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Sample records for lakes fish consumption

  1. Great Lakes fish consumption and reproductive outcomes

    SciTech Connect

    Dar, E.

    1989-01-01

    This epidemiological investigation determined prenatal exposure to polychlorinated biphenyls (PCBs), through contaminated fish consumption, and ascertained reproductive outcomes. Green Bay, Wisconsin was chosen as the study site because it was known for its environmental contamination of PCBs. These chemicals are environmentally stable and persistent, and tend to bioaccumulate up the food chain, with highest levels found in predatory sport fish from Lake Michigan. The Green Bay area provided a population with potential PCB exposure from sport fish consumption. Accidental poisoning incidents showed detrimental reproductive effects of high dose PCB exposures. A Michigan study found significant effects on birth weight and gestational age when mothers consumed two sport fish meals per month. This study population was drawn from women during their first prenatal visit at two Green Bay clinics during a one year period. 1,112 participants completed a self-administered questionnaire. Maternal and cord blood samples were obtained for selected PCB serum analyses. Reproductive outcome measures were abstracted from hospital labor reports. Study results indicated that maternal consumption was correlated to maternal PCB serum levels. Regression techniques estimated significant exposure coefficients for subsets of two birth size parameters. Birth length was positively associated with PCB exposure in shorter mothers. Significant associations of PCB exposure and birth weight percentiles were estimated for two income groups in the urban residence/weight gain less than 34 pounds subset.

  2. Mercury concentrations in fish from Lake Meredith, Texas: implications for the issuance of fish consumption advisories.

    PubMed

    McClain, William C; Chumchal, Matthew M; Drenner, Ray W; Newland, Leo W

    2006-12-01

    We examined how length of fish is related to mercury concentrations in muscle tissue of seven species of fish from Lake Meredith, Texas and determined how sex and growth rate are related to mercury concentration in walleye (Sander vitreus). Flathead catfish (Pylodictis olivaris), walleye and white bass (Morone chrysops) had the highest concentrations of mercury and channel catfish (Ictalurus punctatus), common carp (Cyprinus carpio), river carpsucker (Carpiodes carpio) and gizzard shad (Dorosoma cepedianum) had the lowest concentrations of mercury. Mercury concentrations were positively correlated with total length (TL) of fish for all species except gizzard shad, which exhibited a negative correlation between mercury concentration and TL. Male walleye grew more slowly than females, and males had higher concentrations of mercury than females. We also assessed the differences in fish consumption advisories that would be issued using Texas Department of State Health Services (DSHS) guidelines versus United States Environmental Protection Agency (USEPA) recommendations. Using DSHS guidelines, no fish species in Lake Meredith would be issued a fish consumption advisory. Nevertheless, DSHS has issued an advisory for walleye in Lake Meredith, possibly due to an inadequate sample size of fish. Using USEPA guidelines, a fish consumption advisory would be issued for the largest size class of flathead catfish but no advisory exists for flathead catfish in Lake Meredith. We suggest that when fish in a lake may be contaminated with mercury, all game fish in the lake should be assessed, and mercury advisories should take fish size into account.

  3. PARENTAL CONSUMPTION OF CONTAMINATED SPORT FISH FROM LAKE ONTARIO AND PREDICTED FECUNDABILITY

    EPA Science Inventory

    Wildlife studies suggest that consumption of contaminated fish from the Great Lakes may expose humans to polychlorinated biphenyls and persistent chlorinated pesticides. To assess whether time to pregnancy or fecundability is affected, we conducted a telephone survey in 1993 with...

  4. Paternal Lake Ontario fish consumption and risk of conception delay, New York State Angler Cohort.

    PubMed

    Buck, G M; Mendola, P; Vena, J E; Sever, L E; Kostyniak, P; Greizerstein, H; Olson, J; Stephen, F D

    1999-02-01

    The aquatic ecosystems of the Great Lakes are contaminated with a variety of compounds, some of which are considered reproductive toxicants. Few studies of paternal fish consumption and reproductive endpoints have been undertaken and serve as the impetus for study. Standardized telephone interviews were conducted with 2445 female members of the New York State Angler Cohort (82% response) to update reproductive profiles and to ascertain specific information on time-to-pregnancy (TTP). The study sample includes women with a known TTP and paternal fish consumption data (n=785). Conception delay was defined as more than 12 cycles of unprotected intercourse to achieve pregnancy. Paternal fish consumption was assessed by three measures: frequency of Lake Ontario sport fish meals in 1991, numbers of years eating fish, and estimated PCB exposure from fish consumption. Adjusted ORs for number of fish meals, based on logistic regression, ranged from 0.69 to 0.80; from 0.61 to 0.82 for number of years eating fish; and from 0.44 to 1.14 for quartiles of estimated PCB exposure from fish consumption. All confidence intervals included one. These findings suggest that, based on paternal self-reports, Lake Ontario fish consumption does not increase the risk of conception delay.

  5. Paternal Lake Ontario fish consumption and risk of conception delay, New York state angler cohort

    SciTech Connect

    Buck, G.M.; Mendola, P.; Vena, J.E.; Kostyniak, P.; Greizerstein, H.; Olson, J.; Stephen, F.D.; Sever, L.E.

    1999-02-01

    The aquatic ecosystems of the Great Lakes are contaminated with a variety of compounds, some of which are considered reproductive toxicants. Few studies of paternal fish consumption and reproductive endpoints have been undertaken and serve as the impetus for study. Standardized telephone interviews were conducted with 2,445 female members of the New York State Angler Cohort (82% response) to update reproductive profiles and to ascertain specific information on time-to-pregnancy (TTP). The study sample includes women with a known TTP and paternal fish consumption data (n = 785). Conception delay was defined as more than 12 cycles of unprotected intercourse to achieve pregnancy. Paternal fish consumption was assessed by three measures: frequency of Lake Ontario sport fish meals in 1991, numbers of years eating fish, and estimated PCB exposure from fish consumption. Adjusted ORs for number of fish meals, based on logistic regression, ranged from 0.69 to 0.80; from 0.61 to .82 for number of years eating fish; and from 0.44 to 1.14 for quartiles of estimated PCB exposure from fish consumption. All confidence intervals included one. These findings suggest that, based on paternal self-reports, Lake Ontario fish consumption does not increase the risk of conception delay.

  6. Fish consumption among women anglers of childbearing age in the Great Lakes region.

    PubMed

    Connelly, Nancy A; Bruce Lauber, T; Niederdeppe, Jeff; Knuth, Barbara A

    2016-10-01

    Fish consumption advisories are issued by the federal government for women of childbearing age (WCBA). These advisories make recommendations about the amount and types of fish that should be consumed to provide the greatest health benefits to women and their children while avoiding risks from chemical contaminants. We used diary methods to study fish consumption patterns of 1395 WCBA in the Great Lakes coastal region who purchased fishing licenses, a group which has significant opportunity to eat larger quantities of fish. Very few members of this group reported exceeding the federal recommendations for total fish consumption (between 3% and 5% depending on assumptions about portion sizes), consumption of canned "white" tuna (0%), or consumption of "do not eat" species (4%). They did report eating more fish on average than recent national study estimates, but they did not report consuming as much fish as is recommended to obtain the greatest health benefits of fish consumption. Only 10-12% of study participants reported eating within the recommended range of 8-12oz. of fish per week, with 84-87% eating less than the recommended amount. Additional efforts are likely needed to encourage WCBA to eat more low-risk fish, even among this group of higher-than-average fish consumers.

  7. Urban anglers in the Great Lakes region: Fish consumption patterns, influences, and responses to advisory messages.

    PubMed

    Bruce Lauber, T; Connelly, Nancy A; Niederdeppe, Jeff; Knuth, Barbara A

    2017-07-15

    The U.S. Environmental Protection Agency and many state advisory programs consider urban anglers at high risk of being exposed to contaminants through fish consumption because the urban poor may be dependent on fish they catch for food and lack access to non-contaminated fishing sites. Past research has supported this characterization of urban anglers, but most studies have been site-specific and limited to subsets of urban anglers. We used a mail survey and focus groups to (a) explore how urban anglers living in the Great Lakes region of the United States differed from rural and suburban anglers and (b) characterize their fishing patterns, fish consumption, factors influencing their fish consumption, and response to fish consumption advisory messages. Although we detected some differences between licensed urban, suburban, and rural anglers, their magnitude was not striking. Lower income urban anglers tended to consume less purchased and sport-caught fish than higher income urban anglers and were not at high risk as a group. Nevertheless, focus group data suggested there may be subpopulations of urban anglers, particularly from immigrant populations, that consume higher amounts of potentially contaminated fish. Although urban anglers in general may not require a special approach for communicating fish consumption advice, subpopulations within this group may be best targeted by using community-based programs to communicate fish consumption advice.

  8. Effects of Great Lakes fish consumption on brain PCB pattern, concentration, and progressive-ratio performance

    SciTech Connect

    Stewart, P.; Pagano, J.; Sargent, D.; Darvill, T.; Lonky, E.; Reihman, J.

