie; van Lipzig, Nicole

    2013-04-01

    The African great lakes are of utmost importance for the local economy (fishing), as well as being essential to the survival of the local people. During the last decades, these lakes experienced fast changes in ecosystem structure and functioning and their future evolution is a major concern. In this study, for the first time a set of one-dimensional lake models are evaluated over East-Africa, in particular over Lake Kivu (2.28 °S; 28.98 °E). The unique limnology of meromictic Lake Kivu, with the importance of salinity and geothermal springs in a tropical high-altitude climate, presents a worthy challenge to the 1D-lake models currently involved in the Lake Model Intercomparison Project (LakeMIP). Furthermore, this experiment will serve as the basis for a future, more complex intercomparison, coupling lake models with atmospheric circulation models to analyse climate change effects on the lake. Meteorological observations from two automatic weather stations, one at Kamembe airport (Rwanda, 2003-2008), the other at ISP Bukavu (DRC, 2003-2011), are used to drive each of these models. For the evaluation, a unique dataset is used which contains over 150 temperature profiles recorded since 2002. The standard LakeMIP protocol is adapted to mirror the limnological conditions in Lake Kivu and to unify model parameters as far as possible. Since some lake models do not account for salinity and its effect upon lake stratification, two sets of simulations are performed with each model: one for the freshwater layer only (60 m) and one for the average lake depth (240 m) including salinity. Therewith, on the one hand it is investigated whether each model is able to reproduce the correct mixing regime in Lake Kivu and captures the controlling of this seasonality by the relative humidity, which constrains evaporation except during summer (JJA). On the other hand, the ability of different models to simulate salinity- and geothermal-induced effects upon deep water stratification is

  19. Planetary Lake Lander - A Robotic Sentinel to Monitor a Remote Lake

    NASA Technical Reports Server (NTRS)

    Pedersen, Liam; Smith, Trey; Lee, Susan; Cabrol, Nathalie; Rose, Kevin

    2012-01-01

    The Planetary Lake Lander Project is studying the impact of rapid deglaciation at a high altitude alpine lake in the Andes, where disrupted environmental, physical, chemical, and biological cycles result in newly emerging natural patterns. The solar powered Lake Lander robot is designed to monitor the lake system and characterize both baseline characteristics and impacts of disturbance events such as storms and landslides. Lake Lander must use an onboard adaptive science-on-the-fly approach to return relevant data about these events to mission control without exceeding limited energy and bandwidth resources. Lake Lander carries weather sensors, cameras and a sonde that is winched up and down the water column to monitor temperature, dissolved oxygen, turbidity and other water quality parameters. Data from Lake Lander is returned via satellite and distributed to an international team of scientists via web-based ground data systems. Here, we describe the Lake Lander Project scientific goals, hardware design, ground data systems, and preliminary data from 2011. The adaptive science-on-the-fly system will be described in future papers.

  20. Patterns of organochlorine contamination in lake trout from Wisconsin waters of the Great Lakes

    USGS Publications Warehouse

    Miller, Michael A.; Madenjian, Charles P.; Masnado, Robert G.

    1992-01-01

    To investigate spatial and temporal patterns of organochlorine contamination in lake trout from Wisconsin waters of the Great Lakes, we examined laboratory contaminant analysis data of muscle tissue samples from Lake Michigan (n=317) and Lake Superior (n=53) fish. Concentrations of polychlorinated biphenyls (PCBs), chlordane, and dieldrin, reported as mg/kg wet weight in 620 mm to 640 mm mean length Lake Michigan lake trout, decreased over time. Mean total PCB concentration declined exponentially from 9.7 in 1975 to 1.9 in 1990. Total chlordane concentration declined 63 percent from 0.48 in 1983 to 0.18 in 1990, and dieldrin declined 52 percent during this same period, from 0.21 to 0.10. The bioaccumulation rate of PCBs is significantly lower for lake trout inhabiting Lake Michigan's midlake reef complex, compared to lake trout from the nearshore waters of western Lake Michigan. Organochlorine compound concentrations were greater in Lake Michigan lake trout than Lake Superior fish. Lake Superior lean lake trout and siscowet exhibited similar rates of PCB bioaccumulation despite major differneces in muscle tissue lipid content between the two subspecies. The lack of a significant difference in the PCB bioaccumulation rates of lean trout and siscowet suggests that lipid content may not be an important factor influencing PCB bioaccumulation in lake trout, within the range of lipid concentrations observed. Relative concentrations of the various organochlorine contaminants found in lake trout were highly correlated, suggesting similar mass balance processes for these compounds. Evidence presented revealing spatial and temporal patterns of organochlorine contamination may be of value in reestablishing self-sustaining populations of lake trout in Lake Michigan.

  1. Winter diet of lake herring (Coregonus artedi) in western Lake Superior

    USGS Publications Warehouse

    Link, Jason; Selgeby, James H.; Hoff, Michael H.; Haskell, Craig

    1995-01-01

    Lake herring (Coregonus artedi) and zooplankton samples were simultaneously collected through the ice in the Apostle Islands region of western Lake Superior to provide information on the winter feeding ecology of lake herring. Zooplankton constituted the entire diet of the 38 lake herring collected for this study. We found no evidence of piscivory, although it has been reported by anglers. Diet selectivities were calculated using a Wilcoxon signed-ranks test and showed a preference of lake herring for larger zooplankton, especially Diaptomus sicilis, whereas the smaller copepod,Cyclops bicuspidatus thomasi, and immature copepod stages were selected against. These data document that overwintering copepods are food for a broad size range of lake herring in winter.

  2. Mono Lake, California

    NASA Image and Video Library

    2017-03-24

    In eastern California, along the western edge of the Great Basin, sits Mono Lake. This is a salty remnant of a wetter era. Estimates are that the lake existed for at least 760,000 years. Now surrounded by mountain ranges, however, Mono Lake has no outlet; water entering the lake can only evaporate away, so Mono Lake is saltier than the ocean. South of the lake appear some of the geologic features known as Mono Craters. Geologists estimate that the Mono Craters last erupted about 650 years ago. The image was acquired July 7, 2016, covers an area of 22.6 by 34 km, and is located at 37.9 degrees north, 119 degrees west. http://photojournal.jpl.nasa.gov/catalog/PIA21518

  3. Synthetic Musk Fragrances in Lake Erie and Lake Ontario Sediment Cores

    PubMed Central

    Peck, Aaron M.; Linebaugh, Emily K.; Hornbuckle, Keri C.

    2009-01-01

    Two sediment cores collected from Lake Ontario and Lake Erie were sectioned, dated, and analyzed for five polycyclic musk fragrances and two nitro musk fragrances. The polycyclic musk fragrances were HHCB (Galaxolide), AHTN (Tonalide), ATII (Traseolide), ADBI (Celestolide), and AHMI (Phantolide). The nitro musk fragrances were musk ketone and musk xylene. Chemical analysis was performed by gas chromatography/mass spectrometry (GC/MS) and results from Lake Erie were confirmed using gas chromatography/triple-quadrupole mass spectrometry (GC/MS/MS). The chemical signals observed at the two sampling locations were different from each other due primarily to large differences in the sedimentation rates at the two sampling locations. HHCB was detected in the Lake Erie core while six compounds were detected in the Lake Ontario core. Using measured fragrance and 210Pb activity, the burden of synthetic musk fragrances estimated from these sediment cores is 1900 kg in Lake Erie and 18000 kg in Lake Ontario. The input of these compounds to the lakes is increasing. The HHCB accumulation rates in Lake Erie for 1979-2003 and 1990-2003 correspond to doubling times of 16 ± 4 yr and 8 ± 2 yr, respectively. The results reflect current U.S. production trends for the sum of all fragrance compounds. PMID:17007119

  4. Status of lake trout rehabilitation in the Northern Refuge of Lake Michigan

    USGS Publications Warehouse

    Madenjian, Charles P.; DeSorcie, Timothy J.

    1999-01-01

    The Northern Refuge in Lake Michigan was established in 1985 as part of a rehabilitation program to stock yearling lake trout Salvelinus namaycush in areas with the best potential for success. Stocking of hatchery-reared lake trout within the refuge began in 1986 at three reefs: Boulder Reef, Gull Island Reef, and Richards Reef. On each reef from 1991 to 1997 we conducted gill-net surveys during the fall spawning season to evaluate performance of adult lake trout, and we conducted beam trawl surveys for naturally reproduced age-0 lake trout in the spring. Criteria to evaluate performance included spawner density, growth, maturity, and mortality. We found no evidence of natural reproduction by lake trout from our surveys. Nevertheless, density of spawning lake trout on Boulder Reef (69 fish/305 m of gill net/night) and Gull Island Reef (34 fish/305 m of gill net/night) appeared to be sufficiently high to initiate a self-sustaining population. Growth and maturity rates of lake trout in the Northern Refuge were similar to those for lake trout stocked in the nearshore region of Lake Michigan. In the Northern Refuge, growth rate for the Marquette strain of lake trout was slightly higher than for the Lewis Lake strain. Annual mortality estimates from catch curve analyses ranged from 0.46 to 0.41, and therefore, these estimates approached a level that was considered to be sufficiently low to allow for a self-sustaining population. Thus, it appeared that the lack of evidence for natural reproduction by lake trout in the Northern Refuge should not be attributed to inability of the population to attain a sufficiently large stock of spawners.

  5. Water-Quality and Lake-Stage Data for Wisconsin Lakes, Water Year 2007

    USGS Publications Warehouse

    Wisconsin Water Science Center Lake-Studies Team: Rose, W. J.; Garn, H.S.; Goddard, G.L.; Marsh, S.B.; Olson, D.L.; Robertson, Dale M.

    2008-01-01

    The U.S. Geological Survey (USGS), in cooperation with local and other agencies, collects data at selected lakes throughout Wisconsin. These data, accumulated over many years, provide a data base for developing an improved understanding of the water quality of lakes. To make these data available to interested parties outside the USGS, the data are published annually in this report series. The locations of water-quality and lake-stage stations in Wisconsin for water year 2007 are shown in figure 1. A water year is the 12-month period from October 1 through September 30. It is designated by the calendar year in which it ends. Thus, the period October 1, 2005 through September 30, 2007 is called 'water year 2007.' The purpose of this report is to provide information about the chemical and physical characteristics of Wisconsin lakes. Data that have been collected at specific lakes, and information to aid in the interpretation of those data, are included in this report. Data collected include measurements of in-lake water quality and lake stage. Time series of Secchi depths, surface total phosphorus and chlorophyll a concentrations collected during non-frozen periods are included for all lakes. Graphs of vertical profiles of temperature, dissolved oxygen, pH, and specific conductance are included for sites where these parameters were measured. Descriptive information for each lake includes: location of the lake, area of the lake?s watershed, period for which data are available, revisions to previously published records, and pertinent remarks. Additional data, such as streamflow and water quality in tributary and outlet streams of some of the lakes, are published in another volume: 'Water Resources Data-Wisconsin, 2007.'

  6. 42. Peaks of Otter, Abbott Lake. View across lake to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. Peaks of Otter, Abbott Lake. View across lake to peaks of Outter Lodge, completed in 1964. Construction of the lake got underway in 1964. Looking east-northeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  7. Placing private health care: reading Ascot Hospital in the landscape of contemporary Auckland.

    PubMed

    Kearns, Robin A; Barnett, J Ross; Newman, Daniel

    2003-06-01

    The closing years of the 20th century were a time in New Zealand dominated by health care reforms inspired by neo-liberal ideology. The result has been changing geographies of public and private health care providers and the evolution of a new discourse of health care. Ascot Integrated Hospital, situated in the affluent Auckland suburb of Remuera, opened in 1999, reflecting and projecting this new discourse. It is a pioneer, competing for patient patronage in a contracting market for surgical and medical providers. In this paper we survey the recent history of private hospital developments in New Zealand, then more closely consider the Ascot, a hospital that has deployed language to construct itself and its achievements in the public imagination. Given the context of an extremely competitive environment for private patients, this construction glamorises medicine and links healing with a contrived place. We conclude that texts associated with the Ascot provide a useful vehicle for advancing cultural geographies of health care and ideas of the place of hospitals in western capitalist countries.

  8. Patterns of egg deposition by lake trout and lake whitefish at Tawas artificial Reef, Lake Huron, 1990-1993

    USGS Publications Warehouse

    Foster, N.R.; Kennedy, G.W.; Munawar, M.; Edsall, T.; Leach, J.

    1995-01-01

    In August 1987, the Michigan Department of Natural Resources (MDNR), with the help and co-sponsorship of Walleyes for Iosco County, constructed Tawas artificial reef to improve recreational fishing in Tawas Bay. Post-construction assessment in October, 1987, by the MDNR found twice as many adult lake trout in a gill net set on the reef as in a similar net set off the reef, indicating that lake trout already had begun to investigate this new habitat. Similar netting efforts in October 1989 caught three times as many adults on the reef as off it, even though the on-reef net was set for less than one third as long a period. Using a remotely operated vehicle (ROV), we detected prespawning aggregations of lake trout on the reef in fall 1989, and MDNR biologists set emergent fly traps on the reef in April-May 1990-1991. These fry traps captured several newly emerged lake trout and lake whitefish fry, demonstrating that eggs of both species has hatched successfully. Gill netting in 1992-1993 by U.S. Fish and Wildlife Service biologists netted large numbers of ripe lake trout in late October and ripe lake whitefish in early to mid-November. The purpose of this paper is to describe the relative quantities of eggs deposited and the spatial patterns of egg deposition by lake trout and lake whitefish at Tawas artificial reef during 1990-1993.

  9. Lake Powell

    NASA Image and Video Library

    2007-09-20

    The white ring around Lake Powell tells the story. The surface is down 98 feet. This is critical, because Powell, Lake Mead, and other lakes along the Colorado River provide water for millions of people in five states. We are in the eighth year of a drought on the Colorado River. This year was the driest year ever reported in Southern California, and there is a severe drought in Northern California, down to less than 30-percent of snow pack. This ASTER image of part of Lake Powell was acquired in 2001. The gray area depicts the shrunken, reduced 2007 lake extent compared to the extended, larger black area in 2001. The image covers an area of 24 x 30 km, and is centered near 37.1 degrees north latitude, 111.3 degrees west longitude. This image from NASA Terra satellite. http://photojournal.jpl.nasa.gov/catalog/PIA10614

  10. National Lakes Assessment: A Collaborative Survey of the Nation's Lakes

    EPA Science Inventory

    The National Lakes Assessment A Collaborative Survey of the Nation's Lakes presents the results of an unprecedented assessment of the nation’s lakes. This report is part of the National Aquatic Resource Surveys, a series of statistically based surveys designed to provide the pub...

  11. Combining probabilistic hazard assessment with cost-benefit analysis to support decision making in a volcanic crisis from the Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Sandri, Laura; Jolly, Gill; Lindsay, Jan; Howe, Tracy; Marzocchi, Warner

    2010-05-01

    One of the main challenges of modern volcanology is to provide the public with robust and useful information for decision-making in land-use planning and in emergency management. From the scientific point of view, this translates into reliable and quantitative long- and short-term volcanic hazard assessment and eruption forecasting. Because of the complexity in characterizing volcanic events, and of the natural variability of volcanic processes, a probabilistic approach is more suitable than deterministic modeling. In recent years, two probabilistic codes have been developed for quantitative short- and long-term eruption forecasting (BET_EF) and volcanic hazard assessment (BET_VH). Both of them are based on a Bayesian Event Tree, in which volcanic events are seen as a chain of logical steps of increasing detail. At each node of the tree, the probability is computed by taking into account different sources of information, such as geological and volcanological models, past occurrences, expert opinion and numerical modeling of volcanic phenomena. Since it is a Bayesian tool, the output probability is not a single number, but a probability distribution accounting for aleatory and epistemic uncertainty. In this study, we apply BET_VH in order to quantify the long-term volcanic hazard due to base surge invasion in the region around Auckland, New Zealand's most populous city. Here, small basaltic eruptions from monogenetic cones pose a considerable risk to the city in case of phreatomagmatic activity: evidence for base surges are not uncommon in deposits from past events. Currently, we are particularly focussing on the scenario simulated during Exercise Ruaumoko, a national disaster exercise based on the build-up to an eruption in the Auckland Volcanic Field. Based on recent papers by Marzocchi and Woo, we suggest a possible quantitative strategy to link probabilistic scientific output and Boolean decision making. It is based on cost-benefit analysis, in which all costs

  12. Hydrology of the Lake Deaton and Lake Okahumpka area, Northeast Sumter County, Florida

    USGS Publications Warehouse

    Simonds, Edward P.; German, E.R.

    1980-01-01

    The Floridan aquifer in the Lake Deaton and Lake Okahumpka area is 50 to 130 feet below land surface. During the 16-year period 1963-78 lake evaporation exceeded rainfall by 0.4 inches. Drainage from Lake Deaton and its surrounding area goes into Chitty Chatty Creek and on the Hogeye Sink when the altitude of the potentiometric surface of the Floridan aquifer is low. During a higher altitude of the Floridan potentiometric surface, Hogeye Sink may discharge water; this water, along with the normal runoff, goes into Lake Okahumpka. Average lake fluctuation is 1.5 to 2.0 feet per year. Lake Deaton supports a large population of blue-green algae and Lake Okahumpka is choked with aquatic plants. The water quality of the two lakes differ, with Lake Deaton having a sodium chloride water and Lake Okahumpka having a calcium bicarbonate water. Analysis of water and bottom material samples showed that only cadmium and mercury exceeded the Florida Department of Environmental Regulation 's criteria for Class III waters; however, the amounts detected were at or slightly above the limits of the analytical method. (USGS)

  13. Strand-plain evidence for late Holocene lake-level variations in Lake Michigan

    USGS Publications Warehouse

    Thompson, T.A.; Baedke, S.J.

    1997-01-01

    Lake level is a primary control on shoreline behavior in Lake Michigan. The historical record from lake-level gauges is the most accurate source of information on past lake levels, but the short duration of the record does not permit the recognition of long-term patterns of lake-level change (longer than a decade or two). To extend the record of lake-level change, the internal architecture and timing of development of five strand plains of late Holocene beach ridges along the Lake Michigan coastline were studied. Relative lake-level curves for each site were constructed by determining the elevation of foreshore (swash zone) sediments in the beach ridges and by dating basal wetland sediments in the swales between ridges. These curves detect long-term (30+ yr) lake-level variations and differential isostatic adjustments over the past 4700 yr at a greater resolution than achieved by other studies. The average timing of beach-ridge development for all sites is between 29 and 38 yr/ridge. This correspondence occurs in spite of the embayments containing the strand plains being different in size, orientation, hydrographic regime, and available sediment type and caliber. If not coincidental, all sites responded to a lake-level fluctuation of a little more than three decades in duration and a range of 0.5 to 0.6 m. Most pronounced in the relative lake-level curves is a fluctuation of 120-180 yr in duration. This ???150 yr variation is defined by groups of four to six ridges that show a rise and fall in foreshore elevations of 0.5 to 1.5 m within the group. The 150 yr variation can be correlated between sites in the Lake Michigan basin. The ???30 and 150 yr fluctuations are superimposed on a long-term loss of water to the Lake Michigan basin and differential rates of isostatic adjustment.

  14. Ethnic disparities in repeat caesarean rates at Auckland Hospital.

    PubMed

    Wise, Michelle R; Anderson, Ngaire H; Sadler, Lynn

    2013-10-01

    New Zealand guidelines recommend that information regarding childbirth choices be given to women with previous caesarean, so they can make informed decisions about their care. We hypothesised that rates of trial of labour (TOL) and vaginal birth after caesarean (VBAC) would vary by women's ethnicity. To estimate the association of ethnicity with TOL and VBAC rates. Clinical data were used to identify women who gave birth at Auckland Hospital in 2006-2009 with history of previous caesarean eligible for TOL. Multivariable models were used to estimate the association of women's characteristics (ethnicity, age, socio-economic status (SES), height, body mass index, lead maternity carer, diabetes, hypertension, haemorrhage, labour induction, gestational age) with rates of TOL and VBAC. In the study cohort of 2400 women, the TOL rate was 39.5%; the VBAC rate was 57.4%. Pacific women were twice as likely to have TOL, while Asian and non-New Zealand European women were half as likely to have VBAC, compared with New Zealand European women. Women in more deprived areas were more likely to have TOL, but SES was not associated with VBAC rates. Women under the care of private obstetricians were least likely to have TOL or VBAC. There are ethnic disparities in TOL and VBAC rates at our hospital. Strategies need to be developed to ensure that women of all ethnicities have access to both options for mode of delivery. © 2013 The Authors ANZJOG © 2013 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  15. Water-Quality and Lake-Stage Data for Wisconsin Lakes, Water Year 2006

    USGS Publications Warehouse

    Rose, W.J.; Garn, H.S.; Goddard, G.L.; Marsh, S.B.; Olson, D.L.; Robertson, Dale M.

    2007-01-01

    The U.S. Geological Survey (USGS), in cooperation with local and other agencies, collects data at selected lakes throughout Wisconsin. These data, accumulated over many years, provide a data base for developing an improved understanding of the water quality of lakes. To make these data available to interested parties outside the USGS, the data are published annually in this report series. The locations of water-quality and lake-stage stations in Wisconsin for water year 2006 are shown in figure 1. A water year is the 12-month period from October 1 through September 30. It is designated by the calendar year in which it ends. Thus, the period October 1, 2005 through September 30, 2006 is called 'water year 2006.' The purpose of this report is to provide information about the chemical and physical characteristics of Wisconsin lakes. Data that have been collected at specific lakes, and information to aid in the interpretation of those data, are included in this report. Data collected include measurements of in-lake water quality and lake stage. Time series of Secchi depths, surface total phosphorus and chlorophyll a concentrations collected during non-frozen periods are included for all lakes. Graphs of vertical profiles of temperature, dissolved oxygen, pH, and specific conductance are included for sites where these parameters were measured. Descriptive information for each lake includes: location of the lake, area of the lake's watershed, period for which data are available, revisions to previously published records, and pertinent remarks. Additional data, such as streamflow and water quality in tributary and outlet streams of some of the lakes, are published in another volume: 'Water Resources Data-Wisconsin, 2006.' Water-resources data, including stage and discharge data at most streamflow-gaging stations, are available through the World Wide Web on the Internet. The Wisconsin Water Science Center's home page is at http://wi.water.usgs.gov/. Information on the

  16. Diet and prey selection by Lake Superior lake trout during springs 1986-2001

    USGS Publications Warehouse

    Ray, B.A.; Hrabik, T.R.; Ebener, M.P.; Gorman, O.T.; Schreiner, D.R.; Schram, S.T.; Sitar, S.P.; Mattes, W.P.; Bronte, C.R.

    2007-01-01

    We describe the diet and prey selectivity of lean (Salvelinus namaycush namaycush) and siscowet lake trout (S. n. siscowet) collected during spring (April–June) from Lake Superior during 1986–2001. We estimated prey selectivity by comparing prey numerical abundance estimates from spring bottom trawl surveys and lake trout diet information in similar areas from spring gill net surveys conducted annually in Lake Superior. Rainbow smelt (Osmerus mordax) was the most common prey and was positively selected by both lean and siscowet lake trout throughout the study. Selection by lean lake trout for coregonine (Coregonus spp.) prey increased after 1991 and corresponded with a slight decrease in selection for rainbow smelt. Siscowet positively selected for rainbow smelt after 1998, a change that was coincident with the decrease in selection for this prey item by lean lake trout. However, diet overlap between lean and siscowet lake trout was not strong and did not change significantly over the study period. Rainbow smelt remains an important prey species for lake trout in Lake Superior despite declines in abundance.

  17. Biology, population structure, and estimated forage requirements of lake trout in Lake Michigan

    USGS Publications Warehouse

    Eck, Gary W.; Wells, LaRue

    1983-01-01

    Data collected during successive years (1971-79) of sampling lake trout (Salvelinus namaycush) in Lake Michigan were used to develop statistics on lake trout growth, maturity, and mortality, and to quantify seasonal lake trout food and food availability. These statistics were then combined with data on lake trout year-class strengths and age-specific food conversion efficiencies to compute production and forage fish consumption by lake trout in Lake Michigan during the 1979 growing season (i.e., 15 May-1 December). An estimated standing stock of 1,486 metric tons (t) at the beginning of the growing season produced an estimated 1,129 t of fish flesh during the period. The lake trout consumed an estimated 3,037 t of forage fish, to which alewives (Alosa pseudoharengus) contributed about 71%, rainbow smelt (Osmerus mordax) 18%, and slimy sculpins (Cottus cognatus) 11%. Seasonal changes in bathymetric distributions of lake trout with respect to those of forage fish of a suitable size for prey were major determinants of the size and species compositions of fish in the seasonal diet of lake trout.

  18. Lakes and lake-like waters of the Hawaiian Archipelago

    USGS Publications Warehouse

    Maciolek, J.A.

    1982-01-01

    This summary of Hawaiian lacustrine limnology is based on 12 years of field and literature surveys of archipelagic inland waters. Lakes here are distinguished from other standing waters by limits on surface oceanic area (> 0.1 ha) and depth (> 2 m), and by the absence of flatural surface oceanic connection. A variety of extinct and existing water bodies, sometimes referred to as lakes, are noted. Six lakes are described. Five of them are in crater basins, 3 are freshwater, and 2 are elevated (highest = 3969 m). The scarcity of elevated lakes results from general permeability of the substrata. Among the 6 lakes, surface areas range from 0.22 to 88 ha and maximum depths from 3 to 248 m. Naturally occurring aquatic biota generally is low in species diversity except for phytoplankton; fishes and submersed vascular plants are absent. Two lowland lakes, freshwater Green (Wai a Pele) and saline Kauhak6, are described for the first time. Profundal Kauhak6, 248 m deep, has a surface area of only 0.35 ha, which results in an extraordinary relative depth of 370%. It is permanently stratified, a condition apparently due primarily to the unique morphometry of its basin. 

  19. Ethnic disparities in incidence of stroke subtypes: Auckland Regional Community Stroke Study, 2002-2003.

    PubMed

    Feigin, Valery; Carter, Kristie; Hackett, Maree; Barber, P Alan; McNaughton, Harry; Dyall, Lorna; Chen, Mei-hua; Anderson, Craig

    2006-02-01

    Limited population-based data exist on differences in the incidence of major pathological stroke types and ischaemic stroke subtypes across ethnic groups. We aimed to provide such data within the large multi-ethnic population of Auckland, New Zealand. All first-ever cases of stroke (n=1423) in a population-based register in 940 000 residents (aged 15 years) in Auckland, New Zealand, for a 12-month period in 2002-2003, were classified into ischaemic stroke, primary intracerebral haemorrhage (PICH), subarachnoid haemorrhage, and undetermined stroke, according to standard definitions and results of neuroimaging/necropsy (in over 90% of cases). Ischaemic stroke was further classified into five subtypes. Ethnicity was self-identified and grouped as New Zealand (NZ)/European, Maori/Pacific, and Asian/other. Incidence rates were standardised to the WHO world population by the direct method, and differences in rates between ethnic groups expressed as rate ratios (RRs), with NZ/European as the reference group. In NZ/European people, ischaemic stroke comprised 73%, PICH 11%, and subarachnoid haemorrhage 6%, but PICH was higher in Maori/Pacific people (17%) and in Asian/other people (22%). Compared with NZ/European people, age-adjusted RRs for PICH were 2.7 (95% CI 1.8-4.0) and 2.3 (95% CI 1.4-3.7) among Maori/Pacific and Asian/other people, respectively. The corresponding RR for ischaemic stroke was greater for Maori/Pacific people (1.7 [95% CI 1.4-2.0]), particularly embolic stroke, and for Asian/other people (1.3 [95% CI 1.0-1.7]). The onset of stroke in Maori/Pacific and Asian/other people began at significantly younger ages (62 years and 64 years, respectively) than in NZ/Europeans (75 years; p<0.0001). There were ethnic differences in the risk factor profiles (such as age, sex, hypertension, cardiac disease, diabetes, hypercholesterolaemia, smoking status, overweight) for the stroke types and subtypes. Compared to NZ/Europeans, Maori/Pacific and Asian/other people are

  20. Lake Powell

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The white ring around Lake Powell tells the story. The surface is down 98 feet. This is critical, because Powell, Lake Mead, and other lakes along the Colorado River provide water for millions of people in five states. We are in the eighth year of a drought on the Colorado River. This year was the driest year ever reported in Southern California, and there is a severe drought in Northern California, down to less than 30-percent of snow pack. This ASTER image of part of Lake Powell was acquired in 2001. The gray area depicts the shrunken, reduced 2007 lake extent compared to the extended, larger black area in 2001.

    The image covers an area of 24 x 30 km, and is centered near 37.1 degrees north latitude, 111.3 degrees west longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  1. Ciscoes (Coregonus, subgenus Leucichthys) of the Laurentian Great Lakes and Lake Nipigon

    USGS Publications Warehouse

    Eshenroder, Randy L.; Vecsei, Paul; Gorman, Owen T.; Yule, Daniel; Pratt, Thomas C.; Mandrak, Nicholas E.; Bunnell, David B.; Muir, Andrew M.

    2016-01-01

    This study of the ciscoes (Coregonus, subgenus Leucichthys) of the Great Lakes and Lake Nipigon represents a furtherance through 2015 of field research initiated by Walter Koelz in 1917 and continued by Stanford Smith in the mid-1900s—a period spanning nearly a century. Like Koelz’s study, this work contains information on taxonomy, geographical distribution, ecology, and status of species (here considered forms). Of the seven currently recognized forms (C. artedi, C. hoyi, C. johannae, C. kiyi, C. nigripinnis, C. reighardi, and C. zenithicus) described by Koelz as major in his 1929 monograph, two (C. johannae and C. reighardi) are extinct. In addition, C. alpenae, described by Koelz but subsequently synonymized with C. zenithicus, although extinct, is recognized as valid making a total of eight major forms. Six of these forms, all but C. artedi and C. hoyi, have been lost from Lake Michigan, and seven have been lost from Lake Huron, leaving in Lake Huron only C. artedi and an introgressed deepwater form that we term a hybrid swarm. C. artedi appears, like its sister form C. alpenae, to have been lost from Lake Erie. Only C. artedi remains extant in Lake Ontario, its three sister forms (C. hoyi, C. kiyi, and C. reighardi) having disappeared long ago.Lakes Superior and Nipigon have retained their original species flocks consisting of four forms each: C. artedi, C. hoyi, and C. zenithicus in both lakes; C. kiyi in Lake Superior; and C. nigripinnis in Lake Nipigon. Morphological deviations from the morphotypes described by Koelz have been modest in contemporary samples. Overall, C. kiyi and C. artedi were the most morphologically stable forms while C. hoyi, C. nigripinnis, and C. zenithicus were the least stable. Although contemporary populations of C. artedi from Lakes Michigan and Huron are highly diverged from the morphotypes described by Koelz, the contemporary samples were of undescribed deep-bodied forms unlikely to have been sampled by Koelz because of

  2. Sedimentary constraints on late Quaternary lake-level fluctuations at Bear Lake, Utah and Idaho

    USGS Publications Warehouse

    Smoot, J.P.; Rosenbaum, J.G.

    2009-01-01

    A variety of sedimentological evidence was used to construct the lake-level history for Bear Lake, Utah and Idaho, for the past ???25,000 years. Shorelines provide evidence of precise lake levels, but they are infrequently preserved and are poorly dated. For cored sediment similar to that in the modern lake, grain-size distributions provide estimates of past lake depths. Sedimentary textures provide a highly sensitive, continuous record of lake-level changes, but the modern distribution of fabrics is poorly constrained, and many ancient features have no modern analog. Combining the three types of data yields a more robust lake-level history than can be obtained from any one type alone. When smooth age-depth models are used, lake-level curves from multiple cores contain inconsistent intervals (i.e., one record indicates a rising lake level while another record indicates a falling lake level). These discrepancies were removed and the multiple records were combined into a single lake-level curve by developing age-depth relations that contain changes in deposition rate (i.e., gaps) where indicated by sedimentological evidence. The resultant curve shows that, prior to 18 ka, lake level was stable near the modern level, probably because the lake was overflowing. Between ca. 17.5 and 15.5 ka, lake level was ???40 m below the modern level, then fluctuated rapidly throughout the post-glacial interval. Following a brief rise centered ca. 15 ka ( = Raspberry Square phase), lake level lowered again to 15-20 m below modern from ca. 14.8-11.8 ka. This regression culminated in a lowstand to 40 m below modern ca. 12.5 ka, before a rapid rise to levels above modern ca. 11.5 ka. Lake level was typically lower than present throughout the Holocene, with pronounced lowstands 15-20 m below the modern level ca. 10-9, 7.0, 6.5-4.5, 3.5, 3.0-2.5, 2.0, and 1.5 ka. High lake levels near or above the modern lake occurred ca. 8.5-8.0, 7.0-6.5, 4.5-3.5, 2.5, and 0.7 ka. This lake-level history

  3. Fat content of the flesh of siscowets and lake trout from Lake Superior

    USGS Publications Warehouse

    Eschmeyer, Paul H.; Phillips, Arthur M.

    1965-01-01

    Samples of flesh were excised from the middorsal region of 67 siscowets (Salvelinus namaycush siscowet) and 46 lake trout (Salvelinus n. namaycush) collected from Lake Superior. Chemical analysis of the samples revealed a range in fat content (dry weight) of 32.5 to 88.8 per cent in siscowets and 6.6 to 52.3 per cent in lake trout. Percentage fat increased progressively with increase in length of fish in both forms, but the average rate of increase was far greater for siscowets than for lake trout at lengths between 12 and 20 inches. Despite substantial individual variation, the percentage fat in the two forms was widely different and without overlap at all comparable lengths. The range in iodine number of the fat was 100 to 160 for siscowets and 103 to 161 for lake trout; average values were generally lower for siscowets than for lake trout among fish of comparable length. Percentage fat and relative weight were not correlated significantly in either subspecies. The fat content of flesh samples from a distinctive subpopulation of Lake Superior lake trout known as 'humpers' was more closely similar to that of typical lean lake trout than to siscowets, but the rate of increase in fat with increasing length was greater than for lean lake trout. Flesh samples from hatchery-reared stocks of lake trout, hybrid lake trout X siscowets, and siscowets tended to support the view that the wide difference in fat content between siscowets and lake trout is genetically determined.

  4. 77 FR 9652 - Proposed CERCLA Administrative Cost Recovery Settlement; Lake Linden Superfund Site in Lake...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-17

    ... Settlement; Lake Linden Superfund Site in Lake Linden, Houghton County, MI AGENCY: Environmental Protection... concerning the Lake Linden Superfund Site in Lake Linden, Houghton County, Michigan with Honeywell Specialty...-6609. Comments should reference the Lake Linden Superfund Site in Lake Linden, Houghton County...

  5. High-precision 40Ar/39Ar dating of Quaternary basalts from Auckland Volcanic Field, New Zealand, with implications for eruption rates and paleomagnetic correlations

    NASA Astrophysics Data System (ADS)

    Leonard, Graham S.; Calvert, Andrew T.; Hopkins, Jenni L.; Wilson, Colin J. N.; Smid, Elaine R.; Lindsay, Jan M.; Champion, Duane E.

    2017-09-01

    The Auckland Volcanic Field (AVF), which last erupted ca. 550 years ago, is a late Quaternary monogenetic basaltic volcanic field (ca. 500 km2) in the northern North Island of New Zealand. Prior to this study only 12 out of the 53 identified eruptive centres of the AVF had been reliably dated. Careful sample preparation and 40Ar/39Ar analysis has increased the number of well-dated centres in the AVF to 35. The high precision of the results is attributed to selection of fresh, non-vesicular, non-glassy samples from lava flow interiors. Sample selection was coupled with separation techniques that targeted only the groundmass of samples with < 5% glass and with groundmass feldspars > 10 μm wide, coupled with ten-increment furnace step-heating of large quantities (up to 200 mg) of material. The overall AVF age data indicate an onset at 193.2 ± 2.8 ka, an apparent six-eruption flare-up from 30 to 34 ka, and a ≤ 10 kyr hiatus between the latest and second-to-latest eruptions. Such non-uniformity shows that averaging the number of eruptions over the life-span of the AVF to yield a mean eruption rate is overly simplistic. Together with large variations in eruption volumes, and the large sizes and unusual chemistry within the latest eruptions (Rangitoto 1 and Rangitoto 2), our results illuminate a complex episodic eruption history. In particular, the rate of volcanism in AVF has increased since 60 ka, suggesting that the field is still in its infancy. Multiple centres with unusual paleomagnetic inclination and declination orientations are confirmed to fit into a number of geomagnetic excursions, with five identified in the Mono Lake, two within the Laschamp, one within the post-Blake or Blake, and two possibly within the Hilina Pali.

  6. Long-term simulations of dissolved oxygen concentrations in Lake Trout lakes

    NASA Astrophysics Data System (ADS)

    Jabbari, A.; Boegman, L.; MacKay, M.; Hadley, K.; Paterson, A.; Jeziorski, A.; Nelligan, C.; Smol, J. P.

    2016-02-01

    Lake Trout are a rare and valuable natural resource that are threatened by multiple environmental stressors. With the added threat of climate warming, there is growing concern among resource managers that increased thermal stratification will reduce the habitat quality of deep-water Lake Trout lakes through enhanced oxygen depletion. To address this issue, a three-part study is underway, which aims to: analyze sediment cores to understand the past, develop empirical formulae to model the present and apply computational models to forecast the future. This presentation reports on the computational modeling efforts. To this end, a simple dissolved oxygen sub-model has been embedded in the one-dimensional bulk mixed-layer thermodynamic Canadian Small Lake Model (CSLM). This model is currently being incorporated into the Canadian Land Surface Scheme (CLASS), the primary land surface component of Environment Canada's global and regional climate modelling systems. The oxygen model was calibrated and validated by hind-casting temperature and dissolved oxygen profiles from two Lake Trout lakes on the Canadian Shield. These data sets include 5 years of high-frequency (10 s to 10 min) data from Eagle Lake and 30 years of bi-weekly data from Harp Lake. Initial results show temperature and dissolved oxygen was predicted with root mean square error <1.5 °C and <3 mgL-1, respectively. Ongoing work is validating the model, over climate-change relevant timescales, against dissolved oxygen reconstructions from the sediment cores and predicting future deep-water temperature and dissolved oxygen concentrations in Canadian Lake Trout lakes under future climate change scenarios. This model will provide a useful tool for managers to ensure sustainable fishery resources for future generations.

  7. A Dynamical Downscaling study over the Great Lakes Region Using WRF-Lake: Historical Simulation

    NASA Astrophysics Data System (ADS)

    Xiao, C.; Lofgren, B. M.

    2014-12-01

    As the largest group of fresh water bodies on Earth, the Laurentian Great Lakes have significant influence on local and regional weather and climate through their unique physical features compared with the surrounding land. Due to the limited spatial resolution and computational efficiency of general circulation models (GCMs), the Great Lakes are geometrically ignored or idealized into several grid cells in GCMs. Thus, the nested regional climate modeling (RCM) technique, known as dynamical downscaling, serves as a feasible solution to fill the gap. The latest Weather Research and Forecasting model (WRF) is employed to dynamically downscale the historical simulation produced by the Geophysical Fluid Dynamics Laboratory-Coupled Model (GFDL-CM3) from 1970-2005. An updated lake scheme originated from the Community Land Model is implemented in the latest WRF version 3.6. It is a one-dimensional mass and energy balance scheme with 20-25 model layers, including up to 5 snow layers on the lake ice, 10 water layers, and 10 soil layers on the lake bottom. The lake scheme is used with actual lake points and lake depth. The preliminary results show that WRF-Lake model, with a fine horizontal resolution and realistic lake representation, provides significantly improved hydroclimates, in terms of lake surface temperature, annual cycle of precipitation, ice content, and lake-effect snowfall. Those improvements suggest that better resolution of the lakes and the mesoscale process of lake-atmosphere interaction are crucial to understanding the climate and climate change in the Great Lakes region.

  8. Survival of lake trout eggs and fry reared in water from the upper Great Lakes

    USGS Publications Warehouse

    Mac, Michael J.; Edsall, Carol Cotant; Seelye, James G.

    1985-01-01

    As part of continuing studies of the reproductive failure of lake trout (Salvelinus namaycush) in Lake Michigan, we measured the survival of lake trout eggs and fry of different origins and reared in different environments. Eggs and milt were stripped from spawning lake trout collected in the fall of 1980 from southeastern Lake Michigan, northwestern Lake Huron, south central Lake Superior, and from hatchery brood stock. Eggs from all sources were incubated, and the newly hatched fry were reared for 139 days in lake water from each of the three upper Great Lakes and in well water. Survival of eggs to hatching at all sites was lowest for those from Lake Michigan (70% of fertilized eggs) and highest for eggs from Lake Superior (96%). Comparisons of incubation water from the different lakes indicated that hatching success of eggs from all sources was highest in Lake Huron water, and lowest in Lake Michigan water. The most notable finding was the nearly total mortality of fry from eggs of southeastern Lake Michigan lake trout. At all sites, the mean survival of Lake Michigan fry through 139 days after hatching was only 4% compared to near 50% for fry from the other three sources. In a comparison of the rearing sites, little influence of water quality on fry survival was found. Thus, the poor survival was associated with the source of eggs and sperm, not the water in which the fry were reared.

  9. Salt gland adenitis associated with bacteria in Blue Penguins (Eudyptula minor) from Hauraki Gulf (auckland, New Zealand).

    PubMed

    Suepaul, R B; Alley, M R; van Rensburg, M Jansen

    2010-01-01

    Three Blue Penguins (Eudyptula minor) were rescued between July 2006 and January 2007 off the east coast of Auckland, New Zealand. They were taken to a rehabilitation center, where they subsequently died in May 2007 and were submitted for necropsy. There was unilateral enlargement of the salt glands with disseminated small, pale, and firm foci in all birds. Histologic examination of the affected glands demonstrated the presence of multifocal granulomas and areas of severe squamous metaplasia of the collecting ducts. The remaining gland had areas of hyperplasia, dysplasia, and necrosis with a severe granulomatous inflammatory reaction. Intralesional gram-negative bacteria were detected, but, unfortunately, bacterial culture was unrewarding. No further cases were observed in penguins in the subsequent year, and the primary cause of the salt gland adenitis remains uncertain.

  10. The most acidified Austrian lake in comparison to a neutralized mining lake

    PubMed Central

    Moser, Michael; Weisse, Thomas

    2011-01-01

    This study investigated two mining lakes located in the north of Lower Austria. These lakes arose 45 years ago when open cast lignite mining ceased. The lakes are separated by a 7-m wide dam. Due to the oxidation of pyrite, both lakes have been acidified and exhibit iron, sulphate, and heavy metal concentrations several orders of magnitude higher than in circumneutral lakes. The water column of both lakes is divided into two layers by a pronounced chemocline. The smaller mining lake (AML), with pH close to of 2.6, is the most acidic lake in Austria, whereas flooding with stream water and by drainage from the surrounding fields neutralized the adjacent larger pit lake. The goal of our study was to investigate the effect of flooding on its physical, chemical and biological properties, in comparison to the pristine AML. Even relative to other extremely acidic lakes, the flora and fauna in the AML was reduced and composed of only two flagellate, one ciliate, and one rotifer species. The simplified pelagic food web in the mixolimnion consisted of heterotrophic bacteria, the mixotrophic flagellates Chlamydomonas acidophila and Ochromonas sp., the ciliate Oxytricha sp., and the rotifer Cephalodella sp. The latter two are as yet undescribed new species. The heliozoan Actinophrys sp. that may act as top predator occurred only in low abundance. The euglenid Lepocinclis buetschlii formed a stable deep chlorophyll maximum (DCM) at 7 m depth. Highest cell numbers of L. buetschlii in the DCM exceeded 108 L−1. The neutralized mining lake harboured higher plankton diversity similar to that of natural circumneutral lakes. A peak of at least 16 different phytoplankton taxa was observed during summer. The zooplankton consisted of several copepod species, daphnids and other cladocerans, and at least six different rotifer species. Several fish species occurred in the neutralized lake. Although the effect of non-permanent flooding was largely sustainable, interannual fluctuations of

  11. Seismic Data Reveal Lake-Level Changes in Lake Issyk-Kul, Kyrgyzstan

    NASA Astrophysics Data System (ADS)

    Gebhardt, C.; Spiess, V.; Keil, H.; Sauermilch, I.; Oberhänsli, H.; Abdrakhmatov, K.; De Batist, M. A.; Naudts, L.; De Mol, L.