    2000-01-01

    This study investigated the effects of consumption of Great Lakes fish on progressive ratio performance, and on the pattern and concentrations of brain polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethene (DDE), and mirex in the rat. Adult, male Sprague-Dawley rats were fed a 30% diet of either Lake Ontario salmon (LAKE), Pacific Ocean salmon, or lab chow control for 20 or 65 days. Following the treatment regimen, half the rats from each group were sacrificed immediately for gas chromatographic analysis of organochlorine contaminants, and the other half were tested on a multiple fixed-ratio-progressive-ratio reinforcement schedule and then sacrificed for analysis. Consumption of Lake Ontario fish resulted in significantly higher levels of brain PCBs, DDE, and mirex relative to controls, but still well within human exposure ranges. Consumption of Lake Ontario fish for 20 or 65 days produced an average brain PCB concentration of 457 and 934 ng/g fat, respectively. Consumption of laboratory rat chow or Pacific Ocean salmon for 20 or 65 days produced an average brain PCB concentration of 240, 464, and 441 ng/g fat, respectively. Moreover, both LAKE-fed groups showed a much more heavily chlorinated pattern of brain PCBs than all control groups, as evidenced by both significant increases in the most heavily chlorinated PCB congeners and significant increases in the average chlorine biphenyl.

  9. Consumption dynamics of the adult piscivorous fish community in Spirit Lake, Iowa

    USGS Publications Warehouse

    Liao, H.; Pierce, C.L.; Larscheid, J.G.

    2004-01-01

    At Spirit Lake, one of Iowa's most important fisheries, walleye Sander vitreus (formerly Stizostedion vitreum) is one of the most popular species with anglers. Despite a century of walleye stocking and management in Spirit Lake, walleye growth rate, size structure, and angler harvest continue to decline. Our purpose was to determine the magnitude and dynamics of walleye population consumption relative to those of other piscivorous species in Spirit Lake, which would allow managers to judge the feasibility of increasing the abundance, growth rate, and size structure of the walleye population. We quantified food consumption by the adult piscivorous fish community in Spirit Lake over a 3-year period. Data on population dynamics, diet, energy density, and water temperature from 1995 to 1997 were used in bioenergetics models to estimate total consumption by walleye, yellow perch Perca flavescens, smallmouth bass Micropterus dolomieu, largemouth bass Micropterus salmoides, black crappie Pomoxis nigromaculatus, and northern pike Esox lucius. Estimated annual consumption by the piscivorous community varied roughly fourfold, ranging from 154,752 kg in 1995 to 662,776 kg in 1997. Walleyes dominated total consumption, accounting for 68, 73, and 90% (1995-1997, respectively) of total food consumption. Walleyes were also the dominant consumers of fish, accounting for 76, 86, and 97% of piscivorous consumption; yellow perch followed, accounting for 16% of piscivorous consumption in 1995 and 12% in 1996. Yellow perch were the predominant fish prey species in all 3 years, accounting for 68, 52, and 36% of the total prey consumed. Natural reproduction is weak, so high walleye densities are maintained by intensive stocking. Walleye stocking drives piscivorous consumption in Spirit Lake, and yearly variation in the cannibalism of stocked walleye fry may be an important determinant of walleye year-class strength and angler success. Reducing walleye stocking intensity, varying stocking

  10. Planktivory in the changing Lake Huron zooplankton community: Bythotrephes consumption exceeds that of Mysis and fish

    USGS Publications Warehouse

    Bunnell, D.B.; Davis, B.M.; Warner, D.M.; Chriscinske, M.A.; Roseman, E.F.

    2011-01-01

    Oligotrophic lakes are generally dominated by calanoid copepods because of their competitive advantage over cladocerans at low prey densities. Planktivory also can alter zooplankton community structure. We sought to understand the role of planktivory in driving recent changes to the zooplankton community of Lake Huron, a large oligotrophic lake on the border of Canada and the United States. We tested the hypothesis that excessive predation by fish (rainbow smelt Osmerus mordax, bloater Coregonus hoyi) and invertebrates (Mysis relicta, Bythotrephes longimanus) had driven observed declines in cladoceran and cyclopoid copepod biomass between 2002 and 2007. We used a field sampling and bioenergetics modelling approach to generate estimates of daily consumption by planktivores at two 91-m depth sites in northern Lake Huron, U.S.A., for each month, May-October 2007. Daily consumption was compared to daily zooplankton production. Bythotrephes was the dominant planktivore and estimated to have eaten 78% of all zooplankton consumed. Bythotrephes consumption exceeded total zooplankton production between July and October. Mysis consumed 19% of all the zooplankton consumed and exceeded zooplankton production in October. Consumption by fish was relatively unimportant - eating only 3% of all zooplankton consumed. Because Bythotrephes was so important, we explored other consumption estimation methods that predict lower Bythotrephes consumption. Under this scenario, Mysis was the most important planktivore, and Bythotrephes consumption exceeded zooplankton production only in August. Our results provide no support for the hypothesis that excessive fish consumption directly contributed to the decline of cladocerans and cyclopoid copepods in Lake Huron. Rather, they highlight the importance of invertebrate planktivores in structuring zooplankton communities, especially for those foods webs that have both Bythotrephes and Mysis. Together, these species occupy the epi-, meta- and

  11. Mercury concentrations in fish from Lake Mead, USA, related to fish size, condition, trophic level, location, and consumption risk.

    PubMed

    Cizdziel, J V; Hinners, T A; Pollard, J E; Heithmar, E M; Cross, C L

    2002-10-01

    Total mercury (Hg) concentrations were determined in the skeletal muscle of 339 fish collected during the fall of 1998 and spring of 1999 from Lake Mead, USA, the nation's largest human-made reservoir. Five species of fish representing a range of trophic levels and the lake's principal game fishes were studied. Hg generally increased with trophic level and fish size. Median Hg concentrations (ng/g wet mass) were 277 in striped bass, 168 in channel catfish, 160 in largemouth bass, 75 in bluegill, and 8 in blue tilapia. Overall, fish from Las Vegas Bay and Boulder Basin had the lowest Hg concentrations, possibly a result of biodilution in this biologically productive area. In general, fish-mercury advisories might include a warning about consuming fillet from emaciated fish, based on the finding that Hg concentrations in 59 striped bass (captured during a scarce-food season) correlated inversely ( r = -0.89, p < 0.001) with a fish nutritional-status factor. This is consistent with starvation-concentration, whereby Hg in fish muscle is lost at a slower rate than the muscle mass. The median concentration found for 139 striped bass corresponds to a recommended risk-based consumption limit of three 8-oz. (227-g) meals per month for a 70-kg adult. Finally, this paper serves as a useful archive for future research and long-term studies of Hg in Lake Mead fish.

  12. Lake trout consumption and recent changes in the fish assemblage of Flaming Gorge Reservoir

    SciTech Connect

    Yule, D.L. ); Luecke, C. )

    1993-11-01

    Bioenergetics modeling was used to quantify the consumption dynamics of lake trout Salvelinus namaycush in Flaming Gorge Reservoir, Utah-Wyoming. Analysis of diet and population estimates of different size-classes of lake trout indicated that kokanees Oncorhynchus nerka made up the greatest proportion of prey biomass. Examination of growth rates of forage fish and predator-prey size ratios indicated that Utah chub Gila atraria were more vulnerable than kokanees to lake trout predation. Utah chub grow slower than kokanees and thus were susceptible to piscivores over a longer age span. The authors conclude the kokanees will make up an even large proportion of the pelagic fish assemblage of Flaming Gorge Reservoir in future years. 44 refs., 5 figs., 4 tabs.

  13. Seasonal consumption of Hemimysis anomala by fish in southeastern Lake Ontario, 2009-2010

    USGS Publications Warehouse

    Lantry, B.F.; Gumtow, C.F.; Walsh, M.G.; Weidel, B.C.; Boscarino, B.T.; Rudstam, L. G.

    2012-01-01

    We investigated the seasonal occurrence of Hemimysis anomala in the diets of fish that prey on macroinvertebrates at two sites with established Hemimysis populations east of Oswego, NY, during 2009-2010. In 2009, we examined 320 stomachs from 10 species and found Hemimysis only in alewife (Alosa pseudoharengus), rockbass (Ambloplites rupestris), and yellow perch (Perca flavescens). Of those species, alewife consumed Hemimysis most frequently and it represented a greater proportion of their diets. During 2009, the dry weight composition of Hemimysis in alewife diets varied seasonally between <1% in June, 5% in July, 98.5% in August, and 18.8% in September. In contrast, we examined 667 stomachs from 15 species in 2010 and observed Hemimysis in only one alewife and two rockbass stomachs. For alewife from September 2009, we found no relationship between predator size and the number of Hemimysis consumed, or between the presence of Hemimysis in fish diets and the presence of other diet taxa or diet diversity. Fish diets collected as bycatch from other assessments revealed large numbers of Hemimysis in fishes that had not previously been observed consuming Hemimysis in Lake Ontario, including cisco (Coregonus artedi) and white perch (Morone americana). Our results indicate Hemimysis consumption by nearshore fish can be high, but that it is variable across seasons and years, and may be most prevalent in fish that feed up in the water column, at or near dark, and have the ability to consume swift moving prey like Mysis diluviana or small fish.

  14. Density, growth and annual food consumption of gobiid fish in the saline Lake Grevelingen, The Netherlands

    NASA Astrophysics Data System (ADS)

    Doornbos, G.; Twisk, F.

    Within the scope of a study of the carbon budget of the 108 km 2 saline Lake Grevelingen, investigations were made on density, mortality, growth and food consumption of the main gobiid fish during the period 1980 to 1982. In August 1980 the O-group of Pomatoschistus minutus was estimated at 424 million individuals (on average 3.9 fishes per m 2) with a biomass of 203 tons FW. In 1981 and 1982 peak numbers were less high. O-group P. microps accounted for 282 million individuals (2.6 fishes per m 2) and 133 tons FW in September 1981. By far the highest density was found in the 0 to 0.6 m zone, 15 common gobies per m 2 (7 g FW·m -2). With approximately 5.1 million individuals (13 tons FW) Gobius niger was most abundant in 1982. For adult G. niger a monthly mortality of 27% was estimated. Mortality rates in P. minutus and P. microps were found to be fairly constant over the year. The estimated rates of annual mortality of 99.9% (˜46% per month) and 99.996% (˜57% per month), respectively, appear to be much higher than recorded for estuarine populations. Approximately 60% of the decline in numbers of demersal gobiid fish could be accounted for by the predation of two species of flatfish and two species of piscivorous birds. Young of the year of over 20 mm total length of both species were first caught in June. At the end of the first growing season, the average length and weight of P. microps was 39 mm and 0.6 g FW. In their second year they attained an average size of 51 mm. In O-group P. minutus, the 1980 and 1981 year classes reached an average length of 45 mm and 57 mm, respectively. In their second year, however, the difference disappeared and the mean length in both classes approximated 62 mm. Juvenile G. niger were first caught in August at a length of approximately 3.5 cm. They attained an average size of 4 to 5 cm in the first year, 8 to 8.5 cm in the second and 11 to 12.5 cm in the third year. The maximum production of P. minutus and P. microps, although

  15. Absence of nonresponse bias in a study of sport-caught Great Lakes fish consumption and conception failure

    SciTech Connect

    Stein, A.D.; Tay, E.; Courval, J.M.

    1999-04-01

    The authors have reported that men`s lifetime sport-caught Great Lakes fish consumption was associated with lifetime prevalence of conception delay or failure. Those cross-sectional data were based on responses to a postal questionnaire. The present study was conducted to evaluate whether nonresponse bias could explain the cross-sectional findings. The authors conducted telephone interviews with 230 men and 38 women who did not respond to the original responders with respect to key demographic, behavioral, and reproductive characteristics. Nonresponders were approximately 1.5 years older at interview, were more likely to be Caucasian, and reported higher incomes than responders. Among men, nonresponders had fished fewer days in the past year. Almost one half of nonresponders reported no fish consumption in the past year, compared to one quarter of responders. Nonresponders were more likely than responders to have ever conceived a live-born child, had more children, and were less likely to intend to have additional children in the next 5 years. Among both responders and nonresponders there was an increased prevalence of a period of conception failure among men who reported consuming greater quantities of sport-caught Great Lakes fish. The study provides support for the cross-sectional analyses presented previously, insofar as nonresponse bias is unlikely to have a major role in the observed association.

  16. Relationship of human levels of lead and cadmium to the consumption of fish caught in and around Lake Coeur d'Alene, Idaho. Final report

    SciTech Connect

    Richter, B.S.; Rondinelli, R.

    1989-09-01

    A pilot exposure study was conducted to determine whether the consumption of fish captured in Lake Coeur d'Alene (LCD), the Coeur d'Alene River, and the adjacent Chain Lakes, could substantially increase lead and cadmium levels in human blood and urine. The goals of the study were: to characterize fish and duck consumption patterns of people living around LCD; and to determine the association between fish and duck consumption and lead/cadmium levels. The lead and cadmium levels among participants living near LCD were within the expected range and are not of any known clinical importance. After adjusting for age and smoking, it was found that persons eating fish or duck were more likely to have higher than the median levels of cadmium in their urine. There were no statistically significant associations between fish or duck consumption and blood levels of lead or cadmium or urine levels of cadmium when adjusted for creatinine.

  17. Heavy metals and arsenic concentrations in ten fish species from the Šalek lakes (Slovenia): assessment of potential human health risk due to fish consumption.

    PubMed

    Al Sayegh Petkovšek, Samar; Mazej Grudnik, Zdenka; Pokorny, Boštjan

    2012-05-01

    The study, which measured the concentrations of Hg, Pb, Cd, Zn and As in various fish tissues (muscle, gill and liver) of 10 fish species (Abramis brama danubii, Alburnus alburnus alburnus, Barbus meridionalis petenyi, Carassius auratius gibelio, Cyprinus carpio, Lepomis gibossus, Leuciscius cephalus cephalus, Perca fluviatilis fluviatilis, Rutilus rutilus, Scardinus erythrophtlalmus erythrophtlalmus) collected in the Šalek lakes, is the first survey regarding metal concentrations in fish species with samples originating from Slovene lakes, while only a limited number of such studies have been carried out in southeastern Europe. Since these lakes are situated in the close vicinity of the largest Slovene thermal power plant, the study provides an insight into the potential impact of increased levels of metals in the environment as well as an estimate of the contamination of fish tissues with metals. Furthermore, it was possible to compare the results obtained with those from other studies regarding metal levels in freshwater fish species. The mean metal concentrations of different tissues irrespective of species varied in the following ranges: Zn 4.31-199 mg/kg ww, Pb 0.01-0.48 mg/kg ww, As 0.02-0.44 mg/kg ww, Hg <0.01-0.31 mg/kg ww, Cd < 0.01-0.19 mg/kg ww. In general, higher contents of Hg were found in muscles and livers than in gills and higher contents of As in gills and livers than in muscles, respectively. The accumulation of Pb and Zn was most pronounced in gills. The result obtained regarding metal concentrations in fish revealed that the ecosystems of the Šalek lakes are not polluted with Hg and Pb, slightly loaded with As and Cd and moderately polluted with Zn. In addition, the potential human health risk due to fish consumption was assessed. This showed that the estimated weekly intakes for all metals were far below provisional permissible tolerable weekly intakes determined by WHO/FAO. The consumption of fish from the Šalek lakes, therefore

  18. Population attributable fraction of incident HIV infections associated with alcohol consumption in fishing communities around Lake Victoria, Uganda

    PubMed Central

    Kiwanuka, Noah; Ssetaala, Ali; Ssekandi, Ismail; Nalutaaya, Annet; Kitandwe, Paul Kato; Ssempiira, Julius; Bagaya, Bernard Ssentalo; Balyegisawa, Apolo; Kaleebu, Pontiano; Hahn, Judith; Lindan, Christina; Sewankambo, Nelson Kaulukusi

    2017-01-01

    Background Although the association between alcohol consumption and HIV risk is well documented, few studies have examined the magnitude of new HIV infections that could be prevented by controlling alcohol use. We report the population attributable fraction (PAF) of incident HIV infections due to alcohol consumption among the HIV high-risk population of fishing communities along Lake Victoria, Uganda. Methods In a community-based cohort study, 1607 HIV sero-negative participants aged 18–49 years were enrolled from eight fishing communities along Lake Victoria, Uganda. At follow up 12 months later, 1288 (80.1%) were seen and interviewed. At baseline and follow-up visits, participants completed interviewer-administered questionnaires on alcohol consumption, demographics, and sexual risk behavior, and were tested for HIV infection. HIV incidence and adjusted incident rate ratios (adjusted IRRs) were estimated using Poisson regression models; the crude and adjusted PAFs of incident HIV infections associated with alcohol consumption were calculated using the Greenland and Drescher method for cohort studies. Results Among the 1288 participants seen at follow up, 53.5% reported drinking alcohol of whom 24.4% drank occasionally (2 days a week or less) and 29.1% drank regularly (3–7 days a week). Forty eight incident HIV infections occurred giving an incidence rate of 3.39/100 person years at-risk (pyar) (95% CI, 2.55–4.49). Compared to non-drinkers, the adjusted IRR of HIV was 3.09 (1.13–8.46) among occasional drinkers and 5.34 (2.04–13.97) among regular drinkers. The overall adjusted PAF of incident HIV infections due alcohol was 64.1 (95% CI; 23.5–83.1); ranging from 52.3 (11.9–74.2) among Muslims to 71.2 (32.6–87.7) for participants who reported ≥ 2 sexual partners in the past 12 months. Conclusion In fishing communities along Lake Victoria, Uganda, 64% of new HIV infections can be attributed to drinking alcohol. Interventions to reduce alcohol

  19. Using Theory to Identify Beliefs Associated with Intentions to Follow Fish Consumption Advisories Among Anglers Living in the Great Lakes Region.

    PubMed

    Niederdeppe, Jeff; Connelly, Nancy A; Labuer, T Bruce; Knuth, Barbara A

    2015-11-01

    Fish consumption advisories are issued by states, tribes, and federal agencies to provide guidance to consumers about eating sport-caught fish potentially affected by chemical contaminants. Previous work has found that while anglers report being aware that advisories are available, awareness and use of specific advisory recommendations is low. This study uses the Integrative Model of Behavioral Prediction (IMBP) to identify beliefs with potential to increase intentions to follow fish consumption advisories in Great Lakes states. We conducted a mail survey of 1,712 licensed anglers in seven of eight Great Lakes states (excluding Ohio) to gauge advisory awareness, cognitive factors influencing fish consumption behaviors (informed by the IMBP), and sociodemographic characteristics. Results show that most anglers reported being generally or vaguely aware of fish consumption advisories and try to follow them, but far fewer report being aware of specific advice needed to decide whether or not to consume different types of sport-caught fish. Informed by the IMBP, we also identify several behavioral, normative, and control beliefs that have sufficient room to change, strong associations with intentions to follow the advisories, and potential to be modified if targeted with strategic risk messages. Targeting these beliefs with strategic communication holds potential to increase the proportion of anglers intending to follow fish consumption advisory recommendations in choosing which fish to eat.