    2013-12-01

    Lake Issyk-Kul is located in an intramontane basin of the Tien Shan, Kyrgyzstan, Central Asia, at 1607 m above sea level. It has formed in a tectonically active region with W-E striking major thrust zones both N and S of the lake. The lake is elongated with 180 km in W-E and 60 km in S-N direction and a water depth of roughly 670 m at its central plain. With a surface area of 6232 km2 and a total water colume of around 1736 km3, Lake Issyk-Kul is the second largest lake in the higher altitudes (De Batist et al., 2002). Two large delta areas have formed at the E and W end. Steep slopes at both the N and S shore separate rather narrow, shallow shelf areas from the central deeper plain. First seismic data of lake Issyk-Kul were acquired in 1982 by the Moscow University with a total of 31 profiles across the lake. In 1997 and 2001, a second and third seismic survey of the lake were carried out by the group of Marc De Batist (Ghent, Belgium) in cooperation with the Royal Museum of Central Africa (Tervuren, Belgium) and the SBRAS (Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia) using a sparker system with a single-channel streamer. These surveys were recently completed by a fourth expedition carried out by the University of Bremen in April 2013. During this expedition, 33 additional profiles were acquired with an airgun and a multi-channel streamer. The sparker surveys mostly cover the delta and shelf areas in high detail, while the airgun survey covers the deeper parts of the lake with penetration beyond the first multiple. Bathymetry data reveal that at the delta areas, the shelf is divided into two parts. The shallower comprises the part down to 110 m water depth with an average inclination of 0.5°, while the deeper part reaches from 110 m to 300 m water depth with an average slope inclination of 1°. Incised paleo-river channels of up to 2-3 km width and 50 m depth are visible both on the eastern and western shelf, but are limited to the

  12. Salting our freshwater lakes.

    PubMed

    Dugan, Hilary A; Bartlett, Sarah L; Burke, Samantha M; Doubek, Jonathan P; Krivak-Tetley, Flora E; Skaff, Nicholas K; Summers, Jamie C; Farrell, Kaitlin J; McCullough, Ian M; Morales-Williams, Ana M; Roberts, Derek C; Ouyang, Zutao; Scordo, Facundo; Hanson, Paul C; Weathers, Kathleen C

    2017-04-25

    The highest densities of lakes on Earth are in north temperate ecosystems, where increasing urbanization and associated chloride runoff can salinize freshwaters and threaten lake water quality and the many ecosystem services lakes provide. However, the extent to which lake salinity may be changing at broad spatial scales remains unknown, leading us to first identify spatial patterns and then investigate the drivers of these patterns. Significant decadal trends in lake salinization were identified using a dataset of long-term chloride concentrations from 371 North American lakes. Landscape and climate metrics calculated for each site demonstrated that impervious land cover was a strong predictor of chloride trends in Northeast and Midwest North American lakes. As little as 1% impervious land cover surrounding a lake increased the likelihood of long-term salinization. Considering that 27% of large lakes in the United States have >1% impervious land cover around their perimeters, the potential for steady and long-term salinization of these aquatic systems is high. This study predicts that many lakes will exceed the aquatic life threshold criterion for chronic chloride exposure (230 mg L -1 ), stipulated by the US Environmental Protection Agency (EPA), in the next 50 y if current trends continue.

  13. Morphometry and mixing regime of a tropical lake: Lake Nova (Southeastern Brazil).

    PubMed

    Gonçalves, Monica A; Garcia, Fábio C; Barroso, Gilberto F

    2016-09-01

    Lake Nova (15.5 km2) is the second largest lake in the Lower Doce River Valley (Southeastern Brazil). A better understanding of ecosystem structure and functioning requires knowledge about lake morphometry, given that lake basin form influences water column stratification. The present study aims to contribute to the understanding of relationship between morphometry and mixing patterns of deep tropical lakes in Brazil. Water column profiles of temperature and dissolved oxygen were taken on four sampling sites along the lake major axis during 2011, 2012 and 2013. The bathymetric survey was carried out in July 2011, along 131.7 km of hydrographic tracks yield 51,692 depth points. Morphometric features of lake size and form factors describe the relative deep subrectangular elongated basin with maximum length of 15.7 km, shoreline development index 5.0, volume of 0.23 km3, volume development of 1.3, and maximum, mean and relative depths of 33.9 m, 14.7 m and 0.7 %, respectively. The deep basin induces a monomictic pattern, with thermal stratification during the wet/warm season associated with anoxic bottom waters (1/3 of lake volume), and mixing during dry and cool season. Based on in situ measurements of tributary river discharges, theoretical retention time (RT) has been estimated in 13.4 years. The morphometry of Lake Nova promote long water RT and the warm monomictic mixing pattern, which is in accordance to the deep tropical lakes in Brazil.

  14. Incidence of stroke in women in Auckland, New Zealand. Ethnic trends over two decades: 1981-2003.

    PubMed

    Dyall, Lorna; Carter, Kristie; Bonita, Ruth; Anderson, Craig; Feigin, Valery; Kerse, Ngaire; Brown, Paul

    2006-11-17

    Although women have a greater lifetime risk of stroke than men, along with other gender differences in stroke, there is lack of reliable data on long-term trends in stroke in women. This paper presents the results of three population-based registers in Auckland (1981-1982, 1991-1992, and 2002-2003) which aimed to determine the trends in the incidence of stroke in New Zealand. This paper reports on the burden of stroke in women across different ethnic groups over the study period from 1981 to 2003. Three studies using similar methodology and overlapping case finding methods have been conducted in New Zealand to estimate trends in the incidence and outcome of stroke. The studies are recognised as meeting the 'ideal' criteria for stroke incidence and identify all first-ever and recurrent strokes in residents (aged greater than and equal to 15 years) the population of Auckland, New Zealand in the 12-month periods from 1981-1982, 1991-1992, and 2002-2003. There were totals of 307,578 strokes among women in 1981, 372,642 in 1991, and 470,727 in 2001, according to each Census representing over 50% of the population at each period (51%-54%). The WHO standard world population was used for direct age standardisation of annual rates (per 100,000 population), reported with 95% confidence intervals (CI). The proportion of women who have experienced a stroke did not change markedly over the study period but there were ethnic differences emerging which were related to population changes within the New Zealand population. Standardised stroke incidence in women was relatively stable across the three study periods (1981-1982), 133 [95% CI 118-151]; (1991-1992), 143 [95% CI 116-241]; and (2002-2003), 124 [95% CI 115-134]). However, a significant decline of 14% (95% CI 2%-29%) in rates of first-ever stroke was found between 1991-1992 and 2002-2003 in women. In contrast to the significant declines in event rates in European women over two decades (Rate ratio 0.84, 95% CI 0

  15. Characterization of Lake Michigan coastal lakes using zooplankton assemblages

    USGS Publications Warehouse

    Whitman, Richard L.; Nevers, Meredith B.; Goodrich, Maria L.; Murphy, Paul C.; Davis, Bruce M.

    2004-01-01

    Zooplankton assemblages and water quality were examined bi-weekly from 17 April to 19 October 1998 in 11 northeastern Lake Michigan coastal lakes of similar origin but varied in trophic status and limnological condition. All lakes were within or adjacent to Sleeping Bear Dunes National Lakeshore, Michigan. Zooplankton (principally microcrustaceans and rotifers) from triplicate Wisconsin net (80 I?m) vertical tows taken at each lake's deepest location were analyzed. Oxygen-temperature-pH-specific conductivity profiles and surface water quality were concurrently measured. Bray-Curtis similarity analysis showed small variations among sample replicates but large temporal differences. The potential use of zooplankton communities for environmental lake comparisons was evaluated by means of BIOENV (Primer 5.1) and principal component analyses. Zooplankton analyzed at the lowest identified taxonomic level yielded greatest sensitivity to limnological variation. Taxonomic and ecological aggregations of zooplankton data performed comparably, but less well than the finest taxonomic analysis. Secchi depth, chlorophyll a, and sulfate concentrations combined to give the best correlation with patterns of variation in the zooplankton data set. Principal component analysis of these variables revealed trophic status as the most influential major limnological gradient among the study lakes. Overall, zooplankton abundance was an excellent indicator of variation in trophic status.

  16. Human papillomavirus vaccination in Auckland: reducing ethnic and socioeconomic inequities.

    PubMed

    Poole, Tracey; Goodyear-Smith, Felicity; Petousis-Harris, Helen; Desmond, Natalie; Exeter, Daniel; Pointon, Leah; Jayasinha, Ranmalie

    2012-12-17

    The New Zealand HPV publicly funded immunisation programme commenced in September 2008. Delivery through a school based programme was anticipated to result in higher coverage rates and reduced inequalities compared to vaccination delivered through other settings. The programme provided for on-going vaccination of girls in year 8 with an initial catch-up programme through general practices for young women born after 1 January 1990 until the end of 2010. To assess the uptake of the funded HPV vaccine through school based vaccination programmes in secondary schools and general practices in 2009, and the factors associated with coverage by database matching. Retrospective quantitative analysis of secondary anonymised data School-Based Vaccination Service and National Immunisation Register databases of female students from secondary schools in Auckland District Health Board catchment area. Data included student and school demographic and other variables. Binary logistic regression was used to estimate odds ratios and significance for univariables. Multivariable logistic regression estimated strength of association between individual factors and initiation and completion, adjusted for all other factors. The programme achieved overall coverage of 71.5%, with Pacific girls highest at 88% and Maori at 78%. Girls higher socioeconomic status were more likely be vaccinated in general practice. School-based vaccination service targeted at ethic sub-populations provided equity for the Maori and Pacific student who achieved high levels of vaccination. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Lake Tahoe

    EPA Pesticide Factsheets

    Information on the Lake Tahoe watershed, EPA's protection efforts, water quality issues, effects of climate change, Lake Tahoe Total Maximum Daily Load (TMDL), EPA-sponsored projects, list of partner agencies.

  18. Geographical distributions of lake trout strains stocked in Lake Ontario

    USGS Publications Warehouse

    Elrod, Joseph H.; O'Gorman, Robert; Schneider, Clifford P.; Schaner, Ted

    1996-01-01

    Geographical distributions of lake trout (Salvelinus namaycush) stocked at seven locations in U.S. waters and at four locations in Canadian waters of Lake Ontario were determined from fish caught with gill nets in September in 17 areas of U.S. waters and at 10 fixed locations in Canadian waters in 1986-95. For fish of a given strain stocked at a given location, geographical distributions were not different for immature males and immature females or for mature males and mature females. The proportion of total catch at the three locations nearest the stocking location was higher for mature fish than for immature fish in all 24 available comparisons (sexes combined) and was greater for fish stocked as yearlings than for those stocked as fingerlings in all eight comparisons. Mature fish were relatively widely dispersed from stocking locations indicating that their tendency to return to stocking locations for spawning was weak, and there was no appreciable difference in this tendency among strains. Mature lake trout were uniformly distributed among sampling locations, and the strain composition at stocking locations generally reflected the stocking history 5 to 6 years earlier. Few lake trout moved across Lake Ontario between the north and south shores or between the eastern outlet basin and the main lake basin. Limited dispersal from stocking sites supports the concept of stocking different genetic strains in various parts of the lake with the attributes of each strain selected to match environmental conditions in the portion of the lake where it is stocked.

  19. Deglaciation, lake levels, and meltwater discharge in the Lake Michigan basin

    USGS Publications Warehouse

    Colman, Steven M.; Clark, J.A.; Clayton, L.; Hansel, A.K.; Larsen, C.E.

    1994-01-01

    The deglacial history of the Lake Michigan basin, including discharge and routing of meltwater, is complex because of the interaction among (1) glacial retreats and re-advances in the basin (2) the timing of occupation and the isostatic adjustment of lake outlets and (3) the depositional and erosional processes that left evidence of past lake levels. In the southern part of the basin, a restricted area little affected by differential isostasy, new studies of onshore and offshore areas allow refinement of a lake-level history that has evolved over 100 years. Important new data include the recognition of two periods of influx of meltwater from Lake Agassiz into the basin and details of the highstands gleaned from sedimentological evidence. Major disagreements still persist concerning the exact timing and lake-level changes associated with the Algonquin phase, approximately 11,000 BP. A wide variety of independent data suggests that the Lake Michigan Lobe was thin, unstable, and subject to rapid advances and retreats. Consequently, lake-level changes were commonly abrupt and stable shorelines were short-lived. The long-held beliefs that the southern part of the basin was stable and separated from deformed northern areas by a hinge-line discontinuity are becoming difficult to maintain. Numerical modeling of the ice-earth system and empirical modeling of shoreline deformation are both consistent with observed shoreline tilting in the north and with the amount and pattern of modern deformation shown by lake-level gauges. New studies of subaerial lacustrine features suggest the presence of deformed shorelines higher than those originally ascribed to the supposed horizontal Glenwood level. Finally, the Lake Michigan region as a whole appears to behave in a similar manner to other areas, both local (other Great Lakes) and regional (U.S. east coast), that have experienced major isostatic changes. Detailed sedimentological and dating studies of field sites and additional

  20. 77 FR 39638 - Safety Zone; Barbara Harder Wedding Fireworks, Lake Erie, Lake View, NY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-05

    ...-AA00 Safety Zone; Barbara Harder Wedding Fireworks, Lake Erie, Lake View, NY AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on Lake Erie, Lake View, NY. This safety zone is intended to restrict vessels from a portion of Lake Erie...

  1. Genetic diversity of lake whitefish in lakes Michigan and Huron: sampling, standardization, and research priorities

    USGS Publications Warehouse

    Stott, Wendylee; VanDeHey, Justin A.; Sloss, Brian L.

    2010-01-01

    We combined data from two laboratories to increase the spatial extent of a genetic data set for lake whitefish Coregonus clupeaformis from lakes Huron and Michigan and saw that genetic diversity was greatest between lakes, but that there was also structuring within lakes. Low diversity among stocks may be a reflection of relatively recent colonization of the Great Lakes, but other factors such as recent population fluctuation and localized stresses such as lamprey predation or heavy exploitation may also have a homogenizing effect. Our data suggested that there is asymmetrical movement of lake whitefish between Lake Huron and Lake Michigan; more genotypes associated with Lake Michigan were observed in Lake Huron. Adding additional collections to the calibrated set will allow further examination of diversity in other Great Lakes, answer questions regarding movement among lakes, and estimate contributions of stocks to commercial yields. As the picture of genetic diversity and population structure of lake whitefish in the Great Lakes region emerges, we need to develop methods to combine data types to help identify important areas for biodiversity and thus conservation. Adding genetic data to existing models will increase the precision of predictions of the impacts of new stresses and changes in existing pressures on an ecologically and commercially important species.

  2. [Characterizing chromophoric dissolved organic matter (CDOM) in Lake Honghu, Lake Donghu and Lake Liangzihu using excitation-emission matrices (EEMs) fluorescence and parallel factor analysis (PARAFAC)].

    PubMed

    Zhou, Yong-Qiang; Zhang, Yun-Lin; Niu, Cheng; Wang, Ming-Zhu

    2013-12-01

    Little is known about DOM characteristics in medium to large sized lakes located in the middle and lower reaches of Yangtze River, like Lake Honghu, Lake Donghu and Lake Liangzihu. Absorption, fluorescence and composition characteristics of chromophoric dissolved organic matter (CDOM) are presented using the absorption spectroscopy, the excitation-emission ma trices (EEMs) fluorescence and parallel factor analysis (PARAFAC) model based on the data collected in Sep-Oct. 2007 including 15, 9 and 10 samplings in Lake Honghu, Lake Donghu and Lake Liangzihu, respectively. CDOM absorption coefficient at 350 nm a(350) coefficient in Lake Honghu was significantly higher than those in Lake Donghu and Lake Liangzihu (t-test, p< 0. 001). A significant negative correlation was found between CDOM spectral slope in the wavelength range of 280-500 nm (S280-500) and a(350) (R2 =0. 781, p<0. 001). The mean value of S280-500 in Lake Honghu was significantly lower than those in Lake Donghu (t-test, pLake Liangzihu (t-test, p<0. 001). The mean value of spectral slope ratio SR in Lake Honghu was also significantly lower than those in Lake Donghu and Lake Liangzihu (t-test, p<0. 05). Two humic-like (C1, C2) and two protein-like fluorescent components (C3, C4) were identified by PARAFAC model, among which significant positive correlations were found between C1 and C2 (R2 =0. 884, p<0. 001), C3 and C4 (R2 =0. 677, p<0.001), respectively, suggesting that the sources of the two humic-like components as well as the two protein-like components were similar. However, no significant correlation has been found between those 4 fluorescent components and DOC concentration. Th e fluorescenceindices of FI255 (HIX), Fl265, FI310 (BIX) and Fl370 in Lake Donghu were all significantly higher than those in Lake Liangzihu (t-test, p <0.05) and Lake Honghu (t-test, p<0. 01), indicating that the eutrophication status in Lake Donghu was higher than Lake Honghu and Lake Liangzihu.

  3. Exploring trends, causes, and consequences of declining lipids in Lake Superior lake trout

    EPA Science Inventory

    The ability of lake trout to forage in deepwater habitats is facilitated by high lipid content, which affords buoyancy. In Lake Superior, lean lake trout historically occupied depths < 80 m, and siscowet lake trout occupied depths > 80 m. Siscowets have been known f...

  4. Great Lakes

    USGS Publications Warehouse

    Edsall, Thomas A.; Mac, Michael J.; Opler, Paul A.; Puckett Haecker, Catherine E.; Doran, Peter D.

    1998-01-01

    The Great Lakes region, as defined here, includes the Great Lakes and their drainage basins in Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, and New York. The region also includes the portions of Minnesota, Wisconsin, and the 21 northernmost counties of Illinois that lie in the Mississippi River drainage basin, outside the floodplain of the river. The region spans about 9º of latitude and 20º of longitude and lies roughly halfway between the equator and the North Pole in a lowland corridor that extends from the Gulf of Mexico to the Arctic Ocean.The Great Lakes are the most prominent natural feature of the region (Fig. 1). They have a combined surface area of about 245,000 square kilometers and are among the largest, deepest lakes in the world. They are the largest single aggregation of fresh water on the planet (excluding the polar ice caps) and are the only glacial feature on Earth visible from the surface of the moon (The Nature Conservancy 1994a).The Great Lakes moderate the region’s climate, which presently ranges from subarctic in the north to humid continental warm in the south (Fig. 2), reflecting the movement of major weather masses from the north and south (U.S. Department of the Interior 1970; Eichenlaub 1979). The lakes act as heat sinks in summer and heat sources in winter and are major reservoirs that help humidify much of the region. They also create local precipitation belts in areas where air masses are pushed across the lakes by prevailing winds, pick up moisture from the lake surface, and then drop that moisture over land on the other side of the lake. The mean annual frost-free period—a general measure of the growing-season length for plants and some cold-blooded animals—varies from 60 days at higher elevations in the north to 160 days in lakeshore areas in the south. The climate influences the general distribution of wild plants and animals in the region and also influences the activities and distribution of the human

  5. Lakes, Lagerstaetten, and Evolution

    NASA Astrophysics Data System (ADS)

    Kordesch, E. G.; Park, L. E.

    2001-12-01

    The diversity of terrestrial systems is estimated to be greater than in the marine realm. However no hard data yet exists to substantiate this claim. Ancient lacustrine deposits may preserve an exceptionally diverse fossil fauna and aid in determining continental faunal diversities. Fossils preserved in lake deposits, especially those with exceptional preservation (i.e. Konservat Lagerstaetten), may represent a dependable method for determining species diversity changes in the terrestrial environment because of their faunal completeness. Important Konservat Lagerstaetten, such as the Green River Formation (US) and Messel (Germany), both Eocene in age, are found in lake sediments and show a remarkable faunal diversity for both vertebrates and invertebrates. To date information from nearly 25 lake lagerstaetten derived from different types of lake basins from the Carboniferous to the Miocene have been collected and described. Carboniferous sites derive from the cyclothems of Midcontinent of the US while many Cenozoic sites have been described from North and South America as well as Europe and Australia. Asian sites contain fossils from the Mesozoic and Cenozoic. With this data, insight into the evolutionary processes associated with lake systems can be examined. Do lakes act as unique evolutionary crucibles in contrast to marine systems? The speciation of cichlid fishes in present-day African lakes appears to be very high and is attributed to the diversity of environments found in large rift lakes. Is this true of all ancient lakes or just large rift lakes? The longevity of a lake system may be an important factor in allowing speciation and evolutionary processes to occur; marine systems are limited only in the existence of environments as controlled by tectonics and sea level changes, on the order of tens of millions of years. Rift lakes are normally the longest lived in the millions of years. Perhaps there are only certain types of lakes in which speciation of

  6. Suspended-sediment budget, flow distribution, and lake circulation for the Fox Chain of Lakes in Lake and McHenry Counties, Illinois, 1997-99

    USGS Publications Warehouse

    Schrader, David L.; Holmes, Robert R.

    2000-01-01

    The Fox Chain of Lakes is a glacial lake system in McHenry and Lake Counties in northern Illinois and southern Wisconsin. Sedimentation and nutrient overloading have occurred in the lake system since the first dam was built (1907) in McHenry to raise water levels in the lake system. Using data collected from December 1, 1997, to June 1, 1999, suspended-sediment budgets were constructed for the most upstream lake in the system, Grass Lake, and for the lakes downstream from Grass Lake. A total of 64,900 tons of suspended sediment entered Grass Lake during the study, whereas a total of 70,600 tons of suspended sediment exited the lake, indicating a net scour of 5,700 tons of sediment. A total of 44,100 tons of suspended sediment was measured exiting the Fox Chain of Lakes at Johnsburg, whereas 85,600 tons entered the system downstream from Grass Lake. These suspended-sediment loads indicate a net deposition of 41,500 tons downstream from Grass Lake, which represents a trapping efficiency of 48.5 percent. A large amount of recreational boating takes place on the Fox Chain of Lakes during summer months, and suspended-sediment load was observed to rise from 110 tons per day to 339 tons per day during the 1999 Memorial Day weekend (May 26 ?31, 1999). Presumably, this rise was the result of the boating traffic because no other hydrologic event is known to have occurred that might have caused the rise. This study covers a relatively short period and may not represent the long-term processes of the Fox Chain of Lakes system, although the sediment transport was probably higher than an average year. The bed sediments found on the bottom of the lakes are composed of mainly fine particles in the silt-clay range. The Grass Lake sediments were characterized as black peat with an organic content of between 9 and 18 percent, and the median particle size ranged from 0.000811 to 0.0013976 inches. Other bed material samples were collected at streamflow-gaging stations on the

  7. Changing abundance of Hexagenia mayfly nymphs in western Lake Erie of the Laurentian Great Lakes: Impediments to assessment of lake recovery?

    USGS Publications Warehouse

    Schloesser, D.W.; Nalepa, T.F.

    2001-01-01

    After an absence of 40 years, mayfly nymphs of the genus Hexagenia were found in sediments of western Lake Erie of the Laurentian Great Lakes in 1993 and, by 1997, were abundant enough to meet a mayfly-density management goal (ca. 350 nymphs m—2) based on pollution-abatement programs. We sampled nymphs in western Lake Erie and Lake St. Clair, located upstream of western Lake Erie, to determine the importance of seasonal abundance and life-history characteristics of nymphs (e.g., emergence and recruitment) on density estimates relative to the mayfly-density management goal. Two types of density patterns were observed: (1) densities were relatively high in spring and gradually decreased through late summer (observed in Lake Erie and Lake St. Clair in 1997 and Lake St. Clair in 1999) and (2) densities were relatively high in spring, gradually decreased to mid summer, abruptly decreased in mid summer, and then increased between summer and late fall (Lake Erie and Lake St. Clair in 1998 and Lake Erie in 1999). Length-frequency distributions of nymphs and observations of adults indicate that the primary cause for the two density patterns was attributed to failed (first pattern) and successful (second pattern) reproduction and emergence of nymphs into adults in mid summer. Gradual declines in densities were attributed to mortality of nymphs. Our results indicate that caution should be used when evaluating progress of pollution-abatement programs based on mayfly densities because recruitment success is variable both between and within years. Additionally, the interpretation of progress toward management goals, relative to the restoration of Hexagenia populations in the Great Lakes and possibly other water bodies throughout the world, is influenced by the number of years in which consequtive collections are made.

  8. 33 CFR 162.220 - Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Hoover Dam, Lake Mead, and Lake... REGULATIONS § 162.220 Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev. (a) Lake Mead and... the axis of Hoover Dam and that portion of Lake Mohave (Colorado River) extending 4,500 feet...

  9. 33 CFR 162.220 - Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Hoover Dam, Lake Mead, and Lake... REGULATIONS § 162.220 Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev. (a) Lake Mead and... the axis of Hoover Dam and that portion of Lake Mohave (Colorado River) extending 4,500 feet...

  10. 33 CFR 162.220 - Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Hoover Dam, Lake Mead, and Lake... REGULATIONS § 162.220 Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev. (a) Lake Mead and... the axis of Hoover Dam and that portion of Lake Mohave (Colorado River) extending 4,500 feet...

  11. 33 CFR 162.220 - Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Hoover Dam, Lake Mead, and Lake... REGULATIONS § 162.220 Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev. (a) Lake Mead and... the axis of Hoover Dam and that portion of Lake Mohave (Colorado River) extending 4,500 feet...

  12. Lake Characteristics Influencing Spawning Success of Muskellunge in Northern Wisconsin Lakes

    Treesearch

    Ashley J. Rust; James S. Diana; Terry L. Margenau; Clayton J. Edwards

    2002-01-01

    We determined the physical, chemical, biological, and land use characteristics that distinguish northern Wisconsin lakes with self-sustaining populations of muskellunge Esox masquinongy from lakes where stocking is required to maintain populations. Lakes that supported self-sustaining muskellunge populations were characterized by fewer shoreline...

  13. Evaluating COSMO's lake module (FLake) for an East-African lake using a comprehensive set of lake temperature profiles

    NASA Astrophysics Data System (ADS)

    Thiery, W.; Martynov, A.; Darchambeau, F.; Demuzere, M.; van Lipzig, N.

    2012-04-01

    The African great lakes are of utmost importance for the local economy (fishing), as well as being essential to the survival of the local people. During last decades, these lakes have been changing rapidly and their evolution is a major concern. Hence, it is important to correctly represent them in regional climate models for simulations over tropical Africa. However, so far lake models have been developed and tested primarily for boreal conditions. In this study, for the first time the freshwater lake model FLake is evaluated over East-Africa, more specifically over lake Kivu. Meteorological observations from January 2003 to December 2008 from an automatic weather station in Bukavu, DRC, are used to drive the standalone version of FLake. For the evaluation, a unique dataset is used which contains over 200 temperature profiles recorded since 2002. Results show that FLake in its default configuration is very successful at reproducing both the timing and magnitude of the seasonal cycle at 5 m depth. Flake captures that this seasonality is regulated by the water vapour pressure, which constrains evaporation except during summer (JJA). A positive bias of ~1 K is attributed to the driving data, which are collected in the city and are therefore expected to mirror higher temperatures and lower wind speeds compared to the lake surface. The evaluation also showed that driving FLake with Era-Interim from the nearest pixel does only slightly deteriorate the model performance. Using forcing fields from the Canadian Regional Climate Model, version 5 (CRCM5) simulation output gives similar performance as Era-Interim. Furthermore, a drawback of FLake is that it does not account for salinity and its effect upon lake stratification, and therefore requires artificial initial conditions for both lake depth and bottom temperature in order to reproduce the correct mixing regime in lake Kivu. Further research will therefore aim at improving FLake's representation of tropical lakes.

  14. Seasonal thermal ecology of adult walleye (Sander vitreus) in Lake Huron and Lake Erie.

    PubMed

    Peat, Tyler B; Hayden, Todd A; Gutowsky, Lee F G; Vandergoot, Christopher S; Fielder, David G; Madenjian, Charles P; Murchie, Karen J; Dettmers, John M; Krueger, Charles C; Cooke, Steven J

    2015-10-01

    The purpose of this study was to characterize thermal patterns and generate occupancy models for adult walleye from lakes Erie and Huron with internally implanted biologgers coupled with a telemetry study to assess the effects of sex, fish size, diel periods, and lake. Sex, size, and diel periods had no effect on thermal occupancy of adult walleye in either lake. Thermal occupancy differed between lakes and seasons. Walleye from Lake Erie generally experienced higher temperatures throughout the spring and summer months than did walleye in Lake Huron, due to limnological differences between the lakes. Tagged walleye that remained in Saginaw Bay, Lake Huron (i.e., adjacent to the release location), as opposed to those migrating to the main basin of Lake Huron, experienced higher temperatures, and thus accumulated more thermal units (the amount of temperature units amassed over time) throughout the year. Walleye that migrated toward the southern end of Lake Huron occupied higher temperatures than those that moved toward the north. Consequently, walleye that emigrated from Saginaw Bay experienced thermal environments that were more favorable for growth as they spent more time within their thermal optimas than those that remained in Saginaw Bay. Results presented in this paper provide information on the thermal experience of wild fish in a large lake, and could be used to refine sex- and lake-specific bioenergetics models of walleye in the Great Lakes to enable the testing of ecological hypotheses. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Seasonal thermal ecology of adult walleye (Sander vitreus) in Lake Huron and Lake Erie

    USGS Publications Warehouse

    Peat, Tyler B; Hayden, Todd A.; Gutowsky, Lee F G; Vandergoot, Christopher S.; Fielder, David G.; Madenjian, Charles P.; Murchie, Karen J; Dettmers, John M.; Krueger, Charles C.; Cooke, Steven J.

    2015-01-01

    The purpose of this study was to characterize thermal patterns and generate occupancy models for adult walleye from lakes Erie and Huron with internally implanted biologgers coupled with a telemetry study to assess the effects of sex, fish size, diel periods, and lake. Sex, size, and diel periods had no effect on thermal occupancy of adult walleye in either lake. Thermal occupancy differed between lakes and seasons. Walleye from Lake Erie generally experienced higher temperatures throughout the spring and summer months than did walleye in Lake Huron, due to limnological differences between the lakes. Tagged walleye that remained in Saginaw Bay, Lake Huron (i.e., adjacent to the release location), as opposed to those migrating to the main basin of Lake Huron, experienced higher temperatures, and thus accumulated more thermal units (the amount of temperature units amassed over time) throughout the year. Walleye that migrated toward the southern end of Lake Huron occupied higher temperatures than those that moved toward the north. Consequently, walleye that emigrated from Saginaw Bay experienced thermal environments that were more favorable for growth as they spent more time within their thermal optimas than those that remained in Saginaw Bay. Results presented in this paper provide information on the thermal experience of wild fish in a large lake, and could be used to refine sex- and lake-specific bioenergetics models of walleye in the Great Lakes to enable the testing of ecological hypotheses.

  16. Hydrology of Indiana lakes

    USGS Publications Warehouse

    Perrey, Joseph Irving; Corbett, Don Melvin

    1956-01-01

    The stabilization of lake levels often requires the construction of outlet control structures. A detailed study of past lake-level elevations and other hydologic date is necessary to establish a level that can be maintained and to determine the means necessary for maintaining the established level. Detailed lake-level records for 28 lakes are included in the report, and records for over 100 other lakes data are available in the U.S. Geological Survey Office, Indianapolis, Ind. Evaporation data from the four Class A evaporation station of the U. S. Weather Bureau have been compiled in this report. A table showing the established legal lake level and related data is included.

  17. First evidence of successful natural reproduction by planted lake trout in Lake Huron

    USGS Publications Warehouse

    Nester, Robert T.; Poe, Thomas P.

    1984-01-01

    Twenty-two lake trout (Salvelinus namaycush) swim-up fry, 24-27 mm long, were captured with emergent fry traps and a tow net in northwestern Lake Huron on a small nearshore reef off Alpena, Michigan, between May 10 and June 1, 1982. These catches represent the first evidence of successful production of swim-up fry by planted, hatchery-reared lake trout in Lake Huron since the lake trout rehabilitation program began in 1973.

  18. Estimation of lake water - groundwater interactions in meromictic mining lakes by modelling isotope signatures of lake water.

    PubMed

    Seebach, Anne; Dietz, Severine; Lessmann, Dieter; Knoeller, Kay

    2008-03-01

    A method is presented to assess lake water-groundwater interactions by modelling isotope signatures of lake water using meteorological parameters and field data. The modelling of delta(18)O and deltaD variations offers information about the groundwater influx into a meromictic Lusatian mining lake. Therefore, a water balance model is combined with an isotope water balance model to estimate analogies between simulated and measured isotope signatures within the lake water body. The model is operated with different evaporation rates to predict delta(18)O and deltaD values in a lake that is only controlled by weather conditions with neither groundwater inflow nor outflow. Comparisons between modelled and measured isotope values show whether the lake is fed by the groundwater or not. Furthermore, our investigations show that an adaptation of the Craig and Gordon model [H. Craig, L.I. Gordon. Deuterium and oxygen-18 variations in the ocean and the marine atmosphere. In Stable Isotopes in Oceanographic Studies and Paleotemperature, Spoleto, E. Tongiorgi (Ed.), pp. 9-130, Consiglio Nazionale delle Ricerche, Laboratorio di Geologia Nucleare, Pisa (1965).] to specific conditions in temperate regions seems necessary.

  19. 75 FR 13232 - Safety Zone; Lake Mead Intake Construction, Lake Mead, Boulder City, NV

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-19

    ...-AA00 Safety Zone; Lake Mead Intake Construction, Lake Mead, Boulder City, NV AGENCY: Coast Guard, DHS... waters of Lake Mead in support of the construction project for Lake Mead's Intake 3. This safety zone is... for the placement of an Intake Pipe from Lake Mead throughout 2010. This safety zone is necessary to...

  20. 78 FR 17869 - Safety Zone; Desert Storm Shootout; Lake Havasu, Lake Havasu City, AZ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-25

    ...-AA00 Safety Zone; Desert Storm Shootout; Lake Havasu, Lake Havasu City, AZ AGENCY: Coast Guard, DHS... navigable waters of the Colorado River in Lake Havasu, Lake Havasu City, Arizona in support of the Desert... Coast Guard to establish safety zones (33 U.S.C 1221 et seq.). Lake Racer LLC is sponsoring the Desert...

  1. Bioturbation enhances the aerobic respiration of lake sediments in warming lakes.

    PubMed

    Baranov, Viktor; Lewandowski, Jörg; Krause, Stefan

    2016-08-01

    While lakes occupy less than 2% of the total surface of the Earth, they play a substantial role in global biogeochemical cycles. For instance, shallow lakes are important sites of carbon metabolism. Aerobic respiration is one of the important drivers of the carbon metabolism in lakes. In this context, bioturbation impacts of benthic animals (biological reworking of sediment matrix and ventilation of the sediment) on sediment aerobic respiration have previously been underestimated. Biological activity is likely to change over the course of a year due to seasonal changes of water temperatures. This study uses microcosm experiments to investigate how the impact of bioturbation (by Diptera, Chironomidae larvae) on lake sediment respiration changes when temperatures increase. While at 5°C, respiration in sediments with and without chironomids did not differ, at 30°C sediment respiration in microcosms with 2000 chironomids per m(2) was 4.9 times higher than in uninhabited sediments. Our results indicate that lake water temperature increases could significantly enhance lake sediment respiration, which allows us to better understand seasonal changes in lake respiration and carbon metabolism as well as the potential impacts of global warming. © 2016 The Authors.

  2. Bioturbation enhances the aerobic respiration of lake sediments in warming lakes

    PubMed Central

    Krause, Stefan

    2016-01-01

    While lakes occupy less than 2% of the total surface of the Earth, they play a substantial role in global biogeochemical cycles. For instance, shallow lakes are important sites of carbon metabolism. Aerobic respiration is one of the important drivers of the carbon metabolism in lakes. In this context, bioturbation impacts of benthic animals (biological reworking of sediment matrix and ventilation of the sediment) on sediment aerobic respiration have previously been underestimated. Biological activity is likely to change over the course of a year due to seasonal changes of water temperatures. This study uses microcosm experiments to investigate how the impact of bioturbation (by Diptera, Chironomidae larvae) on lake sediment respiration changes when temperatures increase. While at 5°C, respiration in sediments with and without chironomids did not differ, at 30°C sediment respiration in microcosms with 2000 chironomids per m2 was 4.9 times higher than in uninhabited sediments. Our results indicate that lake water temperature increases could significantly enhance lake sediment respiration, which allows us to better understand seasonal changes in lake respiration and carbon metabolism as well as the potential impacts of global warming. PMID:27484649

  3. Lake Sturgeon, Acipenser fulvescens, movements in Rainy Lake, Minnesota and Ontario

    USGS Publications Warehouse

    Adams, W.E.; Kallemeyn, L.W.; Willis, D.W.

    2006-01-01

    Rainy Lake, Minnesota-Ontario, contains a native population of Lake Sturgeon (Acipenser fulvescens) that has gone largely unstudied. The objective of this descriptive study was to summarize generalized Lake Sturgeon movement patterns through the use of biotelemetry. Telemetry data reinforced the high utilization of the Squirrel Falls geographic location by Lake Sturgeon, with 37% of the re-locations occurring in that area. Other spring aggregations occurred in areas associated with Kettle Falls, the Pipestone River, and the Rat River, which could indicate spawning activity. Movement of Lake Sturgeon between the Seine River and the South Arm of Rainy Lake indicates the likelihood of one integrated population on the east end of the South Arm. The lack of re-locations in the Seine River during the months of September and October may have been due to Lake Sturgeon moving into deeper water areas of the Seine River and out of the range of radio telemetry gear or simply moving back into the South Arm. Due to the movements between Minnesota and Ontario, coordination of management efforts among provincial, state, and federal agencies will be important.

  4. Stratigraphic framework and lake level history of Lake Kivu, East African Rift

    NASA Astrophysics Data System (ADS)

    Wood, Douglas A.; Scholz, Christopher A.

    2017-10-01

    Sediment cores and seismic reflection data acquired from the eastern basin of Lake Kivu, Rwanda reveal extensive limnologic variations due to changes in regional climate and basin structure. The eastern basin of the lake contains a sedimentary wedge which is > 1.5 km in thickness on its western side, and basal sediments are estimated to be at least 1.5 million years old. Sediments are likely to be thicker and older than this in the northern, Congolese basin of the lake. Above the ∼300 m iosbath only a thin layer of Holocene sediments are observed indication that this may have been the lake's high stand prior to that time. There are at least three erosional unconformities interpreted as desiccation or near-desiccation events which are estimated to have occurred at ∼475 ka, ∼100 ka, and ∼20 ka; the two most recent of these low stages likely developed during the African Megadrought and Last Glacial Maximum (LGM) periods. Following the LGM, the water levels rose to form a ∼100 m deep lake with its surface ∼370 m below the current lake level. The lake remained near that level for several thousand years and during this time the Virunga Volcanic Province expanded. At ∼12.2 ka a change to wetter climate conditions rapidly filled the lake to spill out of the Bukavu Bay basin southward toward Lake Tanganyika. Tephra sampled from the cores show that there have been at least 24 large local volcanic events since the early Holocene lake transgression.

  5. Hydrology of Crater, East and Davis Lakes, Oregon; with section on Chemistry of the Lakes

    USGS Publications Warehouse

    Phillips, Kenneth N.; Van Denburgh, A.S.

    1968-01-01

    Crater, East, and Davis Lakes are small bodies of fresh water that occupy topographically closed basins in Holocene volcanic terrane. Because the annual water supply exceeds annual evaporation, water must be lost by seepage from each lake. The seepage rates vary widely both in volume and in percentage of the total water supply. Crater Lake loses about 89 cfs (cubic feet per second), equivalent to about 72 percent of its average annual supply. East Lake loses about 2.3 cfs, or about 44 percent of its estimated supply. Davis Lake seepage varies greatly with lake level, but the average loss is about 150 cfs, more than 90 percent of its total supply. The destination of the seepage loss is not definitely known for any of the lakes. An approximate water budget was computed for stationary level for each lake, by using estimates 'by the writer to supplement the hydrologic data available. The three lake waters are dilute. Crater Lake contains about 80 ppm, (parts per million) of dissolved solids---mostly silica, sodium, and bicarbonate, and lesser amounts of calcium, sulfate, and chloride. Much of the dissolved-solids content of Crater Lake---especially the sulfate and chloride---may be related to fumarole and thermal-spring activity that presumably followed the collapse of Mount Mazama. Although Grater Lake loses an estimated 7,000 tons of its 1.5million-ton salt content each year by leakage, the chemical character of the lake did not change appreciably between 1912 and 1964. East Lake contains 200 ppm of dissolved solids, which includes major proportions of calcium, sodium, bicarbonate, and sulfate, but almost no chloride. The lake apparently receives much of its dissolved solids from subsurface thermal springs. Annual solute loss from East Lake by leakage is about 450 tons, or 3 percent of the lake's 15,000-ton estimated solute content. Davis Lake contains only 48 ppm of dissolved solids, much of which is silica and bicarbonate; chloride is almost completely absent

  6. 76 FR 2579 - Safety Zone; Lake Mead Intake Construction, Lake Mead, Boulder City, NV

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-14

    ...-AA00 Safety Zone; Lake Mead Intake Construction, Lake Mead, Boulder City, NV AGENCY: Coast Guard, DHS... waters of Lake Mead in support of the construction project for Lake Mead's Intake 3 during the first 6... blasting operations for the placement of a water intake pipe in Lake Mead during the first 6 months of 2011...

  7. Evaluation of methods to estimate lake herring spawner abundance in Lake Superior

    USGS Publications Warehouse

    Yule, D.L.; Stockwell, J.D.; Cholwek, G.A.; Evrard, L.M.; Schram, S.; Seider, M.; Symbal, M.

    2006-01-01

    Historically, commercial fishers harvested Lake Superior lake herring Coregonus artedi for their flesh, but recently operators have targeted lake herring for roe. Because no surveys have estimated spawning female abundance, direct estimates of fishing mortality are lacking. The primary objective of this study was to determine the feasibility of using acoustic techniques in combination with midwater trawling to estimate spawning female lake herring densities in a Lake Superior statistical grid (i.e., a 10′ latitude × 10′ longitude area over which annual commercial harvest statistics are compiled). Midwater trawling showed that mature female lake herring were largely pelagic during the night in late November, accounting for 94.5% of all fish caught exceeding 250 mm total length. When calculating acoustic estimates of mature female lake herring, we excluded backscattering from smaller pelagic fishes like immature lake herring and rainbow smelt Osmerus mordax by applying an empirically derived threshold of −35.6 dB. We estimated the average density of mature females in statistical grid 1409 at 13.3 fish/ha and the total number of spawning females at 227,600 (95% confidence interval = 172,500–282,700). Using information on mature female densities, size structure, and fecundity, we estimate that females deposited 3.027 billion (109) eggs in grid 1409 (95% confidence interval = 2.356–3.778 billion). The relative estimation error of the mature female density estimate derived using a geostatistical model—based approach was low (12.3%), suggesting that the employed method was robust. Fishing mortality rates of all mature females and their eggs were estimated at 2.3% and 3.8%, respectively. The techniques described for enumerating spawning female lake herring could be used to develop a more accurate stock–recruitment model for Lake Superior lake herring.

  8. Lake Chad, Chad, Africa

    NASA Image and Video Library

    1990-04-29

    Africa's Lake Chad where the borders of Chad, Niger, Nigeria and Cameroon merge (13.0N, 14.0E) has been undergoing change for the past 25 to 30 years when it was first noticed that the lake is drying up. Since then, astronauts have been photographing it on a regular basis to record the diminishing lake bed. This lake was once the aproximate size of Lake Erie but is now only about half that size and is still receeding.