  20. Little Galloo Island, Lake Ontario: A review of nine years of double-crested cormorant diet and fish consumption information

    USGS Publications Warehouse

    Johnson, James H.; Ross, Robert M.; McCullough, Russ D.

    2002-01-01

    The diet of double-crested cormorants (Phalacrocorax auritus) on Little Galloo Island (LGI) in the eastern basin of Lake Ontario has been quantified since 1992. Over the past nine years considerable information has been generated on cormorant feeding ecology through the examination of approximately 12,000 pellets collected on LGI, where three distinct cormorant feeding periods, pre-chick, chick, and post-chick, are delineated by differences in diet composition and daily fish consumption. Yellow perch (Perca flavescens) were the major prey during pre-chick and post-chick feeding periods. Alewife (Alosa pseudoharengus), which move inshore to spawn in mid-June, dominated (>60%) cormorant diets during the chick feeding period. Mean daily fish consumption (14.6) during the pre-chick feeding period was significantly greater than during the chick feeding (9.3) or post-chick feeding (8.0) periods. The proportion of smallmouth bass (Micropterus dolomieu) in the diet increased over the season (0.8% to 7.2%), while the size of bass consumed declined (214 mm to 143 mm). Forage fish (mainly alewife, three-spine sticklebacks [Gasterosteus aculeatus] and minnows) comprised 58% of the diet of LGI cormorants, followed by panfish (37%) (yellow perch, pumpkinseed [Lepomis gibbosus], rock bass [Ambloplites rupestris]) and gamefish (5%) (mostly smallmouth bass). On the average LGI cormorants consumed about 32.8 million fish annually, weighing about 1.4 million kilograms. Cormorants from LGI consumed more biomass of smallmouth bass and yellow perch annually than is taken by sport (bass and yellow perch) and commercial (perch) fishermen.

  1. Global and Local Contributions to Mercury Concentrations in Lake Michigan and Impact on Fish Consumption Advisories

    EPA Science Inventory

    LM2-Mercury, a mercury species mass balance model developed for Lake Michigan, was used to assess mercury cycling in Lake Michigan. A calibrated model (including a hindcast) was used to predict mercury concentrations in the lake based on various sensitivity and management scenari...

  2. Double-crested Cormorant studies at Little Galloo Island, Lake Ontario in 2013: diet composition, fish consumption and the efficacy of management activities in reducing fish predation

    USGS Publications Warehouse

    Johnson, James H.; McCullough, Russell D.; Mazzocchi, Irene

    2014-01-01

    For almost two decades Little Galloo Island (LGI) has supported a large colony of Double-crested Cormorants (Phalacrocorax auritus) in the eastern basin of Lake Ontario. Cormorant nest counts on the island since the early 1990's have averaged 4,297 per year. However, less than 2,000 pairs have nested on the island in three of the past five years. The highest count was reached in 1996 with 8,410 nesting pairs on the island. Johnson et al. (2013) estimated that cormorants from LGI alone have consumed 504 million fish since 1992. The proliferation of cormorants in the eastern basin of Lake Ontario coincided with declines in two important recreational fish species, smallmouth bass (Micropterus dolemieu) and yellow perch (Perca falvescens). Lantry et al. (2002) and Burnett et al. (2002) provide convincing evidence linking cormorant population increases to declining eastern basin smallmouth bass and yellow perch stocks. Decline of these fish stocks was evident only in the eastern basin, suggesting a localized problem, which is consistent with the halo effect where large piscivorous waterbird colonies may deplete local fish stocks (Birt et al. 1987). The year 2013 marked the twenty second consecutive year of study of the food habits and fish consumption of LGI cormorants and the fifteenth consecutive year evaluating the efficacy of management activities to control the reproductive success of cormorants nesting at LGI. The program consists mainly of spraying cormorant eggs with food grade vegetable oil as well as the culling of adult and immature birds. This paper reports the findings of work carried out in 2013 at LGI.

  3. Consumption of Lake Ontario sport fish and the incidence of colorectal cancer in the New York State Angler Cohort Study (NYSACS).

    PubMed

    Callahan, Catherine L; Vena, John E; Green, Joseph; Swanson, Mya; Mu, Lina; Bonner, Matthew R

    2017-04-01

    Fish consumption is hypothesized to reduce the risk of colorectal cancer. Nonetheless, consuming sport fish from the Great Lakes increases exposure to certain persistent organic pollutants, namely polychlorinated biphenyls (PCBs) and organochlorine insecticides, which may increase the risk of cancer. Evidence that exposure to persistent organic pollutants is associated with colorectal cancer is sparse. We examined colorectal cancer incidence in the New York State Angler Cohort Study (NYSACS), a prospective cohort of 17,110 anglers and spouses age 18-40 years at enrollment. In 1991, participants completed a mailed self-administered questionnaire that ascertained the number of years that fish from Lake Ontario were consumed, as well as potential confounders. Forty-one histologically confirmed first primary incident colorectal cancers diagnosed as of December 31, 2008 were identified via the New York State Cancer Registry. Vital status was ascertained by linkage with the Social Security Administration Death File. Rate ratios (RR) and 95% confidence intervals (CI) were calculated with Poisson regression, adjusting for age, pack-years of smoking, and sex. Compared with never consumers, colorectal cancer incidence was statistically non-significantly lower among consumers of Lake Ontario sport fish (RR=0.66; 95% CI: 0.35; 1.24). Incidence of colon cancer was lower among Lake Ontario sport fish consumers (RR=0.45, 95%CI: 0.20; 1.00). We did not observe any evidence of effect measure modification by sex or age. Although consumption of Lake Ontario sport fish may have an inverse association with colorectal cancer risk, inferences are complicated by a small number of cases and a lack of information regarding potential confounders including other dietary factors. However, our results do not provide support for the hypothesis that consumption of contaminated sport fish increases the risk of colorectal cancer.

  4. Little Galloo Island, Lake Ontario: Two decades of studies on the diet, fish consumption, and management of double-crested cormorants

    USGS Publications Warehouse

    Johnson, James H.; McCullough, Russell D.; Farquhar, James F.; Mazzocchi, Irene

    2015-01-01

    The double-crested cormorant (Phalacrocorax auritus) colony at Little Galloo Island, Lake Ontario has been a Great Lakes focal point of controversy regarding cormorant–fish interactions for over two decades. We examined cormorant diet and fish consumption at the colony from 1992 to 2013. During this time period, two events, management actions and round goby (Neogobius melanostomus) invasion, occurred that affected the number of fish consumed by cormorants and their diet composition. The purpose of this study was to evaluate the effects of round goby on the feeding ecology of cormorants and evaluate the efficacy of management actions on meeting cormorant population targets at the colony. Round goby first appeared in the diet in 2004 (0.8%) and within one year were the primary prey (29.3%). The presence of round goby in the diet of cormorants: (1) eliminated seasonal variability in diet composition, (2) reversed seasonal trends in the number of fish consumed daily, (3) increased daily fish consumption, and (4) significantly reduced the consumption of other species including yellow perch and smallmouth bass. Management actions, such as egg oiling and culling, were also effective in reducing nesting activity and the number of cormorant feeding days at the Little Galloo Island colony. There is evidence that the combination of management actions and round goby may have allowed some population recovery of yellow perch and smallmouth bass in eastern Lake Ontario.

  5. Do religion and religiosity have anything to do with alcohol consumption patterns? Evidence from two fish landing sites on Lake Victoria Uganda.

    PubMed

    Tumwesigye, Nazarius M; Atuyambe, Lynn; Kibira, Simon P S; Wabwire-Mangen, Fred; Tushemerirwe, Florence; Wagner, Glenn J

    2013-09-01

    Fish landing sites have high levels of harmful use of alcohol. This paper examines the role of religion and religiosity on alcohol consumption at two fish landing sites on Lake Victoria in Uganda. Questionnaires were administered to randomly selected people at the sites. Dependent variables included alcohol consumption during the previous 30 days, whereas the key independent variables were religion and religiosity. Bivariate and multivariate analysis techniques were applied. People reporting low religiosity were five times more likely to have consumed alcohol (95% confidence interval: 2.45-10.04) compared with those reporting low/average religiosity. Religion and religiosity are potential channels for controlling alcohol use.

  6. Assessment of heavy metals in tilapia fish (Oreochromis niloticus) from the Langat River and Engineering Lake in Bangi, Malaysia, and evaluation of the health risk from tilapia consumption.

    PubMed

    Taweel, Abdulali; Shuhaimi-Othman, M; Ahmad, A K

    2013-07-01

    Concentrations of the heavy metals copper (Cu), cadmium (Cd), zinc (Zn), lead (Pb) and nickel (Ni) were determined in the liver, gills and muscles of tilapia fish from the Langat River and Engineering Lake, Bangi, Selangor, Malaysia. There were differences in the concentrations of the studied heavy metals between different organs and between sites. In the liver samples, Cu>Zn>Ni>Pb>Cd, and in the gills and muscle, Zn>Ni>Cu>Pb>Cd. Levels of Cu, Cd, Zn and Pb in the liver samples from Engineering Lake were higher than in those from the Langat River, whereas the Ni levels in the liver samples from the Langat River were greater than in those from Engineering Lake. Cd levels in the fish muscle from Engineering Lake were lower than in that from the Langat River. Meanwhile, the Cd, Zn and Pb levels in the fish muscle from the Langat River were lower than in that from Engineering Lake, and the Ni levels were almost the same in the fish muscle samples from the two sites. The health risks associated with Cu, Cd, Zn, Pb and Ni were assessed based on the target hazard quotients. In the Langat River, the risk from Cu is minimal compared to the other studied elements, and the concentrations of Pb and Ni were determined to pose the greatest risk. The maximum allowable fish consumption rates (kg/d) based on Cu in Engineering Lake and the Langat River were 2.27 and 1.51 in December and 2.53 and 1.75 in February, respectively. The Cu concentrations resulted in the highest maximum allowable fish consumption rates compared with the other studied heavy metals, whereas those based on Pb were the lowest. A health risk analysis of the heavy metals measured in the fish muscle samples indicated that the fish can be classified at one of the safest levels for the general population and that there are no possible risks pertaining to tilapia fish consumption.

  7. Evaluation of human health risks posed by carcinogenic and non-carcinogenic multiple contaminants associated with consumption of fish from Taihu Lake, China.

    PubMed

    Yu, Yingxin; Wang, Xinxin; Yang, Dan; Lei, Bingli; Zhang, Xiaolan; Zhang, Xinyu

    2014-07-01

    The present study estimated the human daily intake and uptake of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), and toxic trace elements [mercury (Hg), chromium (Cr), cadmium (Cd), and arsenic (As)] due to consumption of fish from Taihu Lake, China, and the associated potential health risks posed by these contaminants. The health risks posed by the contaminants were assessed using a risk quotient of the fish consumption rate to the maximum allowable fish consumption rate considering the contaminants for carcinogenic and non-carcinogenic effect endpoints. The results showed that fish consumption would not pose non-cancer risks. However, some species would cause a cancer risk. Relative risks of the contaminants were calculated to investigate the contaminant which posed the highest risk to humans. As a result, in view of the contaminants for carcinogenic effects, As was the contaminant which posed the highest risk to humans. However, when non-carcinogenic effects of the contaminants were considered, Hg posed the highest risk. The risk caused by PBDEs was negligible. The results demonstrated that traditional contaminants, such as As, Hg, DDTs (dichlorodiphenyltrichloroethane and its metabolites), and PCBs, require more attention in Taihu Lake than the other target contaminants.

  8. MERCURY CONCENTRATIONS IN SKELETAL MUSCLE OF FISH FROM LAKE MEAD, USA, RELATED TO FISH SIZE, CONDITION, TROPHIC LEVEL, LOCATION, AND CONSUMPTION RISK

    EPA Science Inventory

    In this first large-scale study of mercury (Hg) in Lake Mead, USA, the nation's largest man-
    made reservoir, total-Hg concentrations were determined in the skeletal muscle of 339 fish collected during the Fall of 1998 and the Spring of 1999. Five species of fish representing ...

  9. Evaluating microcystin exposure risk through fish consumption.

    PubMed

    Poste, Amanda E; Hecky, Robert E; Guildford, Stephanie J

    2011-07-01

    Microcystin is a cyanobacterial hepatotoxin that is found worldwide, and poses a serious threat to the ecological communities in which it is found as well as to those who rely on these waters for drinking, sanitation, or as a food source. Microcystin is known to accumulate in fish and other aquatic biota, however the prevalence of microcystin in fish tissue and the human health risks posed by microcystin exposure through fish consumption remain poorly resolved. Here we show that microcystin is pervasive in water and fish from several tropical (Ugandan) and temperate (North American) lakes, including lakes that support some of the largest freshwater fisheries in the world. We establish that fish consumption can be an important and sometimes dominant route of microcystin exposure for humans, and can cause consumers to exceed recommended total daily intake guidelines for microcystin. These results highlight the importance of monitoring microcystin concentrations in fish, and the need to consider potential exposure to microcystin through fish consumption in order to adequately assess human exposure risk.

  10. Evaluating microcystin exposure risk through fish consumption

    PubMed Central

    Poste, Amanda E.; Hecky, Robert E.; Guildford, Stephanie J.

    2011-01-01

    Microcystin is a cyanobacterial hepatotoxin that is found worldwide, and poses a serious threat to the ecological communities in which it is found as well as to those who rely on these waters for drinking, sanitation, or as a food source. Microcystin is known to accumulate in fish and other aquatic biota, however the prevalence of microcystin in fish tissue and the human health risks posed by microcystin exposure through fish consumption remain poorly resolved. Here we show that microcystin is pervasive in water and fish from several tropical (Ugandan) and temperate (North American) lakes, including lakes that support some of the largest freshwater fisheries in the world. We establish that fish consumption can be an important and sometimes dominant route of microcystin exposure for humans, and can cause consumers to exceed recommended total daily intake guidelines for microcystin. These results highlight the importance of monitoring microcystin concentrations in fish, and the need to consider potential exposure to microcystin through fish consumption in order to adequately assess human exposure risk. PMID:21671629

  11. Role of socio-cultural and economic factors in cyprinid fish distribution networks and consumption in Lawa Lake region, Northeast Thailand: Novel perspectives on Opisthorchis viverrini transmission dynamics.

    PubMed

    Kim, Christina Sunyoung; Smith, John F; Suwannatrai, Apiporn; Echaubard, Pierre; Wilcox, Bruce; Kaewkes, Sasithorn; Sithithaworn, Paiboon; Sripa, Banchob

    2017-02-16

    Opisthorchis viverrini (Ov) is a fish-borne parasite endemic in parts of Lao PDR, Cambodia, southern Vietnam and Northeast Thailand (Isaan) where an estimated 10 million people are infected. Human Ov infection, associated with hepatobiliary complications, including cholangiocarcinoma (CCA), occurs when infected fish are consumed raw or undercooked, a longstanding cultural tradition in the region. This mixed- methods descriptive study was carried out in Isaan villages around Lawa Lake, Khon Kaen Province, known for their Ov endemicity. Focus group discussions (FGDs) and in depth interviews (IDIs) were used to explore socio-cultural determinants underlying raw fish consumption practices, and global positioning system (GPS) devices to map local fish distribution networks. Qualitative data affirmed major socio-cultural and dietary lifestyle transitions occurring consequent on recent decades of modernization policies and practices, but also the persistence of Isaan traditional raw-fish eating practices and incorrect beliefs about infection risk avoidance. Fish traders/middlemen purchase most of the catch at the lakeshore and play the dominant role in district market fish distribution networks, at least for the larger and less likely infected, fish species. The lower economic value of the small potentially-infected cyprinid fish means local fishermen typically distribute them free, or sell cheaply, to family and friends, effectively concentrating infection risk in already highly Ov infected villages. Our study confirmed the persistence of traditional Isaan raw-fish meal practices, despite major ongoing socio-cultural lifestyle transitions and decades of Ov infection health education programs. We contend that diffuse socio-cultural drivers underpin this practice, including its role as a valued cultural identity marker. A "fish economics" factor was also evident in the concentration of more likely infected fish back into local villages due to their low economic value at

  12. Double-crested cormorant studies at Little Galloo Island, Lake Ontario in 2008: Diet composition, fish consumption and the efficacy of management activities in reducing fish predation

    USGS Publications Warehouse

    Johnson, James H.; McCullough, Russell D.; Farquhar, James F.

    2008-01-01

    The year 2008 marked the seventeenth consecutive year of study of the food habits and fish consumption of LGI cormorants, and represented the tenth consecutive year evaluating the efficacy of management activities to control the reproductive success of cormorants nesting at LGI. The program consists mainly of spraying cormorant eggs with oil as well as the culling of adult and immature birds.This paper reports the findings of work carried outin 2008 at LGI.

  13. Which Fish Should I Eat? Perspectives Influencing Fish Consumption Choices

    PubMed Central

    Choi, Anna L.; Karagas, Margaret R.; Mariën, Koenraad; Rheinberger, Christoph M.; Schoeny, Rita; Sunderland, Elsie; Korrick, Susan

    2012-01-01

    Background: Diverse perspectives have influenced fish consumption choices. Objectives: We summarized the issue of fish consumption choice from toxicological, nutritional, ecological, and economic points of view; identified areas of overlap and disagreement among these viewpoints; and reviewed effects of previous fish consumption advisories. Methods: We reviewed published scientific literature, public health guidelines, and advisories related to fish consumption, focusing on advisories targeted at U.S. populations. However, our conclusions apply to groups having similar fish consumption patterns. Discussion: There are many possible combinations of matters related to fish consumption, but few, if any, fish consumption patterns optimize all domains. Fish provides a rich source of protein and other nutrients, but because of contamination by methylmercury and other toxicants, higher fish intake often leads to greater toxicant exposure. Furthermore, stocks of wild fish are not adequate to meet the nutrient demands of the growing world population, and fish consumption choices also have a broad economic impact on the fishing industry. Most guidance does not account for ecological and economic impacts of different fish consumption choices. Conclusion: Despite the relative lack of information integrating the health, ecological, and economic impacts of different fish choices, clear and simple guidance is necessary to effect desired changes. Thus, more comprehensive advice can be developed to describe the multiple impacts of fish consumption. In addition, policy and fishery management inter-ventions will be necessary to ensure long-term availability of fish as an important source of human nutrition. PMID:22534056

  14. Lakewide estimates of alewife biomass and Chinook salmon abundance and consumption in Lake Ontario, 1989–2005: implications for prey fish sustainability

    USGS Publications Warehouse

    Murry, Brent A.; Connerton, Michael J.; O'Gorman, Robert; Stewart, Donald J.; Ringlerd, Neil H.