  9. Water-quality and lake-stage data for Wisconsin lakes, water year 2014

    USGS Publications Warehouse

    Manteufel, S. Bridgett; Robertson, Dale M.

    2017-05-25

    IntroductionThe U.S. Geological Survey (USGS), in cooperation with local and other agencies, collects data at selected lakes throughout Wisconsin. These data, accumulated over many years, provide a database for developing an improved understanding of the water quality of lakes. To make these data available to interested parties outside the USGS, the data are published annually in this report series. The locations of water-quality and lake-stage stations in Wisconsin for water year 2014 are shown in figure 1. A water year is the 12-month period from October 1 through September 30. It is designated by the calendar year in which it ends. Thus, the periodOctober 1, 2013, through September 30, 2014, is called “water year 2014.”The purpose of this report is to provide information about the chemical and physical characteristics of Wisconsin lakes. Data that have been collected at specific lakes, and information to aid in the interpretation of those data, are included in this report. Data collected include measurements of in-lake water quality and lake stage. Time series of Secchi depths, surface total phosphorus, and chlorophyll a concentrations collected during nonfrozen periods are included for many lakes. Graphs of vertical profiles of temperature, dissolved oxygen, pH, and specific conductance are included for sites where these parameters were measured. Descriptive information for each lake includes the location of the lake, area of the lake’s watershed, period for which data are available, revisions to previously published records, and pertinent remarks. Additional data, such as streamflow and water quality in tributary and outlet streams of some of the lakes, are published online at http://nwis.waterdata.usgs.gov/wi/nwis.Water-resources data, including stage and discharge data at most streamflow-gaging stations, are available online. The Wisconsin Water Science Center’s home page is at https://www.usgs.gov/centers/wisconsin-water-science-center. Information

  10. Applying ethical and legal principles to new technology: the University of Auckland Faculty of Medical and Health Sciences' policy 'Taking and Sharing Images of Patients.'

    PubMed

    Jonas, Monique; Malpas, Phillipa; Kersey, Kate; Merry, Alan; Bagg, Warwick

    2017-01-27

    To develop a policy governing the taking and sharing of photographic and radiological images by medical students. The Rules of the Health Information Privacy Code 1994 and the Code of Health and Disability Services Consumers' Rights were applied to the taking, storing and sharing of photographic and radiological images by medical students. Stakeholders, including clinicians, medical students, lawyers at district health boards in the Auckland region, the Office of the Privacy Commissioner and the Health and Disability Commissioner were consulted and their recommendations incorporated. The policy 'Taking and Sharing Images of Patients' sets expectations of students in relation to: photographs taken for the purpose of providing care; photographs taken for educational or professional practice purposes and photographic or radiological images used for educational or professional practice purposes. In addition, it prohibits students from uploading images of patients onto image-sharing apps such as Figure 1. The policy has since been extended to apply to all students at the Faculty of Medical and Health Sciences at the University of Auckland. Technology-driven evolutions in practice necessitate regular review to ensure compliance with existing legal regulations and ethical frameworks. This policy offers a starting point for healthcare providers to review their own policies and practice, with a view to ensuring that patients' trust in the treatment that their health information receives is upheld.

  11. Helminths in an intensively stocked population of lake trout, Salvelinus namaycush, from Lake Huron

    USGS Publications Warehouse

    Muzzall, Patrick M.; Bowen, Charles A.

    2000-01-01

    Eighty stocked lake trout Salvelinus namaycush (Salmonidae), collected from 2 locations in Lake Huron in May 1995, were examined for parasites. The parasite fauna of this top predator in Lake Huron was characterized by only 6 helminth species. Echinorhynchus salmonis infected all lake trout with a mean intensity of 163.9. The intensity of this acanthocephalan species significantly increased with host length and weight. Eubothrium salvelini infected 78 lake trout with a maximum number of 81 scoleces counted. Diplostomum sp., Cyathocephalus truncatus, Capillaria salvelini, and Neoechinorhynchus sp. infrequently infected lake trout. The low parasite species richness in these lake trout is believed to be due to their large size at stocking and to the loss of historical enzootic host-parasite relationships that followed the absence of this fish species in Lake Huron for 26 yr.

  12. Glaciers, Glacial lakes and Glacial Lake Outburst Floods in the Koshi Basin

    NASA Astrophysics Data System (ADS)

    Shrestha, F.; Gao, X.; Khanal, N. R.; Maharjan, S. B.; Bajracharya, S. R.; Shrestha, R. B.; Lizong, W.; Mool, P. K.

    2016-12-01

    Glacier is a vital water resources for mountain communities. Recession in glacier area either increased the glacial lake size or develop a new lake. The consequences of these changes in lake has become one of the major issue in the management of GLOF risk. This paper presents the distribution of, and changes in, glaciers, glacial lakes in the Koshi basin and also looks at past GLOF events that have occurred in the basin and their distance of impact. Data on the number of glaciers and glacial lakes and their areas were generated for the years 1977, 1990, 2000, and 2010 using Landsat images. The study revealed that there were a total of 845 glaciers (Nepal side) and 2,168 glacial lakes (Nepal and China side) with a total area of 1,103 km2 and 127.608 km2 in 2010. The number of glacier increased by 15% (109) and area decreased by 26% (396 km2) over 33 years. In case of glacier lakes, the number and area increased from 1,160 to 2,168 and from 94.444 km2 to 127.608 km2 during 33 years with an overall growth rates of 86.9% and 35.1%. A large number of glacial lakes are small in size (≤ 0.1 km2). End moraine dammed lakes with area ≥ 0.1 km2 were selected to analyse the change characteristics of glacial lakes. The results show that there were 134 lakes ≥ 0.1 km2 in 2010; these lakes had a total area of 43.06 km2 in 1997, increased to 64.35 km2 in 2010. The distribution of lakes on the north side of the Himalayas (in China) was three times higher than on the south side of the Himalayas (in Nepal). Comparing the mean growth rate in area and length for the 33 years, the growth rate on the north side was found to be a little slower than that on the south side. This relationship did not hold true for length change in the different periods. The study identified 42 rapidly growing large lakes that are dangerous in terms of GLOF risk. In the past, 18 GLOF events have been reported. The downstream distance impacted by those events was up to 90 km. Among them, 13 GLOF events

  13. Lake Michigan lake trout PCB model forecast post audit (oral presentation)

    EPA Science Inventory

    Scenario forecasts for total PCBs in Lake Michigan (LM) lake trout were conducted using the linked LM2-Toxics and LM Food Chain models, supported by a suite of additional LM models. Efforts were conducted under the Lake Michigan Mass Balance Study and the post audit represents an...

  14. Simulating Lake-Groundwater Interactions During Decadal Climate Cycles: Accounting For Variable Lake Area In The Watershed

    NASA Astrophysics Data System (ADS)

    Virdi, M. L.; Lee, T. M.

    2009-12-01

    The volume and extent of a lake within the topo-bathymetry of a watershed can change substantially during wetter and drier climate cycles, altering the interaction of the lake with the groundwater flow system. Lake Starr and other seepage lakes in the permeable sandhills of central Florida are vulnerable to climate changes as they rely exclusively on rainfall and groundwater for inflows in a setting where annual rainfall and recharge vary widely. The groundwater inflow typically arrives from a small catchment area bordering the lake. The sinkhole origin of these lakes combined with groundwater pumping from underlying aquifers further complicate groundwater interactions. Understanding the lake-groundwater interactions and their effects on lake stage over multi-decadal climate cycles is needed to manage groundwater pumping and public expectation about future lake levels. The interdependence between climate, recharge, changing lake area and the groundwater catchment pose unique challenges to simulating lake-groundwater interactions. During the 10-year study period, Lake Starr stage fluctuated more than 13 feet and the lake surface area receded and expanded from 96 acres to 148 acres over drier and wetter years that included hurricanes, two El Nino events and a La Nina event. The recently developed Unsaturated Zone Flow (UZF1) and Lake (LAK7) packages for MODFLOW-2005 were used to simulate the changing lake sizes and the extent of the groundwater catchment contributing flow to the lake. The lake area was discretized to occupy the largest surface area at the highest observed stage and then allowed to change size. Lake cells convert to land cells and receive infiltration as receding lake area exposes the underlying unsaturated zone to rainfall and recharge. The unique model conceptualization also made it possible to capture the dynamic size of the groundwater catchment contributing to lake inflows, as the surface area and volume of the lake changed during the study

  15. Lake Granbury and Lake Whitney Assessment Initiative Final Scientific/Technical Report Summary

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harris, B. L.; Roelke, Daniel; Brooks, Bryan

    A team of Texas AgriLife Research, Baylor University and University of Texas at Arlington researchers studied the biology and ecology of Prymnesium parvum (golden algae) in Texas lakes using a three-fold approach that involved system-wide monitoring, experimentation at the microcosm and mesocosm scales, and mathematical modeling. The following are conclusions, to date, regarding this organism's ecology and potential strategies for mitigation of blooms by this organism. In-lake monitoring revealed that golden algae are present throughout the year, even in lakes where blooms do not occur. Compilation of our field monitoring data with data collected by Texas Parks and Wildlife andmore » Brazos River Authority (a period spanning a decade) revealed that inflow and salinity variables affect bloom formations. Thresholds for algae populations vary per lake, likely due to adaptations to local conditions, and also to variations in lake-basin morphometry, especially the presence of coves that may serve as hydraulic storage zones for P. parvum populations. More specifically, our in-lake monitoring showed that the highly toxic bloom that occurred in Lake Granbury in the winter of 2006/2007 was eliminated by increased river inflow events. The bloom was flushed from the system. The lower salinities that resulted contributed to golden algae not blooming in the following years. However, flushing is not an absolute requirement for bloom termination. Laboratory experiments have shown that growth of golden algae can occur at salinities ~1-2 psu but only when temperatures are also low. This helps to explain why blooms are possible during winter months in Texas lakes. Our in-lake experiments in Lake Whitney and Lake Waco, as well as our laboratory experiments, revealed that cyanobacteria, or some other bacteria capable of producing algicides, were able to prevent golden algae from blooming. Identification of this organism is a high priority as it may be a key to managing golden algae

  16. Water balance of a lake with floodplain buffering: Lake Tana, Blue Nile Basin, Ethiopia

    NASA Astrophysics Data System (ADS)

    Dessie, Mekete; Verhoest, Niko E. C.; Pauwels, Valentijn R. N.; Adgo, Enyew; Deckers, Jozef; Poesen, Jean; Nyssen, Jan

    2015-03-01

    Lakes are very important components of the earth's hydrological cycle, providing a variety of services for humans and ecosystem functioning. For a sustainable use of lakes, a substantial body of knowledge on their water balance is vital. We present here a detailed daily water balance analysis for Lake Tana, the largest lake in Ethiopia and the source of the Blue Nile. Rainfall on the lake is determined by Thiessen polygon procedure, open water evaporation is estimated by the Penman-combination equation and observed inflows for the gauged catchments as well as outflow data at the two lake outlets are directly used. Runoff from ungauged catchments is estimated using a simple rainfall-runoff model and runoff coefficients. Hillslope catchments and floodplains are treated separately, which makes this study unique compared to previous water balance studies. Impact of the floodplain on the lake water balance is analyzed by conducting scenario-based studies. We found an average yearly abstraction of 420 × 106 m3 or 6% of river inflows to the lake by the floodplain in 2012 and 2013. Nearly 60% of the inflow to the lake is from the Gilgel Abay River. Simulated lake levels compare well with the observed lake levels (R2 = 0.95) and the water balance can be closed with a closure error of 82 mm/year (3.5% of the total lake inflow). This study demonstrates the importance of floodplains and their influence on the water balance of the lake and the need of incorporating the effects of floodplains and water abstraction for irrigation to improve predictions.

  17. Morphological variation of siscowet lake trout in Lake Superior

    USGS Publications Warehouse

    Bronte, C.R.; Moore, S.A.

    2007-01-01

    Historically, Lake Superior has contained many morphologically distinct forms of the lake trout Salvelinus namaycush that have occupied specific depths and locations and spawned at specific times of the year. Today, as was probably the case historically, the siscowet morphotype is the most abundant. Recent interest in harvesting siscowets to extract oil containing omega-3 fatty acids will require additional knowledge of the biology and stock structure of these lightly exploited populations. The objective of this study was to determine whether shape differences exist among siscowet populations across Lake Superior and whether these shape differences can be used to infer stock structure. Morphometric analysis (truss protocol) was used to differentiate among siscowets sampled from 23 locations in Lake Superior. We analyzed 31 distance measurements among 14 anatomical landmarks taken from digital images of fish recorded in the field. Cluster analysis of size-corrected data separated fish into three geographic groups: The Isle Royale, eastern (Michigan), and western regions (Michigan). Finer scales of stock structure were also suggested. Discriminant function analysis demonstrated that head measurements contributed to most of the observed variation. Cross-validation classification rates indicated that 67–71% of individual fish were correctly classified to their region of capture. This is the first study to present shape differences associated with location within a lake trout morphotype in Lake Superior.

  18. Geophysical investigation of sentinel lakes in Lake, Seminole, Orange, and Volusia Counties, Florida

    USGS Publications Warehouse

    Reich, Christopher; Flocks, James; Davis, Jeffrey

    2012-01-01

    This study was initiated in cooperation with the St. Johns River Water Management District (SJRWMD) to investigate groundwater and surface-water interaction in designated sentinel lakes in central Florida. Sentinel lakes are a SJRWMD established set of priority water bodies (lakes) for which minimum flows and levels (MFLs) are determined. Understanding both the structure and lithology beneath these lakes can ultimately lead to a better understanding of the MFLs and why water levels fluctuate in certain lakes more so than in other lakes. These sentinel lakes have become important water bodies to use as water-fluctuation indicators in the SJRWMD Minimum Flows and Levels program and will be used to define long-term hydrologic and ecologic performance measures. Geologic control on lake hydrology remains poorly understood in this study area. Therefore, the U.S. Geological Survey investigated 16 of the 21 water bodies on the SJRWMD priority list. Geologic information was obtained by the tandem use of high-resolution seismic profiling (HRSP) and direct-current (DC) resistivity profiling to isolate both the geologic framework (structure) and composition (lithology). Previous HRSP surveys from various lakes in the study area have been successful in identifying karst features, such as subsidence sinkholes. However, by using this method only, it is difficult to image highly irregular or chaotic surfaces, such as collapse sinkholes. Resistivity profiling was used to complement HRSP by detecting porosity change within fractured or collapsed structures and increase the ability to fully characterize the subsurface. Lake Saunders (Lake County) is an example of a lake composed of a series of north-south-trending sinkholes that have joined to form one lake body. HRSP shows surface depressions and deformation in the substrate. Resistivity data likewise show areas in the southern part of the lake where resistivity shifts abruptly from approximately 400 ohm meters (ohm-m) along the

  19. Mercury accumulation in yellow perch in Wisconsin seepage lakes: Relation to lake characteristics

    USGS Publications Warehouse

    Cope, W.G.; Wiener, J.G.; Rada, R.G.

    1990-01-01

    We studied relations between lacustrine characteristics and the total mercury (Hg) content of calendar age-2 yellow perch (Perca flavescens) in 10 seepage lakes in north-central Wisconsin. Mean concentrations and burdens (masses) of Hg in whole perch varied widely among lakes, were negatively correlated with lake pH and were positively correlated with total Hg concentration in surficial profundal sediment. Approximately 80 to 90% of the variation in Hg concentration and burden in whole perch was explained with multiple regressions containing two independent variables: either lake pH or alkalinity, and Hg concentration in surficial sediment. Variation among lakes in the Hg concentration in yellow perch was unrelated to their relative rates of growth. The mean concentration of Hg in axial muscle tissue of age-5 walleyes (Stizostedion vitreum vitreum) from five of the study lakes was highly correlated with the mean concentration in whole age-2 perch in the same lakes. We hypothesized that the high Hg concentrations often seen in piscivorous fish in low-alkalinity lakes (relative to high-alkalinity lakes) is at least partly due to a greater dietary intake of Hg in such waters. Furthermore, the analysis of small yellow perch—the preferred prey of adult walleyes and an important forage species for many predatory fishes in the north-central United States—may be an effective approach to assessing Hg bioavailability in the region's lakes.

  20. Estimate of net trophic transfer efficiency of PCBs to Lake Michigan lake trout from their prey

    USGS Publications Warehouse

    Madenjian, Charles P.; Hesselberg, Robert J.; DeSorcie, Timothy J.; Schmidt, Larry J.; Stedman, Ralph M.; Quintal, Richard T.; Begnoche, Linda J.; Passino-Reader, Dora R.

    1998-01-01

    Most of the polychlorinated biphenyl (PCB) body burden accumulated by lake trout (Salvelinus namaycush) from the Laurentian Great Lakes is from their food. We used diet information, PCB determinations in both lake trout and their prey, and bioenergetics modeling to estimate the efficiency with which Lake Michigan lake trout retain PCBs from their food. Our estimates were the most reliable estimates to date because (a) the lake trout and prey fish sampled during our study were all from the same vicinity of the lake, (b) detailed measurements were made on the PCB concentrations of both lake trout and prey fish over wide ranges in fish size, and (c) lake trout diet was analyzed in detail over a wide range of lake trout size. Our estimates of net trophic transfer efficiency of PCBs to lake trout from their prey averaged from 0.73 to 0.89 for lake trout between the ages of 5 and 10 years old. There was no evidence of an upward or downward trend in our estimates of net trophic transfer efficiency for lake trout between the ages of 5 and 10 years old, and therefore this efficiency appeared to be constant over the duration of the lake trout's adult life in the lake. On the basis of our estimtes, lake trout retained 80% of the PCBs that are contained within their food.

  1. Great Lakes Literacy Principles

    NASA Astrophysics Data System (ADS)

    Fortner, Rosanne W.; Manzo, Lyndsey

    2011-03-01

    Lakes Superior, Huron, Michigan, Ontario, and Erie together form North America's Great Lakes, a region that contains 20% of the world's fresh surface water and is home to roughly one quarter of the U.S. population (Figure 1). Supporting a $4 billion sport fishing industry, plus $16 billion annually in boating, 1.5 million U.S. jobs, and $62 billion in annual wages directly, the Great Lakes form the backbone of a regional economy that is vital to the United States as a whole (see http://www.miseagrant.umich.edu/downloads/economy/11-708-Great-Lakes-Jobs.pdf). Yet the grandeur and importance of this freshwater resource are little understood, not only by people in the rest of the country but also by many in the region itself. To help address this lack of knowledge, the Centers for Ocean Sciences Education Excellence (COSEE) Great Lakes, supported by the U.S. National Science Foundation and the National Oceanic and Atmospheric Administration, developed literacy principles for the Great Lakes to serve as a guide for education of students and the public. These “Great Lakes Literacy Principles” represent an understanding of the Great Lakes' influences on society and society's influences on the Great Lakes.

  2. Climate-driven changes in grassland vegetation, snow cover, and lake water of the Qinghai Lake basin

    NASA Astrophysics Data System (ADS)

    Wang, Xuelu; Liang, Tiangang; Xie, Hongjie; Huang, Xiaodong; Lin, Huilong

    2016-07-01

    Qinghai Lake basin and the lake have undergone significant changes in recent decades. We examine MODIS-derived grassland vegetation and snow cover of the Qinghai Lake basin and their relations with climate parameters during 2001 to 2010. Results show: (1) temperature and precipitation of the Qinghai Lake basin increased while evaporation decreased; (2) most of the grassland areas improved due to increased temperature and growing season precipitation; (3) weak relations between snow cover and precipitation/vegetation; (4) a significantly negative correlation between lake area and temperature (r=-0.9, p<0.05) and (5) a positive relation between lake level (lake-level difference) and temperature (precipitation). Compared with Namco Lake (located in the inner Tibetan Plateau) where the primary water source of lake level increases was the accelerated melt of glacier/perennial snow cover in the lake basin, for the Qinghai Lake, however, it was the increased precipitation. Increased precipitation explained the improvement of vegetation cover in the Qinghai Lake basin, while accelerated melt of glacier/perennial snow cover was responsible for the degradation of vegetation cover in Namco Lake basin. These results suggest different responses to the similar warming climate: improved (degraded) ecological condition and productive capacity of the Qinghai Lake basin (Namco Lake basin).

  3. Lake whitefish and Diporeia spp. in the Great lakes: an overview

    USGS Publications Warehouse

    Nalepa, Thomas F.; Mohr, Lloyd C.; Henderson, Bryan A.; Madenjian, Charles P.; Schneeberger, Philip J.

    2005-01-01

    Because of growing concern in the Great Lakes over declines in abundance and growth of lake whitefish (Coregonus clupeaformis) and declines in abundance of the benthic amphipod Diporeia spp., a workshop was held to examine past and current trends, to explore trophic links, and to discuss the latest research results and needs. The workshop was divided into sessions on the status of populations in each of the lakes, bioenergetics and trophic dynamics, and exploitation and management. Abundance, growth, and condition of whitefish populations in Lakes Superior and Erie are stable and within the range of historical means, but these variables are declining in Lakes Michigan and Ontario and parts of Lake Huron. The loss of Diporeia spp., a major food item of whitefish, has been a factor in observed declines, particularly in Lake Ontario, but density-dependent factors also likely played a role in Lakes Michigan and Huron. The loss of Diporeia spp. is temporally linked to the introduction and proliferation of dreissenid mussels, but a direct cause for the negative response of Diporeia spp. has not been established. Given changes in whitefish populations, age-structured models need to be re-evaluated. Other whitefish research needs to include a better understanding of what environmental conditions lead to strong year-classes, improved aging techniques, and better information on individual population (stock) structure. Further collaborations between assessment biologists and researchers studying the lower food web would enhance an understanding of links between trophic levels.

  4. An exploratory study of the health harms and utilisation of health services of frequent legal high users under the interim regulated legal high market in central Auckland.

    PubMed

    Wilkins, Chris; Prasad, Jitesh; Wong, K C; Rychert, Marta; Graydon-Guy, Thomas

    2016-03-11

    To explore health problems and the accessing of health services by frequent legal high users under an interim regulated legal market in central Auckland. Frequent legal high users (monthly+) were recruited from outside eight randomly-selected, licensed, legal high stores in central Auckland from 23 April-7 May, 2014. Eligible participants were emailed a unique invitation to complete an on-line survey; 105 completed the survey. Twenty-seven percent had suffered mental illness during their lifetimes. Eighty percent used synthetic cannabinoids (SC), and 20% 'party pills'. Forty-seven percent of SC users used daily or more often. Other drugs used included alcohol (80%), cannabis (59%), 'ecstasy' (18%) and methamphetamine (15%). Fifty-eight percent of SC users were classified as SC dependent. The most common problems reported from SC use were: insomnia (29%); 'vomiting/nausea' (25%); 'short temper/agitation' (21%); 'anxiety' (21%); 'strange thoughts' (16%); and 'heart palpitations' (14%). The health services most commonly accessed by SC users were: a 'doctor/GP' (9%); 'counsellor' (9%); 'DrugHelp/MethHelp' websites (7%); 'Alcohol & Drug Helpline' (4%); 'ambulance' (3%); 'A&E' (3%); and hospitalisation (3%). Frequent use of interim licensed SC products was associated with health problems, including dependency. Further research is required to determine the health risks of these products.

  5. Lake trout (Salvelinus namaycush) populations in Lake Superior and their restoration in 1959-1993

    USGS Publications Warehouse

    Hansen, Michael J.; Peck, James W.; Schorfhaar, Richard G.; Selgeby, James H.; Schreiner, Donald R.; Schram, Stephen T.; Swanson, Bruce L.; MacCallum, Wayne R.; Burnham-Curtis, Mary K.; Curtis, Gary L.; Heinrich, John W.; Young, Robert J.

    1995-01-01

    Naturally-reproducing populations of lake trout (Salvelinus namaycush) have been reestablished in most of Lake Superior, but have not been restored to 1929-1943 average abundance. Progress toward lake trout restoration in Lake Superior is described, management actions are reviewed, and the effectiveness of those actions is evaluated; especially stocking lake trout as a tool for building spawning stocks, and subsequently, populations of wild recruits. Widespread destruction of lake trout stocks in the 1950s due to an intense fishery and sea lamprey (Petromyzon marinus) predation resulted in lower overall phenotypic diversity than was previously present. Stocking of yearling lake trout, begun in the 1950s, produced high densities of spawners that reproduced wherever inshore spawning habitat was widespread. Sea lampreys were greatly reduced, beginning in 1961, using selective chemical toxicants and barrier dams, but continue to exert substantial mortality. Fishery regulation was least effective in Wisconsin, where excessive gillnet effort caused high by-catch of lake trout until 1991, and in eastern Michigan, where lake trout restoration was deferred in favor of a tribal fishery for lake whitefish (Coregonus clupeaformis) in 1985. Restoration of stocks was quicker in offshore areas where remnant wild lake trout survived and fishing intensity was low, and was slower in inshore areas where stocked lake trout reproduced successfully and fishing intensity was high. Inshore stocks of wild lake trout are currently about 61 % of historic abundance in Michigan and 53% in Wisconsin. Direct comparison of modern and historic abundances of inshore lake trout stocks in Minnesota and Ontario is impossible due to lack of historic stock assessment data. Stocks in Minnesota are less abundant at present than in Michigan or Wisconsin, and stocks in Ontario are similar to those in Michigan. Further progress in stock recovery can only be achieved if sea lampreys are depressed and if

  6. Sources and distribution of microplastics in China's largest inland lake - Qinghai Lake.

    PubMed

    Xiong, Xiong; Zhang, Kai; Chen, Xianchuan; Shi, Huahong; Luo, Ze; Wu, Chenxi

    2018-04-01

    Microplastic pollution was studied in China's largest inland lake - Qinghai Lake in this work. Microplastics were detected with abundance varies from 0.05 × 10 5 to 7.58 × 10 5 items km -2 in the lake surface water, 0.03 × 10 5 to 0.31 × 10 5 items km -2 in the inflowing rivers, 50 to 1292 items m -2 in the lakeshore sediment, and 2 to 15 items per individual in the fish samples, respectively. Small microplastics (0.1-0.5 mm) dominated in the lake surface water while large microplastics (1-5 mm) are more abundant in the river samples. Microplastics were predominantly in sheet and fiber shapes in the lake and river water samples but were more diverse in the lakeshore sediment samples. Polymer types of microplastics were mainly polyethylene (PE) and polypropylene (PP) as identified using Raman Spectroscopy. Spatially, microplastic abundance was the highest in the central part of the lake, likely due to the transport of lake current. Based on the higher abundance of microplastics near the tourist access points, plastic wastes from tourism are considered as an important source of microplastics in Qinghai Lake. As an important area for wildlife conservation, better waste management practice should be implemented, and waste disposal and recycling infrastructures should be improved for the protection of Qinghai Lake. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. 77 FR 23123 - Special Local Regulation; Smokin The Lake; Gulfport Lake; Gulfport, MS

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-18

    ...-AA08 Special Local Regulation; Smokin The Lake; Gulfport Lake; Gulfport, MS AGENCY: Coast Guard, DHS... regulation for a portion of Gulfport Lake in Gulfport, MS. This action is necessary for the safeguard of... The Lake high speed boat races on May 5 and 6, 2012. Entry into, transiting or anchoring in this area...

  8. A hidden curriculum: gambling and problem gambling among high school students in Auckland.

    PubMed

    Sullivan, Sean

    2005-12-01

    Participation in gambling by young people aged 13-18 years. During 2001, prior to the passing of legislation to minimise gambling harm, more than 500 students from six high schools completed a survey of their participation in gambling during the previous 12 months, and completed three problem gambling screens. Gambling, including under-age gambling, was a common event. Up to one in five were identified as at risk for problem gambling on at least one screen. Students who were non-European, or were from low socioeconomic areas, were more likely to be at risk for problem gambling. Help for gambling problems was preferred from friends and family rather than others, while inclusion of information in the education curriculum about risk of gambling problems was supported. The survey provided evidence for pre-legislation baseline gambling behaviour, and risk for problem gambling, of students attending high schools in Auckland. Levels of risk for problem gambling paralleled the elevated risk found for youth in many countries. Raising awareness, through a school curriculum, of risk for gambling problems among adolescents may be explored as a strategy to reduce the high levels of risk for gambling problems identified.

  9. Sediment deposition and selected water-quality characteristics in Cedar Lake and Lake Olathe, Northeast Kansas, 2000

    USGS Publications Warehouse

    Mau, D.P.

    2002-01-01

    The Lake Olathe watershed, located in northeast Kansas, was investigated using bathymetric survey data and reservoir bottom-sediment cores to determine sediment deposition, water-quality trends, and transport of nutrients (phosphorus and nitrogen species), selected trace elements, selected pesticides, and diatoms as indicators of eutrophic (organic-enriched and depleted oxygen supply) conditions. To determine sediment deposition and loads, bathymetric data from Cedar Lake and Lake Olathe, both located in the Lake Olathe watershed, were collected in 2000 and compared to historical topographic data collected when the lakes were built. Approximately 338 acre-feet of sediment deposition has occurred in Cedar Lake since dam closure in 1938, and 317 acre-feet has occurred at Lake Olathe since 1956. Mean annual sediment deposition was 5.45 acre-feet per year (0.89 acre-feet per year per square mile) for Cedar Lake and 7.0 acre-feet per year (0.42 acre-feet per year per square mile) for Lake Olathe. Mean annual sediment loads for the two reservoirs were 9.6 million pounds per year for Cedar Lake and 12.6 million pounds per year for Lake Olathe. Mean concentrations of total phosphorus in bottom-sediment samples from Cedar Lake ranged from 1,370 to 1,810 milligrams per kilogram, and concentrations in bottom-sediment samples from Lake Olathe ranged from 588 to 1,030 milligrams per kilogram. The implication of large total phosphorus concentrations in the bottom sediment of Cedar Lake is that inflow into Cedar Lake is rich in phosphorus and that adverse water-quality conditions could affect water quality in downstream Lake Olathe through discharge of water from Cedar Lake to Lake Olathe via Cedar Creek. Mean annual phosphorus loads transported from the Lake Olathe watershed were estimated to be 14,700 pounds per year for Cedar Lake and 9,720 pounds per year for Lake Olathe. The mean annual phosphorus yields were estimated to be 3.74 pounds per acre per year for Cedar Lake and 0

  10. Acoustic estimates of abundance and distribution of spawning lake trout on Sheboygan Reef in Lake Michigan

    USGS Publications Warehouse

    Warner, D.M.; Claramunt, R.M.; Janssen, J.; Jude, D.J.; Wattrus, N.

    2009-01-01

    Efforts to restore self-sustaining lake trout (Salvelinus namaycush) populations in the Laurentian Great Lakes have had widespread success in Lake Superior; but in other Great Lakes, populations of lake trout are maintained by stocking. Recruitment bottlenecks may be present at a number of stages of the reproduction process. To study eggs and fry, it is necessary to identify spawning locations, which is difficult in deep water. Acoustic sampling can be used to rapidly locate aggregations of fish (like spawning lake trout), describe their distribution, and estimate their abundance. To assess these capabilities for application to lake trout, we conducted an acoustic survey covering 22 km2 at Sheboygan Reef, a deep reef (<40 m summit) in southern Lake Michigan during fall 2005. Data collected with remotely operated vehicles (ROV) confirmed that fish were large lake trout, that lake trout were 1–2 m above bottom, and that spawning took place over specific habitat. Lake trout density exhibited a high degree of spatial structure (autocorrelation) up to a range of ~190 m, and highest lake trout and egg densities occurred over rough substrates (rubble and cobble) at the shallowest depths sampled (36–42 m). Mean lake trout density in the area surveyed (~2190 ha) was 5.8 fish/ha and the area surveyed contained an estimated 9500–16,000 large lake trout. Spatial aggregation in lake trout densities, similarity of depths and substrates at which high lake trout and egg densities occurred, and relatively low uncertainty in the lake trout density estimate indicate that acoustic sampling can be a useful complement to other sampling tools used in lake trout restoration research.

  11. Visualizing the geology of lake trout spawning sites, northern Lake Michigan

    USGS Publications Warehouse

    Dartnell, Peter; Barnes, Peter; Gardner, James V.; Lee, Kristen

    2004-01-01

    Geologists and biologists are working together to understand the links between lake floor geology (composition and shape) and the distribution of lake trout throughout their life cycle. Lake floor geology is one of the main factors determining where lake trout spawn, feed, and hide. In support of ongoing research to study Lake Michigan trout habitats, the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers mapped the morphology of principle lake trout spawning sites. Using the Army Corps of Engineer's SHOALS airborne lidar (Light Detection and Ranging) system we mapped six regions in Northern Lake Michigan in order to identify ideal spawning regions composed of shallow, clean, gravel/cobble substrate, adjacent to deeper water. Lidar mapping systems, which use laser pulses to measure water depths from an airplane, are now available to map the nearshore lake morphology at meter-scale detail. Maps generated from the bathymetric data are used to define regions with smooth homogeneous substrate, regions with higher relief, and mixed regions with both smooth and rough relief. This morphologic information combined with sediment samples and direct bottom observations enable geologists to map areas with rougher relief composed of rock outcrop, boulders, and cobbles, as well as smooth regions covered with sand or mud. This information helps biologists, fishery managers, and ecologists visualize the lake floor in significant detail which promotes better fishery management, species protection, and habitat identification. These maps present the maps and discuss the geology of the six lake trout spawning sites mapped by the lidar system. Where the mapping approached land, aerial photography of the land is combined with the bathymetric data to help visualize the scale of the offshore features. Map and perspective views of Boulder Reef, Hog Island Reef, and Little Traverse Bay are shown on sheet 1, whereas map and perspective views of Trout and High Island

  12. Visualizing the geology of lake trout spawning sites; northern Lake Michigan

    USGS Publications Warehouse

    Dartnell, Peter; Barnes, Peter; Gardner, James V.; Lee, Kristen

    2006-01-01

    Geologists and biologists are working together to understand the links between lake floor geology (composition and shape) and the distribution of lake trout throughout their life cycle. Lake floor geology is one of the main factors determining where lake trout spawn, feed, and hide. In support of ongoing research to study Lake Michigan trout habitats, the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers mapped the morphology of principle lake trout spawning sites. Using the Army Corps of Engineer's SHOALS airborne lidar (Light Detection and Ranging) system we mapped six regions in Northern Lake Michigan in order to identify ideal spawning regions composed of shallow, clean, gravel/cobble substrate, adjacent to deeper water. Lidar mapping systems, which use laser pulses to measure water depths from an airplane, are now available to map the nearshore lake morphology at meter-scale detail. Maps generated from the bathymetric data are used to define regions with smooth homogeneous substrate, regions with higher relief, and mixed regions with both smooth and rough relief. This morphologic information combined with sediment samples and direct bottom observations enable geologists to map areas with rougher relief composed of rock outcrop, boulders, and cobbles, as well as smooth regions covered with sand or mud. This information helps biologists, fishery managers, and ecologists visualize the lake floor in significant detail which promotes better fishery management, species protection, and habitat identification. These maps present the maps and discuss the geology of the six lake trout spawning sites mapped by the lidar system. Where the mapping approached land, aerial photography of the land is combined with the bathymetric data to help visualize the scale of the offshore features. Map and perspective views of Boulder Reef, Hog Island Reef, and Little Traverse Bay are shown on sheet 1, whereas map and perspective views of Trout and High Island

  13. A Killer Lake

    ERIC Educational Resources Information Center

    Horvath, Thomas

    2005-01-01

    In 1986, Lake Nyos, a volcanic lake in Cameroon, released a huge amount of carbon dioxide gas, killing over 1,700 people in the surrounding area. This case study, developed for use in a limnology or aquatic biology course, explores that event, introducing students to concepts relating to lake formation, thermal stratification, and dissolved gases.…

  14. LAKE-WETLAND LINKAGE AND PERIPHYTON DYNAMICS IN A LAKE SUPERIOR COASTAL WETLAND

    EPA Science Inventory

    Tributaries feeding coastal wetlands along the Wisconsin shore of Lake Superior are generally depleted in inorganic nitrogen (TIN) relative to phosphorus (SRP), while Lake Superior is phosphorous depleted and relatively rich in TIN. Within wetlands, mixing of tributary and lake w...

  15. The use of a co-design model in improving timely bleed reporting by adults with haemophilia living in the Auckland region of New Zealand.

    PubMed

    d'Young, A I; Young, L; Ockelford, P A; Brasser, M; Slavin, K; Manson, L; Preston, S

    2014-05-01

    Many adult patients diagnosed with phenotypically moderate and severe haemophilia living in the Auckland region of New Zealand do not report bleeding episodes within a timeframe that allows for optimal assessment and management. This can result in poor clinical outcomes for patients and poor oversight of the use of expensive clotting factor concentrates. Our goal was to improve both the number and speed at which bleeding episodes were reported to our centre, improving access to care and clinical oversight of the use of expensive factor concentrates and aiding the development of a care partnership with patients. We worked with 70 adult PWH living in the Auckland region of New Zealand with moderate and severe haemophilia A and B. Over a 5-month period between March and July 2013 we used a co-design model to develop and implement a range of strategies to improve the timing and frequency of bleed reporting. Mean bleed reporting time was reduced threefold, with a threefold increase in the number of bleeds reported per month. We reduced the number of bleeding episodes reported outside of a prespecified 48-h time limit by 68%. We significantly improved bleed reporting and time to report, indicating improved access to our services, improved clinical oversight and improved accountability to our national funder. We have achieved a care partnership and a reduction in factor consumption for the study population without compromising the quality of care they receive. © 2013 John Wiley & Sons Ltd.

  16. Great Salt Lake, Utah

    USGS Publications Warehouse

    Stephens, Doyle W.; Gardner, Joe F.

    1999-01-01

    This document is intended as a source of general information and facts about Great Salt Lake, Utah. This U.S. Geological Survey information sheet answers frequently asked questions about Great Salt Lake. Topics include: History, salinity, brine shrimp, brine flies, migratory birds, and recreation. Great Salt Lake, the shrunken remnant of prehistoric Lake Bonneville, has no outlet. Dissolved salts accumulate in the lake by evaporation. Salinity south of the causeway has ranged from 6 percent to 27 percent over a period of 22 years (2 to 7 times saltier than the ocean). The high salinity supports a mineral industry that extracts about 2 million tons of salt from the lake each year. The aquatic ecosystem consists of more than 30 species of organisms. Harvest of its best-known species, the brine shrimp, annually supplies millions of pounds of food for the aquaculture industry worldwide. The lake is used extensively by millions of migratory and nesting birds and is a place of solitude for people. All this occurs in a lake that is located at the bottom of a 35,000-square-mile drainage basin that has a human population of more than 1.5 million.

  17. Spring-summer diet of lake trout on Six Fathom Bank and Yankee Reef in Lake Huron

    USGS Publications Warehouse

    Madenjian, C.P.; Holuszko, J.D.; Desorcie, T.J.

    2006-01-01

    We examined the stomach contents of 1,045 lake trout (Salvelinus namaycush) caught on Six Fathom Bank and Yankee Reef, two offshore reef complexes in Lake Huron, during late spring and early summer 1998-2003. Lake trout ranged in total length from 213 to 858 mm, and in age from 2 to 14 years. In total, 742 stomachs contained food. On a wet-weight basis, alewife (Alosa pseudoharengus) dominated the spring-summer diet of lake trout on both of these offshore reef complexes. Alewives accounted for 75 to 90% of lake trout diet, depending on the lake trout size category. Size of alewives found in lake trout stomachs increased with increasing lake trout size. Faster growth of juvenile lake trout on Six Fathom Bank and Yankee Reef than on Sheboygan Reef in Lake Michigan was attributed to greater availability of small alewives on the offshore reefs in Lake Huron. Our findings indicated that alewives inhabited Six Fathom Bank and Yankee Reef during spring and summer months. Thus, our study provided support for the contention that alewives may have interfered with natural reproduction by lake trout on these offshore reef complexes in Lake Huron.

  18. Water quality of Fremont Lake and New Fork Lakes, western Wyoming; a progress report

    USGS Publications Warehouse

    Peterson, D.A.; Averett, R.C.; Mora, K.L.

    1987-01-01

    Fremont Lake and New Fork Lakes in the New Fork River drainage of western Wyoming were selected for a comprehensive study of hydrologic processes affecting mountain lakes in the Rocky Mountains. Information is needed about lakes in this area to assess their response to existing and planned development. The concerns include regional issues such as acid precipitation from gas-sweetening plants, coal-fired powerplants, and smelters, as well as local issues, such as shoreline development and raising outlet control structures. Onsite measurements indicated strong thermal stratification in the lakes during the summer. Isothermal conditions occurred during December 1983 and May 1984. Mean phytoplankton concentrations were less than 5,000 cells/ml, and chlorophyll a concentrations were weakly correlated with phytoplankton concentrations. Zooplankton concentrations were small, less than 6 organisms/L. The numbers of benthic invertebrates/unit area in Fremont Lake were extremely small. The lake waters and inflow and outflow streams were chemically dilute solutions. Mean dissolved-solids concentrations were 13 mg/L in Fremont Lake and 24 mg/L in New Fork Lakes. Calcium and bicarbonate were the predominant ions. Concentrations of phosphorus and nitrogen usually were less than detection limits. Trace-metals concentrations in the lakes were similar to those in precipitation and generally were small. Dissolved organic-carbon concentrations were about 1 mg/L. Concentrations of fulvic and humic acids were relatively large in the inlet of Fremont Lake during the spring. Pine Creek has deposited 800 metric tons of sediment, on an annual average, to the delta of Fremont Lake. Most sediment is deposited during spring runoff. (USGS)

  19. Attoriolong Tradition of Lake Preservation

    NASA Astrophysics Data System (ADS)

    Mustamin, Kamaruddin; Rahmawati, Rahmawati; Abbas, Abbas; Akbar, Akbar

    2018-05-01

    Lake as a source of life for the fishermen has a very significant potential in influencing the views and behaviour of the fishing community’s culture. Events such as tidal lake erratic, flooding, high hardness water waves, even the lack of fish catches and the death of sailors in the lake, are symptoms that serve as the base outlook for the fishermen errors that they do against the unseen force which they consider to be the ruler of the lake. The fishing community of Lake Tempe has run attoriolong and established rules related to the management of the lake since the pre-Islamic period (before 1610 AD), led by a Macua Tappareng. Macua Tappareng is considered understand the ancestor details and rules in controlling the use of the lake, including the mystical of the lake. This study explores the local wisdom of coastal fishing communities of Lake Tempe in interacting with the lake led by Macua Tappareng. Macua Tappareng hereditary ensures that attoriolong tradition with all the rules and policies related to the lake is applied correctly. This research is a descriptive-analytic study that intends to describe as well as analyze the regulations and procedures on how Macua Tappareng in preserving the lake. The research shows that Macua Tappareng has the legitimacy and strategic position in protecting the lake, as evidenced by the continued preservation of some rules of fishing, such as a ban on fishing in particular place and time. Besides, the tradition of Maccera’ Tappareng is still considered liabilities fishing communities in honour of the ruler of the lake even become additional tools of the governments in disseminating and implementing local regulations.

  20. Contaminant trends in lake trout and walleye from the Laurentian Great Lakes

    USGS Publications Warehouse

    DeVault, David S.; Hesselberg, Robert J.; Rodgers, Paul W.; Feist, Timothy J.

    1996-01-01

    Trends in PCBs, DDT, and other contaminants have been monitored in Great Lakes lake trout and walleye since the 1970s using composite samples of whole fish. Dramatic declines have been observed in concentrations of PCB, ΣDDT, dieldrin, and oxychlordane, with declines initially following first order loss kinetics. Mean PCB concentrations in Lake Michigan lake trout increased from 13 μg/g in 1972 to 23 μg/g in 1974, then declined to 2.6 μg/g by 1986. Between 1986 and 1992 there was little change in concentration, with 3.5 μg/g observed in 1992. ΣDDT in Lake Michigan trout followed a similar trend, decreasing from 19.2 μg/g in 1970 to 1.1 μg/g in 1986, and 1.2 μg/g in 1992. Similar trends were observed for PCBs and ΣDDT in lake trout from Lakes Superior, Huron and Ontario. Concentrations of both PCB and ΣDDT in Lake Erie walleye declined between 1977 and 1982, after which concentrations were relatively constant through 1990. When originally implemented it was assumed that trends in the mean contaminant concentrations in open-lake fish would serve as cost effective surrogates to trends in the water column. While water column data are still extremely limited it appears that for PCBs in lakes Michigan and Superior, trends in lake trout do reasonably mimic those in the water column over the long term. Hypotheses to explain the trends in contaminant concentrations are briefly reviewed. The original first order loss kinetics used to describe the initial decline do not explain the more recent leveling off of contaminant concentrations. Recent theories have examined the possibilities of multiple contaminant pools. We suggest another hypothesis, that changes in the food web may have resulted in increased bioaccumulation. However, a preliminary exploration of this hypothesis using a change point analysis was inconclusive.

  1. Stability of lava lakes

    NASA Astrophysics Data System (ADS)

    Witham, Fred; Llewellin, Edward W.

    2006-11-01

    A physical model of a generic lava lake system is developed. We derive the requisite conditions for the existence of an 'equilibrium lava lake' in which magmastatic pressure at the base of the conduit balances the pressure in the underlying magmatic reservoir. The stability of this lava lake system is tested by investigating the response of the system to perturbation. We develop a graphical method, based on the system's pressure-depth profile, to predict the subsequent behaviour of the system. Despite the simplicity of the modelled system, we find a broad behavioural spectrum. Initially, the rise of bubbles through the magma is ignored. In this case, both stable, long-lived lava lakes, and unstable lakes that are prone to sudden draining, are predicted. The stability of the system is shown to be controlled by lake-conduit geometry, the solubility and gas expansion laws and the magma's volatile content. We show that an unstable lake must collapse to a new, stable equilibrium. Subsequent recharge of the system by, for example, conduit overturn, would promote a return to the original equilibrium, giving rise to cyclic behaviour. Such a mechanism is consistent with lava lake behaviour during the 1983-1984 Pu'u 'O'o eruption of Kilauea. When the rise of bubbles through the magma is considered, our model predicts that stable lakes must drain over time. We, therefore, deduce that persistently degassing, stable lava lakes, such as those observed at Mt. Erebus, Antarctica, and Mauna Ulu, Kilauea, Hawaii, must have an effective conduit convection mechanism or an exogenous supply of bubbles from depth.

  2. Increasing thiamine concentrations in lake trout eggs from Lakes Huron and Michigan coincide with low alewife abundance

    USGS Publications Warehouse

    Riley, Stephen C.; Rinchard, Jacques; Honeyfield, Dale C.; Evans, Allison N.; Begnoche, Linda

    2011-01-01

    Lake trout Salvelinus namaycush in the Laurentian Great Lakes suffer from thiamine deficiency as a result of adult lake trout consuming prey containing thiaminase, a thiamine-degrading enzyme. Sufficiently low egg thiamine concentrations result in direct mortality of or sublethal effects on newly hatched lake trout fry. To determine the prevalence and severity of low thiamine in lake trout eggs, we monitored thiamine concentrations in lake trout eggs from 15 sites in Lakes Huron and Michigan from 2001 to 2009. Lake trout egg thiamine concentrations at most sites in both lakes were initially low and increased over time at 11 of 15 sites, and the proportion of females with egg thiamine concentrations lower than the recommended management objective of 4 nmol/g decreased over time at eight sites. Egg thiamine concentrations at five of six sites in Lakes Huron and Michigan were significantly inversely related to site-specific estimates of mean abundance of alewives Alosa pseudoharengus, and successful natural reproduction of lake trout has been observed in Lake Huron since the alewife population crashed. These results support the hypothesis that low egg thiamine in Great Lakes lake trout is associated with increased alewife abundance and that low alewife abundance may currently be a prerequisite for successful reproduction by lake trout in the Great Lakes.

  3. Glacial lakes in the Indian Himalayas--from an area-wide glacial lake inventory to on-site and modeling based risk assessment of critical glacial lakes.

    PubMed

    Worni, Raphael; Huggel, Christian; Stoffel, Markus

    2013-12-01

    Glacial lake hazards and glacial lake distributions are investigated in many glaciated regions of the world, but comparably little attention has been given to these topics in the Indian Himalayas. In this study we present a first area-wide glacial lake inventory, including a qualitative classification at 251 glacial lakes >0.01 km(2). Lakes were detected in the five states spanning the Indian Himalayas, and lake distribution pattern and lake characteristics were found to differ significantly between regions. Three glacial lakes, from different geographic and climatic regions within the Indian Himalayas were then selected for a detailed risk assessment. Lake outburst probability, potential outburst magnitudes and associated damage were evaluated on the basis of high-resolution satellite imagery, field assessments and through the use of a dynamic model. The glacial lakes analyzed in the states of Jammu and Kashmir and Himachal Pradesh were found to present moderate risks to downstream villages, whereas the lake in Sikkim severely threatens downstream locations. At the study site in Sikkim, a dam breach could trigger drainage of ca. 16×10(6)m(3) water and generate maximum lake discharge of nearly 7000 m(3) s(-). The identification of critical glacial lakes in the Indian Himalayas and the detailed risk assessments at three specific sites allow prioritizing further investigations and help in the definition of risk reduction actions. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. What can the National Lake Assessment Tell Us about Ecosystem Service Benefits in Lakes

    EPA Science Inventory

    The condition of lakes, ponds, and reservoirs is often viewed as existing along a continuum from pristine to impacted. The 2007 National Lake Survey was conducted to assess the condition of the nation’s lakes. Over 1,000 lakes were surveyed and detailed physical and chemical da...

  5. Lake Enriquillo, Dominican Republic

    NASA Image and Video Library

    2017-08-15

    Lake Enriquillo is a hypersaline lake in the Dominican Republic. In 2004, the lake covered an area of 164 square kilometers; by 2011, it had doubled in size and grown to 350 km2, inundating farmland and homes. Various reasons for the flooding include increases in rainfall; increase of sediments going into the lake, raising the lakebed; and milder temperatures, reducing surface evaporation. The lake is home to the largest population of American crocodiles in the Caribbean. The images were acquired October 26, 2003 and June 10, 2017, cover an area of 22.7 by 45.4 km, and are located at 18.5 degrees north, 71.6 degrees west. An image of Lake Enriquillo taken in 2003 is available at https://photojournal.jpl.nasa.gov/catalog/PIA21815

  6. Lake Erie...Take a Bow.

    ERIC Educational Resources Information Center

    Canning, Maureen; Dunlevy, Margie

    This elementary school teaching unit was developed as a part of a series of teaching units that deal with Lake Erie. This unit was developed to enable children to: (1) identify the Great Lakes and pick out Lake Erie on a map; (2) demonstrate knowledge of Lake Erie's origin and geography; (3) list some uses of Lake Erie; and (4) give examples of…

  7. Long-Term Variability of Satellite Lake Surface Water Temperatures in the Great Lakes

    NASA Astrophysics Data System (ADS)

    Gierach, M. M.; Matsumoto, K.; Holt, B.; McKinney, P. J.; Tokos, K.

    2014-12-01

    The Great Lakes are the largest group of freshwater lakes on Earth that approximately 37 million people depend upon for fresh drinking water, food, flood and drought mitigation, and natural resources that support industry, jobs, shipping and tourism. Recent reports have stated (e.g., the National Climate Assessment) that climate change can impact and exacerbate a range of risks to the Great Lakes, including changes in the range and distribution of certain fish species, increased invasive species and harmful algal blooms, declining beach health, and lengthened commercial navigation season. In this study, we will examine the impact of climate change on the Laurentian Great Lakes through investigation of long-term lake surface water temperatures (LSWT). We will use the ATSR Reprocessing for Climate: Lake Surface Water Temperature & Ice Cover (ARC-Lake) product over the period 1995-2012 to investigate individual and interlake variability. Specifically, we will quantify the seasonal amplitude of LSWTs, the first and last appearances of the 4°C isotherm (i.e., an important identifier of the seasonal evolution of the lakes denoting winter and summer stratification), and interpret these quantities in the context of global interannual climate variability such as ENSO.

  8. Side-scan sonar mapping of lake trout spawning habitat in northern Lake Michigan

    USGS Publications Warehouse

    Edsall, Thomas A.; Poe, Thomas P.; Nester, Robert T.; Brown, Charles L.

    1989-01-01

    Native stocks of lake trout Salvelinus namaycush were virtually or completely extirpated from the lower four Great Lakes by the early 1960s. The failure of early attempts to reestablish self-sustaining populations of lake trout was attributed partly to the practice of stocking hatcheryreared juveniles at locations and over substrates that had not been used in the past for spawning by native fish. Subsequent attempts to improve the selection of stocking locations were impeded by the lack of reliable information on the distribution of substrates on historical spawning grounds. Here we demonstrate the potential of side-scan sonar to substantially expand the data base needed to pinpoint the location of substrates where lake trout eggs, fry, or juveniles could be stocked to maximize survival and help ensure that survivors returning to spawn would encounter suitable substrates. We also describe the substrates and bathymetry of large areas on historical lake trout spawning grounds in the Fox Island Lake Trout Sanctuary in northern Lake Michigan. These areas could be used to support a contemporary self-sustaining lake trout population in the sanctuary and perhaps also in adjacent waters.

  9. Sexual difference in mercury concentrations of lake trout (Salvelinus namaycush) from Lake Ontario

    USGS Publications Warehouse

    Madenjian, C.P.; Keir, M.J.; Whittle, D.M.

    2011-01-01

    We determined total mercury (Hg) concentrations in 50 female lake trout (Salvelinus namaycush) and 69 male lake trout from Lake Ontario (Ontario, Canada and New York, United States). Results showed that, on average, males were 8% higher in Hg concentration than females in Lake Ontario. We also used bioenergetics modeling to determine whether a sexual difference in gross growth efficiency (GGE) could explain the observed sexual difference in Hg concentrations. According to the bioenergetics modeling results, male GGE was about 3% higher than female GGE, on average. Although the bioenergetics modeling could not explain the higher Hg concentrations exhibited by the males, a sexual difference in GGE remained a plausible explanation for the sexual difference in Hg concentrations of the lake trout. In an earlier study, male lake trout from Lake Ontario were found to be 22% higher in polychlorinated biphenyl (PCB) concentration than females from Lake Ontario. Thus, although males were higher in both Hg and PCB concentrations, the degree of the sexual difference in concentration varied between the two contaminants. Further research on sexual differences in Hg excretion rates and Hg direct uptake rates may be needed to resolve the disparity in results between the two contaminants.

  10. Recent lake ice-out phenology within and among lake districts of Alaska, U.S.A.

    USGS Publications Warehouse

    Arp, Christopher D.; Jones, Benjamin M.; Grosse, Guido

    2013-01-01

    The timing of ice-out in high latitudes is a fundamental threshold for lake ecosystems and an indicator of climate change. In lake-rich regions, the loss of ice cover also plays a key role in landscape and climatic processes. Thus, there is a need to understand lake ice phenology at multiple scales. In this study, we observed ice-out timing on 55 large lakes in 11 lake districts across Alaska from 2007 to 2012 using satellite imagery. Sensor networks in two lake districts validated satellite observations and provided comparison with smaller lakes. Over this 6 yr period, the mean lake ice-out for all lakes was 27 May and ranged from 07 May in Kenai to 06 July in Arctic Coastal Plain lake districts with relatively low inter-annual variability. Approximately 80% of the variation in ice-out timing was explained by the date of 0°C air temperature isotherm and lake area. Shoreline irregularity, watershed area, and river connectivity explained additional variation in some districts. Coherence in ice-out timing within the lakes of each district was consistently strong over this 6 yr period, ranging from r-values of 0.5 to 0.9. Inter-district analysis of coherence also showed synchronous ice-out patterns with the exception of the two arctic coastal districts where ice-out occurs later (June–July) and climatology is sea-ice influenced. These patterns of lake ice phenology provide a spatially extensive baseline describing short-term temporal variability, which will help decipher longer term trends in ice phenology and aid in representing the role of lake ice in land and climate models in northern landscapes.

  11. Mladotice Lake, Czechia: The unique genesis and evolution of the lake basin

    NASA Astrophysics Data System (ADS)

    Janský, Bohumír; Šobr, Miroslav; Kliment, Zdeněk; Chalupová, Dagmar

    2016-04-01

    The Mladotice Lake is a lake of unique genetic type in Czechia. In May 1872 a landslide as a result an extreme rainfall event occurred in western Czechia, blocking the Mladoticky stream valley and creating the Mladotice Lake. The 1952 and 1975 air images document that collective farming had a great impact on the lake basin evolution when balks and field terraces were removed and fields were made much larger. Because of this change in land use we expected higher soil erosion and a related increase in the sedimentation rate. First bathymetric measurements of the newly created lake were carried out in 1972 and were repeated in 1999, in 2003 and in 2014. Our analysis of the sedimentary record aims to identify the sediment stratigraphy, its basic physical and chemical properties, isotope content and thin sections yield a detailed temporal resolution of the sedimentation chronology. In some areas a sediment thickness of 4 m was detected. Hence, the average sedimentation rate is from 2.2 to 2.7 cm per year. KEY WORDS: Mladotice Lake - extreme rainfall event - landslide - land use changes - flood events - bathymetric measurements - sedimentation dynamics - stratigraphy and geochemistry of lake sediments - analyses of isotopes - sedimentation rates.

  12. Lake Garda, Italy

    NASA Image and Video Library

    2001-07-21

    This ASTER image was acquired on July 29, 2000 and covers an area of 30 by 57 km in northern Italy. Lake Garda was formed by glaciers during the last Ice Age, and is Italy's largest lake. Lago di Garda lies in the provinces of Verona, Brescia, and Trento, and is 51 kilometers (32 miles) long and from 3 to 18 kilometers (2 to 11 miles) wide. The Sarca is its chief affluent, and the lake is drained southward by the Mincio, which discharges into the Po River. Many villas are situated on its shores. On the peninsula of Sirmione, at the southern end of the lake, are the ruins of a Roman villa and a castle of the Scaligers, an Italian family of the 16th century. The RIGHT image has the land area masked out, and a harsh stretch was applied to the lake values to display variations in sediment load. Also visible are hundreds of boats and their wakes, criss-crossing the lake. The image is centered at 45.6 degrees north latitude, 10.6 degrees east longitude. http://photojournal.jpl.nasa.gov/catalog/PIA02671

  13. Airborne lidar detection and mapping of invasive lake trout in Yellowstone Lake.

    PubMed

    Roddewig, Michael R; Churnside, James H; Hauer, F Richard; Williams, Jacob; Bigelow, Patricia E; Koel, Todd M; Shaw, Joseph A

    2018-05-20

    The use of airborne lidar to survey fisheries has not yet been extensively applied in freshwater environments. In this study, we investigated the applicability of this technology to identify invasive lake trout (Salvelinus namaycush) in Yellowstone Lake, Yellowstone National Park, USA. Results of experimental trials conducted in 2004 and in 2015-16 provided lidar data that identified groups of fish coherent with current knowledge and models of lake trout spawning sites, and one identified site was later confirmed to have lake trout.

  14. Patterns in Benthic Biodiversity Link Lake Trophic Status to Structure and Potential Function of Three Large, Deep Lakes

    PubMed Central

    Hayford, Barbara L.; Caires, Andrea M.; Chandra, Sudeep; Girdner, Scott F.

    2015-01-01

    Relative to their scarcity, large, deep lakes support a large proportion of the world’s freshwater species. This biodiversity is threatened by human development and is in need of conservation. Direct comparison of biodiversity is the basis of biological monitoring for conservation but is difficult to conduct between large, insular ecosystems. The objective of our study was to conduct such a comparison of benthic biodiversity between three of the world’s largest lakes: Lake Tahoe, USA; Lake Hövsgöl, Mongolia; and Crater Lake, USA. We examined biodiversity of common benthic organism, the non-biting midges (Chironomidae) and determined lake trophic status using chironomid-based lake typology, tested whether community structure was similar between the three lakes despite geographic distance; and tested whether chironomid diversity would show significant variation within and between lakes. Typology analysis indicated that Lake Hövsgöl was ultra-oligotrophic, Crater Lake was oligotrophic, and Lake Tahoe was borderline oligotrophic/mesotrophic. These results were similar to traditional pelagic measures of lake trophic status for Lake Hövsgöl and Crater Lake but differed for Lake Tahoe, which has been designated as ultra-oligotrophic by traditional pelagic measures such as transparency found in the literature. Analysis of similarity showed that Lake Tahoe and Lake Hövsgöl chironomid communities were more similar to each other than either was to Crater Lake communities. Diversity varied between the three lakes and spatially within each lake. This research shows that chironomid communities from these large lakes were sensitive to trophic conditions. Chironomid communities were similar between the deep environments of Lake Hövsgöl and Lake Tahoe, indicating that chironomid communities from these lakes may be useful in comparing trophic state changes in large lakes. Spatial variation in Lake Tahoe’s diversity is indicative of differential response of chironomid

  15. Status of lake trout rehabilitation on Six Fathom Bank and Yankee Reef in Lake Huron

    USGS Publications Warehouse

    Madenjian, Charles P.; DeSorcie, Timothy J.; McClain, Jerry R.; Woldt, Aaron P.; Holuszko, Jeffrey D.; Bowen, Charles A.

    2004-01-01

    Six Fathom Bank, an offshore reef in the central region of Lake Huron's main basin, was stocked annually with hatchery-reared lake trout Salvelinus namaycush during 1985–1998, and nearby Yankee Reef was stocked with hatchery-reared lake trout in 1992, 1997, and annually during 1999–2001. We conducted gill-net surveys during spring and fall to evaluate performances of each of the various strains of lake trout, as well as the performance of the entire lake trout population (all strains pooled), on these two offshore reefs during 1992–2000. Criteria to evaluate performance included the proportion of “wild” fish within the population, spawner density, adult survival, growth, maturity, and wounding rate by sea lamprey Petromyzon marinus. Although naturally reproduced age-0 lake trout fry were caught on Six Fathom Bank and Yankee Reef, wild lake trout did not recruit to the adult population to any detectable degree. The density of spawning lake trout on Six Fathom Bank (>100 fish/305 m of gill net) during 1995–1998 appeared to be sufficiently high to initiate a self-sustaining population. However, annual mortality estimates for all lake trout strains pooled from catch curve analyses ranged from 0.48 to 0.62, well exceeding the target level of 0.40 suggested for lake trout rehabilitation. Annual mortality rate for the Seneca Lake strain (0.34) was significantly lower than that for the Superior–Marquette (0.69) and Lewis Lake (0.69) strains. This disparity in survival among strains was probably attributable to the lower sea-lamprey-induced mortality experienced by the Seneca Lake strain. The relatively high mortality experienced by adult lake trout partly contributed to the lack of successful natural recruitment to the adult population on these offshore reefs, but other factors were probably also involved. We recommend that both stocking of the Seneca Lake strain and enhanced efforts to reduce sea lamprey abundance in Lake Huron be continued.

  16. Temperate Lakes Discovered on Titan

    NASA Astrophysics Data System (ADS)

    Vixie, Graham; Barnes, Jason W.; Jackson, Brian; Wilson, Paul

    2012-04-01

    We have discovered two temperate lakes on Titan using Cassini's Visual and Infrared Mapping Spectrometer (VIMS). Three key features help to identify these surface features as lakes: morphology, albedo, and specular reflection. The presence of lakes at the mid-latitudes mean liquid can accumulate and remain stable outside of the poles. We first identify a lake surface by looking for possible shorelines with a lacustrine morphology. Then, we apply a simple atmospheric correction that produces an approximate surface albedo. Next, we prepare cylindrical projection maps of the brightness of the sky as seen from any points on the surface to identify specular reflections. Our techniques can then be applied to other areas, such as Arrakis Planitia, to test for liquid. Currently, all the known lakes on Titan are concentrated at the poles. Lakes have been suggested in the tropic zone by Griffith et al. Our discovery of non-transient, temperate lakes has important implications for Titan's hydrologic cycle. Clouds have been recorded accumulating in the mid-latitudes and areas have been darkened by rainfall but later brightened after evaporation (Turtle et al. 2011). Stable temperate lakes would affect total rainfall, liquid accumulation, evaporation rates, and infiltration. Polaznik Macula (Figure 1) is a great candidate for lake filling, evaporation rates, and stability. References: Griffith, C., et al.: "Evidence for Lakes on Titan's Tropical Surface". AAS/Division for Planetary Sciences Meeting Abstracts #42, Vol. 42, pp. 1077, 2010. Turtle, E. P., et al.: "Rapid and Extensive Surface Changes Near Titan's Equator: Evidence of April Showers". Science, Vol. 331, pp. 1414-, 2011. Figure 1: Polaznik Macula is the large, dark area central to the figure. The encircled dark blue areas represent positively identified lake regions in the T66 flyby. The light blue areas represent lake candidates still under analysis. The green circle marks a non-lake surface feature enclosed by a

  17. 14 CFR 93.69 - Special requirements, Lake Campbell and Sixmile Lake Airports.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES... person operating an aircraft to or from Lake Campbell or Sixmile Lake Airport shall conform to the flow of traffic for the Lake operations that are depicted on the appropriate aeronautical charts. ...

  18. 14 CFR 93.69 - Special requirements, Lake Campbell and Sixmile Lake Airports.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES... person operating an aircraft to or from Lake Campbell or Sixmile Lake Airport shall conform to the flow of traffic for the Lake operations that are depicted on the appropriate aeronautical charts. ...

  19. 14 CFR 93.69 - Special requirements, Lake Campbell and Sixmile Lake Airports.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES... person operating an aircraft to or from Lake Campbell or Sixmile Lake Airport shall conform to the flow of traffic for the Lake operations that are depicted on the appropriate aeronautical charts. ...

  20. 14 CFR 93.69 - Special requirements, Lake Campbell and Sixmile Lake Airports.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES... person operating an aircraft to or from Lake Campbell or Sixmile Lake Airport shall conform to the flow of traffic for the Lake operations that are depicted on the appropriate aeronautical charts. ...

  1. 14 CFR 93.69 - Special requirements, Lake Campbell and Sixmile Lake Airports.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES... person operating an aircraft to or from Lake Campbell or Sixmile Lake Airport shall conform to the flow of traffic for the Lake operations that are depicted on the appropriate aeronautical charts. ...

  2. The Volume of Earth's Lakes

    NASA Astrophysics Data System (ADS)

    Cael, B. B.

    How much water do lakes on Earth hold? Global lake volume estimates are scarce, highly variable, and poorly documented. We develop a mechanistic null model for estimating global lake mean depth and volume based on a statistical topographic approach to Earth's surface. The volume-area scaling prediction is accurate and consistent within and across lake datasets spanning diverse regions. We applied these relationships to a global lake area census to estimate global lake volume and depth. The volume of Earth's lakes is 199,000 km3 (95% confidence interval 196,000-202,000 km3) . This volume is in the range of historical estimates (166,000-280,000 km3) , but the overall mean depth of 41.8 m (95% CI 41.2-42.4 m) is significantly lower than previous estimates (62 - 151 m). These results highlight and constrain the relative scarcity of lake waters in the hydrosphere and have implications for the role of lakes in global biogeochemical cycles. We also evaluate the size (area) distribution of lakes on Earth compared to expectations from percolation theory. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. 2388357.

  3. Response of slimy sculpins to predation by juvenile lake trout in southern Lake Ontario

    USGS Publications Warehouse

    Owens, Randall W.; Bergstedt, Roger A.

    1994-01-01

    Abundance and biomass of slimy sculpin Cottus cognatus declined in Lake Ontario at depths most frequently occupied by juvenile lake trout Salvelinus namaycush (<70 m), but not at greater depths, during 1980–1987. The abundance of juvenile lake trout increased at depths less than 70 m between 1980 and 1987, and slimy sculpin abundance was negatively correlated with lake trout abundance. The size of slimy sculpins caught at depths less than 70 m decreased between 1980 and 1987, fish 50–99 mm becoming less common and fish 100 mm or longer becoming rare. The size of slimy sculpins at depths greater than 70 m did not change, Because slimy sculpins are the principal fish eaten by juvenile lake trout, and because juvenile lake trout were most abundant at depths where the greatest changes in the slimy sculpin population took place, we conclude that juvenile lake trout in Lake Ontario altered the slimy sculpin population. No significant negative correlations were found between abundance of slimy sculpins and those of the two most abundant fishes in Lake Ontario: Alewife Alosa pseudoharengus and rainbow smeltOsmerus mordax.

  4. Real-estate lakes

    USGS Publications Warehouse

    Rickert, David A.; Spieker, Andrew Maute

    1971-01-01

    Since the dawn of civilization waterfront land has been an irresistible attraction to man. Throughout history he has sought out locations fronting on oceans, rivers, and lakes. Originally sought for proximity .to water supply and transportation, such locations are now sought more for their esthetic qualities and for recreation. Usable natural waterfront property is limited, however, and the more desirable sites in many of our urban areas have already been taken. The lack of available waterfront sites has led to the creation of many artificial bodies of water. The rapid suburbanization that has characterized urban growth in America since the end of World War II, together with increasing affluence and le-isure time, has created a ready market for waterfront property. Accordingly, lake-centered subdivisions and developments dot the suburban landscape in many of our major urban areas. Literally thousands of lakes surrounded by homes have materialized during this period of rapid growth. Recently, several "new town" communities have been planned around this lake-centered concept. A lake can be either an asset or a liaoility to a community. A clean, clear, attractively landscaped lake is a definite asset, whereas a weed-choked, foul-smelling mudhole is a distinct liability. The urban environment poses both problems and imaginative opportunities in the development of lakes. Creation of a lake causes changes in all aspects of the environment. Hydrologic systems and ecological patterns are usually most severely altered. The developer should be aware of the potential changes; it is not sufficient merely to build a dam across a stream or to dig a hole in the ground. Development of Gl a successful lake requires careful planning for site selection and design, followed by thorough and cc ntinual management. The purpose of this report is to describe the characteristics of real-estate lakes, to pinpoint potential pmblems, and to suggest possible planning and management guidelines

  5. Circulation and sedimentation in a tidal-influenced fjord lake: Lake McKerrow, New Zealand

    NASA Astrophysics Data System (ADS)

    Pickrill, R. A.; Irwin, J.; Shakespeare, B. S.

    1981-01-01

    Lake McKerrow is a tide-influenced fjord lake, separated from the open sea by a Holocene barrier spit. Fresh, oxygenated waters of the epilimnion overlie saline, deoxygenated waters of the hypolimnion. During winter, water from the Upper Hollyford River interflows along the pycnocline, depositing coarse silt on the steep delta and transporting finer sediment down-lake. An extensive sub-lacustrine channel system on the foreset delta slope is possibly maintained by turbidity currents. Saline waters of the hypolimnion are periodically replenished. During high tides and low lake levels saline water flows into the lake and downslope into the lake basin as a density current in a well defined channel.

  6. Lake Eyre

    Atmospheric Science Data Center

    2013-04-16

    ... lake, and becomes dense with birds, frogs and colorful plant life. The Lake responds to extended dry periods (often associated with El Niño ... NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Science Mission Directorate, Washington, D.C. The Terra spacecraft is managed ...

  7. Hydrogeologic controls on the groundwater interactions with an acidic lake in karst terrain, Lake Barco, Florida

    USGS Publications Warehouse

    Lee, T.M.

    1996-01-01

    Transient groundwater interactions and lake stage were simulated for Lake Barco, an acidic seepage lake in the mantled karst of north central Florida. Karst subsidence features affected groundwater flow patterns in the basin and groundwater fluxes to and from the lake. Subsidence features peripheral to the lake intercepted potential groundwater inflow and increased leakage from the shallow perimeter of the lake bed. Simulated groundwater fluxes were checked against net groundwater flow derived from a detailed lake hydrologic budget with short-term lake evaporation computed by the energy budget method. Discrepancies between modeled and budget-derived net groundwater flows indicated that the model underestimated groundwater inflow, possibly contributed to by transient water table mounding near the lake. Recharge from rainfall reduced lake leakage by 10 to 15 times more than it increased groundwater inflow. As a result of the karst setting, the contributing groundwater basin to the lake was 2.4 ha for simulated average rainfall conditions, compared to the topographically derived drainage basin area of 81 ha. Short groundwater inflow path lines and rapid travel times limit the contribution of acid-neutralizing solutes from the basin, making Lake Barco susceptible to increased acidification by acid rain.

  8. Genetic variability among lake whitefish from Isle Royale and the Upper Great Lakes

    USGS Publications Warehouse

    Stott, Wendylee; Todd, Thomas N.; Kallemeyn, Larry

    2004-01-01

    The coregonine fishes from Isle Royale National Park represent a unique group that has escaped the successional changes observed elsewhere in North America. Analysis of microsatellite DNA loci revealed significant genetic differences among samples of lake whitefish (Coregonus clupeaformis) from Isle Royale, Lake Superior, and Lake Huron. The amount of genetic variation observed is consistent with that seen in other studies of whitefishes from North America. The lake whitefish from Isle Royale had previously been assigned sub-species status, but no evidence was found to support this. The effects of common ancestry and demographics both play a role in determining the relatedness of the populations. As with other fish species from Isle Royale and the upper Great Lakes, the lake whitefish have their origins in the Mississippi refugium.

  9. A combined field and numerical approach to understanding dilute pyroclastic density current dynamics and hazard potential: Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Brand, Brittany D.; Gravley, Darren M.; Clarke, Amanda B.; Lindsay, Jan M.; Bloomberg, Simon H.; Agustin-Flores, Javier; Németh, Károly

    2014-04-01

    The most dangerous and deadly hazards associated with phreatomagmatic eruptions in the Auckland Volcanic Field (AVF; Auckland, New Zealand) are those related to volcanic base surges - dilute, ground-hugging, particle laden currents with dynamic pressures capable of severe to complete structural damage. We use the well-exposed base surge deposits of the Maungataketake tuff ring (Manukau coast, Auckland), to reconstruct flow dynamics and destructive potential of base surges produced during the eruption. The initial base surge(s) snapped trees up to 0.5 m in diameter near their base as far as 0.7-0.9 km from the vent. Beyond this distance the trees were encapsulated and buried by the surge in growth position. Using the tree diameter and yield strength of the wood we calculate that dynamic pressures (Pdyn) in excess of 12-35 kPa are necessary to cause the observed damage. Next we develop a quantitative model for flow of and sedimentation from a radially-spreading, dilute pyroclastic density currents (PDCs) to determine the damage potential of the base surges produced during the early phases of the eruption and explore the implications of this potential on future eruptions in the region. We find that initial conditions with velocities on the order of 65 m s- 1, bulk density of 38 kg m- 3 and initial, near-vent current thicknesses of 60 m reproduce the field-based Pdyn estimates and runout distances. A sensitivity analysis revealed that lower initial bulk densities result in shorter run-out distances, more rapid deceleration of the current and lower dynamic pressures. Initial velocity does not have a strong influence on run-out distance, although higher initial velocity and slope slightly decrease runout distance due to higher rates of atmospheric entrainment. Using this model we determine that for base surges with runout distances of up to 4 km, complete destruction can be expected within 0.5 km from the vent, moderate destruction can be expected up to 2 km, but much

  10. Water quality of selected lakes in Mount Rainier National Park, Washington with respect to lake acidification

    USGS Publications Warehouse

    Turney, G.L.; Dion, N.P.; Sumioka, S.S.

    1986-01-01

    Thirteen lakes in Mount Rainier National Park were evaluated for general chemical characteristics, sensitivity to acidification by acidic precipitation, and degree of existing acidification. The lakes studies were Allen, one of the Chenuis group, Crescent , Crystal, Eleanor, Fan, one of the Golden group, Marsh, Mowich, Mystic, Shriner, and two unnamed lakes. The lakes were sampled in August 1983. Specific conductance values were generally 21 microsiemens/cm at 25 C or less, and dissolved solids concentrations were generally 20 mg/L or less. The major cations were calcium and sodium, and the major anion was bicarbonate. Alkalinity concentrations ranged from 2.1 to 9.0 mg/L in 12 of the lakes. Allen Lake was the exception, having an alkalinity concentration of 27 mg/L. The pH values for all of the lakes ranged from 5.8 to 6.5. In most of the lakes, vertical profiles of temperature, dissolved oxygen, pH, and specific conductance were relatively uniform. In the deeper lakes, temperature decreased with depth and dissolved-oxygen concentrations increased to about 20 feet, remained constant to 80 ft, then decreased with increasing depth. Exceptions to general water quality patterns were observed in three lakes. Allen Lake had a specific conductance value of 58 Microsiemens/cm. The lake of the Golden group was anaerobic at the bottom and had relatively high concentrations of dissolved organic carbon and dissolved metals, and a lower light transmission than the other lakes studied. One of the unnamed lakes had relatively high concentrations of phytoplankton and dissolved organic carbon and relatively low levels of light transmission. Comparisons of lake data to acid-sensitivity thresholds for specific conductance and alkalinity indicated that all of the lakes except Allen would be sensitive to acidic precipitation. The small sizes of the lakes, and their locations in basins of high precipitation and weathering-resistant rock types, enhance their sensitivity. None of the

  11. Discrimination among spawning concentrations of Lake Superior lake herring based on trace element profiles in sagittae

    USGS Publications Warehouse

    Bronte, Charles R.; Hesselberg, Robert J.; Shoesmith, John A.; Hoff, Michael H.

    1996-01-01

    Little is known about the stock structure of lake herring Coregonus artedi in Lake Superior, and recent increases in harvestable stock sizes has led to expanded exploitation in some areas. Research on marine teleosts has demonstrated that chemical differences in sagittal otoliths can be used for identification of fish stocks. We used plasma emission spectrophotometry to measure the concentrations of 10 trace elements in the sagittal otoliths from lake herring captured at eight spawning sites in Lake Superior and from Little Star Lake, an inland lake outside the Lake Superior basin. Discriminant function analysis indicated that elemental concentrations provided site-specific information but that considerable overlap existed among some locations, especially those in western Lake Superior. Correct classification rates varied from 12.0% to 86.1% and were generally higher for spawning locations from embayments in eastern Lake Superior and for the outgroup population from Little Star Lake. The results presented here demonstrate the potential usefulness of this technique for strictly freshwater species, especially those that live in highly oligotrophic waters such as Lake Superior.

  12. Limnology of Botos Lake, a tropical crater lake in Costa Rica.

    PubMed

    Umaña, G

    2001-12-01

    Botos Lake, located at the Poas Volcano complex (Costa Rica) was sampled eight times from 1994 to 1996 for physicochemical conditions of the water column and phytoplanktonic community composition. Depth was measured at fixed intervals in several transects across the lake to determine its main morphometric characteristics. The lake has an outlet to the north. It is located 2580 m above sea level and is shallow, with a mean depth of 1.8 m and a relative depth of 2.42 (surface area 10.33 ha, estimated volume 47.3 hm3). The lake showed an isothermal water column in all occasions, but it heats and cools completely according to weather fluctuations. Water transparency reached the bottom on most occasions (> 9 m). The results support the idea that the lake is polymictic and oligotrophic. The lake has at least 23 species of planktonic algae, but it was always dominated by dinoflagellates, especially Peridinium inconspicuum. The shore line is populated by a sparse population of Isoetes sp. and Eleocharis sp. mainly in the northern shore where the bottom has a gentle slope and the forest does not reach the shore.

  13. Antibiotics and Antibiotic Resistance Genes in Sediment of Honghu Lake and East Dongting Lake, China.

    PubMed

    Yang, Yuyi; Cao, Xinhua; Lin, Hui; Wang, Jun

    2016-11-01

    Sediment is an ideal medium for the aggregation and dissemination of antibiotics and antibiotic resistance genes (ARGs). The levels of antibiotics and ARGs in Honghu Lake and East Dongting Lake of central China were investigated in this study. The concentrations of eight antibiotics (four sulfonamides and four tetracyclines) in Honghu Lake were in the range 90.00-437.43 μg kg -1 (dry weight (dw)) with mean value of 278.21 μg kg -1 dw, which was significantly higher than those in East Dongting Lake (60.02-321.04 μg kg -1 dw, mean value of 195.70 μg kg -1 dw). Among the tested three sulfonamide resistance genes (sul) and eight tetracycline resistance genes (tet), sul1, sul2, tetA, tetC, and tetM had 100 % detection frequency in sediment samples of East Dongting Lake, while only sul1, sul2, and tetC were observed in all samples of Honghu Lake. The relative abundance of sul2 was higher than that of sul1 at p < 0.05 level in both lakes. The relative abundance of tet genes in East Dongting Lake was in the following order: tetM > tetB > tetC > tetA. The relative abundance of sul1, sul2, and tetC in East Dongting Lake was significantly higher than those in Honghu Lake. The abundance of background bacteria may play an important role in the horizontal spread of sul2 and tetC genes in Honghu Lake and sul1 in East Dongting Lake, respectively. Redundancy analysis indicated that tetracyclines may play a more important role than sulfonamides in the abundance of sul1, sul2, and tetC gens in Honghu Lake and East Dongting Lake.

  14. Functional convergence among pelagic sculpins of Lake Baikal and deepwater ciscoes of the Great Lakes

    USGS Publications Warehouse

    Eshenroder, Randy L.; Sideleva, Valentina G.; Todd, Thomas N.

    1999-01-01

    The vast, well-oxygenated hypolimnia of Lake Baikal and the Great Lakes were both dominated by endemic planktivorous fishes. These dominants, two species of sculpins (Comephorus, Comephoridae) in Lake Baikal and six species of deepwater ciscoes (Coregonus, Salmonidae) in the Great Lakes, although distant taxonomically, have morphologies suggesting a surprising degree of functional convergence. Here it is proposed that the same two buoyancy-regulation strategies observed in Baikal sculpins also arose in the deepwater ciscoes of the Great Lakes. One strategy favors hydrostatic lift (generated by low specific gravity) and is characterized by fatter, larger-bodied fish with smaller paired fins; the second strategy favors hydrodynamic lift (generated by swimming) and is characterized by leaner, smaller-bodied fish with larger paired fins. Both types likely evolved to feed on a single species of ecologically analogous, vertically migrating macrozooplankter: Macrohectopus branickii in Lake Baikal and Mysis relicta in the Great Lakes. It is suggested that Coregonus did not diversify and proliferate in Lake Baikal as they did in the Great Lakes because by the time Coregonus colonized Lake Baikal, pelagic sculpins were already dominant.

  15. Making the invisible visible: a Photovoice exploration of homeless women's health and lives in central Auckland.

    PubMed

    Bukowski, Kate; Buetow, Stephen

    2011-03-01

    Women and the concept of homelessness are weakly connected in the international discourses on health and housing. This PhotoVoice study gave a sample of homeless women in central Auckland a camera with which to photograph their lives in order to voice their felt health needs as advocates and agents for positive change. Interviews explored the meanings given to street lives captured in the photographs and reveal threats to the women's mental health and worsening addictions. Their tight-knit, resilient community, including dogs, was seen as 'family' who provide support and protection. The women perceived social services as helping them survive and support their health, but not ending their homelessness. Barriers to them getting and staying off the street included a shortage of affordable, secure housing, which has also tended to become overcrowded. They identified their own leaders who could link with state housing services to implement and evaluate new homelessness programmes, such as Housing First. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Microbial community structure in the gut of the New Zealand insect Auckland tree weta (Hemideina thoracica).

    PubMed

    Waite, David W; Dsouza, Melissa; Biswas, Kristi; Ward, Darren F; Deines, Peter; Taylor, Michael W

    2015-05-01

    The endemic New Zealand weta is an enigmatic insect. Although the insect is well known by its distinctive name, considerable size, and morphology, many basic aspects of weta biology remain unknown. Here, we employed cultivation-independent enumeration techniques and rRNA gene sequencing to investigate the gut microbiota of the Auckland tree weta (Hemideina thoracica). Fluorescence in situ hybridisation performed on different sections of the gut revealed a bacterial community of fluctuating density, while rRNA gene-targeted amplicon pyrosequencing revealed the presence of a microbial community containing high bacterial diversity, but an apparent absence of archaea. Bacteria were further studied using full-length 16S rRNA gene sequences, with statistical testing of bacterial community membership against publicly available termite- and cockroach-derived sequences, revealing that the weta gut microbiota is similar to that of cockroaches. These data represent the first analysis of the weta microbiota and provide initial insights into the potential function of these microorganisms.

  17. Lake Constance

    Atmospheric Science Data Center

    2013-04-17

    ... the left-hand side of the image is bordered by Switzerland, Germany, and Austria, and has several names. Lake Constance (also written as ... is about 70 kilometers from the lakeside town of Konstanz, Germany. An annual Celtic music festival is hosted on the Swiss shores of Lake ...

  18. LAKE FORK

    EPA Science Inventory

    The Lake Fork of the Arkansas River Watershed has been adversely affected through mining, water diversion and storage projects, grazing, logging, and other human influences over the past 120 years. It is the goals of the LFWWG to improve the health of Lake fork by addressing th...

  19. Usefulness of natural regions for lake management: Analysis of variation among lakes in northwestern Wisconsin, USA

    NASA Astrophysics Data System (ADS)

    Omernik, James M.; Rohm, Christina M.; Lillie, Richard A.; Mesner, Nancy

    1991-03-01

    A map of summer total phosphorus in lakes was compiled recently for a three-state area of the upper Midwest for purposes of identifying regional patterns of total phosphorus in lakes and attainable lake trophic state. Spatial patterns in total phosphorus from approximately 3000 lakes were studied in conjunction with maps of geographic characteristics that tend to affect phosphorus balance in lakes to identify regions of similarity in phosphorus concentrations in lakes or similarity in the mosaic of values as compared to adjacent areas. While degrees of relative homogeneity are apparent at many scales, the map was designed at a scale that would yield regions with sufficient homogeneity to be useful for lake management throughout the area. In this study, data from 210 lakes in a 1560-mi2 area in northwestern Wisconsin, sampled by the Wisconsin Department of Natural Resources in the spring of 1988 (subsequent to the compilation of the phosphorus map), were examined to: (1) substantiate the existence of the regions depicted on the map in northwest Wisconsin, (2) determine the nature and relative precision of the regional boundaries, (3) determine the relative importance of natural and anthropogenic watershed characteristics, lake types, lake area, and lake depth in explaining within-region differences in lake phosphorus, and (4) demonstrate how the regions might be used by local lake managers.

  20. Genetic assessment of strain-specific sources of lake trout recruitment in the Great Lakes

    USGS Publications Warehouse

    Page, Kevin S.; Scribner, Kim T.; Bennett, Kristine R.; Garzel, Laura M.; Burnham-Curtis, Mary K.

    2003-01-01

    Populations of wild lake trout Salvelinus namaycush have been extirpated from nearly all their historical habitats across the Great Lakes. Efforts to restore self-sustaining lake trout populations in U.S. waters have emphasized the stocking of coded-wire-tagged juveniles from six hatchery strains (Seneca Lake, Lewis Lake, Green Lake, Apostle Islands, Isle Royale, and Marquette) into vacant habitats. Strain-specific stocking success has historically been based on estimates of the survival and catch rates of coded-wire-tagged adults returning to spawning sites. However, traditional marking methods and estimates of relative strain abundance provide no means of assessing strain fitness (i.e., the realized contributions to natural recruitment) except by assuming that young-of-the-year production is proportional to adult spawner abundance. We used microsatellite genetic data collected from six hatchery strains with likelihood-based individual assignment tests (IA) and mixed-stock analysis (MSA) to identify the strain composition of young of the year recruited each year. We show that strain classifications based on IA and MSA were concordant and that the accuracy of both methods varied based on strain composition. Analyses of young-of-the-year lake trout samples from Little Traverse Bay (Lake Michigan) and Six Fathom Bank (Lake Huron) revealed that strain contributions differed significantly from estimates of the strain composition of adults returning to spawning reefs. The Seneca Lake strain contributed the majority of juveniles produced on Six Fathom Bank and more young of the year than expected within Little Traverse Bay. Microsatellite markers provided a method for accurately classifying the lake trout hatchery strains used for restoration efforts in the Great Lakes and for assessment of strain-specific reproductive success.