    2010-01-01

    Stocking levels of Chinook salmon Oncorhynchus tshawytscha for Lake Ontario have been highly controversial since the early 1990s, largely because of uncertainties about lakewide abundance and rates of prey consumption. Previous estimates have focused on years before 1995; since then, however, the Lake Ontario ecosystem has undergone substantial changes, and there is new evidence of extensive natural recruitment. Presented here are new abundance estimates of Chinook salmon and alewives Alosa pseudoharengus in Lake Ontario and a reevaluation of the potential risk of alewife population collapse. We found that Lake Ontario has been supporting, on average (1989–2005), 1.83 × 106 (range, 1.08 × 106 to 3.24 × 106) Chinook salmon of ages 1–4, amounting to a mean annual biomass of 11.33 × 103 metric tons (range, 5.83 × 103 to 23.04 × 103 metric tons). During the same period (1989–2005), the lake supported an alewife biomass of 173.66 × 103 metric tons (range, 62.37 × 103 to 345.49 × 103 metric tons); Chinook salmon of ages 1–4 consumed, on average, 22% (range, 11–44%) of the alewife biomass annually. Because our estimates probably underestimate total consumption and because Chinook salmon are only one of several salmonine species that depend on alewives, predation pressure on the Lake Ontario alewife population may be high enough to raise concerns about long-term stability of this predator–prey system.

  15. Contaminants in fish tissue from US lakes and reservoirs: A ...

    EPA Pesticide Factsheets

    An unequal probability design was used to develop national estimates for 268 persistent, bioaccumulative, and toxic chemicals in fish tissue from lakes and reservoirs of the conterminous United States (excluding the Laurentian Great Lakes and Great Salt Lake). Predator (fillet) and bottom-dweller (whole-body) composites were collected from 500 lakes selected randomly from the target population of 147,343 lakes in the lower 48 states. Each of these composite types comprised nationally representative samples whose results were extrapolated to the sampled population of an estimated 76,559 lakes for predators and 46,190 lakes for bottom dwellers. Mercury and PCBs were detected in all fish samples. Dioxins and furans were detected in 81% and 99% of predator and bottom-dweller samples, respectively. Cumulative frequency distributions showed that mercury concentrations exceeded the EPA 300 ppb mercury fish tissue criterion at nearly half of the lakes in the sampled population. Total PCB concentrations exceeded a 12 ppb human health risk-based consumption limit at nearly 17% of lakes, and dioxins and furans exceeded a 0.15 ppt (toxic equivalent or TEQ) risk-based threshold at nearly 8% of lakes in the sampled population. In contrast, 43 target chemicals were not detected in any samples. No detections were reported for nine organophosphate pesticides, one PCB congener, 16 polycyclic aromatic hydrocarbons, or 17 other semivolatile organic chemicals. An unequal prob

  16. 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.

  17. Persistent Organohalogens in Paired Fish Fillet and Eggs: Implications for Fish Consumption Advisories.

    PubMed

    Zhang, Xianming; Gandhi, Nilima; Bhavsar, Satyendra P

    2016-04-13

    Fish consumption is associated with both health benefits from high-quality proteins, minerals, vitamins, and fatty acids and risks from contaminants in fish. Fish consumption advisories are issued by many government agencies to keep exposure to contaminants at a safe level. Such advisories are typically based on fillets and neglect consumption of other fish parts such as eggs by certain subpopulations. To evaluate potential for dietary exposure to toxic organic chemicals via fish eggs, we analyzed polybrominated diphenyl ethers (PBDEs), polychlorinated naphthalenes (PCNs), dioxin-like polychlorinated biphenyls (dlPCBs), and polychlorinated dibenzodioxins/furans (PCDD/Fs) in paired fillet and eggs of fish from a tributary to Lake Ontario, one of the North American Great Lakes. All wet weight based concentrations in fish eggs were statistically higher than in the paired fillet samples. In fish eggs, concentrations of Σ14PBDEs, Σ14PCNs, and Σ12dlPCBs were 41-118, 0.3-1.7, and 30-128 ng/g wet weight (ww), respectively; Σ3PCDD/Fs and total (dlPCB+ PCDD/Fs) toxic equivalents (TEQs) were 4-22 and 9-54 pg/g ww, respectively. In fillet samples, Σ14PBDEs, Σ14PCNs, and Σ12dlPCBs were 4-116, 0.05-0.66, and 6-85 ng/g, respectively; Σ3PCDD/Fs and TEQs were 2-10 and 3.4-31 pg/g ww, respectively. In contrast, the fillets had higher lipid normalized concentrations than the paired egg samples, suggesting that these chemicals did not reach equilibrium between the fillets and eggs. Accordingly, measured concentrations in eggs or empirical relationship with fillet rather than prediction from equilibrium partitioning model should be used to evaluate contaminant exposure via consumption of fish eggs. For fatty fish from the lower Great Lakes area, we suggest one fillet meal be reduced from the advised fish consumption frequency for consumptions of 207 ± 37, 39 ± 2, 105 ± 51, and 119 ± 9 g fish eggs of brown trout, Chinook salmon, Coho salmon, and rainbow trout, respectively.

  18. Fish consumption and track to a fish feed formulation

    NASA Astrophysics Data System (ADS)

    Cai-Juan, Soong; Ramli, Razamin; Rahman, Rosshairy Abdul

    2015-12-01

    Strategically located in the equator, Malaysia is blessed with plenty of fish supply. The high demand in fish consumption has helped the development in the fishery industry and provided numerous jobs in the secondary sector, contributing significantly to the nation's income. A survey was conducted to understand the trend of current demands for fish for the purpose of designing a feed formulation, which is still limited in this area of study. Results showed that grouper fish in restaurants commanded a very high price compared to other species of fish. Tiger grouper gained the highest demand in most restaurants, while giant grouper had the highest price in restaurants. Due to the demand and challenges to culture this type of fish, a framework for fish feed formulation is proposed. The formulation framework when materialized could be an alternative to the use of trash fish as the feed for grouper.

  19. Fish consumption, methylmercury and child neurodevelopment

    PubMed Central

    Oken, Emily; Bellinger, David C.

    2008-01-01

    Purpose of review To summarize recent evidence regarding associations of early life exposure to mercury from maternal fish consumption during pregnancy, thimerosal in vaccines and dental amalgam with child neurodevelopment. Recent findings Recent publications have built upon previous evidence demonstrating mild detrimental neurocognitive effects from prenatal methylmercury exposure from maternal fish consumption during pregnancy. New studies examining the effects of prenatal fish consumption as well as methylmercury suggest there are benefits from prenatal fish consumption, but also that consumption of fish high in mercury should be avoided. Future studies incorporating information on both the methylmercury and the docosahexaenoic acid contained within fish will help to refine recommendations to optimize outcomes for mothers and children. Additional recent studies have supported the safety of vaccines containing thimerosal and of dental amalgam for repair of dental caries in children. Summary Exposure to mercury may harm child development. Interventions intended to reduce exposure to low levels of mercury in early life must, however, be carefully evaluated in consideration of the potential attendant harm from resultant behavior changes, such as reduced docosahexaenoic acid exposure from lower seafood intake, reduced uptake of childhood vaccinations and suboptimal dental care. PMID:18332715

  20. Organotin intake through fish consumption in Finland

    SciTech Connect

    Airaksinen, Riikka; Rantakokko, Panu; Turunen, Anu W.; Vartiainen, Terttu; Vuorinen, Pekka J.; Lappalainen, Antti; Vihervuori, Aune; Mannio, Jaakko; Hallikainen, Anja

    2010-08-15

    Background: Organotin compounds (OTCs) are a large class of synthetic chemicals with widely varying properties. Due to their potential adverse health effects, their use has been restricted in many countries. Humans are exposed to OTCs mostly through fish consumption. Objectives: The aim of this study was to describe OTC exposure through fish consumption and to assess the associated potential health risks in a Finnish population. Methods: An extensive sampling of Finnish domestic fish was carried out in the Baltic Sea and freshwater areas in 2005-2007. In addition, samples of imported seafood were collected in 2008. The chemical analysis was performed in an accredited testing laboratory during 2005-2008. Average daily intake of the sum of dibutyltin (DBT), tributyltin (TBT), triphenyltin (TPhT) and dioctyltin (DOT) ({Sigma}OTCs) for the Finnish population was calculated on the basis of the measured concentrations and fish consumption rates. Results: The average daily intake of {Sigma}OTCs through fish consumption was 3.2 ng/kg bw day{sup -1}, which is 1.3% from the Tolerable Daily Intake (TDI) of 250 ng/kg bw day{sup -1} set by the European Food Safety Authority. In total, domestic wild fish accounted for 61% of the {Sigma}OTC intake, while the intake through domestic farmed fish was 4.0% and the intake through imported fish was 35%. The most important species were domestic perch and imported salmon and rainbow trout. Conclusions: The Finnish consumers are not likely to exceed the threshold level for adverse health effects due to OTC intake through fish consumption.

  1. RISK COMMUNICATION TOOLS FOR FISH CONSUMPTION ADVISORIES

    EPA Science Inventory

    In EPA's Mercury Report to Congress an important finding ws that certain populations of subsistence fishermen are at high risk for methyl mercury toxicity because of their high consumption of contaminated fish. Often health risks of Persistent Bioaccumulative Toxicants (PBT) such...

  2. FISH CONSUMPTION, METHYLMERCURY, AND HUMAN HEART DISEASE.

    SciTech Connect

    LIPFERT, F.W.; SULLIVAN, T.M.

    2005-09-21

    Environmental mercury continues to be of concern to public health advocates, both in the U.S. and abroad, and new research continues to be published. A recent analysis of potential health benefits of reduced mercury emissions has opened a new area of public health concern: adverse effects on the cardiovascular system, which could account for the bulk of the potential economic benefits. The authors were careful to include caveats about the uncertainties of such impacts, but they cited only a fraction of the applicable health effects literature. That literature includes studies of the potentially harmful ingredient (methylmercury, MeHg) in fish, as well as of a beneficial ingredient, omega-3 fatty acids or ''fish oils''. The U.S. Food and Drug Administration (FDA) recently certified that some of these fat compounds that are primarily found in fish ''may be beneficial in reducing coronary heart disease''. This paper briefly summarizes and categorizes the extensive literature on both adverse and beneficial links between fish consumption and cardiovascular health, which are typically based on studies of selected groups of individuals (cohorts). Such studies tend to comprise the ''gold standard'' of epidemiology, but cohorts tend to exhibit a great deal of variability, in part because of the limited numbers of individuals involved and in part because of interactions with other dietary and lifestyle considerations. Note that eating fish will involve exposure to both the beneficial effects of fatty acids and the potentially harmful effects of contaminants like Hg or PCBs, all of which depend on the type of fish but tend to be correlated within a population. As a group, the cohort studies show that eating fish tends to reduce mortality, especially due to heart disease, for consumption rates up to about twice weekly, above which the benefits tend to level off. A Finnish cohort study showed increased mortality risks in the highest fish-consuming group ({approx}3 times

  3. Levels of nutrients in relation to fish consumption among older male anglers in Wisconsin

    PubMed Central

    Christensen, Krista Y.; Thompson, Brooke A.; Werner, Mark; Malecki, Kristen; Imm, Pamela; Anderson, Henry A.

    2016-01-01

    Fish are an important source of nutrients including omega-3 fatty acids, which may reduce risk of adverse health outcomes such as cardiovascular disease; however, fish may also contain significant amounts of environmental pollutants. The Wisconsin Departments of Health Services and Natural Resources developed a survey instrument, along with a strategy to collect human biological samples to assess the risks and benefits associated with long-term fish consumption among older male anglers in Wisconsin. The target population was men aged 50 years and older, who fish Wisconsin waters and live in the state of Wisconsin. Participants provided blood and hair samples and completed a detailed (paper) questionnaire, which included questions on basic demographics, health status, location of catch and species of fish caught/eaten, consumption of locally caught and commercially purchased fish, and awareness and source of information for local and statewide consumption guidelines. Biological samples were used to assess levels of docosahexaenoic acid (DHA), docosapentaenoic acid (DPA), eicosapentaenoic acid (EPA); vitamin D; and selenium in blood. Quantile regression analysis was used to investigate the associations between biomarker levels and self-reported consumption of fish from the Great Lakes and other areas of concern, other locally caught fish, and commercially purchased fish (meals per year). Respondents were largely non-Hispanic white men in their 60’s with at least some college education, and about half were retired. Fish consumption was high (median of 54.5 meals per year), with most fish meals coming from locally-caught fish. Multivariate regression models showed that the effect of supplement use was much greater than that of fish consumption, on nutrient levels, although consumption of fish from the Great Lakes and areas of concern was significantly associated with higher levels of vitamin D even after controlling for supplement usage. PMID:26296180

  4. Rodent neurotoxicity bioassays for screening contaminated Great Lakes fish

    SciTech Connect

    Beattie, M.K.; Hoffman, R.; Gerstenberger, S.; Dellinger, J.A.

    1996-03-01

    Standard laboratory rat neurotoxicity protocols were used to study the consequences resulting from the consumption of walleye (Stizostedion vitreum), whitefish (Coregonus clupeaformis), and lake trout (Salvelinus namaycush) from Lake Superior (LS) and the consumption of carp (Cyprinus carpio) from Little Lake Butte des Morte (LLBM) near Oshkosh, Wisconsin, USA. Two 90-d subchronic studies are described, including a 45-d exposure to fish diets using male Sprague-Dawley hooded rats, and a 90-d exposure to fish diets using female rats of the same species. Behavioral alterations were tested using a battery of behavioral tests. In addition, pharmacologic challenges using apomorphine and D-amphetamine were administered to the rats to reveal latent neurotoxic effects. Cumulative fish consumption data were recorded daily, weight gain recorded weekly, and behavior data collected prior to exposure, and on days 7, 14, 55 {+-} 2, 85 {+-} 2. Motor activity data were collected on days 30 {+-} 2, 60 {+-} 2, and 90 {+-} 2 of the feeding protocols. Brain tissue from rodents fed these fish were subsequently analyzed for either mercury (Hg) or polychlorinated biphenyls (PCB). Mercury concentrations were increased in the brains of the walleye-fed rats, and PCB concentrations ranged from 0.5 nl/L to 10 nl/L in the brains of rats fed carp from LLBM, a Lake Michigan tributary. Adult male rats fed LLBM carp for 45 d exhibited the greatest behavior responses to the dopaminergic agonist apomorphine on the accelerating rotarod, although these differences were not significant. The 90-d exposure of LS walleye or Hg-spiked LS walleye resulted in behavior alterations on tactile startle response and second footsplay. D-Amphetamine challenge caused changes in tactile startle response, second footsplay, and accelerating rotarod performance after consuming walleye diets. Rats fed LLBM carp had altered behavioral responses to apomorphine on the accelerating rotarod.

  5. Influence of fish size and sex on mercury/PCB concentration: importance for fish consumption advisories.

    PubMed

    Gewurtz, Sarah B; Bhavsar, Satyendra P; Fletcher, Rachael

    2011-02-01

    Fish advisories for polychlorinated biphenyls (total-PCBs) and mercury are often given on a length-specific basis and fish sex is usually not considered. The relationship between concentration and length is well established for mercury, however its suitability for total-PCBs and the influence of sex over the large scale covered by most monitoring programs is not well known. Here we use what is perhaps the largest consistent sport fish contaminant dataset to evaluate the relationship between total-PCB/mercury and length and sex. We evaluated seven of the most commonly consumed fishes from the Canadian Great Lakes and two Ontario (Canada) inland lakes. For mercury, the relationship between concentration and length was significant (p<0.05) in most fish species and locations. For total-PCB, this relationship was also generally significant in Chinook salmon and lake trout, which are the species with the most advisories for this compound. In contrast, significant relationships were found less often for whitefish, northern pike, smallmouth bass, walleye, and especially yellow perch. However, mercury usually drives fish consumption advisories for these species. Overall, our results support the protocol of issuing contaminant advice on a length-specific basis in fish monitoring programs with reasonable confidence when at least a moderate number of samples over the natural size range of a species are included in the analysis. Sex differences were common for walleye (males>females, p<0.05) but not other species, suggesting that an equal number of male and female walleye should be used in deriving fish advisories for walleye.

  6. Fish Consumption Patterns and Mercury Advisory Knowledge Among Fishers in the Haw River Basin

    PubMed Central

    Johnston, Jill E.; Hoffman, Kate; Wing, Steve; Lowman, Amy

    2016-01-01

    BACKGROUND Fish consumption has numerous health benefits, with fish providing a source of protein as well as omega-3 fatty acids. However, some fish also contain contaminants that can impair human health. In North Carolina, the Department of Health and Human Services has issued fish consumption advisories due to methylmercury contamination in fish. Little is known about local fishers’ consumption patterns and advisory adherence in North Carolina. METHODS We surveyed a consecutive sample of 50 fishers (74.6% positive response rate) who reported eating fish caught from the Haw River Basin or Jordan Lake. They provided information on demographic characteristics, species caught, and the frequency of local fish consumption. Additionally, fishers provided information on their knowledge of fish consumption advisories and the impact of those advisories on their fishing and fish consumption patterns. RESULTS The majority of participants were male (n = 44) and reported living in central North Carolina. Catfish, crappie, sunfish, and large-mouth bass were consumed more frequently than other species of fish. Of the fishers surveyed, 8 reported eating more than 1 fish meal high in mercury per week, which exceeds the North Carolina advisory recommendation. Most participants (n = 32) had no knowledge of local fish advisories, and only 4 fishers reported that advisories impacted their fishing practices. LIMITATIONS We sampled 50 fishers at 11 locations. There is no enumeration of the dynamic population of fishers and no way to assess the representativeness of this sample. CONCLUSIONS Additional outreach is needed to make local fishers aware of fish consumption advisories and the potential health impacts of eating high-mercury fish, which may also contain other persistent and bioaccumulative toxins. PMID:26763238

  7. Egg fatty acid composition from lake trout fed two Lake Michigan prey fish species.

    USGS Publications Warehouse

    Honeyfield, D.C.; Fitzsimons, J.D.; Tillitt, D.E.; Brown, S.B.