  1. Use of egg traps to investigate lake trout spawning in the Great Lakes

    USGS Publications Warehouse

    Schreiner, Donald R.; Bronte, Charles R.; Payne, N. Robert; Fitzsimons, John D.; Casselman, John M.

    1995-01-01

    Disk-shaped traps were used to examine egg deposition by lake trout (Salvelinus namaycush) at 29 sites in the Great Lakes. The main objectives were to; first, evaluate the disk trap as a device for sampling lake trout eggs in the Great Lakes, and second, summarize what has been learned about lake trout spawning through the use of disk traps. Of the 5,085 traps set, 60% were classified as functional when retrieved. Evidence of lake trout egg deposition was documented in each of the lakes studied at 14 of 29 sites. A total of 1,147 eggs were trapped. The percentage of traps functioning and catch per effort were compared among sites based on depth, timing of egg deposition, distance from shore, size of reef, and type of reef (artificial or natural). Most eggs were caught on small, shallow, protected reefs that were close to shore. Use of disk traps on large, shallow, unprotected offshore reefs or along unprotected shorelines was generally unsuccessful due to the effects of heavy wind and wave action. Making multiple lifts at short intervals, and retrieval before and re-deployment after storms are recommended for use in exposed areas. On large reefs, preliminary surveys to identify preferred lake trout spawning habitat may be required to deploy disk traps most effectively. Egg deposition by hatchery-reared fish was widespread throughout the Great Lakes, and the use of artificial structures by these fish was extensive.

  2. 75 FR 34934 - Safety Zone; Fireworks for the Virginia Lake Festival, Buggs Island Lake, Clarksville, VA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-21

    ...-AA00 Safety Zone; Fireworks for the Virginia Lake Festival, Buggs Island Lake, Clarksville, VA AGENCY... Fireworks for the Virginia Lake Festival event. This action is intended to restrict vessel traffic movement... Virginia Lake Festival, Buggs Island Lake, Clarksville, VA (a) Regulated Area. The following area is a...

  3. 78 FR 53677 - Safety Zone; Battle of Lake Erie Fireworks, Lake Erie, Put-In-Bay, OH

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-30

    ...-AA00 Safety Zone; Battle of Lake Erie Fireworks, Lake Erie, Put-In- Bay, OH AGENCY: Coast Guard, DHS... waters of Lake Erie, Put-In-Bay, Ohio. This zone is intended to restrict vessels from a portion of Lake Erie during the Battle of Lake Erie Fireworks. [[Page 53678

  4. Increasing incidence and age at diagnosis among children with type 1 diabetes mellitus over a 20-year period in Auckland (New Zealand).

    PubMed

    Derraik, José G B; Reed, Peter W; Jefferies, Craig; Cutfield, Samuel W; Hofman, Paul L; Cutfield, Wayne S

    2012-01-01

    We aimed to evaluate the incidence of type 1 diabetes mellitus in children <15 years of age (yr) in the Auckland region (New Zealand) over 20 years (1990-2009). We performed a retrospective review of all patients <15 yr diagnosed with type 1 diabetes, from an unselected complete regional cohort. There were 884 new cases of type 1 diabetes, and age at diagnosis rose from 7.6 yr in 1990/1 to 8.9 yr in 2008/9 (r(2) = 0.31, p = 0.009). There was a progressive increase in type 1 diabetes incidence among children <15 yr (p<0.0001), reaching 22.5 per 100,000 in 2009. However, the rise in incidence did not occur evenly among age groups, being 2.5-fold higher in older children (10-14 yr) than in the youngest group (0-4 yr). The incidence of new cases of type 1 diabetes was highest in New Zealand Europeans throughout the study period in all age groups (p<0.0001), but the rate of increase was similar in New Zealand Europeans and Non-Europeans. Type 1 diabetes incidence and average annual increase were similar in both sexes. There was no change in BMI SDS shortly after diagnosis, and no association between BMI SDS and age at diagnosis. There has been a steady increase in type 1 diabetes incidence among children <15 yr in Auckland over 20 years. Contrary to other studies, age at diagnosis has increased and the greatest rise in incidence occurred in children 10-14 yr. There was little change in BMI SDS in this population, providing no support for the 'accelerator hypothesis'.

  5. Late Holocene intensification of the westerly winds at the subantarctic Auckland Islands (51° S), New Zealand

    NASA Astrophysics Data System (ADS)

    Browne, Imogen M.; Moy, Christopher M.; Riesselman, Christina R.; Neil, Helen L.; Curtin, Lorelei G.; Gorman, Andrew R.; Wilson, Gary S.

    2017-10-01

    The Southern Hemisphere westerly winds (SHWWs) play a major role in controlling wind-driven upwelling of Circumpolar Deep Water (CDW) and outgassing of CO2 in the Southern Ocean, on interannual to glacial-interglacial timescales. Despite their significance in the global carbon cycle, our understanding of millennial- and centennial-scale changes in the strength and latitudinal position of the westerlies during the Holocene (especially since 5000 yr BP) is limited by a scarcity of palaeoclimate records from comparable latitudes. Here, we reconstruct middle to late Holocene SHWW variability using a fjord sediment core collected from the subantarctic Auckland Islands (51° S, 166° E), located in the modern centre of the westerly wind belt. Changes in drainage basin response to variability in the strength of the SHWW at this latitude are interpreted from downcore variations in magnetic susceptibility (MS) and bulk organic δ13C and atomic C / N, which monitor influxes of lithogenous and terrestrial vs. marine organic matter, respectively. The fjord water column response to SHWW variability is evaluated using benthic foraminifer δ18O and δ13C, both of which are influenced by the isotopic composition of shelf water masses entering the fjord. Using these data, we provide marine and terrestrial-based evidence for increased wind strength from ˜ 1600 to 900 yr BP at subantarctic latitudes that is broadly consistent with previous studies of climate-driven vegetation change at the Auckland Islands. Comparison with a SHWW reconstruction using similar proxies from Fiordland suggests a northward migration of the SHWW over New Zealand during the first half of the last millennium. Comparison with palaeoclimate and palaeoceanographic records from southern South America and West Antarctica indicates a late Holocene strengthening of the SHWW after ˜ 1600 yr BP that appears to be broadly symmetrical across the Pacific Basin. Contemporaneous increases in SHWW at localities on either

  6. Multi-criteria correlation of tephra deposits to source centres applied in the Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Hopkins, Jenni L.; Wilson, Colin J. N.; Millet, Marc-Alban; Leonard, Graham S.; Timm, Christian; McGee, Lucy E.; Smith, Ian E. M.; Smith, Euan G. C.

    2017-07-01

    Linking tephras back to their source centre(s) in volcanic fields is crucial not only to reconstruct the eruptive history of the volcanic field but also to understand tephra dispersal patterns and thus the potential hazards posed by a future eruption. Here we present a multi-disciplinary approach to correlate distal basaltic tephra deposits from the Auckland Volcanic Field (AVF) to their source centres using proximal whole-rock geochemical signatures. In order to achieve these correlations, major and trace element tephra-derived glass compositions are compared with published and newly obtained whole-rock geochemical data for the entire field. The results show that incompatible trace element ratios (e.g. (Gd/Yb)N, (La/Yb)N, (Zr/Yb)N) vary widely across the AVF (e.g. (La/Yb)N = 5 to 40) but show a more restricted range within samples from a single volcanic centre (e.g. (La/Yb)N = 5 to 10). These ratios are also the least affected by fractional crystallisation and are therefore the most appropriate geochemical tools for correlation between tephra and whole-rock samples. However, findings for the AVF suggest that each volcanic centre does not have a unique geochemical signature in the field as a whole, thus preventing unambiguous correlation of tephras to source centre using geochemistry alone. A number of additional criteria are therefore combined to further constrain the source centres of the distal tephras including age, eruption scale, and location (of centres, and sites where tephra were sampled). The combination of tephrostratigraphy, 40Ar/39Ar dating and morphostratigraphic constraints allow, for the first time, the relative and absolute ordering of 48 of 53 volcanic centres of the Auckland Volcanic Field to be resolved. Eruption frequencies are shown to vary between 0.13 and 1.5 eruptions/kyr and repose periods between individual eruptions vary from <0.1 to 13 kyr, with 23 of the 48 centres shown to have pre-eruptive repose periods of <1000 years. No spatial

  7. Africa's Great Lakes in peril

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ryan, J.C.

    Three of the great lakes in East Africa are in serious danger. Over the last two decades, overfishing, pollution, and the introduction of the Nile perch, have combined to push into extinction as many as 200 fish species found in Lake Victoria. The recycling of nutrients and oxygen through living and non-living matter has been disrupted and large area of the lake are now depleted of oxygen. Overfishing has had dramatic consequences in Lake Malawi, while Lake Tanganyika's most serious problem is with sedimentation from raw sewage, soil and chemicals. International cooperation will be required to restore these lakes.

  8. 33 CFR 162.132 - Connecting waters from Lake Huron to Lake Erie; communications rules.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... monitor: (1) Channel 11 (156.55 mhz) between Lake Huron Cut Lighted Buoy 11 and Lake St. Clair Light; and (2) Channel 12 (156.60 mhz) between Lake St. Clair Light and Detroit River Light. (b) Radiotelephone... Cut Light “7” Lake Huron Cut Lighted Buoy “1” Report. Report St. Clair/Black River Junction Light...

  9. RAINBOW LAKE WILDERNESS AND FLYNN LAKE WILDERNESS STUDY AREA, WISCONSIN.

    USGS Publications Warehouse

    Cannon, W.F.; Dunn, Maynard L.

    1984-01-01

    The Rainbow Lake Wilderness and Flynn Lake Wilderness study area in Wisconsin are contiguous and were studied as a unit. The rainbow Lake Wilderness contains a demonstrated resource of about 210,000 tons of commercial-quality peat in an area of substantiated peat resource potential. The Flynn Lake Wilderness study area contains a demonstrated resource of about 300,000 tons of commercial-quality peat in an area of substantiated peat resource potential. These deposits, however, are of limited importance because larger deposits of similar material are abundant outside the areas, closer to present markets. Rocks in the subsurface contain a low-grade copper resource identified by mining company exploration drilling. Although this is an area of substantiated copper resource potential, it is a low-grade resource, thin and generally at great depth.

  10. Diabetes self-management education in South Auckland, New Zealand, 2007-2008.

    PubMed

    Silva, Martha; Clinton, Janet; Appleton, Sarah; Flanagan, Pat

    2011-03-01

    Self-management education programs seek to help patients realize that they are their own principal caregivers and that health care professionals are consultants who support them in this role. The aim of this study was to evaluate a diabetes self-management education program implemented as part of a district-wide approach in South Auckland, New Zealand, which has some of the highest prevalence rates for diabetes and is one of the most ethnically diverse and deprived regions of New Zealand. Self-management attitudes and behaviors were monitored with the use of questionnaires before and after program implementation. Clinical outcomes such as hemoglobin A1c, body mass index, and blood pressure were also tracked before the program began and 3 months after the program ended. Participant focus groups and facilitator interviews were conducted to explore perceptions of the program. Participants showed improvement in attitudes toward their own ability to manage their diabetes; in diet, physical activity, and foot care; and in hemoglobin A1c levels 3 months after the end of participation. Participants also reduced their sense of isolation when dealing with their diabetes. However, catering to the needs of a multiethnic community is extremely resource-intensive because of the need to provide adequate language and cultural interpretation. Self-management education can work in multiethnic, high-needs communities in New Zealand. Programs must ensure they enable the appropriate mechanisms and have appropriate resources to support the community's needs.

  11. Egg thiamine status of Lake Ontario salmonines 1995-2004 with emphasis on lake trout

    USGS Publications Warehouse

    Fitzsimons, J.D.; Williston, B.; Williston, G.; Brown, L.; El-Shaarawi, A.; Vandenbyllaardt, L.; Honeyfeld, D.; Tillitt, D.; Wolgamood, M.; Brown, S.B.

    2007-01-01

    Alewives (Alosa pseudoharengus), the major prey fish for Lake Ontario, contain thiaminase. They are associated with development of a thiamine deficiency in salmonines which greatly increases the potential for developing an early mortality syndrome (EMS). To assess the possible effects of thiamine deficiency on salmonine reproduction we measured egg thiamine concentrations for five species of Lake Ontario salmonines. From this we estimated the proportion of families susceptible to EMS based on whether they were below the ED20, the egg thiamine concentration associated with 20% mortality due to EMS. The ED20s were 1.52, 2.63, and 2.99 nmol/g egg for Chinook salmon (Oncorhynchus tshawytscha), lake trout (Salvelinus namaycush), and coho salmon (Oncorhynchus kisutch), respectively. Based on the proportion of fish having egg thiamine concentrations falling below the ED20, the risk of developing EMS in Lake Ontario was highest for lake trout, followed by coho (O. kisutch), and Chinook salmon, with the least risk for rainbow trout (O. mykiss). For lake trout from western Lake Ontario, mean egg thiamine concentration showed significant annual variability during 1994 to 2003, when the proportion of lake trout at risk of developing EMS based on ED20 ranged between 77 and 100%. Variation in the annual mean egg thiamine concentration for western Lake Ontario lake trout was positively related (p < 0.001, r2 = 0.94) with indices of annual adult alewife biomass. While suggesting the possible involvement of density-dependent changes in alewives, the changes are small relative to egg thiamine concentrations when alewife are not part of the diet and are of insufficient magnitude to allow for natural reproduction by lake trout.

  12. Lake Generated Microseisms at Yellowstone Lake as a Record of Ice Phenology

    NASA Astrophysics Data System (ADS)

    Mohd Mokhdhari, A. A.; Koper, K. D.; Burlacu, R.

    2017-12-01

    It has recently been shown that wave action in lakes produces microseisms, which generate noise peaks in the period range of 0.8-1.2 s as recorded by nearby seismic stations. Such noise peaks have been observed at seven seismic stations (H17A, LKWY, B208, B944, YTP, YLA, and YLT) located within 2 km of the Yellowstone Lake shoreline. Initial work using 2016 data shows that the variations in the microseism signals at Yellowstone Lake correspond with the freezing and thawing of lake ice: the seismic noise occurs more frequently in the spring, summer, and fall, and less commonly in the winter. If this can be confirmed, then lake-generated microseisms could provide a consistent measure of the freezing and melting dates of high-latitude lakes in remote areas. The seismic data would then be useful in assessing the effects of climate change on the ice phenology of those lakes. In this work, we analyze continuous seismic data recorded by the seven seismic stations around Yellowstone Lake for the years of 1995 to 2016. We generate probability distribution functions of power spectral density for each station to observe the broad elevation of energy near a period of 1 s. The time dependence of this 1-s seismic noise energy is analyzed by extracting the power spectral density at 1 s from every processed hour. The seismic observations are compared to direct measurements of the dates of ice-out and freeze-up as reported by rangers at Yellowstone National Park. We examine how accurate the seismic data are in recording the freezing and melting of Yellowstone Lake, and how the accuracy changes as a function of the number of stations used. We also examine how sensitive the results are to the particular range of periods that are analyzed.

  13. Characterization and comparison of phytoplankton in selected lakes of five Great Lakes area national parks

    USGS Publications Warehouse

    Nevers, Meredith Becker; Whitman, Richard L.

    2004-01-01

    Phytoplankton species have been widely used as indicators of lake conditions, and they may be useful for detecting changes in overall lake condition. In an attempt to inventory and monitor its natural resources, the National Park Service wants to establish a monitoring program for aquatic resources in the Great Lakes Cluster National Parks. This study sought to establish baseline information on the phytoplankton and water chemistry of selected lakes in five national parks in a preliminary effort toward establishing a long-term monitoring program. Phytoplankton and water chemistry samples were collected from ten lakes in five national parks over a two-year period. A total of 176 taxa were identified during the study. Northern lakes generally had higher Shannon-Wiener diversity and clustered together in similarity. Lakes exhibited a south to north gradient of many water chemistry variables, with northern lakes having lower hardness, sulfate, turbidity, and temperature and higher dissolved oxygen. Chloride and sulfate concentrations were the variables that best explained variation among phytoplankton in the ten lakes. A monitoring plan will have to incorporate the differences among lakes, but by coordinating the effort, comparisons within and among parks and other regions will prove useful for determining environmental change.

  14. Monitoring climate signal transfer into the varved lake sediments of Lake Czechowskie, Poland

    NASA Astrophysics Data System (ADS)

    Groß-Schmölders, Miriam; Ott, Florian; Brykała, Dariusz; Gierszewski, Piotr; Kaszubski, Michał; Kienel, Ulrike; Brauer, Achim

    2015-04-01

    In 2012 we started a monitoring program at Lake Czechowskie, Poland, because the lake comprises a long Holocene time series of calcite varves until recent times. The aim of the program is to understand how environmental and climatic conditions influence the hydrological conditions and, ultimately, the sediment deposition processes of the lake. Lake Czechowskie is located in the north of Poland in the Pomeranian Lake District and is part of the national park Tuchola Forest. The landscape and the lake is formed by the glacier retreat after the last glaciation (Weichselian). Lake Czechowskie is a typical hardwater lake and has a length of 1.4 km, an average width of 600 m and a lake surface area of ca 4 km. The maximum depth of 32 m is reached in a rather small hollow in the eastern part of the lake. Two different types of sediment traps provide sediment samples with monthly resolution from different water depths (12m, 26m). In addition, hydrological data including water temperature in different depths, water inflow, throughflow and outflow and the depth of visibility are measured. These data allow to describe strength and duration of lake mixing in spring and autumn and its influence on sedimentation. The sediment samples were analyzed with respect to their dry weight (used to calculate mean daily sediment flux), their inorganic and organic carbon contents, the stable C- and O-isotopes of organic matter and calcite as well as N-isotopes of organic matter. For selected samples dominant diatom taxa are determined. Our first results demonstrate the strong influence of the long winter with ice cover until April in 2013 on the sedimentation. A rapid warming in only 9 days starting on April 9th from -0,3 C° to 15,2 C° resulted in fast ice break-up and a short but intensive lake mixing. In consequence of this short mixing period a strong algal bloom especially of Fragilaria and Crysophycea commenced in April and had its maximum in May. This bloom further induced biogenic

  15. Salinity and hydrology of closed lakes

    USGS Publications Warehouse

    Langbein, Walter Basil

    1961-01-01

    Lakes without outlets, called closed lakes, are exclusively features of the arid and semiarid zones where annual evaporation exceeds rainfall. The number of closed lakes increases with aridity, so there are relatively few perennial closed lakes, but "dry" lakes that rarely contain water are numerous.Closed lakes fluctuate in level to a much greater degree than the open lakes of the humid zone, because variations in inflow can be compensated only by changes in surface area. Since the variability of inflow increases with aridity, it is possible to derive an approximate relationship for the coefficient of variation of lake area in terms of data on rates of evaporation, lake area, lake depth, and drainage area.The salinity of closed lakes is highly variable, ranging from less than 1 percent to over 25 percent by weight of salts. Some evidence suggests that the tonnage of salts in a lake solution is substantially less than the total input of salts into the lake over the period of existence of the closed lake. This evidence suggests further that the salts in a lake solution represent a kind of long-term balance between factors of gain and loss of salts from the solution.Possible mechanisms for the loss of salts dissolved in the lake include deposition in marginal bays, entrapment in sediments, and removal by wind. Transport of salt from the lake surface in wind spray is also a contributing, but seemingly not major, factor.The hypothesis of a long-term balance between input to and losses from the lake solution is checked by deriving a formula for the equilibrium concentration and comparing the results with the salinity data. The results indicate that the reported salinities seemingly can be explained in terms of their geometric properties and hydrologic environment.The time for accumulation of salts in the lake solution the ratio between mass of salts in the solution and the annual input may also be estimated from the geometric and hydrologic factors, in the absence of

  16. Crater Lake revealed

    USGS Publications Warehouse

    Ramsey, David W.; Dartnell, Peter; Bacon, Charles R.; Robinson, Joel E.; Gardner, James V.

    2003-01-01

    Around 500,000 people each year visit Crater Lake National Park in the Cascade Range of southern Oregon. Volcanic peaks, evergreen forests, and Crater Lake’s incredibly blue water are the park’s main attractions. Crater Lake partially fills the caldera that formed approximately 7,700 years ago by the eruption and subsequent collapse of a 12,000-foot volcano called Mount Mazama. The caldera-forming or climactic eruption of Mount Mazama drastically changed the landscape all around the volcano and spread a blanket of volcanic ash at least as far away as southern Canada.Prior to the climactic event, Mount Mazama had a 400,000 year history of cone building activity like that of other Cascade volcanoes such as Mount Shasta. Since the climactic eruption, there have been several less violent, smaller postcaldera eruptions within the caldera itself. However, relatively little was known about the specifics of these eruptions because their products were obscured beneath Crater Lake’s surface. As the Crater Lake region is still potentially volcanically active, understanding past eruptive events is important to understanding future eruptions, which could threaten facilities and people at Crater Lake National Park and the major transportation corridor east of the Cascades.Recently, the lake bottom was mapped with a high-resolution multibeam echo sounder. The new bathymetric survey provides a 2m/pixel view of the lake floor from its deepest basins virtually to the shoreline. Using Geographic Information Systems (GIS) applications, the bathymetry data can be visualized and analyzed to shed light on the geology, geomorphology, and geologic history of Crater Lake.

  17. Lake Sarez, Tajikistan

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Lake Sarez (top), deep in the Pamir mountains of Tajikistan, was created 90 years ago when a strong earthquake triggered a massive landslide that, in turn, became a huge dam along the Murghob River, now called the Usoi Dam. The resulting lake is perched above surrounding drainages at an elevation greater than 3000m, and is part of the watershed that drains the towering Akademi Nauk Range (see the regional image, lower). The lake is 61 km long and as deep as 500 m, and holds an estimated 17 cubic km of water. The area experiences considerable seismic activity, and scientists fear that part of the right bank may slump into the lake, creating a huge wave that will top over and possibly breach the natural dam. Such a wave would create a catastrophic flood downstream along the Bartang, Panj and Amu Darya Rivers, perhaps reaching all the way to the Aral Sea. Currently, central Asian governments, as well as the World Bank and the UN are monitoring the dam closely, and have proposed gradually lowering the lake level as a preventive measure. More information about the lake is available at the following web sites: Lake Sarez Study group, UN Report, Reliefweb Digital photograph numbers ISS002-E-7771 and ISS002-E-7479 were taken in the spring of 2001 from Space Station Alpha and are provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth.

  18. ATMOSPHERIC MERCURY DEPOSITION TO LAKE MICHIGAN DURING THE LAKE MICHIGAN MASS BALANCE STUDY

    EPA Science Inventory

    Wet and dry mercury (Hg) deposition were calculated to Lake Michigan using a hybrid receptor modeling framework. The model utilized mercury monitoring data collected during the Lake Michigan Mass Balance Study and the Atmospheric Exchange Over Lakes and Oceans Study together w...

  19. The Great Lakes' regional climate regimes

    NASA Astrophysics Data System (ADS)

    Sugiyama, Noriyuki

    For the last couple of decades, the Great Lakes have undergone rapid surface warming. In particular, the magnitude of the summer surface-warming trends of the Great Lakes have been much greater than those of surrounding land (Austin and Colman, 2007). Among the Great Lakes, the deepest Lake Superior exhibited the strongest warming trend in its annual, as well as summer surface water temperature. We find that many aspects of this behavior can be explained in terms of the tendency of deep lakes to exhibit multiple regimes characterized, under the same seasonally varying forcing, by the warmer and colder seasonal cycles exhibiting different amounts of wintertime lake-ice cover and corresponding changes in the summertime lake-surface temperatures. In this thesis, we address the problem of the Great Lakes' warming using one-dimensional lake modeling to interpret diverse observations of the recent lake behavior. (Abstract shortened by ProQuest.).

  20. Characterization of lake water and ground water movement in the littoral zone of Williams Lake, a closed-basin lake in North central Minnesota

    USGS Publications Warehouse

    Schuster, P.F.; Reddy, M.M.; LaBaugh, J.W.; Parkhurst, R.S.; Rosenberry, D.O.; Winter, T.C.; Antweiler, Ronald C.; Dean, W.E.

    2003-01-01

    Williams Lake, Minnesota is a closed-basin lake that is a flow-through system with respect to ground water. Ground-water input represents half of the annual water input and most of the chemical input to the lake. Chemical budgets indicate that the lake is a sink for calcium, yet surficial sediments contain little calcium carbonate. Sediment pore-water samplers (peepers) were used to characterize solute fluxes at the lake-water-ground-water interface in the littoral zone and resolve the apparent disparity between the chemical budget and sediment data. Pore-water depth profiles of the stable isotopes ??18O and ??2H were non-linear where ground water seeped into the lake, with a sharp transition from lake-water values to ground-water values in the top 10 cm of sediment. These data indicate that advective inflow to the lake is the primary mechanism for solute flux from ground water. Linear interstitial velocities determined from ??2H profiles (316 to 528 cm/yr) were consistent with velocities determined independently from water budget data and sediment porosity (366 cm/yr). Stable isotope profiles were generally linear where water flowed out of the lake into ground water. However, calcium profiles were not linear in the same area and varied in response to input of calcium carbonate from the littoral zone and subsequent dissolution. The comparison of pore-water calcium profiles to pore-water stable isotope profiles indicate calcium is not conservative. Based on the previous understanding that 40-50 % of the calcium in Williams Lake is retained, the pore-water profiles indicate aquatic plants in the littoral zone are recycling the retained portion of calcium. The difference between the pore-water depth profiles of calcium and ??18O and ??2H demonstrate the importance of using stable isotopes to evaluate flow direction and source through the lake-water-ground-water interface and evaluate mechanisms controlling the chemical balance of lakes. Published in 2003 by John Wiley

  1. LakeVOC; A Deterministic Model to Estimate Volatile Organic Compound Concentrations in Reservoirs and Lakes

    USGS Publications Warehouse

    Bender, David A.; Asher, William E.; Zogorski, John S.

    2003-01-01

    This report documents LakeVOC, a model to estimate volatile organic compound (VOC) concentrations in lakes and reservoirs. LakeVOC represents the lake or reservoir as a two-layer system and estimates VOC concentrations in both the epilimnion and hypolimnion. The air-water flux of a VOC is characterized in LakeVOC in terms of the two-film model of air-water exchange. LakeVOC solves the system of coupled differential equations for the VOC concentration in the epilimnion, the VOC concentration in the hypolimnion, the total mass of the VOC in the lake, the volume of the epilimnion, and the volume of the hypolimnion. A series of nine simulations were conducted to verify LakeVOC representation of mixing, dilution, and gas exchange characteristics in a hypothetical lake, and two additional estimates of lake volume and MTBE concentrations were done in an actual reservoir under environmental conditions. These 11 simulations showed that LakeVOC correctly handled mixing, dilution, and gas exchange. The model also adequately estimated VOC concentrations within the epilimnion in an actual reservoir with daily input parameters. As the parameter-input time scale increased (from daily to weekly to monthly, for example), the differences between the measured-averaged concentrations and the model-estimated concentrations generally increased, especially for the hypolimnion. This may be because as the time scale is increased from daily to weekly to monthly, the averaging of model inputs may cause a loss of detail in the model estimates.

  2. Is Lake Chabot Eutrophic?

    NASA Astrophysics Data System (ADS)

    Pellegrini, K.; Logan, J.; Esterlis, P.; Lew, A.; Nguyen, M.

    2013-12-01

    Introduction/Abstract: Lake Chabot is an integral part of the East Bay watershed that provides habitats for animals and recreation for humans year-round. Lake Chabot has been in danger of eutrophication due to excessive dumping of phosphorous and nitrogen into the water from the fertilizers of nearby golf courses and neighboring houses. If the lake turned out to be eutrophified, it could seriously impact what is currently the standby emergency water supply for many Castro Valley residents. Eutrophication is the excessive richness of nutrients such as nitrogen and phosphorus in a lake, usually as a result of runoff. This buildup of nutrients causes algal blooms. The algae uses up most of the oxygen in the water, and when it dies, it causes the lake to hypoxify. The fish in the lake can't breathe, and consequently suffocate. Other oxygen-dependant aquatic creatures die off as well. Needless to say, the eutrophication of a lake is bad news for the wildlife that lives in or around it. The level of eutrophication in our area in Northern California tends to increase during the late spring/early summer months, so our crew went out and took samples of Lake Chabot on June 2. We focused on the area of the lake where the water enters, known on the map as Honker Bay. We also took readings a ways down in deeper water for comparison's sake. Visually, the lake looked in bad shape. The water was a murky green that glimmered with particulate matter that swirled around the boat as we went by. In the Honker Bay region where we focused our testing, there were reeds bathed in algae that coated the surface of the lake in thick, swirling patterns. Surprisingly enough, however, our test results didn't reveal any extreme levels of phosphorous or nitrogen. They were slightly higher than usual, but not by any significant amount. The levels we found were high enough to stimulate plant and algae growth and promote eutrophication, but not enough to do any severe damage. After a briefing with a

  3. The New Injury Severity Score Versus the Injury Severity Score in Predicting Patient Outcome: A Comparative Evaluation on Trauma Service Patients of the Auckland Hospital

    PubMed Central

    Samin, Oliver A.; Civil, Ian D.

    1999-01-01

    Retrospectively calculated NISS was compared with the prospectively calculated ISS from data derived from the trauma registry of the Trauma Services of the Auckland Hospital as to which test is a better predictor of patient outcome, which is defined as the likelihood of death. The area under the curve (AUC) for ISS and NISS were computed using the non-parametric approach. AUC for ISS = 0.95835, and AUC for NISS = 0.97350, p <0.012. Misclassification rate for ISS was 2.77% and the value for NISS was 2.43%.

  4. Cooperative science to inform Lake Ontario management: Research from the 2013 Lake Ontario CSMI program

    USGS Publications Warehouse

    Watkins, James M.; Weidel, Brian C.; Fisk, Aaron T.; Rudstam, Lars G.

    2017-01-01

    Since the mid-1970s, successful Lake Ontario management actions including nutrient load and pollution reductions, habitat restoration, and fish stocking have improved Lake Ontario. However, several new obstacles to maintenance and restoration have emerged. This special issue presents management-relevant research from multiple agency surveys in 2011 and 2012 and the 2013 Cooperative Science and Monitoring Initiative (CSMI), that span diverse lake habitats, species, and trophic levels. This research focused on themes of nutrient loading and fate; vertical dynamics of primary and secondary production; fish abundance and behavior; and food web structure. Together these papers identify the status of many of the key drivers of the Lake Ontario ecosystem and contribute to addressing lake-scale questions and management information needs in Lake Ontario and the other Great Lakes and connecting water bodies.

  5. Sedimentary and Volcanic Records of the Laschamp and Mono Lake Excursions from Australia and New Zealand

    NASA Astrophysics Data System (ADS)

    Ingham, E. M.; Roberts, A. P.; Turner, G. M.; Heslop, D.; Ronge, T.; Conway, C.; Leonard, G.; Townsend, D.; Tiedemann, R.; Lamy, F.; Calvert, A. T.

    2014-12-01

    Geomagnetic excursions are short-lived deviations of the geomagnetic field from the normal range of secular variation. Despite significant advances in geomagnetic excursion research over the past 20 years, fundamental questions remain concerning the typical duration and global morphology of excursional geomagnetic fields. To answer such questions, more high-resolution, chronologically well-constrained excursion records are required, particularly from the Southern Hemisphere. We present preliminary paleomagnetic records of the Laschamp (~41 ka) and Mono Lake (~35 ka) excursions from three marine sediment cores from the Bounty Trough, New Zealand margin, and complementary volcanic records of the Laschamp excursion from lavas of Mt Ruapehu, New Zealand. Relatively high sedimentation rates of 12 - 26 cm/kyr in the Bounty Trough during glacial periods allow identification of excursional field behavior at each of the studied core locations. Each core displays one or two excursional events, with rapid directional swings between stable normal polarity and reversed excursional directions, each associated with coincident relative paleointensity minima. These anomalous paleomagnetic directions are interpreted to represent the Laschamp and Mono Lake excursions, based on a combination of tephrochronology, radiocarbon dating, and cyclostratigraphy (defined from core-scanning X-ray fluorescence and magnetic susceptibility records). Beside these records, we present results from fourteen lava flows, on Mt Ruapehu, for which 40Ar-39Ar dating indicates ages of between 39 and 45 ka. The step heating 40Ar-39Ar experiments produced particularly flat age plateaus, with corresponding 2 s.d. errors mostly approaching 1 kyr. The youngest and oldest flows carry normal polarity magnetization, however six flows, dated between 41 and 43 ka, display transitional field characteristics. Three of these flows display a declination swing of around 180o, which coincides with a previously published

  6. Hydrology of the Reelfoot Lake basin, Obion and Lake counties, northwestern Tennessee

    USGS Publications Warehouse

    Robbins, C.H.

    1985-01-01

    Nine maps describe the following water resources aspects of the Reelfoot Lake watershed: Map 1-Surface water gaging stations, lake level, and locations of observation wells, rainfall stations and National Weather Service rainfall stations; Maps 2 and 3-water level contours, river stage, groundwater movement; Maps 4 and 5-grid blocks simulating constant head on the Mississippi River, Reelfoot Lake, Running Reelfoot Bayou, Reelfoot Creek, and Running Slough; Maps 6 and 7-difference between model calculated and observed water levels; and Maps 8 and 9-line of equal groundwater level increase and approximate lake area at pool elevation. (Lantz-PTT)

  7. Dendrochronology and lakes: using tree-rings of alder to reconstruct lake levels

    NASA Astrophysics Data System (ADS)

    van der Maaten, Ernst; Buras, Allan; Scharnweber, Tobias; Simard, Sonia; Kaiser, Knut; Lorenz, Sebastian; van der Maaten-Theunissen, Marieke; Wilmking, Martin

    2014-05-01

    Climate change is considered a major threat for ecosystems around the world. Assessing its effects is challenging, amongst others, as we are unsure how ecosystems may respond to climate conditions they were not exposed to before. However, increased insight may be obtained by analyzing responses of ecosystems to past climate variability. In this respect, lake ecosystems appear as valuable sentinels, because they provide direct and indirect indicators of change through effects of climate. Lake-level fluctuations of closed catchments, for example, reflect a dynamic water balance, provide detailed insight in past moisture variations, and thereby allow for assessments of effects of anticipated climate change. Up to now, lake-level data are mostly obtained from gauging records and reconstructions from sediments and landforms. However, these records are in many cases only available over relatively short time periods, and, since geoscientific work is highly demanding, lake-level reconstructions are lacking for many regions. Here, we present and discuss an alternative method to reconstruct lake levels, which is based on tree-ring data of black alder (Alnus glutinosa L.). This tree species tolerates permanently waterlogged and temporally flooded conditions (i.e. riparian vegetation), and is often found along lakeshores. As the yearly growth of trees varies depending upon the experienced environmental conditions, annual rings of black alder from lakeshore vegetation likely capture information on variations in water table, and may therefore be used to reconstruct lake levels. Although alder is a relatively short-lived tree species, the frequent use of its' decay-resistant wood in foundations of historical buildings offers the possibility of extending living tree-chronologies back in time for several centuries. In this study, the potential to reconstruct lake-level fluctuations from tree-ring chronologies of black alder is explored for three lake ecosystems in the Mecklenburg

  8. Postnatal depressive symptoms among Pacific mothers in Auckland: prevalence and risk factors.

    PubMed

    Abbott, Max W; Williams, Maynard M

    2006-03-01

    To assess the prevalence of and risk factors for postnatal depressive symptoms in a cohort of mothers of Pacific Island infants in Auckland, New Zealand. The data were gathered as part of the Pacific Island Families Study, in which 1376 mothers were interviewed when their babies were 6 weeks old. The interview included the Edinburgh Postnatal Depression Scale (EPDS). 16.4% of mothers were assessed as probably experiencing depression. Prevalence rates varied from 7.6% for Samoans to 30.9% for Tongans. In addition to ethnicity, risk factors identified by stepwise multiple logistic regression included low Pacific Island acculturation, first birth, stress due to insufficient food, household income less than dollar 40,000, difficulty with transport, dissatisfaction with pregnancy, birth experience, baby's sleep patterns, partner relationship and home. A large prevalence difference between Tongans and other groups remained when the effects of other risk factors were controlled statistically. The prevalence of depressive symptoms among Pacific mothers is at the upper end of the range typically reported. Focus on the overall rate, however, obscures substantial variation between groups. Risk factors are generally similar to those identified in previous research. The findings have implications for prevention and treatment and caution against assuming homogeneity within ethnic categories. Further research is required to explain differences in prevalence between Tongan and other Pacific Island groups.

  9. Sexual difference in PCB concentrations of lake trout (Salvelinus namaycush) from Lake Ontario

    USGS Publications Warehouse

    Madenjian, Charles P.; Keir, Michael J.; Whittle, D. Michael; Noguchi, George E.

    2010-01-01

    We determined polychlorinated biphenyl (PCB) concentrations in 61 female lake trout (Salvelinus namaycush) and 71 male lake trout from Lake Ontario (Ontario, Canada and New York, United States). To estimate the expected change in PCB concentration due to spawning, PCB concentrations in gonads and in somatic tissue of lake trout were also determined. In addition, bioenergetics modeling was applied to investigate whether gross growth efficiency (GGE) differed between the sexes. Results showed that, on average, males were 22% higher in PCB concentration than females in Lake Ontario. Results from the PCB determinations of the gonads and somatic tissues revealed that shedding of the gametes led to 3% and 14% increases in PCB concentration for males and females, respectively. Therefore, shedding of the gametes could not explain the higher PCB concentration in male lake trout. According to the bioenergetics modeling results, GGE of males was about 2% higher than adult female GGE, on average. Thus, bioenergetics modeling could not explain the higher PCB concentrations exhibited by the males. Nevertheless, a sexual difference in GGE remained a plausible explanation for the sexual difference in PCB concentrations of the lake trout.

  10. Historical evidence for discrete stocks of lake trout (Salvelinus namaycush) in Lake Michigan

    USGS Publications Warehouse

    Brown, Edward H.; Eck, G.W.; Foster, N.R.; Horrall, R.M.; Coberly, C.E.

    1981-01-01

    Although few biological data exist on the now extinct native lake trout, Salvelinus namaycush, of Lake Michigan, historical records and interviews with former commercial fishermen strongly suggest that this once widespread resource was composed of a number of discrete spawning populations or stocks. A natural division of the resource into distinct stocks is consistent with the size of Lake Michigan and its varied physiography. The native trout may have undergone subtle genetic changes over the millennia, although we cannot determine whether the physical and behavioral differences represented different genotypes or only temporary effects of the local environment. Because of physiographic similarities among the upper Great Lakes and probable interchanges of lake trout during the last glacial period, we recommend that progeny of extant wild stocks, particularly from Lake Superior, are genetically most suitable for recolonizing Lake Michigan. Moreover, the hatchery-held parents of such fish should be infused periodically with genes of the wild or feral donor populations. Despite the sound historical basis for these recommendations, we also recognize that sufficiently high stocking rates coupled with a reduction of heavy exploitation may be even more important than heritability in obtaining self-sustaining populations.

  11. Lake Mead, NV

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Lake Mead, Nevada, (36.0N, 114.5E) where the water from the Colorado River empties after it's 273 mile journey through the Grand Canyon of Arizona is the subject of this photo. Other features of interest are Hoover Dam on the south shore of Lake Mead where cheap hydroelectric power is secondary to the water resources made available in this northern desert region and the resort city of Las Vegas, just to the west of Lake Mead.

  12. Loktak Lake, India

    NASA Image and Video Library

    2018-04-13

    Loktak Lake is the largest freshwater lake in northeast India, and is famous for the floating "phudmis," masses of vegetation, soil and organic material. The lake is a source of water for hydropower, irrigation, drinking water, and livelihood for fish farmers. The image was acquired March 19, 2018, covers an area of 20.5 by 27.3 kilometers, and is located at 24.5 degrees north, 93.8 degrees east. https://photojournal.jpl.nasa.gov/catalog/PIA22369

  13. Authigenic carbonate precipitation in Lake Acigöl, a hypersaline lake in southwestern Turkey

    NASA Astrophysics Data System (ADS)

    Balci, Nurgul; Menekse, Meryem; Gül Karagüler, Nevin; Seref Sönmez, M.; Meister, Patrick

    2014-05-01

    Lake Acigöl (Bitter Lake) is a hypersaline lake in southwestern Turkey at an elevation of 836 m above sea level showing authigenic precipitation of several different carbonate mineral phases. It is a perennial lake and closed drainage basin where a semiarid continental climate dominates. Due to the extreme water chemistry (salinity 8-200 mg/l; SO4 112-15232 mg/l; Cl 290-35320 mg/l; Mg, 82-3425 mg/l; Ca 102-745 mg/l) unique microorganisms flourish in the lake. We studied microbial diversity from enrichment cultures and performed precipitation experiments using similar water chemistry and adding bacterial enrichment cultures from lake sediments in order to elucidate whether the mineral assemblages found in the lake can be reproduced. Experiments using moderately halophilic bacteria obtained from the lake sediments demonstrate the formation of various calcium-/magnesium-carbonates: hydromagnesite, dypingite, huntite, monohydrocalcite and aragonite. The relative amounts of different mineral phases, particularly monohydrocalcite, hydromagnesite and dypingite, could be controlled by varying the sulphate concentration in the media from 0 to 56 mM. The similar mineral assemblages identified in the sediments of Lake Acigöl and in the experiments point to similar thermodynamic conditions and kinetics of crystal growth. In particular, the similar spherical morphology points to a rapid crystal growth under strong kinetic inhibition, possibly by organic polymers that are commonly produced by microbial communities. Our results demonstrate that the authigenic carbonate paragenesis of hypersaline lakes as Lake Acigöl can be reproduced in halophilic bacterial cultures. The exact thermodynamic conditions and precipitation kinetics under seasonally changing water chemistry or in batch experiment, however, still have to be constrained in order to establish a microbial model for carbonate precipitation in such environments.

  14. Mathematics Education in the South Pacific. Proceedings of the Annual Conference of the Mathematics Education Research Group of Australasia Incorporated (25th, Auckland, New Zealand, July 7-10, 2002). Volume I [and] Volume II.

    ERIC Educational Resources Information Center

    Barton, Bill, Ed.; Irwin, Kathryn C., Ed.; Pfannkuch, Maxine, Ed.; Thomas, Michael O. J., Ed.

    This document contains the proceedings of the 25th annual conference of the Mathematics Education Research Group of Australia (MERGA) held at the University of Auckland, New Zealand. The focus of this meeting is mathematics education in the South Pacific. Presentations are centered around the topic of numeracy in primary or elementary school.…

  15. Glacial Lake Lind, Wisconsin and Minnesota

    USGS Publications Warehouse

    Johnson, M.D.; Addis, K.L.; Ferber, L.R.; Hemstad, C.B.; Meyer, G.N.; Komai, L.T.

    1999-01-01

    Glacial Lake Lind developed in the pre-late Wisconsinan St. Croix River valley, Minnesota and Wisconsin, and lasted more than 1000 yr during the retreat of the Superior lobe at the end of the Wisconsinan glaciation. Lake Lind sediment consists primarily of red varved silt and clay, but also includes mud-flow deposits, nearshore silt (penecontemporaneously deformed in places), nearshore rippled sand, and deltaic sand. Lake Lind varved red clay is not part of glacial Lake Grantsburg, as suggested by earlier authors, because the red varves are separated from overlying glacial Lake Grantsburg silt and clay by a unit of deltaic and fluvial sand. Furthermore, varve correlations indicate that the base of the red varves is younger to the north, showing that the basin expanded as the Superior lobe retreated and was not a lake basin dammed to the southwest by the advancing Grantsburg sublobe. Varve correlations indicate that the Superior lobe retreated at a rate of about 200 m/yr. Uniform winter-clay thickness throughout most of the varve couplets suggests thermal stratification in the lake with clay trapped in the epilimnion; some clay would exit the lake at the outlet prior to winter freeze. Zones of thicker winter-clay layers, in places associated with mud-flow layers, indicate outlet incision, lake-level fall, and shoreline erosion and resuspension of lake clay. The most likely outlet for glacial Lake Lind was in the southwest part of the lake near the present site of Minneapolis, Minnesota. Nearshore sediment indicates that the lake level of glacial Lake Lind was around 280 m. The elevation of the base of the Lake Lind sediments indicates water depth was 20 to 55 m. Evidence in the southern part of the lake basin suggests that the Superior lobe readvanced at least once during the early stages of glacial Lake Lind. Lake Lind ended not by drainage but by being filled in by prograding deltas and outwash plains composed of sand derived from the retreating Superior lobe. It

  16. Isotope analyses of the lake sediments in the Plitvice Lakes, Croatia

    NASA Astrophysics Data System (ADS)

    Horvatinčić, Nada; Sironić, Andreja; Barešić, Jadranka; Bronić, Ines Krajcar; Nikolov, Jovana; Todorović, Nataša; Hansman, Jan; Krmar, Miodrag

    2014-10-01

    The analyses of radioactive isotopes 14C, 137Cs and 210Pb, and stable isotope 13C were performed in the sediment cores, top 40 cm, taken in 2011 from karst lakes Prošće and Kozjak in the Plitvice Lakes National Park, central Croatia. Frozen sediment cores were cut into 1 cm thick layers and dried. 14C activity in both carbonate and organic fractions was measured using accelerator mass spectrometry technique with graphite synthesis. 137Cs, 210Pb, 214Pb and 214Bi were measured by low level gamma spectrometry method on ORTECHPGe detector with the efficiency of 32%. Distribution of 14C activity from both lakes showed increase of the 14C activity in the top 10-12 cm in both carbonate and organic fractions as a response to thermonuclear bomb-produced 14C in the atmosphere in the sixties of the 20th century. Anthropogenically produced 137Cs was also observed in sediment profiles. Sedimentation rates for both lake sediments were estimated based on the unsupported 210Pb activity. Different 14C activity of the carbonate fraction (63-80 pMC, percent of modern carbon) and organic fraction (82-93 pMC) is the result of geochemical and biological processes of the sediment precipitation in the lake waters. This is also confirmed by the δ 13 C values of both fractions. Carbon isotope composition, a 14 C and δ 13 C, was compared with the lake sediments from the same lakes collected in 1989 and 2003.

  17. Changes in bathymetry for Lake Katherine and Wood Lake, Richland County, South Carolina, 1989-93

    USGS Publications Warehouse

    Patterson, Glenn G.

    1995-01-01

    Bathymetric surveys of Lake Katherine and Wood Lake, small residential lakes in Columbia, South Carolina, were made in 1989 and 1993. During this period the combined volume of the lakes decreased by 519,000 cubic feet (11.9 acre-feet). Most of the decrease in volume occurred in the northern part of Lake Katherine where deltaic sediment deposits at the mouth of Gills Creek increased in thickness during the 4-year period. The sediment was derived from a combination of sources in the Gills Creek Basin upstream from the lakes. Construction of a highway and a housing development in the Basin were significant factors in the sedimentation.

  18. Hydrochemical determination of source water contributions to Lake Lungo and Lake Ripasottile (central Italy)

    USGS Publications Warehouse

    Archer, Claire; Noble, Paula; Kreamer, David; Piscopo, Vincenzo; Petitta, Marco; Rosen, Michael R.; Poulson, Simon R.; Piovesan, Gianluca; Mensing, Scott

    2017-01-01

    Lake Lungo and Lake Ripasottile are two shallow (4-5 m) lakes located in the Rieti Basin, central Italy, that have been described previously as surface outcroppings of the groundwater table. In this work, the two lakes as well as springs and rivers that represent their potential source waters are characterized physio-chemically and isotopically, using a combination of environmental tracers. Temperature and pH were measured and water samples were analyzed for alkalinity, major ion concentration, and stable isotope (δ2H, δ18O, δ13C of dissolved inorganic carbon, and δ34S and δ18O of sulfate) composition. Chemical data were also investigated in terms of local meteorological data (air temperature, precipitation) to determine the sensitivity of lake parameters to changes in the surrounding environment. Groundwater represented by samples taken from Santa Susanna Spring was shown to be distinct with SO42- and Mg2+ content of 270 and 29 mg/L, respectively, and heavy sulfate isotopic composition(δ34S=15.2 ‰ and δ18O=10‰). Outflow from the Santa Susanna Spring enters Lake Ripasottile via a canal and both spring and lake water exhibits the same chemical distinctions and comparatively low seasonal variability. Major ion concentrations in Lake Lungo are similar to the Vicenna Riara Spring and are interpreted to represent the groundwater locally recharged within the plain. The δ13CDIC exhibit the same groupings as the other chemical parameters, providing supporting evidence of the source relationships. Lake Lungo exhibited exceptional ranges of δ13CDIC (±5 ‰) and δ2H, δ18O (±5 ‰ and ±7 ‰, respectively), attributed to sensitivity to seasonal changes. The hydrochemistry results, particularly major ion data, highlight how the two lakes, though geographically and morphologically similar, represent distinct hydrochemical facies. These data also show a different response in each lake to temperature and precipitation patterns in the basin that may be attributed

  19. Water-quality and lake-stage data for Wisconsin lakes, water years 2012–2013

    USGS Publications Warehouse

    Manteufel, S. Bridgett; Robertson, Dale M.

    2017-05-25

    IntroductionThe U.S. Geological Survey (USGS), in cooperation with local and other agencies, collects data at selected lakes throughout Wisconsin. These data, accumulated over many years, provide a data base for developing an improved understanding of the water quality of lakes. To make these data available to interested parties outside the USGS, the data are published annually in this report series. The locations of water-quality and lake-stage stations in Wisconsin for water year 2012 are shown in figure 1. A water year is the 12-month period from October 1 through September 30. It is designated by the calendar year in which it ends. Thus, the period October 1, 2011 through September 30, 2012, is called “water year 2012.”The purpose of this report is to provide information about the chemical and physical characteristics of Wisconsin lakes. Data that have been collected at specific lakes, and information to aid in the interpretation of those data, are included in this report. Data collected include measurements of in-lake water quality and lake stage. Time series of Secchi depths, surface total phosphorus and chlorophyll a concentrations collected during non-frozen periods are included for all lakes. Graphs of vertical profiles of temperature, dissolved oxygen, pH, and specific conductance are included for sites where these parameters were measured. Descriptive information for each lake includes: location of the lake, area of the lake’s watershed, period for which data are available, revisions to previously published records, and pertinent remarks. Additional data, such as streamflow and water quality in tributary and outlet streams of some of the lakes, are published online at http://nwis.waterdata.usgs.gov/wi/nwis.Water-resources data, including stage and discharge data at most streamflow-gaging stations, are available online. The Wisconsin Water Science Center’s home page is at https://www.usgs.gov/centers/wisconsin-water-science-center. Information on

  20. National Lakes Assessment 2012: A Collaborative Survey of Lakes in the United States

    EPA Science Inventory

    The National Lakes Assessment 2012: A Collaborative Survey of Lakes in the United States presents the results of a second evaluation of the lakes in the United States. This report is part of the National Aquatic Resource Surveys, a series of statistically based surveys designed t...

  1. Lake trout (Salvelinus namaycush) suppression for bull trout (Salvelinus confluentus) recovery in Flathead Lake, Montana, North America

    USGS Publications Warehouse

    Hansen, Michael J.; Hansen, Barry S; Beauchamp, David A.

    2016-01-01

    Non-native lake trout Salvelinus namaycush displaced native bull trout Salvelinus confluentus in Flathead Lake, Montana, USA, after 1984, when Mysis diluviana became abundant following its introduction in upstream lakes in 1968–1976. We developed a simulation model to determine the fishing mortality rate on lake trout that would enable bull trout recovery. Model simulations indicated that suppression of adult lake trout by 75% from current abundance would reduce predation on bull trout by 90%. Current removals of lake trout through incentivized fishing contests has not been sufficient to suppress lake trout abundance estimated by mark-recapture or indexed by stratified-random gill netting. In contrast, size structure, body condition, mortality, and maturity are changing consistent with a density-dependent reduction in lake trout abundance. Population modeling indicated total fishing effort would need to increase 3-fold to reduce adult lake trout population density by 75%. We conclude that increased fishing effort would suppress lake trout population density and predation on juvenile bull trout, and thereby enable higher abundance of adult bull trout in Flathead Lake and its tributaries.

  2. Evidence of widespread natural reproduction by lake trout Salvelinus namaycush in the Michigan waters of Lake Huron

    USGS Publications Warehouse

    Riley, S.C.; He, J.X.; Johnson, J.E.; O'Brien, T. P.; Schaeffer, J.S.

    2007-01-01

    Localized natural reproduction of lake trout Salvelinus namaycush in Lake Huron has occurred since the 1980s near Thunder Bay, Michigan. During 2004–2006, USGS spring and fall bottom trawl surveys captured 63 wild juvenile lake trout at depths ranging from 37–73 m at four of five ports in the Michigan waters of the main basin of Lake Huron, more than five times the total number captured in the previous 30-year history of the surveys. Relatively high catches of wild juvenile lake trout in bottom trawls during 2004–2006 suggest that natural reproduction by lake trout has increased and occurred throughout the Michigan waters of the main basin. Increased catches of wild juvenile lake trout in the USGS fall bottom trawl survey were coincident with a drastic decline in alewife abundance, but data were insufficient to determine what mechanism may be responsible for increased natural reproduction by lake trout. We recommend further monitoring of juvenile lake trout abundance and research into early life history of lake trout in Lake Huron.

  3. Satellite monitoring of dramatic changes at Hawai'i's only alpine lake: Lake Waiau on Mauna Kea volcano

    USGS Publications Warehouse

    Patrick, Matthew R.; Kauahikaua, James P.

    2015-01-01

    Lake Waiau is a small, typically 100-meter-long lake, located near the summit of Mauna Kea volcano, on the Island of Hawaiʻi. It is Hawaiʻi’s only alpine lake and is considered sacred in Hawaiian cultural tradition. Over the past few years, the lake has diminished in size, and, by October 2013, surface water had almost completely disappeared from the lake. In this study, we use high-resolution satellite images and aerial photographs to document recent changes at the lake. Based on our reconstructions covering the past 200 years, the historical lake surface area has typically ranged from 5,000 to 7,000 square meters, but in 2010 a dramatic plunge in lake area ensued. The lake area rebounded significantly in early 2014, following heavy winter storms. This near disappearance of the lake, judging from analysis of visitor photographs and field reports, appears to be highly unusual, if not unprecedented, in the historical record. The unusually low water levels in the lake are consistent with a recent severe drought in Hawaiʻi.

  4. Implementing and sustaining a hand hygiene culture change programme at Auckland District Health Board.

    PubMed

    Roberts, Sally A; Sieczkowski, Christine; Campbell, Taima; Balla, Greg; Keenan, Andrew

    2012-05-11

    In January 2009 Auckland District Health Board commenced implementation of the Hand Hygiene New Zealand (HHNZ) programme to bring about a culture change and to improve hand hygiene compliance by healthcare workers. We describe the implementation process and assess the effectiveness of this programme 36 months after implementation. In keeping with the HHNZ guideline the implementation was divided into five steps: roll-out and facility preparation, baseline evaluation, implementation, follow-up evaluation and sustainability. The process measure was improvement in hand hygiene compliance and the outcome measure was Staphylococcus aureus clinical infection and bacteraemia rates. The mean (95% CI; range) baseline compliance rates for the national reporting wards was 35% (95% CI 24-46%, 25-61%). The overall compliance by the 7th audit period was 60% (95% CI 46-74; range 47-91). All healthcare worker groups had improvement in compliance. The reduction in healthcare-associated S. aureus bacteraemia rates following the implementation was statistically significant (p=0.027). Compliance with hand hygiene improved following implementation of a culture change programme. Sustaining this improvement requires commitment and strong leadership at a senior level both nationally and within each District Health Board.

  5. Prevalence and predictors of 6-month fatigue in patients with ischemic stroke: a population-based stroke incidence study in Auckland, New Zealand, 2002-2003.

    PubMed

    Feigin, Valery L; Barker-Collo, Suzanne; Parag, Varsha; Hackett, Maree L; Kerse, Ngaire; Barber, P Alan; Theadom, Alice; Krishnamurthi, Rita

    2012-10-01

    Although persistent and significant fatigue affects the daily life of stroke survivors, there are no population-based studies examining the prevalence of fatigue in 6-month survivors of ischemic stroke and few studies of predictors of poststroke fatigue. This article examined data from the Auckland Regional Community Stroke study conducted in Auckland, New Zealand, in 2002 to 2003. Presence of fatigue was evaluated at 6 months in 613 patients with ischemic stroke using a Short Form 36 Vitality Score (energy and fatigue) of ≤ 47. Multivariate logistic regression analysis was used to determine predictors of fatigue development 6 months poststroke. The prevalence of fatigue was 30% (28% in men and 33% in women). There was a clear association between increased prevalence of fatigue and advancing age. The only baseline variables independently associated with an increased risk of developing fatigue at 6 months poststroke were prestroke incontinence and being of New Zealand European ethnicity. Being independent and living alone at baseline were associated with significant reduction in the risk of being fatigued at 6 months poststroke. Severe depression at 6 months was significantly and independently associated with being fatigued. The prevalence of fatigue found in our study is at the lower level of range reported in other studies. The prevalence of fatigue increased with advancing age, as found in most previous studies. Because fatigue can have a negative impact on stroke recovery, particular attention needs to be paid to those who are older, incontinent before stroke, and those who report severe symptoms of depression at 6 months after stroke.

  6. Block Slides on Extremely Weak Tectonic Clay Seams in Openly Folded Tertiary Mud-Rocks at Auckland and the Rangitikei Valley, North Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Prebble, Warwick M.; Williams, Ann L.

    2016-06-01

    Block slides have developed on extremely weak, thin clay seams of tectonic origin, parallel to bedding in gently dipping sandstones and mudstones of Tertiary age. Two areas of noted instability are investigated at Auckland and the Rangitikei valley. Dimensions range from 100 m across × 100 m long for short displacement block slides up to 4 km across × 3 km long for large landslide complexes in which block slides are a major component. Displacements of blocks range from incipient (cm) through short (30 m) to 2 or 3 km for large slides. Many of the Auckland slides are dormant but likely to move in a 2000 year return period earthquake or 100 year high intensity rain storm. At Rangitikei there are many active, younger slides. Sliding rates for active failures vary from a few cm/year to 50 m in 30 min. Host rocks are weak to very weak clayey sandstones and sandy mudstones. The seams are rich in smectite. They have polished and crushed walls, may have slickensides and some contain rounded rock fragments. Laboratory shear strength of the seams is 13 kPa cohesion and 13° friction, with a lower bound of 8° at zero cohesion. Strength is increased at the field scale by waviness, steps and splays. Continuity can be demonstrated over distances of hundreds of metres. Key investigation methods were mapping, shafts and trenches. Tectonic uplift, folding and faulting of the weak Tertiary strata and river down-cutting are perpetuating block slide development.

  7. Lake Huron LAMPs

    EPA Pesticide Factsheets

    The approach in Lake Huron differs from the Lakewide Management Plans of the other Great Lakes: no formal binational designation of lakewide beneficial use impairments, nor extensive lakewide modeling of chemical loadings

  8. Great Lakes: Chemical Monitoring

    ERIC Educational Resources Information Center

    Delfino, Joseph J.

    1976-01-01

    The Tenth Great Lakes Regional Meeting of the American Chemical Society met to assess current Chemical Research activity in the Great Lakes Basin, and addressed to the various aspects of the theme, Chemistry of the Great Lakes. Research areas reviewed included watershed studies, atmospheric and aquatic studies, and sediment studies. (BT)

  9. The lakes of Titan

    USGS Publications Warehouse

    Stofan, E.R.; Elachi, C.; Lunine, J.I.; Lorenz, R.D.; Stiles, B.; Mitchell, K.L.; Ostro, S.; Soderblom, L.; Wood, C.; Zebker, H.; Wall, S.; Janssen, M.; Kirk, R.; Lopes, R.; Paganelli, F.; Radebaugh, J.; Wye, L.; Anderson, Y.; Allison, M.; Boehmer, R.; Callahan, P.; Encrenaz, P.; Flamini, E.; Francescetti, G.; Gim, Y.; Hamilton, G.; Hensley, S.; Johnson, W.T.K.; Kelleher, K.; Muhleman, D.; Paillou, P.; Picardi, G.; Posa, F.; Roth, L.; Seu, R.; Shaffer, S.; Vetrella, S.; West, R.

    2007-01-01

    The surface of Saturn's haze-shrouded moon Titan has long been proposed to have oceans or lakes, on the basis of the stability of liquid methane at the surface. Initial visible and radar imaging failed to find any evidence of an ocean, although abundant evidence was found that flowing liquids have existed on the surface. Here we provide definitive evidence for the presence of lakes on the surface of Titan, obtained during the Cassini Radar flyby of Titan on 22 July 2006 (T16). The radar imaging polewards of 70?? north shows more than 75 circular to irregular radar-dark patches, in a region where liquid methane and ethane are expected to be abundant and stable on the surface. The radar-dark patches are interpreted as lakes on the basis of their very low radar reflectivity and morphological similarities to lakes, including associated channels and location in topographic depressions. Some of the lakes do not completely fill the depressions in which they lie, and apparently dry depressions are present. We interpret this to indicate that lakes are present in a number of states, including partly dry and liquid-filled. These northern-hemisphere lakes constitute the strongest evidence yet that a condensable-liquid hydrological cycle is active in Titan's surface and atmosphere, in which the lakes are filled through rainfall and/or intersection with the subsurface 'liquid methane' table. ??2007 Nature Publishing Group.

  10. Description of the University of Auckland Global Mars Mesoscale Meteorological Model (GM4)

    NASA Astrophysics Data System (ADS)

    Wing, D. R.; Austin, G. L.

    2005-08-01

    The University of Auckland Global Mars Mesoscale Meteorological Model (GM4) is a numerical weather prediction model of the Martian atmosphere that has been developed through the conversion of the Penn State University / National Center for Atmospheric Research fifth generation mesoscale model (MM5). The global aspect of this model is self consistent, overlapping, and forms a continuous domain around the entire planet, removing the need to provide boundary conditions other than at initialisation, yielding independence from the constraint of a Mars general circulation model. The brief overview of the model will be given, outlining the key physical processes and setup of the model. Comparison between data collected from Mars Pathfinder during its 1997 mission and simulated conditions using GM4 have been performed. Diurnal temperature variation as predicted by the model shows very good correspondence with the surface truth data, to within 5 K for the majority of the diurnal cycle. Mars Viking Data is also compared with the model, with good agreement. As a further means of validation for the model, various seasonal comparisons of surface and vertical atmospheric structure are conducted with the European Space Agency AOPP/LMD Mars Climate Database. Selected simulations over regions of interest will also be presented.

  11. Trialling a shaken baby syndrome prevention programme in the Auckland District Health Board.

    PubMed

    Kelly, Patrick; Wilson, Kati; Mowjood, Aqeela; Friedman, Joshua; Reed, Peter

    2016-02-19

    To describe and evaluate a shaken baby prevention programme trialled in the Auckland District Health Board from January 2010, to December 2011. Development and implementation of the programme, telephone survey of a sample of caregivers and written survey of a sample of providers. At least 2,592 caregivers received the trial programme. 150 (6%) were surveyed by telephone a median of 6 weeks later. 128 (85%) remembered at least one key message, unprompted; most commonly "It's OK to walk away" (94/150, 63%). When asked, 92% had made a plan for what to do when frustrated and 63% had shared the information with others. Only 98/150 (65%) watched the programme DVD. Many said they already knew about the risks of shaking a baby, but still found the programme highly relevant. Thirty-one nurses were surveyed. There was a high degree of agreement that the programme was relevant. Barriers to programme delivery included time, workload and the documentation required. A shaken baby prevention programme adapted to New Zealand can be introduced in a District Health Board and is acceptable to caregivers and health professionals. Further research is needed to evaluate the content, mode of delivery and effectiveness of this programme.

  12. Occurrence, spatiotemporal distribution, and ecological risks of steroids in a large shallow Chinese lake, Lake Taihu.

    PubMed

    Zhou, Li-Jun; Zhang, Bei-Bei; Zhao, Yong-Gang; Wu, Qinglong L

    2016-07-01

    Steroids have been frequently detected in surface waters, and might pose adverse effects on aquatic organisms. However, little information is available regarding the occurrence and spatiotemporal distribution of steroids in lake environments. In addition to pollution sources, the occurrence and spatiotemporal distribution of steroids in lake environments might be related to lake types (shallow or deep), lake hydrodynamics, and sorption-desorption processes in the water-sediment systems. In this study, the occurrence, spatiotemporal distribution, and ecological risks of 36 steroids in a large shallow lake were evaluated by investigating surface water and sediment samples at 32 sites in Lake Taihu over two seasons. Twelve and 15 analytes were detected in aqueous and sedimentary phases, respectively, with total concentrations ranging from 0.86 to 116ng/L (water) and from 0.82 to 16.2ng/g (sediment, dry weight). Temporal variations of steroid concentrations in the water and sediments were statistically significant, with higher concentrations in winter. High concentrations of steroids were found in the seriously polluted bays rather than in the pelagic zone of the lake. Strong lake currents might mix pelagic waters, resulting in similar concentrations of steroids in the pelagic zone. Mass balance analysis showed that sediments in shallow lakes are in general an important sink for steroids. Steroids in the surface water and sediments of Lake Taihu might pose potential risks to aquatic organisms. Overall, our study indicated that the concentrations and spatiotemporal distribution of steroids in the large shallow lake are influenced simultaneously by pollution sources and lake hydrodynamics. Steroids in the large shallow Lake Taihu showed clear temporal and spatial variations and lake sediments may be a potential sink of steroids. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Pyroclastic Density Current Hazards in the Auckland Volcanic Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Brand, B. D.; Gravley, D.; Clarke, A. B.; Bloomberg, S. H.

    2012-12-01

    The most dangerous phenomena associated with phreatomagmatic eruptions are dilute pyroclastic density currents (PDCs). These are turbulent, ground-hugging sediment gravity currents that travel radially away from the explosive center at up to 100 m/s. The Auckland Volcanic Field (AVF), New Zealand, consists of approximately 50 eruptive centers, at least 39 of which have had explosive phreatomagmatic behaviour. A primary concern for future AVF eruptions is the impact of dilute PDCs in and around the Auckland area. We combine field observations from the Maungataketake tuff ring, which has one of the best exposures of dilute PDC deposits in the AVF, with a quantitative model for flow of and sedimentation from a radially-spreading, steady-state, depth-averaged dilute PDC (modified from Bursik and Woods, 1996 Bull Volcanol 58:175-193). The model allows us to explore the depositional mechanisms, macroscale current dynamics, and potential impact on societal infrastructure of dilute PDCs from a future AVF eruption. The lower portion of the Maungataketake tuff ring pyroclastic deposits contains trunks, limbs and fragments of Podocarp trees (<1 m in diameter) that were blown down by dilute PDCs up to 0.7-0.9 km from the vent. Beyond this trees were encapsulated and buried in growth position up to the total runout distance of 1.6-1.8 km. This observation suggests that the dynamic pressure of the current quickly dropped as it travelled away from source. Using the tree diameter and yield strength of the wood, we calculate that dynamic pressures (Pdyn) of 10-75 kPa are necessary to topple trees of this size and composition. Thus the two main criteria for model success based on the field evidence include (a) Pdyn must be >10 kPa nearer than 0.9 km to the vent, and <10 kPa beyond 0.9 km, and (b) the total run-out distance must be between 1.6 and 1.8 km. Model results suggest the two main forces controlling the runout distance and Pdyn over the extent of the current are

  14. Diet of lake trout and burbot in northern Lake Michigan during spring: Evidence of ecological interaction

    USGS Publications Warehouse

    Jacobs, Gregory R.; Madenjian, Charles P.; Bunnell, David B.; Holuszko, Jeffrey D.

    2010-01-01

    We used analyses of burbot (Lota lota) and lake trout (Salvelinus namaycush) diets taken during spring gill-net surveys in northern Lake Michigan in 2006-2008 to investigate the potential for competition and predator-prey interactions between these two species. We also compared our results to historical data from 1932. During 2006-2008, lake trout diet consisted mainly of alewives (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax), whereas burbot utilized a much wider prey base including round goby (Neogobius melanostomus), rainbow smelt, alewives, and sculpins. Using the Schoener's diet overlap index, we found a higher potential for interspecific competition in 1932 than in 2006-2008, though diet overlap was not significant in either time period. No evidence of cannibalism by lake trout or lake trout predation on burbot was found in either time period. In 2006-2008, however, lake trout composed 5.4% (by weight) of burbot diet. To determine whether this predation could be having an impact on lake trout rehabilitation efforts in northern Lake Michigan, we developed a bioenergetic-based consumption estimate for burbot on Boulder Reef (a representative reef within the Northern Refuge) and found that burbot alone can consume a considerable proportion of the yearling lake trout stocked annually, depending on burbot density. Overall, we conclude that predation, rather than competition, is the more important ecological interaction between burbot and lake trout, and burbot predation may be contributing to the failed lake trout rehabilitation efforts in Lake Michigan.

  15. 33 CFR 162.220 - Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Mohave (Colorado River), Ariz.-Nev. 162.220 Section 162.220 Navigation and Navigable Waters COAST GUARD... REGULATIONS § 162.220 Hoover Dam, Lake Mead, and Lake Mohave (Colorado River), Ariz.-Nev. (a) Lake Mead and... the axis of Hoover Dam and that portion of Lake Mohave (Colorado River) extending 4,500 feet...

  16. Great Minds? Great Lakes!

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Chicago, IL. Great Lakes National Program Office.

    This book contains lesson plans that provide an integrated approach to incorporating Great Lakes environmental issues into elementary subjects. The book is divided into three subject areas: (1) History, which includes the origins of the Great Lakes, Great Lakes people, and shipwrecks; (2) Social Studies, which covers government, acid rain as a…

  17. A case-control study of Yersinia enterocolitica infections in Auckland.

    PubMed

    Satterthwaite, P; Pritchard, K; Floyd, D; Law, B

    1999-10-01

    To identify major risk factors for Yersinia enterocolitica (YE) and identify measures to reduce YE infections. A prospective case control study, group age matched, using 186 cases of YE identified by community pathology laboratories and 379 randomly selected controls. Conducted between April 1995 and June 1996 in Auckland, New Zealand. Face-to-face interviews used a standardised questionnaire examining exposures to factors potentially associated with YE infections including untreated water, unreticulated sewerage, consumption of selected foods, selected food handling practices and socio-demographic factors. Multivariate logistic regression was used to calculate adjusted odds ratios for the potential risk factors. Population attributable risk (PAR) was calculated for significant exposures. Having more than two people living in the home was more common among cases than controls (OR = 2.2). Town supply water (OR = 0.2), reticulated sewerage (OR = 0.34) and looking after a young child (OR = 0.51) were significantly less common. Of the meats, only pork (OR = 1.34) had a higher consumption rate, while bacon (OR = 0.75) and smallgoods (OR = 0.73) were consumed less frequently by cases than controls. Eating food from a sandwich bar was more frequent among cases (OR = 1.18). Fruit and vegetable consumption was marginally less (OR = 0.98). The population attributable risk of these factors was 0.89, implying that 89% of YE would be eliminated if adverse exposures were removed. The risk of YE illness is increased by contact with untreated water, unreticulated sewerage and consumption of pork. Investigation of non-town water supply, informal sewerage systems and methods of preparation and consumption of pork are recommended to determine how YE enters the human food chain.

  18. Great Salt Lake Microbial Communities: The Foundation of a Terminal Lake Ecosystem

    NASA Astrophysics Data System (ADS)

    Baxter, B. K.; Acord, M.; Riddle, M. R.; Avery, B.

    2006-12-01

    Great Salt Lake (GSL) is a natural hypersaline ecosystem and a terminal lake of substantial size. The dramatic fluctuation in water levels and salinity creates an ecological backdrop selective for organisms with a high degree of adaptability. At the macro level, the biodiversity of the GSL ecosystem is simple, due to the limitations of an extreme saline environment: Birds eat the two invertebrates of the lake, and the invertebrates eat phytoplankton. However, analysis of the microbial level reveals an enormous diversity of species interacting with one another and the ecosystem as a whole. Our cultivation, biochemical tests, microscopy and DNA sequencing yielded data on dozens of isolates. These data demonstrate novel species, and possibly genera, living in the lake. In addition, we have discovered viruses (bacteriophage) that prey on the microorganisms. Preliminary data on bacteria dwelling in the gut of the brine shrimp, Artemia franciscana, link these prokaryotic organisms to the food chain for the first time. All of these results taken together open the door for the discussion of the significance of the microbial level of terminal lake ecosystem, particularly in light of lake water contamination and bioremediation possibilities.

  19. Palaeolimnological evidence of vulnerability of Lake Neusiedl (Austria) toward climate related changes since the last "vanished-lake" stage.

    NASA Astrophysics Data System (ADS)

    Tolotti, Monica; Milan, Manuela; Boscaini, Adriano; Soja, Gerhard; Herzig, Alois

    2013-04-01

    The palaeolimnological reconstruction of secular evolution of Euroepan Lakes with key socio-economical relevance respect to large (climate change) and local scale (land use, tourism) environmental changes, represents one of the objectives of the project EuLakes (European Lakes Under Environmental Stressors, Supporting lake governance to mitigate the impact of climate change, Reg. N. 2CE243P3), launched in 2010 within the Central European Inititiative. The project consortium comprises lakes of different morphology and prevalent human uses, including the meso-eutrophic Lake Neusiedl, the largest Austrian lake (total area 315 km2), and the westernmost shallow (mean depth 1.2 m) steppe lake of the Euro-Asiatic continent. The volume of Lake Neusiedl can potentially change over the years, in relation with changing balance between atmospheric precipitation and lake water evapotranspiration. Changing water budget, together with high lake salinity and turbidity, have important implications over the lake ecosystem. This contribution illustrates results of the multi-proxi palaeolimnological reconstruction of ecologial changes occurred in Lake Neusiedl during the last ca. 140 years, i.e. since the end of the last "vanished-lake" stage (1865-1871). Geochemical and biological proxies anticipate the increase in lake productivity of ca. 10 years (1950s) respect to what reported in the literature. Diatom species composition indicate a biological lake recovery in the late 1980s, and suggest a second increment in lake productivity since the late 1990s, possibly in relation with the progressive increase in the nitrogen input from agriculture. Abundance of diatoms typical of brackish waters indicated no significant long-term change in lake salinity, while variations in species toleranting dessiccation confirm the vulnerability of Lake Neusiedl toward climate-driven changes in the lake water balance. This fragility is aggravated by the the semi-arid climate conditions of the catchemnt

  20. Geography of Alaska Lake Districts: Identification, Description, and Analysis of Lake-Rich Regions of a Diverse and Dynamic State

    USGS Publications Warehouse

    Arp, Christopher D.; Jones, Benjamin M.

    2009-01-01

    Lakes are abundant landforms and important ecosystems in Alaska, but are unevenly distributed on the landscape with expansive lake-poor regions and several lake-rich regions. Such lake-rich areas are termed lake districts and have landscape characteristics that can be considered distinctive in similar respects to mountain ranges. In this report, we explore the nature of lake-rich areas by quantitatively identifying Alaska's lake districts, describing and comparing their physical characteristics, and analyzing how Alaska lake districts are naturally organized and correspond to climatic and geophysical characteristics, as well as studied and managed by people. We use a digital dataset (National Hydrography Dataset) of lakes greater than 1 hectare, which includes 409,040 individual lakes and represents 3.3 percent of the land-surface area of Alaska. The selection criteria we used to identify lake districts were (1) a lake area (termed limnetic ratio, in percent) greater than the mean for the State, and (2) a lake density (number of lakes per unit area) greater than the mean for the State using a pixel size scaled to the area of interest and number of lakes in the census. Pixels meeting these criteria were grouped and delineated and all groups greater than 1,000 square kilometers were identified as Alaska's lake districts. These lake districts were described according to lake size-frequency metrics, elevation distributions, geology, climate, and ecoregions to better understand their similarities and differences. We also looked at where lake research and relevant ecological monitoring has occurred in Alaska relative to lake districts and how lake district lands and waters are currently managed. We identified and delineated 20 lake districts in Alaska representing 16 percent of the State, but including 65 percent of lakes and 75 percent of lake area. The largest lake districts identified are the Yukon-Kuskokwim Delta, Arctic Coastal Plain, and Iliamna lake districts with

  1. ARE LAKES GETTING WARMER? REMOTE SENSING OF LARGE LAKE TEMPERATURES

    EPA Science Inventory

    Recent studies (Levitus et al., 2000) suggest a warning of the world ocean over the past 50 years. Freshwater lakes could also be getting warmer but thermal measurements to determine this are lacking. Large lake temperatures are vertically and horizontally heterogeneous and vary ...

  2. L-Lake macroinvertebrate community

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Specht, W.L.

    1996-06-01

    To characterize the present benthic macroinvertebrate community of L-Lake, Regions 5 and 7 of the reservoir were sampled in September 1995 at the same locations sampled in 1988 and 1989 during the L-Lake monitoring program. The macroinvertebrate community of 1995 is compared to that of 1988 and 1989. The species composition of L-Lake`s macroinvertebrate community has changed considerably since 1988-1989, due primarily to maturation of the reservoir ecosystem. L-Lake contains a reasonably diverse macroinvertebrate community that is capable of supporting higher trophic levels, including a diverse assemblage of fish species. The L-Lake macroinvertebrate community is similar to those of manymore » other southeastern reservoirs, and there is no indication that the macroinvertebrate community is perturbed by chemical or physical stressors.« less

  3. Water-quality and lake-stage data for Wisconsin lakes, water years 2008−2011

    USGS Publications Warehouse

    Manteufel, S. Bridgett; Olson, Daniel L.; Robertson, Dale M.; Goddard, Gerald L.

    2016-09-30

    The U.S. Geological Survey (USGS), in cooperation with local and other agencies, collects data at selected lakes throughout Wisconsin. These data, accumulated over many years, provide a data base for developing an improved understanding of the water quality of lakes. To make these data available to interested parties outside the USGS, the data are published annually in this report series.The purpose of this report is to provide information about the chemical and physical characteristics of Wisconsin lakes during water years 2008–2011. A water year is the 12-month period from October 1 through September 30. It is designated by the calendar year in which it ends. Thus, the period October 1, 2007 through September 30, 2008 is called "water year 2008." Data that have been collected at specific lakes, and information to aid in the interpretation of those data, are presented in this report for water years from 2008–2011. Data collected include measurements of in-lake water quality and lake stage. Time series of Secchi depths, surface total phosphorus and chlorophyll a concentrations collected during non-frozen periods are included for all lakes. Graphs of vertical profiles of temperature, dissolved oxygen, pH, and specific conductance are included for sites where these parameters were measured. Descriptive information for each lake includes: location of the lake, area of the lake’s watershed, period for which data are available, revisions to previously published records, and pertinent remarks. Additional data, such as streamflow and water quality in tributary and outlet streams of some of the lakes, are available via the "USGS Annual Water Data Report" Web site: http://wdr.water.usgs.gov/.

  4. Hydrological and solute budgets of Lake Qinghai, the largest lake on the Tibetan Plateau

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jin, Zhangdong; You, Chen-Feng; Wang, Yi

    2009-12-04

    Water level and chemistry of Lake Qinghai are sensitive to climate changes and are important for paleoclimatic implications. An accurate understanding of hydrological and chemical budgets is crucial for quantifying geochemical proxies and carbon cycle. Published results of water budget are firstly reviewed in this paper. Chemical budget and residence time of major dissolved constituents in the lake are estimated using reliable water budget and newly obtained data for seasonal water chemistry. The results indicate that carbonate weathering is the most important riverine process, resulting in dominance of Ca 2+ and DIC for river waters and groundwater. Groundwater contribution tomore » major dissolved constituents is relatively small (4.2 ± 0.5%). Wet atmospheric deposition contributes annually 7.4–44.0% soluble flux to the lake, resulting from eolian dust throughout the seasons. Estimates of chemical budget further suggest that (1) the Buha-type water dominates the chemical components of the lake water, (2) Na +, Cl -, Mg 2+ , and K + in lake water are enriched owing to their conservative behaviors, and (3) precipitation of authigenic carbonates (low-Mg calcite, aragonite, and dolomite) transits quickly dissolved Ca 2+ into the bottom sediments of the lake, resulting in very low Ca 2+ in the lake water. Therefore, authigenic carbonates in the sediments hold potential information on the relative contribution of different solute inputs to the lake and the lake chemistry in the past.« less

  5. An evaluation of lake trout reproductive habitat on Clay Banks Reef, northwestern Lake Michigan

    USGS Publications Warehouse

    Edsall, Thomas A.; Holey, Mark E.; Manny, Bruce A.; Kennedy, Gregory W.

    1995-01-01

    The extinction of the native populations of lake trout (Salvelinus namaycush) in Lake Michigan in about 1956 has been followed by a decades-long attempt to reestablish self-sustaining populations of this valuable species in habitats it formerly occupied throughout the lake. One of the most recent management strategies designed to facilitate recovery was to make a primary management objective the establishment of sanctuaries where stocked lake trout could be protected and self-sustaining populations reestablished. In the present study we employed habitat survey and mapping techniques, field and laboratory bioassays, egg traps, sediment traps, and gill nets to examine the potential for successful natural reproduction by stocked lake trout on Clay Banks Reef in the Door-Kewaunee sanctuary in Wisconsin waters of Lake Michigan. Our study revealed (1) there was suitable habitat on the reef to support the production of viable fry, (2) spawner abundance on the reef was the highest recorded in the great lakes, and (3) eggs taken from spawners on the reef and held on the reef in plexiglas incubators hatched and produced fry that survived through swim-up. We conclude that Clay Banks Reef has the potential to support successful natural reproduction by stocked lake trout.

  6. Ecology of playa lakes

    USGS Publications Warehouse

    Haukos, David A.; Smith, Loren M.

    1992-01-01

    Between 25,000 and 30,000 playa lakes are in the playa lakes region of the southern high plains (Fig. 1). Most playas are in west Texas (about 20,000), and fewer, in New Mexico, Oklahoma, Kansas, and Colorado. The playa lakes region is one of the most intensively cultivated areas of North America. Dominant crops range from cotton in southern areas to cereal grains in the north. Therefore, most of the native short-grass prairie is gone, replaced by crops and, recently, grasses of the Conservation Reserve Program. Playas are the predominant wetlands and major wildlife habitat of the region.More than 115 bird species, including 20 species of waterfowl, and 10 mammal species have been documented in playas. Waterfowl nest in the area, producing up to 250,000 ducklings in wetter years. Dominant breeding and nesting species are mallards and blue-winged teals. During the very protracted breeding season, birds hatch from April through August. Several million shorebirds and waterfowl migrate through the area each spring and fall. More than 400,000 sandhill cranes migrate through and winter in the region, concentrating primarily on the larger saline lakes in the southern portion of the playa lakes region.The primary importance of the playa lakes region to waterfowl is as a wintering area. Wintering waterfowl populations in the playa lakes region range from 1 to 3 million birds, depending on fall precipitation patterns that determine the number of flooded playas. The most common wintering ducks are mallards, northern pintails, green-winged teals, and American wigeons. About 500,000 Canada geese and 100,000 lesser snow geese winter in the playa lakes region, and numbers of geese have increased annually since the early 1980’s. This chapter describes the physiography and ecology of playa lakes and their attributes that benefit waterfowl.

  7. Examining indirect effects of lake trout recovery

    EPA Science Inventory

    With the recovery of lake trout populations in Lake Superior, there are indications of decreased forage fish abundance and density-dependence in lake trout. In Lake Superior, lean lake trout historically occupied depths < 60 m, and siscowet lake trout occupied depths > 60 m...

  8. Hatchery Contributions to Emerging Naturally Produced Lake Huron Lake Trout.

    PubMed

    Scribner, Kim; Tsehaye, Iyob; Brenden, Travis; Stott, Wendylee; Kanefsky, Jeannette; Bence, James

    2018-06-19

    Recent assessments indicate the emergence of naturally produced lake trout (Salvelinus namaycush) recruitment throughout Lake Huron in the North American Laurentian Great Lakes (>50% of fish <7 yrs). Because naturally produced fish derived from different stocked hatchery strains are unmarked, managers cannot distinguish strains contributing to natural recruitment. We used 15 microsatellite loci to identify strains of naturally produced lake trout (N=1567) collected in assessment fisheries during early (2002-2004) and late (2009-2012) sampling periods. Individuals from 13 American and Canadian hatchery strains (N=1143) were genotyped to develop standardized baseline information. Strain contributions were estimated using a Bayesian inferential approach. Deviance information criteria was used to compare models evaluating strain contributions at different spatial and temporal scales. The best performing models were the most complex models, suggesting that hatchery strain contributions to naturally produced lake trout varied spatially among management districts and temporally between time periods. Contributions of Seneca strain lake trout were consistently high across most management districts, with contributions increasing from early to late time periods (estimates ranged from 52-94% for the late period across eight of nine districts). Strain contributions deviated from expectations based on historical stocking levels, indicating strains differed with respect to survival, reproductive success, and/or dispersal. Knowledge of recruitment levels of strains stocked in different management districts, and how strain-specific recruitment varies temporally, spatially, and as a function of local or regional stocking is important to prioritize strains for future stocking and management of the transition process from primarily hatchery to naturally produced stocks.

  9. Introduction to the Proceedings of the 1994 International Conference on Restoration of Lake Trout in the Laurentian Great Lakes

    USGS Publications Warehouse

    Selgeby, James H.

    1995-01-01

    Lake trout (Salvelinus namaycush) restoration in the Great Lakes began in the 1950s when stocking of artificially propagated lake trout was coupled with the first attempts at sea lamprey (Petromyzon marinus) control. A major milestone in the restoration process was recorded when a selective sea lamprey larvicide was identified in 1958 (Applegate et al. 1958) and then applied broad scale in Lake Superior in 1958-60 (Applegate et al. 1961). Other milestones include the expansion of the sea lamprey control programs into Lakes Michigan and Huron in 1960 (sustained usage in Lake Huron began in 1966, Smith and Tibbles 1980), Lake Ontario in 1971-72 (Elrod et al. 1995), and Lake Erie in 1986 (Cornelius et al. 1995). Following the collapse of lake trout in the Great Lakes and the implementation of massive stocking of hatchery-reared fish and effective sea lamprey control, the first documented evidence of nearshore natural reproduction of lake trout was in Lake Superior in 1965 (Dryer and King 1968), in Lake Michigan in 1980 (Jude et al. 1981), in Lake Huron in 1981-82 (Nester and Poe 1984), and in Lake Ontario in 1986 (Marsden et al. 1988).

  10. Influence of geomorphic setting on sedimentation of two adjacent alpine lakes, Triglav Lakes Valley (Julian Alps, NW Slovenia)

    NASA Astrophysics Data System (ADS)

    Smuc, Andrej; Skabene, Dragomir; Muri, Gregor; Vreča, Polona; Jaćimović, Radojko; Čermelj, Branko; Turšič, Janja

    2013-04-01

    The Triglav Lakes Valley is elongated, 7km long depression, located high (at places over 2000 m.a.s.l.) in the central part of the Julian Alps (NW Slovenia). It hosts 6 small isolated lakes that formed due to the combination of Neogene tectonic and Pleistocene glaciation. The study is focused on the 5th and 6th Triglav Valley Lakes that characterize lower part of the valley. The lakes are located so close to each other that they are even connected in times of high water. Thus, they share the same bedrock geology, are subjected to the same climatic forcing and share similar vegetation communities. Despite their proximity, the lakes differ in their hydrologic and geomorphic setting. The lakes have no permanent surface tributaries; however 5th is fed periodically, at times of high water level, by the Močivec spring, while additional water flows from the swamp area near its northern shore. An underground spring on the eastern side of 5th represents the lake's only permanent freshwater inflow, while drainage takes place to the west via a small ponor. 6th has only one weak underground spring on the eastern side of the lake. Water levels may fluctuate between 2 and 3 m. Additionally, the lakes have different configuration of lakes shores; the northern shores of the 5th lake are low-angle soil and debris covered plateau, while southern shores of the 5th lake and shores of the 6th lake are represented by heavily karstified carbonate base rock and covered partly by trees. The detailed sedimentary analysis of the lakes record showed some similarities, but also some significant differences. Sediments of both lakes are represented by fine-grained turbidity current deposits that are transported from lake shores during snow melt or storms. The grain-size and sedimentary rates of the lakes are however markedly different. The 5th lake has coarser grained sediments, with mean ranging from 46 to 60 µm and records higher sedimentation rates of ~0,57 cm/year, compared to the 6th lake

  11. Early observations on an emerging Great Lakes invader Hemimysis anomala in Lake Ontario

    USGS Publications Warehouse

    Walsh, Maureen G.; Lantry, Brian F.; Boscarino, Brent; Bowen, Kelly; Gerlofsma, Jocelyn; Schaner, Ted; Back, Richard; Questel, Jennifer; Smythe, A. Garry; Cap, Roberta; Goehle, Michael; Young, Bryan; Chalupnicki, Marc A.; Johnson, James H.; McKenna, James E.

    2010-01-01

    Hemimysis anomala, a Ponto-Caspian littoral mysid, is an emerging Great Lakes invader that was discovered in Lakes Michigan and Ontario in 2006. Similar to the native mysid Mysis diluviana, Hemimysis exhibits a diel vertical migration pattern but generally inhabits shallower and warmer waters than M. diluviana. Because basic information on the distribution, habitat use, and biology of Hemimysis in the Great Lakes is scarce, the potential for food web disruption by Hemimysis cannot easily be predicted. Preliminary observations indicate widespread invasion of Hemimysis in Lake Ontario. In this study, we confirm the presence of Hemimysis at sites spanning the northern and southern shores of Lake Ontario and the presence of the individuals during winter months. In one horizontal tow in November 2007, over 26,000 individuals were collected with a length range of 4.4 to 9.0. mm and an average caloric density of 611. cal/g wet weight. The most effective methods for sampling Hemimysis were horizontal tows with either a zooplankton net in the water column or a benthic sled near the lake bottom. Although more quantitative data on the life history and distribution of this species is necessary, our preliminary observations support the prediction that the potential for Hemimysis to impact the nearshore food web in Lake Ontario appears high.

  12. Lakes on Titan

    NASA Image and Video Library

    2006-07-24

    The Cassini spacecraft, using its radar system, has discovered very strong evidence for hydrocarbon lakes on Titan. Dark patches, which resemble terrestrial lakes, seem to be sprinkled all over the high latitudes surrounding Titan north pole

  13. Temperature Trends in Montane Lakes

    NASA Astrophysics Data System (ADS)

    Melack, J. M.; Sadro, S.; Jellison, R.

    2014-12-01

    Long-term temperature trends in lakes integrate hydrological and meteorological factors. We examine temperature trends in a small montane lake with prolonged ice-cover and large seasonal snowfall and in a large saline lake. Emerald Lake, located in the Sierra Nevada (California), is representative of high-elevation lakes throughout the region. No significant trend in outflow temperature was apparent from 1991to 2012. Snowfall in the watershed accounted for 93% of the variability in average summer lake temperatures. Mono Lake (California) lies in a closed, montane basin and is hypersaline and monomictic or meromictic. Temperature profiles have been collected from 1982 to 2010. In the upper water column, the July-August-September water temperatures increased 0.8-1.0°C over the 29 years. This rate of warming is less than published estimates based on satellite-derived skin temperatures and will discussed in the context of general limnological interpretation of temperature trends.

  14. Habitat Suitability Index Models: Lake trout (exclusive of the Great Lakes)

    USGS Publications Warehouse

    Marcus, Michael D.; Hubert, Wayne A.; Anderson, Stanley H.

    1984-01-01

    The lake trout is an important commercial and sport fish in North America. In the Central Rocky Mountain regi on, 1ake trout are common ly referred to as "mackinaw". There is good evidence that lake trout should be called "1 ake charr" (Morton 1980). No subspecies of lake trout is presently recognized (Robins et al. 1980). The species, however, has extreme variability throughout its range, making it difficult to draw general conclusions about its biology (Martin and Olver 1980).

  15. Great Lakes in January

    NASA Image and Video Library

    2017-12-08

    This image taken on January 13, 2015 from the Suomi NPP satellite's VIIRS instrument shows the Great Lakes and surrounding areas. The latest Great Lakes Surface Environmental Analysis (GLSEA) from the NOAA Great Lakes Environmental Research Laboratory shows total ice cover of 29.3% as of January 13th. Credit: NOAA/NASA/NPP Via NOAA Environmental Visualization Laboratory

  16. Limnological and water-quality data from Wonder Lake, Chilchukabena Lake, and Lake Minchumina, Denali National Park and Preserve and surrounding area, Alaska, June 2006-August 2008

    USGS Publications Warehouse

    Long, D.A.; Arp, C.D.

    2011-01-01

    Growing visitor traffic and resource use, as well as natural and anthropogenic land and climatic changes, can place increasing stress on lake ecosystems in Denali National Park and Preserve. Baseline data required to substantiate impact assessment in this sub-arctic region is sparse to non-existent. The U.S. Geological Survey, in cooperation with the National Park Service, conducted a water-quality assessment of several large lakes in and around the Park from June 2006 to August 2008. Discrete water-quality samples, lake profiles of pH, specific conductivity, dissolved-oxygen concentration, water temperature, turbidity, and continuous-record temperature profile data were collected from Wonder Lake, Chilchukabena Lake, and Lake Minchumina. In addition, zooplankton, snow chemistry data, fecal coliform, and inflow/outflow water-quality samples also were collected from Wonder Lake.

  17. Wet trend continues for lakes

    NASA Astrophysics Data System (ADS)

    Katzoff, Judith A.

    About 20% of the United States, including the regions of the Great Lakes and the Great Salt Lake, has entered a fourth year of record and near-record streamflow and lake levels, according to the U.S. Geological Survey (USGS). From June 3 until June 8, 1986, the Great Salt Lake stood at 1283.77 m above sea level, 0.076 m above the previous record, which was set in 1873. (Records have been kept for the lake since 1847.) On June 8, a dike south of the lake gave way during a windstorm, causing flooding of evaporation ponds used for mineral recovery.As a result of the breach, the lake's level dropped to 1283.65 m above sea level by June 10 but rose to 1283.68 m by June 20. The latest official reading, made on June 30, showed that the lake's level had dropped to 1283.63 m above sea level. According to Tom Ross, chief of the Current Water Conditions Group at the USGS National Center in Reston, Va., this drop represents “a normal seasonal decline brought on by evaporation.”

  18. Three-Dimensional Simulation of Avalanche-Generated Impulse Waves and Evaluation of Lake-Lowering Scenarios at Lake Palcacocha, Peru

    NASA Astrophysics Data System (ADS)

    Chisolm, R. E.; McKinney, D. C.

    2014-12-01

    Accelerated retreat of Andean glaciers in recent decades due to a warming climate has caused the emergence and growth of glacial lakes. As these lakes continue to grow, they pose an increasing risk of glacial lake outburst floods (GLOFs). GLOFs can be triggered by moraine failures or by avalanches, rockslides, or ice calving into glacial lakes. For many decades Lake Palcacocha in the Cordillera Blanca, Peru has threatened citizens living in the city of Huaraz which was devastated by a GLOF in 1941. A safety system for Lake Palcacocha was put in place in the 1970's to control the lake level, but the lake has since grown to the point where it is once again dangerous. Overhanging ice from the glaciers above and a relatively low freeboard make the lake vulnerable to avalanches and landslides. Lake Palcacocha is used as a case study to investigate the impact of an avalanche event on the lake dynamics. Three-dimensional lake modeling in the context of glacial hazards is not common, but 3D simulations can enhance our understanding of avalanche-generated impulse waves and their downstream impacts. In this work, a 3D hydrodynamic model is used to simulate the generation of an impulse wave from an avalanche falling into the lake, wave propagation, and overtopping of the terminal moraine. These results are used as inputs to a downstream model to predict the impact from a GLOF. As lowering the level of the lake is the most likely mitigation alternative, several scenarios are considered to evaluate the impact from avalanche events with a reduction in the lake level. The results of this work can be used to evaluate the effectiveness of the current lake management system and potential lake-lowering alternatives. Use of a robust 3D lake model enables more accurate predictions of peak flows during GLOF events and the time scales of these events so that mitigation strategies can be developed that reduce the risk to communities living downstream of hazardous lakes.

  19. The Lake-Catchment (LakeCat) Dataset for characterizing hydrologically-relevant landscape features for lakes across the conterminous US

    EPA Science Inventory

    Lake conditions, including their biota, respond to both natural and human-related landscape features. Characterizing these features within the contributing areas (i.e., delineated watersheds) of lakes could improve the analysis and the sustainable use and management of these impo...

  20. The near extinction of lake trout in Lake Michigan

    USGS Publications Warehouse

    Eschmeyer, Paul H.

    1957-01-01

    Comparisons in 1949 and 1950 of numbers of legal-sized lake trout caught in large-mesh nets with numbers of small fish taken in chub nets showed that both large and small lake trout declined over the same period, and that by these years the decline may have been greater among small than among legal-sized fish.

  1. Decline of the world's saline lakes

    NASA Astrophysics Data System (ADS)

    Wurtsbaugh, Wayne A.; Miller, Craig; Null, Sarah E.; Derose, R. Justin; Wilcock, Peter; Hahnenberger, Maura; Howe, Frank; Moore, Johnnie

    2017-11-01

    Many of the world's saline lakes are shrinking at alarming rates, reducing waterbird habitat and economic benefits while threatening human health. Saline lakes are long-term basin-wide integrators of climatic conditions that shrink and grow with natural climatic variation. In contrast, water withdrawals for human use exert a sustained reduction in lake inflows and levels. Quantifying the relative contributions of natural variability and human impacts to lake inflows is needed to preserve these lakes. With a credible water balance, causes of lake decline from water diversions or climate variability can be identified and the inflow needed to maintain lake health can be defined. Without a water balance, natural variability can be an excuse for inaction. Here we describe the decline of several of the world's large saline lakes and use a water balance for Great Salt Lake (USA) to demonstrate that consumptive water use rather than long-term climate change has greatly reduced its size. The inflow needed to maintain bird habitat, support lake-related industries and prevent dust storms that threaten human health and agriculture can be identified and provides the information to evaluate the difficult tradeoffs between direct benefits of consumptive water use and ecosystem services provided by saline lakes.

  2. National Lakes Assessment

    EPA Pesticide Factsheets

    The National Lakes Assessment is a collaborative, statistical survey of the nation's lakes. It is one of four national surveys that EPA and its partners conduct to assess the condition and health of the nation's water resources.

  3. Lake-level history of Lake Michigan for the past 12,000 years: the record from deep lacustrine sediments

    USGS Publications Warehouse

    Colman, Steven M.; Forester, Richard M.; Reynolds, Richard L.; Sweetkind, Donald S.; King, John W.; Gangemi, Paul; Jones, Glenn A.; Keigwin, Loyd D.; Foster, David S.

    1994-01-01

    Collection and analysis of an extensive set of seismic-reflection profiles and cores from southern Lake Michigan have provided new data that document the history of the lake basin for the past 12,000 years. Analyses of the seismic data, together with radiocarbon dating, magnetic, sedimentologic, isotopic, and paleontologic studies of core samples, have allowed us to reconstruct lake-level changes during this recent part of the lake's history.The post-glacial history of lake-level changes in the Lake Michigan basin begins about 11.2 ka with the fall from the high Calumet level, caused by the retreat of the Two Rivers glacier, which had blocked the northern outlet of the lake. This lake-level fall was temporarily reversed by a major influx of water from glacial Lake Agassiz (about 10.6 ka), during which deposition of the distinctive gray Wilmette Bed of the Lake Michigan Formation interrupted deposition of red glaciolacustrine sediment. Lake level then continued to fall, culminating in the opening of the North Bay outlet at about 10.3 ka. During the resulting Chippewa low phase, lake level was about 80 m lower than it is today in the southern basin of Lake Michigan.The rise of the early Holocene lake level, controlled primarily by isostatic rebound of the North Bay outlet, resulted in a prominent, planar, transgressive unconformity that eroded most of the shoreline features below present lake level. Superimposed on this overall rise in lake level, a second influx of water from Lake Agassiz temporarily raised lake levels an unknown amount about 9.1 ka. At about 7 ka, lake level may have fallen below the level of the outlet because of sharply drier climate. Sometime between 6 and 5 ka, the character of the lake changed dramatically, probably due mostly to climatic causes, becoming highly undersaturated with respect to calcium carbonate and returning primary control of lake level to the isostatically rising North Bay outlet. Post-Nipissing (about 5 ka) lake level has

  4. Conifer density within lake catchments predicts fish mercury concentrations in remote subalpine lakes

    USGS Publications Warehouse

    Eagles-Smith, Collin A.; Herring, Garth; Johnson, Branden L.; Graw, Rick

    2016-01-01

    Remote high-elevation lakes represent unique environments for evaluating the bioaccumulation of atmospherically deposited mercury through freshwater food webs, as well as for evaluating the relative importance of mercury loading versus landscape influences on mercury bioaccumulation. The increase in mercury deposition to these systems over the past century, coupled with their limited exposure to direct anthropogenic disturbance make them useful indicators for estimating how changes in mercury emissions may propagate to changes in Hg bioaccumulation and ecological risk. We evaluated mercury concentrations in resident fish from 28 high-elevation, sub-alpine lakes in the Pacific Northwest region of the United States. Fish total mercury (THg) concentrations ranged from 4 to 438 ng/g wet weight, with a geometric mean concentration (±standard error) of 43 ± 2 ng/g ww. Fish THg concentrations were negatively correlated with relative condition factor, indicating that faster growing fish that are in better condition have lower THg concentrations. Across the 28 study lakes, mean THg concentrations of resident salmonid fishes varied as much as 18-fold among lakes. We used a hierarchal statistical approach to evaluate the relative importance of physiological, limnological, and catchment drivers of fish Hg concentrations. Our top statistical model explained 87% of the variability in fish THg concentrations among lakes with four key landscape and limnological variables: catchment conifer density (basal area of conifers within a lake's catchment), lake surface area, aqueous dissolved sulfate, and dissolved organic carbon. Conifer density within a lake's catchment was the most important variable explaining fish THg concentrations across lakes, with THg concentrations differing by more than 400 percent across the forest density spectrum. These results illustrate the importance of landscape characteristics in controlling mercury bioaccumulation in fish.

  5. Conifer density within lake catchments predicts fish mercury concentrations in remote subalpine lakes.

    PubMed

    Eagles-Smith, Collin A; Herring, Garth; Johnson, Branden; Graw, Rick

    2016-05-01

    Remote high-elevation lakes represent unique environments for evaluating the bioaccumulation of atmospherically deposited mercury through freshwater food webs, as well as for evaluating the relative importance of mercury loading versus landscape influences on mercury bioaccumulation. The increase in mercury deposition to these systems over the past century, coupled with their limited exposure to direct anthropogenic disturbance make them useful indicators for estimating how changes in mercury emissions may propagate to changes in Hg bioaccumulation and ecological risk. We evaluated mercury concentrations in resident fish from 28 high-elevation, sub-alpine lakes in the Pacific Northwest region of the United States. Fish total mercury (THg) concentrations ranged from 4 to 438 ng/g wet weight, with a geometric mean concentration (±standard error) of 43 ± 2 ng/g ww. Fish THg concentrations were negatively correlated with relative condition factor, indicating that faster growing fish that are in better condition have lower THg concentrations. Across the 28 study lakes, mean THg concentrations of resident salmonid fishes varied as much as 18-fold among lakes. We used a hierarchal statistical approach to evaluate the relative importance of physiological, limnological, and catchment drivers of fish Hg concentrations. Our top statistical model explained 87% of the variability in fish THg concentrations among lakes with four key landscape and limnological variables: catchment conifer density (basal area of conifers within a lake's catchment), lake surface area, aqueous dissolved sulfate, and dissolved organic carbon. Conifer density within a lake's catchment was the most important variable explaining fish THg concentrations across lakes, with THg concentrations differing by more than 400 percent across the forest density spectrum. These results illustrate the importance of landscape characteristics in controlling mercury bioaccumulation in fish. Published by Elsevier

  6. A stationary phase solution for mountain waves with application to mesospheric mountain waves generated by Auckland Island

    NASA Astrophysics Data System (ADS)

    Broutman, Dave; Eckermann, Stephen D.; Knight, Harold; Ma, Jun

    2017-01-01

    A relatively general stationary phase solution is derived for mountain waves from localized topography. It applies to hydrostatic, nonhydrostatic, or anelastic dispersion relations, to arbitrary localized topography, and to arbitrary smooth vertically varying background temperature and vector wind profiles. A simple method is introduced to compute the ray Jacobian that quantifies the effects of horizontal geometrical spreading in the stationary phase solution. The stationary phase solution is applied to mesospheric mountain waves generated by Auckland Island during the Deep Propagating Gravity Wave Experiment. The results are compared to a Fourier solution. The emphasis is on interpretations involving horizontal geometrical spreading. The results show larger horizontal geometrical spreading for nonhydrostatic waves than for hydrostatic waves in the region directly above the island; the dominant effect of horizontal geometrical spreading in the lower ˜30 km of the atmosphere, compared to the effects of refraction and background density variation; and the enhanced geometrical spreading due to directional wind in the approach to a critical layer in the mesosphere.

  7. Lake Tengiz from space

    NASA Image and Video Library

    2017-12-08

    In orbit above the semi-desert grasslands in Kazakhstan, an astronaut aboard the International Space Station spotted one of the few features that stand out. Lake Tengiz is the only large lake (1590 square kilometers, 615 square miles) in northern Kazakhstan. Through white wisps of cloud, the crew member photographed the 50 kilometer-long eastern shore of the lake, with its thin, winding islands and white beaches. The islands and intervening waterways make a rich habitat for birds in this part of Asia. At least 318 species of birds have been identified at the lake; 22 of them are endangered. It is the northernmost habitat of the pink flamingo. The lake system is Kazakhstan’s first UNESCO World Heritage Site, and it has been declared a RAMSAR wetland site of international importance. Part of the richness of area is its complex hydrology. Fresh water enters the system via the Kulanutpes River, so there are small lakes (lower right) full of fresh water. But in this closed basin, the water in the main lake (top) slowly evaporates, becoming salty. Winds stir up bigger waves on the main lake, dispersing sediment and salt and making the water a cloudier and lighter blue-green. (Another astronaut photograph shows the entire lake system, while this story provides more information.) The strange shape of the islands is not easy to interpret. They may be drowned remnants of delta distributaries of the Kulanutpes River. Westerly winds probably have had a smoothing effect on the shorelines, especially in a shallow lake like Tengiz, which is only about 6 meters (20 feet) deep. The lake has an exciting history for people who follow space exploration. In 1976, a Soyuz spacecraft landed in the lake near the north shore (top right). The capsule crashed through the ice and sank during an October snowstorm when temperatures were -22°C (-8°F). Because of low power, the capsule was unheated and the crew was feared lost. It was many hours before the airtight capsule was located and

  8. Lake water quality mapping from Landsat

    NASA Technical Reports Server (NTRS)

    Scherz, J. P.

    1977-01-01

    In the project described remote sensing was used to check the quality of lake waters. The lakes of three Landsat scenes were mapped with the Bendix MDAS multispectral analysis system. From the MDAS color coded maps, the lake with the worst algae problem was easily located. The lake was closely checked, and the presence of 100 cows in the springs which fed the lake could be identified as the pollution source. The laboratory and field work involved in the lake classification project is described.

  9. Exploring talk about sexuality and living gay social lives among Chinese and South Asian gay and bisexual men in Auckland, New Zealand.

    PubMed

    Adams, Jeffery; Neville, Stephen

    2018-02-15

    To identify ways Chinese and South Asian gay and bisexual men living in Auckland talk about issues related to sexuality and experiences of living 'gay social lives.' Results will be available to inform health policy and practice. A qualitative design with individual interviews and thematic analysis was used. Semi-structured digitally recorded interviews were undertaken with 27 Chinese and 17 South Asian gay and bisexual men living in Auckland. Four themes in the data related to talk about sexuality and living gay social lives are reported: (a) 'Happy in my skin': Being gay is Ok! (b) 'To come out or not': Managing sexual identity, (c) 'Places to go, people to see': Connecting with others, and (d) 'What's wrong with being Asian': Tolerating discrimination. There are many similarities in the ways these men talked about their identity and sexuality that can be usefully considered by health policy makers and service planners. The concept of gay (and bisexual) sexuality had some salience for the men interviewed, despite the adoption and acknowledgement of same-sex identity being a relatively new phenomenon in some Asian countries. This supports the use of these terms in local health interventions. However, as these men closely managed their gay identity and typically had not disclosed their sexuality to others, including healthcare professionals, interventions to address the skills and comfort of healthcare providers in addressing sexuality in clinical settings appear warranted to facilitate optimal healthcare. These men are not well connected with others and this has implications for HIV health promotion that is based on creating cultural norms among networks to encourage safe sex. Discrimination results in many Chinese and South Asian gay and bisexual men disengaging from connecting with others and should be addressed.

  10. Increasing Incidence and Age at Diagnosis among Children with Type 1 Diabetes Mellitus over a 20-Year Period in Auckland (New Zealand)

    PubMed Central

    Derraik, José G. B.; Reed, Peter W.; Jefferies, Craig; Cutfield, Samuel W.; Hofman, Paul L.; Cutfield, Wayne S.

    2012-01-01

    Background We aimed to evaluate the incidence of type 1 diabetes mellitus in children <15 years of age (yr) in the Auckland region (New Zealand) over 20 years (1990–2009). Methods We performed a retrospective review of all patients <15 yr diagnosed with type 1 diabetes, from an unselected complete regional cohort. Results There were 884 new cases of type 1 diabetes, and age at diagnosis rose from 7.6 yr in 1990/1 to 8.9 yr in 2008/9 (r2 = 0.31, p = 0.009). There was a progressive increase in type 1 diabetes incidence among children <15 yr (p<0.0001), reaching 22.5 per 100,000 in 2009. However, the rise in incidence did not occur evenly among age groups, being 2.5-fold higher in older children (10–14 yr) than in the youngest group (0–4 yr). The incidence of new cases of type 1 diabetes was highest in New Zealand Europeans throughout the study period in all age groups (p<0.0001), but the rate of increase was similar in New Zealand Europeans and Non-Europeans. Type 1 diabetes incidence and average annual increase were similar in both sexes. There was no change in BMI SDS shortly after diagnosis, and no association between BMI SDS and age at diagnosis. Conclusions There has been a steady increase in type 1 diabetes incidence among children <15 yr in Auckland over 20 years. Contrary to other studies, age at diagnosis has increased and the greatest rise in incidence occurred in children 10–14 yr. There was little change in BMI SDS in this population, providing no support for the ‘accelerator hypothesis’. PMID:22389717

  11. Assessment of the Great Lakes Marine Renewable Energy Resources: Characterizing Lake Erie Surge, Seiche and Waves

    NASA Astrophysics Data System (ADS)

    Farhadzadeh, A.; Hashemi, M. R.

    2016-02-01

    Lake Erie, the fourth largest in surface area, smallest in volume and shallowest among the Great Lakes is approximately 400 km long and 90 km wide. Short term lake level variations are due to storm surge generated by high winds and moving pressure systems over the lake mainly in the southwest-northeast direction, along the lakes longitudinal axis. The historical wave data from three active offshore buoys shows that significant wave height can exceed 5 m in the eastern and central basins. The long-term lake level data show that storm surge can reach up to 3 m in eastern Lake Erie. Owing its shallow depth, Lake Erie frequently experiences seiching motions, the low frequency oscillations that are initiated by storm surge. The seiches whose first mode of oscillations has a period of nearly 14.2 hours can last from several hours to days. In this study, the Lake Erie potential for power generation, primarily using storm surge and seiche and also waves are assessed. Given the cyclic lake level variations due to storm-induced seiching, a concept similar to that of tidal range development is utilized to assess the potential of storm surge and seiche energy harvesting mechanisms for power generation. In addition, wave energy resources of the Lake is characterized -. To achieve these objectives, the following steps are taken : (1) Frequency of occurrence for extreme storm surge and wave events is determined using extreme value analysis such as Peak-Over-Threshold method for the long-term water level and wave data; (2) Spatial and temporal variations of wave height, storm surge and seiche are characterized. The characterization is carried out using the wave and storm surge outputs from numerical simulation of a number of historical extreme events. The coupled ADCIRC and SWAN model is utilized for the modeling; (3) Assessment of the potentials for marine renewable power generation in Lake Erie is made. The approach can be extended to the other lakes in the Great Lakes region.

  12. Combining lake and watershed characteristics with Landsat TM data for remote estimation of regional lake clarity

    USGS Publications Warehouse

    McCullough, Ian M.; Loftin, Cyndy; Sader, Steven A.

    2012-01-01

    Water clarity is a reliable indicator of lake productivity and an ideal metric of regional water quality. Clarity is an indicator of other water quality variables including chlorophyll-a, total phosphorus and trophic status; however, unlike these metrics, clarity can be accurately and efficiently estimated remotely on a regional scale. Remote sensing is useful in regions containing a large number of lakes that are cost prohibitive to monitor regularly using traditional field methods. Field-assessed lakes generally are easily accessible and may represent a spatially irregular, non-random sample of a region. We developed a remote monitoring program for Maine lakes >8 ha (1511 lakes) to supplement existing field monitoring programs. We combined Landsat 5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+) brightness values for TM bands 1 (blue) and 3 (red) to estimate water clarity (secchi disk depth) during 1990–2010. Although similar procedures have been applied to Minnesota and Wisconsin lakes, neither state incorporates physical lake variables or watershed characteristics that potentially affect clarity into their models. Average lake depth consistently improved model fitness, and the proportion of wetland area in lake watersheds also explained variability in clarity in some cases. Nine regression models predicted water clarity (R2 = 0.69–0.90) during 1990–2010, with separate models for eastern (TM path 11; four models) and western Maine (TM path 12; five models that captured differences in topography and landscape disturbance. Average absolute difference between model-estimated and observed secchi depth ranged 0.65–1.03 m. Eutrophic and mesotrophic lakes consistently were estimated more accurately than oligotrophic lakes. Our results show that TM bands 1 and 3 can be used to estimate regional lake water clarity outside the Great Lakes Region and that the accuracy of estimates is improved with additional model variables that reflect

  13. Survey of maternal sleep practices in late pregnancy in a multi-ethnic sample in South Auckland, New Zealand.

    PubMed

    Cronin, Robin S; Chelimo, Carol; Mitchell, Edwin A; Okesene-Gafa, Kara; Thompson, John M D; Taylor, Rennae S; Hutchison, B Lynne; McCowan, Lesley M E

    2017-06-17

    The Auckland Stillbirth study demonstrated a two-fold increased risk of late stillbirth for women who did not go to sleep on their left side. Two further studies have confirmed an increased risk of late stillbirth with supine sleep position. As sleep position is modifiable, we surveyed self-reported late pregnancy sleep position, knowledge about sleep position, and views about changing going-to-sleep position. Participants in this 2014 survey were pregnant women (n = 377) in their third trimester from South Auckland, New Zealand, a multi-ethnic and predominantly low socio-economic population. An ethnically-representative sample was obtained using random sampling. Multivariable logistic regression was performed to identify factors independently associated with non-left sided going-to-sleep position in late pregnancy. Respondents were 28 to 42 weeks' gestation. Reported going-to-sleep position in the last week was left side (30%), right side (22%), supine (3%), either side (39%) and other (6%). Two thirds (68%) reported they had received advice about sleep position. Non-left sleepers were asked if they would be able to change to their left side if it was better for their baby; 87% reported they would have little or no difficulty changing. Women who reported a non-left going-to-sleep position were more likely to be of Maori (aOR 2.64 95% CI 1.23-5.66) or Pacific (aOR 2.91 95% CI 1.46-5.78) ethnicity; had a lower body mass index (BMI) (aOR 0.93 95% CI 0.89-0.96); and were less likely to sleep on the left-hand side of the bed (aOR 3.29 95% CI 2.03-5.32). Maternal going-to-sleep position in the last week was side-lying in 91% of participants. The majority had received advice to sleep on their side or avoid supine sleep position. Sleeping on the left-hand side of the bed was associated with going-to-sleep on the left side. Most non-left sleepers reported their sleeping position could be modified to the left side suggesting a public health intervention about sleep

  14. Assessing reactivation of the Pourewa Landslide Zone, Auckland, New Zealand, using Structure-from-Motion, LiDAR, and geophysics

    NASA Astrophysics Data System (ADS)

    Brook, Martin; Liu, Shanshan; Richards, Nick; Bevan, David; Prebble, Warwick

    2017-04-01

    Landslides pose significant risks to communities and infrastructure particularly in urban areas, and mitigating these risks relies on understanding landslide triggering processes that may cause reactivation. Previous work has shown that landslides are often complex, multiphase processes where gradual deterioration of shear strength within the subsurface precedes slope failure and the appearance of surface morphological features. Here, we combine a suite of remote sensing and direct invasive testing techniques to assess reactivation of the Pourewa Landslide Zone (PLZ), located in Auckland, New Zealand. The PLZ is located on the inner wall of the north-eastern flank of the Orakei volcano, 4 km east of Auckland CBD. The landslide zone occupies slopes above the east bank of the tidal Pourewa Creek, which lies within a residential area. Four landslides are located within the PLZ (from west to east): Ngapipi Road Landslide, Kepa Road Landslide, St Josephs Landslide, and Pourewa Landslide. Inward collapse of the crater walls since the initial eruption (>85 ka) has enlarged the crater to c. 1000 m diameter, with some slopes prone to ongoing mass movements. Indeed, reactivation during the 20th century led to the realignment of Kepa Road, and surface cracking of roads in the vicinity is ongoing. LiDAR imagery was used to develop high resolution geomorphological maps, and this data was compared with more recent Structure-from-Motion (SfM) photogrammetry, obtained from an unmanned aerial vehicle (UAV). The digital surface models and derived cross-sections developed from these data allow both the initial failure, and subsequent reactivations to be assessed in detail. Geophysical surveys included Electromagnetic Induction (EMI), augmented by information relating to lithological, moisture and strength variation with depth, allowing initial interpretation of zones likely to be prone to reactivation. Ongoing slope deformation includes shallow, retrogressive failure on the upper

  15. Biotic and abiotic factors related to lake herring recruitment in the Wisconsin waters of Lake Superior, 1984-1998

    USGS Publications Warehouse

    Hoff, Michael H.

    2004-01-01

    Lake Superior lake herring (Coregonus artedi) recruitment to 13-14 months of age in the Wisconsin waters of Lake Superior varied by a factor of 5,233 during 1984-1998. Management agencies have sought models that accurately predict recruitment, but no satisfactory model had previously been developed. Lake herring recruitment was modeled to determine which factors most explained recruitment variability. The Ricker stock-recruitment model derived from only the paired stock and recruit data explained 35% of the variability in the recruitment data. The functional relationship that explained the greatest amount of recruitment variation (93%) included lake herring stock size, lake trout (Salvelinus namaycush) population size, slimy sculpin (Cottus cognatus) biomass, the interaction of mean daily wind speed in April (month of hatch) and lake herring stock size, and mean air temperature in April (when lake herring are 12-months old). Model results were interpreted to mean that lake herring recruitment was affected negatively by: slimy sculpin predation on lake herring ova; predation on age-0 lake herring by lake trout; and adult cannibalism on lake herring larvae, which was reduced by increased wind speed. April temperature was the variable that explained the least amount of variability in recruitment, but lake herring recruitment was positively affected by a warm April, which shortened winter and apparently reduced first-winter mortality. Stock size caused compensatory, density-dependent mortality on lake herring recruits. Management efforts appear best targeted at stock size protection, and empirical data implies that stock size in the Wisconsin waters of the lake should be maintained at 2.1-15.0 adults/ha in spring, bottom-trawl surveys.

  16. Ecology under lake ice.

    PubMed

    Hampton, Stephanie E; Galloway, Aaron W E; Powers, Stephen M; Ozersky, Ted; Woo, Kara H; Batt, Ryan D; Labou, Stephanie G; O'Reilly, Catherine M; Sharma, Sapna; Lottig, Noah R; Stanley, Emily H; North, Rebecca L; Stockwell, Jason D; Adrian, Rita; Weyhenmeyer, Gesa A; Arvola, Lauri; Baulch, Helen M; Bertani, Isabella; Bowman, Larry L; Carey, Cayelan C; Catalan, Jordi; Colom-Montero, William; Domine, Leah M; Felip, Marisol; Granados, Ignacio; Gries, Corinna; Grossart, Hans-Peter; Haberman, Juta; Haldna, Marina; Hayden, Brian; Higgins, Scott N; Jolley, Jeff C; Kahilainen, Kimmo K; Kaup, Enn; Kehoe, Michael J; MacIntyre, Sally; Mackay, Anson W; Mariash, Heather L; McKay, Robert M; Nixdorf, Brigitte; Nõges, Peeter; Nõges, Tiina; Palmer, Michelle; Pierson, Don C; Post, David M; Pruett, Matthew J; Rautio, Milla; Read, Jordan S; Roberts, Sarah L; Rücker, Jacqueline; Sadro, Steven; Silow, Eugene A; Smith, Derek E; Sterner, Robert W; Swann, George E A; Timofeyev, Maxim A; Toro, Manuel; Twiss, Michael R; Vogt, Richard J; Watson, Susan B; Whiteford, Erika J; Xenopoulos, Marguerite A

    2017-01-01

    Winter conditions are rapidly changing in temperate ecosystems, particularly for those that experience periods of snow and ice cover. Relatively little is known of winter ecology in these systems, due to a historical research focus on summer 'growing seasons'. We executed the first global quantitative synthesis on under-ice lake ecology, including 36 abiotic and biotic variables from 42 research groups and 101 lakes, examining seasonal differences and connections as well as how seasonal differences vary with geophysical factors. Plankton were more abundant under ice than expected; mean winter values were 43.2% of summer values for chlorophyll a, 15.8% of summer phytoplankton biovolume and 25.3% of summer zooplankton density. Dissolved nitrogen concentrations were typically higher during winter, and these differences were exaggerated in smaller lakes. Lake size also influenced winter-summer patterns for dissolved organic carbon (DOC), with higher winter DOC in smaller lakes. At coarse levels of taxonomic aggregation, phytoplankton and zooplankton community composition showed few systematic differences between seasons, although literature suggests that seasonal differences are frequently lake-specific, species-specific, or occur at the level of functional group. Within the subset of lakes that had longer time series, winter influenced the subsequent summer for some nutrient variables and zooplankton biomass. © 2016 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

  17. Methane distribution and transportation in Lake Chaohu: a shallow eutrophic lake in Eastern China

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Shen, Q.

    2016-12-01

    Global warming and eutrophication are two world widely concerned environmental problems. Methane is the second important greenhouse gas, and lake has been proven as a quite important natural source of methane emission. More methane may emit from eutrophic lake due to the higher organic matter deposition in the lake sediment. Lake Chaohu is a large and shallow eutrophic lake in eastern China (N31°25' 31°43', E117°16' 117°05'), with an area of 770 km2 and a mean depth of 2.7 m. To examine methane distribution and transportation in this eutrophic lake, field study across different seasons was carried out with 20 study sites in the lake. Samples from the different water and sediment depth was collected using headspace bottle, and methane content was measured by gas chromatography using a flame ionization detector. The potential methane production in the sediment was examined by an indoor incubation experiment. Methane flux from sediment to the overlying water was calculated by Fick's law, and methane emission from surface to the air was calculated at the same time. The results indicates that more methane accumulated in the water of northwestern bay in this lake, and higher methane release rates was also found at this area. Methane increases gradually with depth in the top 10 cm in sediment cores, then it almost keeps at constant state in the deeper sediment. In the sediment from northwestern bay, more methane content and the higher potential methane production was found compared to the sediment from the east area of this lake.

  18. Treating floodplain lakes of large rivers as study units for variables that vary within lakes; an evaluation using chlorophyll a and inorganic suspended solids data from floodplain lakes of the Upper Mississippi River

    USGS Publications Warehouse

    Gray, B.R.; Rogala, J.R.; Houser, J.N.

    2013-01-01

    Contiguous floodplain lakes ('lakes') have historically been used as study units for comparative studies of limnological variables that vary within lakes. The hierarchical nature of these studies implies that study variables may be correlated within lakes and that covariate associations may differ not only among lakes but also by spatial scale. We evaluated the utility of treating lakes as study units for limnological variables that vary within lakes based on the criteria of important levels of among-lake variation in study variables and the observation of covariate associations that vary among lakes. These concerns were selected, respectively, to ensure that lake signatures were distinguishable from within-lake variation and that lake-scale effects on covariate associations might provide inferences not available by ignoring those effects. Study data represented chlorophyll a (CHL) and inorganic suspended solids (ISS) data from lakes within three reaches of the Upper Mississippi River. Sampling occurred in summer from 1993 through 2005 (except 2003); numbers of lakes per reach varied from 7 to 19, and median lake area varied from 53 to 101 ha. CHL and ISS levels were modelled linearly, with lake, year and lake x year effects treated as random. For all reaches, the proportions of variation in CHL and ISS attributable to differences among lakes (including lake and lake x year effects) were substantial (range: 18%-73%). Finally, among-lake variation in CHL and ISS was strongly associated with covariates and covariate effects that varied by lakes or lake-years (including with vegetation levels and, for CHL, log(ISS)). These findings demonstrate the utility of treating floodplain lakes as study units for the study of limnological variables and the importance of addressing hierarchy within study designs when making inferences from data collected within floodplain lakes.

  19. Preferred temperatures of juvenile lake whitefish

    USGS Publications Warehouse

    Edsall, Thomas A.

    1999-01-01

    Lake whitefish (Coregonus clupeaformis) supported valuable commercial fisheries in all of the Great Lakes until the 1950s to 1960s when their populations collapsed due to overfishing, pollution, and predation by the exotic sea lamprey (Petromyzon marinus). Reduction of these population stresses has permitted significant recovery of the lake whitefish in the upper three Great Lakes since the 1980s, and limited but encouraging recovery is now apparent in Lakes Erie and Ontario. In the present study the thermal preferences of age-0 and age-1 lake whitefish were measured in the laboratory to provide a basis for determining thermal habitat use by juvenile lake whitefish and thermal niche overlap with exotic fishes that might prey on them. Final thermal preferenda of young lake whitefish varied inversely with fish size ranging from 16.8°C for fish averaging 1.9 g to 15.6°C for age-1 fish averaging 3.9 g. Final thermal preferenda were in agreement with the limited published information on temperature selection of juvenile lake whitefish in the laboratory and on thermal habitat use by wild, free-ranging populations in the Great Lakes.

  20. Estimating the volume of Alpine glacial lakes

    NASA Astrophysics Data System (ADS)

    Cook, S. J.; Quincey, D. J.

    2015-09-01

    Supraglacial, moraine-dammed and ice-dammed lakes represent a potential glacial lake outburst flood (GLOF) threat to downstream communities in many mountain regions. This has motivated the development of empirical relationships to predict lake volume given a measurement of lake surface area obtained from satellite imagery. Such relationships are based on the notion that lake depth, area and volume scale predictably. We critically evaluate the performance of these existing empirical relationships by examining a global database of measured glacial lake depths, areas and volumes. Results show that lake area and depth are not always well correlated (r2 = 0.38), and that although lake volume and area are well correlated (r2 = 0.91), there are distinct outliers in the dataset. These outliers represent situations where it may not be appropriate to apply existing empirical relationships to predict lake volume, and include growing supraglacial lakes, glaciers that recede into basins with complex overdeepened morphologies or that have been deepened by intense erosion, and lakes formed where glaciers advance across and block a main trunk valley. We use the compiled dataset to develop a conceptual model of how the volumes of supraglacial ponds and lakes, moraine-dammed lakes and ice-dammed lakes should be expected to evolve with increasing area. Although a large amount of bathymetric data exist for moraine-dammed and ice-dammed lakes, we suggest that further measurements of growing supraglacial ponds and lakes are needed to better understand their development.

  1. Benthic-planktonic coupling, regime shifts, and whole-lake primary production in shallow lakes.

    PubMed

    Genkai-Kato, Motomi; Vadeboncoeur, Yvonne; Liboriussen, Lone; Jeppesen, Erik

    2012-03-01

    Alternative stable states in shallow lakes are typically characterized by submerged macrophyte (clear-water state) or phytoplankton (turbid state) dominance. However, a clear-water state may occur in eutrophic lakes even when macrophytes are absent. To test whether sediment algae could cause a regime shift in the absence of macrophytes, we developed a model of benthic (periphyton) and planktonic (phytoplankton) primary production using parameters derived from a shallow macrophyte-free lake that shifted from a turbid to a clear-water state following fish removal (biomanipulation). The model includes a negative feedback effect of periphyton on phosphorus (P) release from sediments. This in turn induces a positive feedback between phytoplankton production and P release. Scenarios incorporating a gradient of external P loading rates revealed that (1) periphyton and phytoplankton both contributed substantially to whole-lake production over a broad range of external P loading in a clear-water state; (2) during the clear-water state, the loss of benthic production was gradually replaced by phytoplankton production, leaving whole-lake production largely unchanged; (3) the responses of lakes to biomanipulation and increased external P loading were both dependent on lake morphometry; and (4) the capacity of periphyton to buffer the effects of increased external P loading and maintain a clear-water state was highly sensitive to relationships between light availability at the sediment surface and the of P release. Our model suggests a mechanism for the persistence of alternative states in shallow macrophyte-free lakes and demonstrates that regime shifts may trigger profound changes in ecosystem structure and function.

  2. Population dynamics of Lake Ontario lake trout during 1985-2007

    USGS Publications Warehouse

    Brenden, Travis O.; Bence, James R.; Lantry, Brian F.; Lantry, Jana R.; Schaner, Ted

    2011-01-01

    Lake trout Salvelinus namaycush were extirpated from Lake Ontario circa 1950 owing to commercial and recreational fishing, predation by sea lampreys Petromyzon marinus, and habitat degradation. Since the 1970s, substantial efforts have been devoted to reestablishing a self-sustaining population through stocking, sea lamprey control, and harvest reduction. Although a stocking-supported population has been established, only limited natural reproduction has been detected. Since the 1990s, surveys have indicated a continuing decline in overall abundance despite fairly static stocking levels. We constructed a statistical catch-at-age model to describe the dynamics of Lake Ontario lake trout from 1985 to 2007 and explore what factor(s) could be causing the declines in abundance. Model estimates indicated that abundance had declined by approximately 76% since 1985. The factor that appeared most responsible for this was an increase in age-1 natural mortality rates from approximately 0.9 to 2.5 between 1985 and 2002. The largest source of mortality for age-2 and older fish was sea lamprey predation, followed by natural and recreational fishing mortality. Exploitation was low, harvest levels being uncertain and categorized by length rather than age. Accurate predictions of fishery harvest and survey catch per unit effort were obtained despite low harvest levels by using atypical data (e.g., numbers stocked as an absolute measure of recruitment) and a flexible modeling approach. Flexible approaches such as this might allow similar assessments for a wide range of lightly exploited stocks. The mechanisms responsible for declining age-1 lake trout survival are unknown, but the declines were coincident with an increase in the proportion of stocked fish that were of the Seneca strain and a decrease in the overall stocking rate. It is possible that earlier studies suggesting that Seneca strain lake trout would be successful in Lake Ontario are no longer applicable given the large

  3. The Great Lakes

    EPA Pesticide Factsheets

    The Great Lakes form the largest surface freshwater system on Earth. The U.S. and Canada work together to restore and protect the environment in the Great Lakes Basin. Top issues include contaminated sediments, water quality and invasive species.

  4. Changes in depth occupied by Great Lakes lake whitefish populations and the influence of survey design

    USGS Publications Warehouse

    Rennie, Michael D.; Weidel, Brian C.; Claramunt, Randall M.; Dunlob, Erin S.

    2015-01-01

    Understanding fish habitat use is important in determining conditions that ultimately affect fish energetics, growth and reproduction. Great Lakes lake whitefish (Coregonus clupeaformis) have demonstrated dramatic changes in growth and life history traits since the appearance of dreissenid mussels in the Great Lakes, but the role of habitat occupancy in driving these changes is poorly understood. To better understand temporal changes in lake whitefish depth of capture (Dw), we compiled a database of fishery-independent surveys representing multiple populations across all five Laurentian Great Lakes. By demonstrating the importance of survey design in estimating Dw, we describe a novel method for detecting survey-based bias in Dw and removing potentially biased data. Using unbiased Dw estimates, we show clear differences in the pattern and timing of changes in lake whitefish Dw between our reference sites (Lake Superior) and those that have experienced significant benthic food web changes (lakes Michigan, Huron, Erie and Ontario). Lake whitefish Dw in Lake Superior tended to gradually shift to shallower waters, but changed rapidly in other locations coincident with dreissenid establishment and declines in Diporeia densities. Almost all lake whitefish populations that were exposed to dreissenids demonstrated deeper Dw following benthic food web change, though a subset of these populations subsequently shifted to more shallow depths. In some cases in lakes Huron and Ontario, shifts towards more shallow Dw are occurring well after documented Diporeia collapse, suggesting the role of other drivers such as habitat availability or reliance on alternative prey sources.

  5. Changes in consumption by alewives and lake whitefish after dreissenid mussel invasions in Lakes Michigan and Huron

    USGS Publications Warehouse

    Pothoven, S.A.; Madenjian, C.P.

    2008-01-01

    Growth of alewives Alosa pseudoharengus and lake whitefish Coregonus clupeaformis has declined since the arrival and spread of dreissenid mussels in Lakes Michigan and Huron. Alewives are the main forage for the salmonids in Lake Michigan, and lake whitefish are the most important commercial species in both lakes. Bioenergetics modeling was used to determine consumption by the average individual fish before and after the dreissenid invasion and to provide insight into the invasion's effects on fish growth and food web dynamics. Alewives feed on both Zooplankton and benthic macroinvertebrates, and lake whitefish are benthivores. Annual consumption of zooplankton by an average alewife in Lake Michigan was 37% lower and consumption of benthic macroinvertebrates (amphipods Diporeia spp., opossum shrimp Mysis relicta, and Chironomidae) was 19% lower during the postinvasion period (1995-2005) than during the preinvasion period (1983-1994). Reduced consumption by alewives corresponded with reduced alewife growth. In Lakes Michigan and Huron, consumption of nonmollusk macroinvertebrates (Diporeia spp., opossum shrimp, Chironomidae) by the average lake whitefish was 46-96% lower and consumption of mollusks (mainly dreissenids and gastropods) was 2-5 times greater during the postinvasion period than during the preinvasion period. Even though total food consumption by lake whitefish did not differ between the two periods in Lake Huron or the Southern Management Unit in Lake Michigan, postinvasion weight at age was at least 38% lower than preinvasion weight at age. Under the current postinvasion diet regime, consumption by lake whitefish would have to increase by up to 122% to achieve preinvasion growth rates. ?? Copyright by the American Fisheries Society 2008.

  6. WINCHESTER LAKE, LEWIS COUNTY, IDAHO - CLEAN LAKES PHASE II IMPLEMENTATION AND RESTORATION PROJECT, 1996

    EPA Science Inventory

    Winchester Lake, Idaho (17060306) is an 85 acre recreation site located approximately 30 miles southeast of Lewiston. The lake has been involved in the U.S. EPA Clean Lakes Program since 1988. The Phase I Diagnostic and Feasibility Study, completed in February 1990, identified t...

  7. Historical changes to Lake Washington and route of the Lake Washington Ship Canal, King County, Washington

    USGS Publications Warehouse

    Chrzastowski, Michael J.

    1983-01-01

    Lake Washington, in the midst of the greater Seattle metropolitan area of the Puget Sound region (fig. 1), is an exceptional commercial, recreational, and esthetic resource for the region . In the past 130 years, Lake Washington has been changed from a " wild " lake in a wilderness setting to a regulated lake surrounded by a growing metropolis--a transformation that provides an unusual opportunity to study changes to a lake's shoreline and hydrologic characteristics -resulting from urbanization.

  8. Residues of DDT in lake trout (Salvelinus namaycush) and coho salmon (Oncorhynchus kisutch) from the Great Lakes

    USGS Publications Warehouse

    Reinert, Robert E.; Bergman, Harold L.

    1974-01-01

    Concentrations of DDT residues were higher in lake trout (Salvelinus namaycush) from southern Lake Michigan in 1966–70 (average 18.1 ppm in fish 558–684 mm long) than in lake trout of the same size-class from Lake Superior in 1968–69 (4.4 ppm), and higher in adult coho salmon (Oncorhynchus kisutch) from Lake Michigan in 1968–71 (averages for different year-classes, 9.9–14.0 ppm) than in those from Lake Erie in 1969 (2.2 ppm). Residues were significantly higher in lake trout from southern Lake Michigan than in those from the northern part of the lake. In lakes Michigan and Superior, the levels increased with length of fish and percentage oil. In Lake Michigan coho salmon, the residues remained nearly stable (2–4 ppm) from September of the 1st yr of lake residence through May or early June of the 2nd yr, but increased three to four times in the next 3 mo. Residues in Lake Erie coho salmon did not increase during this period, which preceded the spawning season. Although the concentrations of total residues in whole, maturing Lake Michigan coho salmon remained unchanged from August 1968 until near the end of the spawning season in January 1969, the residues were redistributed in the tissues of the spawning-run fish; concentrations in the loin and brain were markedly higher in January than in August. This relocation of DDT residues accompanied a marked decrease in the percentage of oil in the fish, from 13.2 in August to 2.8 in January. Concentrations of residues were relatively high in eggs of both lake trout (4.6 ppm) and coho salmon (7.4–10.2 ppm) from Lake Michigan. The percentage composition of the residues (p,p′DDE, o,p′/DDT, p,p′DDT, and p,p′DDT) did not differ significantly with life stage, size, age, or locality, or date of collection of lake trout or coho salmon.

  9. Survival of hatchery-reared lake trout stocked near shore and off shore in Lake Ontario

    USGS Publications Warehouse

    Elrod, Joseph H.

    1997-01-01

    Establishing a stock of mature, hatchery-reared fish is necessary to restore a self-sustaining population of lake trout Salvelinus namaycush in Lake Ontario. Stocking fish off shore rather than near shore to reduce predation on these fish by large lake trout or piscivorous birds may enhance survival of hatchery-reared fish and accelerate establishment of a population of adults. Results of an earlier study did not support routinely stocking fish off shore by helicopter in Lake Ontario, but stresses associated with helicopter stocking suggested another method of transporting fish off shore might enhance survival. I conducted this study to determine whether stocking lake trout off shore by barge would enhance first-year survival. Two lots of yearling lake trout were stocked at each of four locations in Lake Ontario in May 1992. One lot was stocked from shore, and an identical lot was transported by barge 3.4–10.4 km off shore of nearshore locations and stocked in water 46–52 m deep. Fish were recovered during trawl, gillnet, and creel surveys in 1992–1996. First-year survival of lake trout stocked off shore tended to be better than that of fish stocked near shore. Predation by double-crested cormorantsPhalacrocorax auritus likely affected survival of fish stocked near shore at two locations, 7 and 37 km, respectively, from a nesting colony of 5,443 pairs of double-crested cormorants. Predation by large lake trout remains a viable hypothesis, which explains, at least partially, lower survival of lake trout stocked near shore at two other locations. Stocking lake trout off shore of traditional nearshore stocking sites likely will enhance first-year survival of hatchery-reared fish and promote accumulation of an adult population, especially for those occassions where nearshore stocking locations are near nesting colonies of double-crested cormorants.

  10. Climate of a high altitude lake basin and lake-atmosphere interactions - observations and atmospheric modelling

    NASA Astrophysics Data System (ADS)

    Maussion, F.; Kropacek, J.; Finkelnburg, R.; Scherer, D.

    2012-04-01

    Large lakes and inland water bodies have a significant influence on their local climate. The hydrometeorological effect of inland water bodies is varying greatly between seasons, years and contrasting climatic conditions. It is generally hypothesised that the cool air above the lake will inhibit convection in summer; conversely, the relatively warm lake in late-autumn will initiate convective instability that may generate strong snowfalls. In this study we focus on the lake Nam Co (2'000 sq.km, 4700 m a.s.l). Located in a transition zone between the continental climate of Central Asia and the Indian Monsoon system, the Nam Co lake is covered by ice from mid-January to end of April and reaches surface temperatures of 13 °C in summer. We address three main research questions: (i) what is the influence of the Nam Co lake on local meteorological variables over the course of the year, (ii) what is the impact of the timing of the lake freezing on late-autumn and winter precipitation fields and (iii) how will the influence of the lake evolve in the context of a changing climate? In order to answer these questions, we combine satellite observations of lake surface temperatures from the ARC-Lake product and atmospheric modelling using the WRF model. The spatio-temporal variability of temperature, wind and precipitation fields during the last decade are analyzed using high-resolution (up to 2 km) simulations. The positive impact of the assimilation of the lake surface temperatures for the initialization of the model is analysed and discussed, as well as the combined influences of the large scale (westerlies, monsoon) and local (orographic) forcings. Our results are of relevance for any regional climate or hydrological modelling study and bring new insights in our understanding of the complex hydrometeorological processes taking place on the Tibetan Plateau.

  11. Glacier, Glacial Lake, and Ecological Response Dynamics of the Imja Glacier-Lake-Moraine System, Nepal

    NASA Astrophysics Data System (ADS)

    Kargel, J. S.; Shugar, D. H.; Leonard, G. J.; Haritashya, U. K.; Harrison, S.; Shrestha, A. B.; Mool, P. K.; Karki, A.; Regmi, D.

    2016-12-01

    Glacier response dynamics—involving a host of processes—produce a sequence of short- to long-term delayed responses to any step-wise, oscillating, or continuous trending climatic perturbation. We present analysis of Imja Lake, Nepal and examine its thinning and retreat and a sequence of the detachment of tributaries; the inception and growth of Imja Lake and concomitant glacier retreat, thinning, and stagnation, and relationships to lake dynamics; the response dynamics of the ice-cored moraine; the development of the local ecosystem; prediction of short-term dynamical responses to lake lowering (glacier lake outburst flood—GLOF—mitigation); and prospects for coming decades. The evolution of this glacier system provides a case study by which the global record of GLOFs can be assessed in terms of climate change attribution. We define three response times: glacier dynamical response time (for glacier retreat, thinning, and slowing of ice flow), limnological response time (lake growth), and GLOF trigger time (for a variety of hazardous trigger events). Lake lowering (to be completed in August 2016; see AGU abstract by D. Regmi et al.) will reduce hazards, but we expect that the elongation of the lake and retreat of the glacier will continue for decades after a pause in 2016-2017. The narrowing of the moraine dam due to thaw degradation of the ice-cored end moraine means that the hazard due to Imja Lake will soon again increase. We examine both long-term response dynamics, and two aspects of Himalayan glaciers that have very rapid responses: the area of Imja Lake fluctuates seasonally and even with subseasonal weather variations in response to changes in lake temperature and glacier meltback; and as known from other studies, glacier flow speed can vary between years and even on shorter timescales. The long-term development and stabilization of glacial moraines and small lacustrine plains in drained lake basins impacts the development of local ecosystems

  12. First report and characterization of adult Uncinaria spp. in New Zealand Sea Lion (Phocarctos hookeri) pups from the Auckland Islands, New Zealand.

    PubMed

    Castinel, A; Duignan, P J; Pomroy, W E; Lyons, E T; Nadler, S A; Dailey, M D; Wilkinson, I S; Chilvers, B L

    2006-03-01

    Two species of hookworms (Uncinaria lucasi and Uncinaria hamiltoni) have been formally described from pinnipeds, but dissimilar types are noted from these hosts. This report is the first description of hookworms (Uncinaria spp.) from the New Zealand sea lion, Phocarctos hookeri. The nematodes were collected from dead pups on Enderby Island (Auckland Islands, 50 degrees 30', 166 degrees 17') during January and February, 2004. Standard measurements of male and female hookworms were obtained, providing a general morphometric characterization of the hookworm species in P. hookeri. Considerable variations in the body length of adult hookworms were noted within the same host. The arrangement of some of the bursal rays differs from that described for U. lucasi and U. hamiltoni.

  13. Characteristics of nurses providing diabetes community and outpatient care in Auckland.

    PubMed

    Daly, Barbara; Arroll, Bruce; Sheridan, Nicolette; Kenealy, Timothy; Scragg, Robert

    2013-03-01

    There is a worldwide trend for diabetes care to be undertaken in primary care. Nurses are expected to take a leading role in diabetes management, but their roles in primary care are unclear in New Zealand, as are the systems of care they work in as well as their training. To describe and compare demographic details, education and diabetes experience, practice setting and facilities available for the three main groups of primary health care nurses working in the largest urban area in New Zealand. Of the total number of practice nurses, district nurses and specialist nurses working in Auckland (n=1091), 31% were randomly selected to undertake a self-administered questionnaire and telephone interview in 2006-2008. Overall response was 86% (n=284 self-administered questionnaires, n=287 telephone interviews). Almost half (43%) of primary care nurses were aged over 50 years. A greater proportion of specialist nurses (89%) and practice nurses (84%) had post-registration diabetes education compared with district nurses (65%, p=0.005), from a range of educational settings including workshops, workplaces, conferences and tertiary institutions. More district nurses (35%) and practice nurses (32%) had worked in their current workplace for >10 years compared with specialist nurses (14%, p=0.004). Over 20% of practice nurses and district nurses lacked access to the internet, and the latter group had the least administrative facilities and felt least valued. These findings highlight an ageing primary health care nursing workforce, lack of a national primary health care post-registration qualification and a lack of internet access.

  14. Great Lakes, No Clouds

    NASA Image and Video Library

    2017-12-08

    NASA image acquired August 28, 2010 Late August 2010 provided a rare satellite view of a cloudless summer day over the entire Great Lakes region. North Americans trying to sneak in a Labor Day weekend getaway on the lakes were hoping for more of the same. The Great Lakes comprise the largest collective body of fresh water on the planet, containing roughly 18 percent of Earth's supply. Only the polar ice caps contain more fresh water. The region around the Great Lakes basin is home to more than 10 percent of the population of the United States and 25 percent of the population of Canada. Many of those people have tried to escape record heat this summer by visiting the lakes. What they found, according to The Hamilton Spectator, was record-breaking water temperatures fueled by record-breaking air temperatures in the spring and summer. By mid-August, the waters of Lake Superior were 6 to 8°C (11 to 14°F) above normal. Lake Michigan set records at about 4°C (7°F) above normal. The other three Great Lakes – Huron, Erie, and Ontario -- were above normal temperatures, though no records were set. The image was gathered by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite at 1:30 p.m. Central Daylight Time (18:30 UTC) on August 28. Open water appears blue or nearly black. The pale blue and green swirls near the coasts are likely caused by algae or phytoplankton blooms, or by calcium carbonate (chalk) from the lake floor. The sweltering summer temperatures have produced an unprecedented bloom of toxic blue-green algae in western Lake Erie, according to the Cleveland Plain Dealer. NASA image by Jeff Schmaltz, MODIS Rapid Response Team, Goddard Space Flight Center. Caption by Mike Carlowicz. Instrument: Aqua - MODIS Click here to see more images from NASA Goddard’s Earth Observatory NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft

  15. Expanding models of lake trophic state to predict cyanobacteria in lakes

    EPA Science Inventory

    Background/Question/Methods: Cyanobacteria are a primary taxonomic group associated with harmful algal blooms in lakes. Understanding the drivers of cyanobacteria presence has important implications for lake management and for the protection of human and ecosystem health. Chlor...

  16. Causes of declining survival of lake trout stocked in U.S. waters of Lake Superior in 1963-1986

    USGS Publications Warehouse

    Hansen, Michael J.; Ebener, Mark P.; Schorfhaar, Richard G.; Schram, Stephen T.; Schreiner, Donald R.; Selgeby, James H.; Taylor, William W.

    1996-01-01

    Survival of the 1963-1982 year-classes of stocked yearling lake trout Salvelinus namaycush declined significantly over time in Lake Superior. To investigate possible causes of this decline, a Ricker model of stock-recruitment was used to describe the catch per effort (CPE) of age-7 stocked lake trout in the Michigan, Minnesota, and Wisconsin waters of Lake Superior as functions of the numbers of yearlings stocked 6 years earlier (an index of density dependence), the density (CPE) of wild adult lake trout (an index of predation), and large-mesh (a?Y 114-mm stretch-measure) gill-net fishing effort (an index of fishing mortality). Declining CPE of stocked lake trout in Michigan and Wisconsin was significantly associated with increasing large-mesh gillnet fishing effort. Declining CPE of stocked lake trout in Minnesota was significantly associated with increasing density of wild lake trout. Declining survival of stocked lake trout may therefore have been caused by increased mortality in large-mesh gill-net fisheries in Michigan and Wisconsin, and by predation by wild lake trout that recently recolonized the Minnesota area. We recommend that experimental management be pursued to determine the relative importance of large-mesh gillnet fishing effort and of predation by wild lake trout on the survival of stocked lake trout in U.S. waters of Lake Superior.

  17. Seasonal food of juvenile lake trout in U.S. waters of Lake Ontario

    USGS Publications Warehouse

    Elrod, Joseph H.

    1983-01-01

    Stomach contents of 3,554 lake trout (Salvelinus namaycush), 100 to 449 mm in total length, captured with bottom trawls during April through October 1978–81 along the south shore of Lake Ontario were examined. Invertebrates appeared to be an important food of lake trout less than 200 mm long but were only occasionally eaten by larger fish. For all seasons and size groups of juvenile lake trout combined, the slimy sculpin (Cottus cognatus) was the principal forage fish, making up 42% (by weight) of identifiable fish remains. Young-of-the-year slimy sculpins were a major food of recently stocked yearling lake trout during July through October. Alewives (Alosa pseudoharengus) were the principal forage during April and May, and made up 28% (by weight) of the identifiable fish remains. They were rarely eaten during July and August, however, when lake trout remained in the hypolimnion and alewives were above it. Over 99% of the alewives eaten from April through August were yearlings and over 99% eaten during October were young-of-the-year. Rainbow smelt (Osmerus mordax) were the primary forage during July and August, but contributed only a small part of the diet during other seasons; overall, they made up 25% of identifiable fish remains. Johnny darters (Etheostoma nigrum) made up 4% of identifiable fish remains and were most common in stomachs of small lake trout during October.

  18. Suppression of invasive lake trout in an isolated backcountry lake in Glacier National Park

    USGS Publications Warehouse

    Fredenberg, C. R.; Muhlfeld, Clint C.; Guy, Christopher S.; D'Angelo, Vincent S.; Downs, Christopher C.; Syslo, John M.

    2017-01-01

    Fisheries managers have implemented suppression programmes to control non-native lake trout, Salvelinus namaycush (Walbaum), in several lakes throughout the western United States. This study determined the feasibility of experimentally suppressing lake trout using gillnets in an isolated backcountry lake in Glacier National Park, Montana, USA, for the conservation of threatened bull trout, Salvelinus confluentus (Suckley). The demographics of the lake trout population during suppression (2009–2013) were described, and those data were used to assess the effects of suppression scenarios on population growth rate (λ) using an age-structured population model. Model simulations indicated that the population was growing exponentially (λ = 1.23, 95% CI: 1.16–1.28) prior to suppression. However, suppression resulted in declining λ(0.61–0.79) for lake trout, which was concomitant with stable bull trout adult abundances. Continued suppression at or above observed exploitation levels is needed to ensure continued population declines.

  19. Lake Chad, Chad, Africa

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Hydrologic and ecologic changes in the Lake Chad Basin are shown in this Oct 1992 photograph. In space photo documentation, Lake Chad was at its greatest area extent (25,000 sq. km.) during Gemini 9 in June 1966 (see S66-38444). Its reduction during the severe droughts from 1968 to 1974 was first noted during Skylab (1973-1974). After the drought began again in 1982, the lake reached its minimum extent (1,450 sq. km.) in Space Shuttle photographs taken in 1984 and 1985. In this STS-52 photograph, Lake Chad has begun to recover. The area of the open water and interdunal impoundments in the southern basin (the Chari River Basin) is estimated to be 1,900 to 2100 sq. km. Note the green vegetation in the valley of the K'Yobe flow has wetted the northern lake basin for the first time in several years. There is evidence of biomass burning south of the K'Yobe Delta and in the vegetated interdunal areas near the dike in the center of the lake. Also note the dark 'Green Line' of the Sahel (the g

  20. 78 FR 11094 - Safety Zone; Lake Worth Dredge Operations, Lake Worth Inlet; West Palm Beach, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-15

    ... 1625-AA00 Safety Zone; Lake Worth Dredge Operations, Lake Worth Inlet; West Palm Beach, FL AGENCY... safety zone on Lake Worth Inlet, West Palm Beach, Florida, to provide for the safety of life and vessels..., dredging operations will be conducted on Lake Worth Inlet in West Palm Beach, Florida. These operations...

  1. Ohio Lake Erie Commission Homepage

    Science.gov Websites

    view the Lake Erie Protection & Restoration Plan 2016. Phosphorus Task Force Click here to see the Ohio Lake Erie Phosphorus Task Force II Final Report 2013. About the Lake Erie Commission The role of

  2. Early Holocene Great Salt Lake

    USGS Publications Warehouse

    Oviatt, Charles G.; Madsen, David B.; Miller, David; Thompson, Robert S.; McGeehin, John P.

    2015-01-01

    Shorelines and surficial deposits (including buried forest-floor mats and organic-rich wetland sediments) show that Great Salt Lake did not rise higher than modern lake levels during the earliest Holocene (11.5–10.2 cal ka BP; 10–9 14C ka BP). During that period, finely laminated, organic-rich muds (sapropel) containing brine-shrimp cysts and pellets and interbedded sodium-sulfate salts were deposited on the lake floor. Sapropel deposition was probably caused by stratification of the water column — a freshwater cap possibly was formed by groundwater, which had been stored in upland aquifers during the immediately preceding late-Pleistocene deep-lake cycle (Lake Bonneville), and was actively discharging on the basin floor. A climate characterized by low precipitation and runoff, combined with local areas of groundwater discharge in piedmont settings, could explain the apparent conflict between evidence for a shallow lake (a dry climate) and previously published interpretations for a moist climate in the Great Salt Lake basin of the eastern Great Basin.

  3. Estimating the volume of Alpine glacial lakes

    NASA Astrophysics Data System (ADS)

    Cook, S. J.; Quincey, D. J.

    2015-12-01

    Supraglacial, moraine-dammed and ice-dammed lakes represent a potential glacial lake outburst flood (GLOF) threat to downstream communities in many mountain regions. This has motivated the development of empirical relationships to predict lake volume given a measurement of lake surface area obtained from satellite imagery. Such relationships are based on the notion that lake depth, area and volume scale predictably. We critically evaluate the performance of these existing empirical relationships by examining a global database of glacial lake depths, areas and volumes. Results show that lake area and depth are not always well correlated (r2 = 0.38) and that although lake volume and area are well correlated (r2 = 0.91), and indeed are auto-correlated, there are distinct outliers in the data set. These outliers represent situations where it may not be appropriate to apply existing empirical relationships to predict lake volume and include growing supraglacial lakes, glaciers that recede into basins with complex overdeepened morphologies or that have been deepened by intense erosion and lakes formed where glaciers advance across and block a main trunk valley. We use the compiled data set to develop a conceptual model of how the volumes of supraglacial ponds and lakes, moraine-dammed lakes and ice-dammed lakes should be expected to evolve with increasing area. Although a large amount of bathymetric data exist for moraine-dammed and ice-dammed lakes, we suggest that further measurements of growing supraglacial ponds and lakes are needed to better understand their development.

  4. Hydrology of Central Florida Lakes - A Primer

    USGS Publications Warehouse

    Schiffer, Donna M.

    1998-01-01

    INTRODUCTION Lakes are among the most valued natural resources of central Florida. The landscape of central Florida is riddled with lakeswhen viewed from the air, it almost seems there is more water than land. Florida has more naturally formed lakes than other southeastern States, where many lakes are created by building dams across streams. The abundance of lakes on the Florida peninsula is a result of the geology and geologic history of the State. An estimated 7,800 lakes in Florida are greater than 1 acre in surface area. Of these, 35 percent are located in just four counties (fig. 1): Lake, Orange, Osceola, and Polk (Hughes, 1974b). Lakes add to the aesthetic and commercial value of the area and are used by many residents and visitors for fishing, boating, swimming, and other types of outdoor recreation. Lakes also are used for other purposes such as irrigation, flood control, water supply, and navigation. Residents and visitors commonly ask questions such as Whyare there so many lakes here?, Why is my lake drying up (or flooding)?, or Is my lake spring-fed? These questions indicate that the basic hydrology of lakes and the interaction of lakes with ground water and surface water are not well understood by the general population. Because of the importance of lakes to residents of central Florida and the many questions and misconceptions about lakes, this primer was prepared by the U.S. Geological Survey (USGS) in cooperation with the St. Johns River Water Management District and the South Florida Water Management District. The USGS has been collecting hydrologic data in central Florida since the 1920s, obtaining valuable information that has been used to better understand the hydrology of the water resources of central Florida, including lakes. In addition to data collection, as of 1994, the USGS had published 66 reports and maps on central Florida lakes (Garcia and Hoy, 1995). The main purpose of this primer is to describe the hydrology of lakes in central

  5. Limnology of selected lakes in Ohio, 1975

    USGS Publications Warehouse

    Tobin, Robert L.; Youger, John D.

    1977-01-01

    Water-quality reconnaissance by the U.S. Geological Survey and Ohio Environmental Protection Agency, to evaluate the status of Ohio's lakes and reservoirs was begun in 1975 with studies of 17 lakes. Spring and summer data collections for each lake included: profile measurements of temperature, dissolved oxygen, pH, and specific conductance; field and laboratory analyses of physical, biological, chemical organic characteristics; (nutrient), and concentrations of major and minor chemical constituents from composites of the water column; and physical and chemical data from major inflows.Light penetration (secchi disk) ranged from 9.4 feet (2.9 meters) in Lake Hope to 0.4 feet (0.1 meter) in Acton Lake. Seasonal thermal stratification or stability is shown for 10 lakes deeper than 15 feet (4.6 meters). Unstable or modified temperature profiles were observed in shallow lakes (depths less than 15 feet) or lakes controlled through subsurface release valves.Dissolved oxygen saturation ranged from 229 percent (20.8 milligrams per liter) in the epilimnion of Paint Creek Lake to zero in the bottom waters of all thermally stabilized lakes. Marked chemical and physical differences and nutrient uptake and recycling developed within different thermal strata. Anaerobic zones were frequently characterized by hydrogen sulfide and ammonia.Calcium was the dominant or codominant cation, and bicarbonate and(or) sulfate were the major anions in all lakes sampled. Only Hope and Vesuvius Lakes had soft water (hardness less than 61 milligrams per liter as CaCO3 ), and both lakes were further characterized by low pH (less than 7.0). Specific conductance ranged from 510 micromhos (Deer Creek and Salt Fork Lakes) to 128 micromhos (Lake Hope). Pesticide residues were detected in Acton Lake, and concentrations of one or more trace metals were at or above Ohio Environmental Protection Agency recommended limits in 11 lakes.Fecal coliform colony counts were below 400 colonies per 100 milliliters in

  6. 33 CFR 162.136 - Connecting waters from Lake Huron to Lake Erie; anchorage grounds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... to Lake Erie; anchorage grounds. 162.136 Section 162.136 Navigation and Navigable Waters COAST GUARD... REGULATIONS § 162.136 Connecting waters from Lake Huron to Lake Erie; anchorage grounds. (a) In the Detroit...: There is an authorized anchorage in Canadian waters just above Fighting Island and an authorized...

  7. 33 CFR 162.136 - Connecting waters from Lake Huron to Lake Erie; anchorage grounds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... to Lake Erie; anchorage grounds. 162.136 Section 162.136 Navigation and Navigable Waters COAST GUARD... REGULATIONS § 162.136 Connecting waters from Lake Huron to Lake Erie; anchorage grounds. (a) In the Detroit...: There is an authorized anchorage in Canadian waters just above Fighting Island and an authorized...

  8. 33 CFR 162.136 - Connecting waters from Lake Huron to Lake Erie; anchorage grounds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... to Lake Erie; anchorage grounds. 162.136 Section 162.136 Navigation and Navigable Waters COAST GUARD... REGULATIONS § 162.136 Connecting waters from Lake Huron to Lake Erie; anchorage grounds. (a) In the Detroit...: There is an authorized anchorage in Canadian waters just above Fighting Island and an authorized...

  9. 33 CFR 162.136 - Connecting waters from Lake Huron to Lake Erie; anchorage grounds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to Lake Erie; anchorage grounds. 162.136 Section 162.136 Navigation and Navigable Waters COAST GUARD... REGULATIONS § 162.136 Connecting waters from Lake Huron to Lake Erie; anchorage grounds. (a) In the Detroit...: There is an authorized anchorage in Canadian waters just above Fighting Island and an authorized...

  10. An innovative community organizing campaign to improve mental health and wellbeing among Pacific Island youth in South Auckland, New Zealand.

    PubMed

    Han, Hahrie; Nicholas, Alexandra; Aimer, Margaret; Gray, Jonathon

    2015-12-01

    To examine whether being an organizer in a community organizing program improves personal agency and self-reported mental health outcomes among low-income Pacific Island youth in Auckland, New Zealand. Counties Manukau Health initiated a community organizing campaign led and run by Pacific Island youth. We used interviews, focus groups and pre- and post-campaign surveys to examine changes among 30 youths as a result of the campaign. Ten youths completed both pre- and post-campaign surveys. Eleven youths participated in focus groups, and four in interviews. Overall, youths reported an increased sense of agency and improvements to their mental health. Community organizing has potential as a preventive approach to improving mental health and developing agency over health among disempowered populations. © The Royal Australian and New Zealand College of Psychiatrists 2015.

  11. Lake water quality mapping from LANDSAT

    NASA Technical Reports Server (NTRS)

    Scherz, J. P.

    1977-01-01

    The lakes in three LANDSAT scenes were mapped by the Bendix MDAS multispectral analysis system. Field checking the maps by three separate individuals revealed approximately 90-95% correct classification for the lake categories selected. Variations between observers was about 5%. From the MDAS color coded maps the lake with the worst algae problem was easily located. This lake was closely checked and a pollution source of 100 cows was found in the springs which fed this lake. The theory, lab work and field work which made it possible for this demonstration project to be a practical lake classification procedure are presented.

  12. Persistent Ice on Lake Superior

    NASA Image and Video Library

    2017-12-08

    Though North America is a full month into astronomical spring, the Great Lakes have been slow to give up on winter. As of April 22, 2014, the Great Lakes were 33.9 percent ice covered. The lake they call Superior dominated the pack. In the early afternoon on April 20, 2014, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this natural-color image of Lake Superior, which straddles the United States–Canada border. At the time Aqua passed over, the lake was 63.5 percent ice covered, according to the NOAA Great Lakes Environmental Research Lab (GLERL). Averaged across Lake Superior, ice was 22.6 centimeters (8.9 inches) thick; it was as much as twice that thickness in some locations. GLERL researcher George Leshkevich affirmed that ice cover this spring is significantly above normal. For comparison, Lake Superior had 3.6 percent ice cover on April 20, 2013; in 2012, ice was completely gone by April 12. In the last winter that ice cover grew so thick on Lake Superior (2009), it reached 93.7 percent on March 2 but was down to 6.7 percent by April 21. Average water temperatures on all of the Great Lakes have been rising over the past 30 to 40 years and ice cover has generally been shrinking. (Lake Superior ice was down about 79 percent since the 1970s.) But chilled by persistent polar air masses throughout the 2013-14 winter, ice cover reached 88.4 percent on February 13 and 92.2 percent on March 6, 2014, the second highest level in four decades of record-keeping. Air temperatures in the Great Lakes region were well below normal for March, and the cool pattern is being reinforced along the coasts because the water is absorbing less sunlight and warming less than in typical spring conditions. The graph below, based on data from Environment Canada, shows the 2014 conditions for all of the Great Lakes in mid-April compared to the past 33 years. Lake Superior ice cover got as high as 95.3 percent on March 19. By April 22, it was

  13. Influence of permafrost on lake terraces of Lake Heihai (NE Tibetan Plateau)

    NASA Astrophysics Data System (ADS)

    Lockot, Gregori; Hartmann, Kai; Wünnemann, Bernd

    2013-04-01

    The Tibetan Plateau (TP) is one of the key regions for climatic global change. Besides the poles the TP is the third highest storage of frozen water in glaciers. Here global warming is three times higher than in the rest of the world. Additionally the TP provides water for billions of people and influences the moisture availability from the Indian and East Asian monsoon systems. During the Holocene extent and intensity of the monsoonal systems changed. Hence, in the last decades, a lot of work was done to reconstruct timing and frequency of monsoonal moisture, to understand the past and give a better forecast for the future. Comparative workings often show very heterogeneous patterns of timing and frequency of the Holocene precipitation and temperature maximum, emphasizing the local importance of catchment dynamics. In this study we present first results of lake Heihai (36°N, 93°15'E, 4500m a.s.l.), situated at the north-eastern border of the TP. The lake is surrounded by a broad band of near-shore lake sediments, attesting a larger lake extent in the past. These sediments were uplifted by permafrost, reaching nowadays heights ca. +8 meters above present lake level. Due to the uplift one of the main inflows was blocked and the whole hydrology of the catchment changed. To quantify the uplift of permafrost Hot Spot Analysis were accomplished at a DEM of the near-shore area. As a result regions of high permafrost uplift and those which mirror the original height of lake ground were revealed. The most obvious uplift took place in the northern and western part of the lake, where the four uplift centers are located. In contrast the southern and eastern areas show a rather degraded pattern (probably by fluvial erosion, thermokarst, etc.). The ancient lake bottom, without permafrost uplift was estimated to be 4-6 meters above the modern lake level. For a better understanding of permafrost interaction inside the terrace bodies a 5m sediment profile was sampled and

  14. Discrimination among spawning aggregations of lake herring from Lake Superior using whole-body morphometric characters

    USGS Publications Warehouse

    Hoff, Michael H.

    2004-01-01

    The lake herring (Coregonus artedi) was one of the most commercially and ecologically valuable Lake Superior fishes, but declined in the second half of the 20th century as the result of overharvest of putatively discrete stocks. No tools were previously available that described lake herring stock structure and accurately classified lake herring to their spawning stocks. The accuracy of discriminating among spawning aggregations was evaluated using whole-body morphometrics based on a truss network. Lake herring were collected from 11 spawning aggregations in Lake Superior and two inland Wisconsin lakes to evaluate morphometrics as a stock discrimination tool. Discriminant function analysis correctly classified 53% of all fish from all spawning aggregations, and fish from all but one aggregation were classified at greater rates than were possible by chance. Discriminant analysis also correctly classified 66% of fish to nearest neighbor groups, which were groups that accounted for the possibility of mixing among the aggregations. Stepwise discriminant analysis showed that posterior body length and depth measurements were among the best discriminators of spawning aggregations. These findings support other evidence that discrete stocks of lake herring exist in Lake Superior, and fishery managers should consider all but one of the spawning aggregations as discrete stocks. Abundance, annual harvest, total annual mortality rate, and exploitation data should be collected from each stock, and surplus production of each stock should be estimated. Prudent management of stock surplus production and exploitation rates will aid in restoration of stocks and will prevent a repeat of the stock collapses that occurred in the middle of the 20th century, when the species was nearly extirpated from the lake.

  15. REDUCING EXPOSURE UNCERTAINTY FOR ASSESSMENT OF DIOXIN TOXICITY RISKS TO LAKE TROUT POPULATIONS IN THE GREAT LAKES

    EPA Science Inventory

    During the 20th century, declines of lake trout (Salvelinus namaycush) populations to virtual extinction in all the Great Lakes except Lake Superior were followed by failure of stocked lake trout to achieve recruitment through natural reproduction. Stresses such as excessive harv...

  16. Whiting in Lake Michigan

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Satellites provide a view from space of changes on the Earth's surface. This series of images from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) aboard the Orbview-2 satellite shows the dramatic change in the color of Lake Michigan during the summer. The bright color that appears in late summer is probably caused by calcium carbonate-chalk-in the water. Lake Michigan always has a lot of calcium carbonate in it because the floor of the lake is limestone. During most of the year the calcium carbonate remains dissolved in the cold water, but at the end of summer the lake warms up, lowering the solubility of calcium carbonate. As a result, the calcium carbonate precipitates out of the water, forming clouds of very small solid particles that appear as bright swirls from above. The phenomenon is appropriately called a whiting event. A similar event occured in 1999, but appears to have started later and subsided earlier. It is also possible that a bloom of the algae Microcystis is responsible for the color change, but unlikely because of Lake Michigan's depth and size. Microcystis blooms have occured in other lakes in the region, however. On the shore of the lake it is possible to see the cities of Chicago, Illinois, and Milwaukee, Wisconsin. Both appear as clusters of gray-brown pixels. Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  17. Rapid increase of lakes in Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Ren, H.; Fan, W.; Yao, Y., Sr.; Tian, D.; MA, B.; LIU, R.; Qin, Q.

    2016-12-01

    The Tibetan Plateau, covered with a huge area of snow, glaciers and lakes, feeds several large rivers, incluidng Yangtze River, Yellow River, Yarlung Tsangpo River and Lancang River. Climate change can cause lakes to expand and bring floods and mudflows, and the response of lakes in this plateau to global climate change is very crucial. Using time-series Landsats clear-sky images in summer from the late 1980s to 2015, we established a new finer-resolution (30m) database of lakes in the plateau among five stages (1980s, 1995, 2000, 2005 and 2015), analyzed lake changes in the past three decades, and explored the possible driving forces. Results and discussions(1) Changes in lakes > 1km2 between 1980s and 2015The changes of lake numbers and surface areas were investigated between 1980s and 2015. The lakes were identified by visual interpretation and classified to several different sizes: small (1-10km2), medium (10-50km2), large (50-100km2) and huge (>100km2) lakes. A total of 1375 lakes (>1km2) were detected in 2015, in which the small, medium, large and huge lakes respectively account for 97, 74, 262 and 942 (Fig.1 and Table 1). The numbers of lakes (> 1km2 ) has increased by 384 from 991 in 1980s (Fig.2 a, b). Meanwhile, a rapid increase of lake surface area also occurred: increased by 28.2% from 37711.0km2 in 1980s to 48335.2km2 in 2015 (Fig.2c and Table 1). (2) Temporal changes in lakes > 10km2 between 1980s and 2015Temporal variation in all lakes > 10km2 were investigated at the five stages. Most lakes have expanded (Fig.3). The water surface area of large and huge lakes increased by 13.7% from a total area of 32056.7km2 in 1980s to 36437.0km2 in 2015. For example, Siling Co, which is the largest lake in Tibet region and second largest lake in Tibetan Plateau, has increased by 702.1 km2 (41.0%) to 2416.08 km2 since 1980s with an rate about 28 km2 /a. Some new lakes or water bodies appeared due to melting glaciers or anthropogenic intervention. A few of small

  18. Large rock-slope failures impacting on lakes - Reconstruction of events and deciphering mobility processes at Lake Oeschinen (CH) and Lake Eibsee (D)

    NASA Astrophysics Data System (ADS)

    Knapp, Sibylle; Anselmetti, Flavio; Gilli, Adrian; Krautblatter, Michael; Hajdas, Irka

    2017-04-01

    Among single event landslide disasters large rock-slope failures account for 75% of disasters with more than 1000 casualties. The precise determination of recurrence rates and failure volumes combined with an improved understanding of mobility processes are essential to better constrain runout models and establish early warning systems. Here we present the data sets from the two alpine regions Lake Oeschinen (CH) and Lake Eibsee (D) to show how lake studies can help to decipher the multistage character of rock-slope failures and to improve the understanding of the processes related to rock avalanche runout dynamics. We focus on such that impacted on a (paleo-) lake for two main reasons. First, the lake background sedimentation acts as a natural chronometer, which enables the stratigraphic positioning of events and helps to reconstruct the event history. This way it becomes possible to (i) decipher the multistage character of the failure of a certain rock slope and maybe detect progressive failure, (ii) determine the recurrence rates of failures at that certain rock slope, and (iii) consider energies based on estimated failure volumes, fall heights and deposition patterns. Hence, the interactions between a rock-slope failure, the water reservoir and the altered rock-slope are better understood. Second, picturing a rock avalanche running through and beyond a lake, we assume the entrainment of water and slurry to be crucial for the subsequent flow dynamics. The entrainment consumes a large share of the total energy, and orchestrates the mobility leading to fluidization, a much higher flow velocity and a longer runout-path length than expected. At Lake Oeschinen (CH) we used lake sediment cores and reflection seismic profiles in order to reconstruct the 2.5 kyrs spanning rock-slope failure history including 10 events, six of which detached from the same mountain flank, and correlated them with (pre-) historical data. The Lake Eibsee records provide insights into the

  19. Walleye in Lake Erie and Lake St. Clair

    USGS Publications Warehouse

    Nepszy, S.J.; Davies, D.H.; Einhouse, D.; Hatch, R.W.; Isbell, G.; MacLennan, D.; Muth, K.M.

    1991-01-01

    The history and current status of walleye (Stizostedion vitreum vitreum) stocks in Lake Erie and Lake St. Clair are reviewed in relation to their exploitation by commercial and recreational fishermen, environmental factors, rehabilitation efforts, and community dynamics. Management initiatives and stock recovery under these processes are outlined. After the collapse of the fishery in 1957, the highly productive walleye stock of western Lake Erie remained depressed through the 1960s, while the eastern basin stock remained stable. Closure of the fishery for walleye from 1970-73 because of mercury contamination provided an opportunity for the development of an international interagency management plan. With quota management, the walleye stock in western Lake Erie responded well to limited exploitation, steadily increased, and expanded its range. As population expanded, growth began to decline and was more apparent in the young-of-the-year (YOY) in the 1970s, and in older walleye in the late 1970s and 1980s. At the turn of the century, commercial harvest of walleye in Lake St. Clair ranged from 12-127 tonnes annually. A relatively stable period from 1910-59 was followed by significantly increased harvests (100-150 t) in 1959-65. This increase was a result of increased commercial exploitation as well as an increased abundance of walleye. After the mercury contamination problem of 1970, angling effort and harvest was reduced but then gradually increased in Ontario waters from 37 t in 1973 to 62 t in 1988. The increased mean age of the stock during the early 1970s was due to a few strong year-classes (1970, 1972, and 1974) as well as a period of stable or reduced catch per unit effort. With the current mean age not reduced significantly, the stocks of walleye should continue to provide good yields.

  20. Mariano Lake Mine

    EPA Pesticide Factsheets

    Mariano Lake Mine is located in the Mariano Lake Chapter of the Navajo Nation, approximately 25 miles east of Gallup, N.M in McKinley County. EPA is working with Navajo Nation Environmental Protection Agency (NNEPA) to oversee cleanup work by Chevron U.S.A