    2009-01-01

    We previously demonstrated that there were significant differences in the egg thiamine content in lake trout Salvelinus namaycush fed two Lake Michigan prey fish (alewife Alosa pseudoharengus and bloater Coregonus hoyi). Lake trout fed alewives produced eggs low in thiamine, but it was unknown whether the consumption of alewives affected other nutritionally important components. In this study we investigated the fatty acid composition of lake trout eggs when females were fed diets that resulted in different egg thiamine concentrations. For 2 years, adult lake trout were fed diets consisting of four combinations of captured alewives and bloaters (100% alewives; 65% alewives, 35% bloaters; 35% alewives, 65% bloaters; and 100% bloaters). The alewife fatty acid profile had higher concentrations of arachidonic acid and total omega-6 fatty acids than the bloater profile. The concentrations of four fatty acids (cis-13, 16-docosadienoic, eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids) were higher in bloaters than in alewives. Although six fatty acid components were higher in lake trout eggs in 2001 than in 2000 and eight fatty acids were lower, diet had no effect on any fatty acid concentration measured in lake trout eggs in this study. Based on these results, it appears that egg fatty acid concentrations differ between years but that the egg fatty acid profile does not reflect the alewife-bloater mix in the diet of adults. The essential fatty acid content of lake trout eggs from females fed alewives and bloaters appears to be physiologically regulated and adequate to meet the requirements of developing embryos.

  8. Geographical distribution of perfluorinated compounds in fish from Minnesota lakes and rivers.

    PubMed

    Delinsky, Amy D; Strynar, Mark J; McCann, Patricia J; Varns, Jerry L; McMillan, Larry; Nakayama, Shoji F; Lindstrom, Andrew B

    2010-04-01

    In response to growing interest in human exposure to perfluorinated compounds (PFCs), the state of Minnesota measured and reported PFC concentrations in fish collected from the Minneapolis-St. Paul area. To better determine the geographical distribution of PFC contamination throughout Minnesota, fish were collected from 59 lakes throughout the state and several areas along the Mississippi River. Composite fish samples were analyzed for 10 PFC analytes by solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC/MS/MS). PFOS (perfluorooctanesulfonate) was the most commonly detected PFC, occurring in 73% of fish from the Mississippi River but only 22% of fish from lakes. Fish from Mississippi River Pool 2 near the Minneapolis-St. Paul area had the highest levels of PFOS, whereas locations upstream had PFOS concentrations below 40 ng/g, the concentration at which Minnesota issues "one meal per week" fish consumption advice. Fish from most Minnesota lakes tested (88%) had PFOS concentrations below 3 ng/g. Two lakes, McCarrons and Zumbro, contained fish with PFOS levels above 40 ng/g. The results reported here will help researchers to better understand the extent of PFC contamination in Minnesota fish and evaluate potential sources of contamination and will provide a basis for comprehensive fish consumption advice.

  9. Modeling prey consumption by native and non-native piscivorous fishes: implications for competition and impacts on shared prey in an ultraoligotrophic lake in Patagonia

    USGS Publications Warehouse

    Juncos, Romina; Beauchamp, David A.; Viglianoc, Pablo H.

    2013-01-01

    We examined trophic interactions of the nonnative salmonids Rainbow Trout Oncorhynchus mykiss, Brown Trout Salmo trutta, and Brook Trout Salvelinus fontinalisand the main native predator Creole Perch Percichthys trucha in Lake Nahuel Huapi (Patagonia, Argentina) to determine the relative impact of each predator on their forage base and to evaluate the potential vulnerability of each predator to competitive impacts by the others. Using bioenergetics simulations, we demonstrated the overall importance of galaxiids and decapods to the energy budgets of nonnative salmonids and Creole Perch. Introduced salmonids, especially Rainbow Trout, exerted considerably heavier predatory demands on shared resources than did the native Creole Perch on both a per capita basis and in terms of relative population impacts. Rainbow Trout consumed higher quantities and a wider size range of Small Puyen (also known as Inanga) Galaxias maculatus than the other predators, including early pelagic life stages of that prey; as such, this represents an additional source of mortality for the vulnerable early life stages of Small Puyen before and during their transition from pelagic to benthic habitats. All predators were generally feeding at high feeding rates (above 40% of their maximum physiological rates), suggesting that competition for prey does not currently limit either Creole Perch or the salmonids in this lake. This study highlights the importance of keystone prey for the coexistence of native species with nonnative top predators. It provides new quantitative and qualitative evidence of the high predation pressure exerted on Small Puyen, the keystone prey species, during the larval to juvenile transition from pelagic to littoral-benthic habitat in Patagonian lakes. This study also emphasizes the importance of monitoring salmonid and Creole Perch population dynamics in order to detect signs of potential impacts through competition and shows the need to carefully consider the rationale

  10. Lake Superior Coastal Wetland Fish Assemblages and ...

    EPA Pesticide Factsheets

    The role of the coastal margin and the watershed context in defining the ecology of even very large lakes is increasingly being recognized and examined. Coastal wetlands are both important contributors to the biodiversity and productivity of large lakes and important mediators of the lake-basin connection. We explored wetland-watershed connections and their relationship to wetland function and condition using data collected from 37 Lake Superior wetlands spanning a substantial geographic and geomorphic gradient. While none of these wetlands are particularly disturbed, there were nevertheless clear relationships between watershed landuse and wetland habitat and biota, and these varied consistently across wetland type categories that reflected the strength of connection to the watershed. For example, water clarity and vegetation structure complexity declined with decreasing percent natural land cover, and these effects were strongest in riverine wetlands (having generally large watersheds and tributary-dominated hydrology) and weakest in lagoon wetlands (having generally small watersheds and lake-dominate hydrology). Fish abundance and species richness both increased with decreasing percent natural land cover while species diversity decreased, and again the effect was strongest in riverine wetlands. Lagoonal wetlands, which lack any substantial tributary, consistently harbored the fewest species of fish and a composition different from the more watershed-lin

  11. Polychlorinated biphenyls and omega-3 fatty acid exposure from fish consumption, and thyroid cancer among New York anglers.

    PubMed

    Haslam, Alyson; Robb, Sara Wagner; Bonner, Matthew R; Lindblad, William; Allegra, Joey; Shen, Ye; Vena, John E

    2016-03-01

    Fish from the Great Lakes contain polychlorinated biphenyls (PCBs) which have been shown to disrupt endocrine function and mimic thyroid hormones, but they also contain beneficial omega-3 fatty acids that may offer protection against endocrine cancers. The purpose of this study was to examine the effects of Lake Ontario fish consumption and the estimated consumption of PCBs and omega-3 fatty acids on the risk of thyroid cancer in a group of sport fishermen. Anglers from the New York State Angler Cohort Study were followed for cancer incidence from 1991-2008. Twenty-seven cases of incident thyroid cancer and 108 controls were included in the analyses. Total estimated fish consumption, estimated omega-3 fatty acid consumption, and estimated PCB consumption from Lake Ontario fish were examined for an association with the incidence of thyroid cancer, while matching on sex, and controlling for age and smoking status. Results from logistic regression indicate no significant associations between fish consumption, short-term estimated omega-3 fatty acids, or estimated PCB consumption from Great Lakes fish and the development of thyroid cancer, but it was suggested that long-term omega-3 fatty acid from Great Lakes fish may be protective of the development of thyroid cancer. In conclusion, fish consumption, with the possible concomitant PCBs, from the Great Lakes does not appear to increase the risk of thyroid cancer in New York anglers. Further research is needed in order to separate the individual health effects of PCBs from omega-3 fatty acids contained within the fish.

  12. Status and future of Lake Huron fish communities

    USGS Publications Warehouse

    Ebener, M.P.; Johnson, J.E.; Reid, D.M.; Payne, N.P.; Argyle, R.L.; Wright, G.M.; Krueger, K.; Baker, J.P.; Morse, T.; Weise, J.; Munawar, M.; Edsall, T.; Leach, J.

    1995-01-01

    In 1993, fishery management agencies with jurisdiction over Lake Huron fish populations developed draft fish community objectives in response to the Joint Strategic Plan for Management of Great Lakes Fisheries. The Joint Strategic Plan charged the Great Lakes Fishery Commission sponsored Lake Huron Committee to define objectives for what the fish community of Lake Huron should look like in the future, and to develop means for measuring progress toward the objectives. The overall management objective for Lake Huron is to 'over the next two decades restore an ecologically balanced fish community dominated by top predators and consisting largely of self-sustaining, indigenous and naturalized species and capable of sustaining annual harvests of 8.9 million kg'. This paper represents the first attempt at consolidating current biological information from different management agencies on a lake-wide basis for the purpose of assessing the current status and dynamics of Lake Huron fishes.

  13. Methylmercury exposure in a subsistence fishing community in Lake Chapala, Mexico: an ecological approach

    PubMed Central

    2010-01-01

    Background Elevated concentrations of mercury have been documented in fish in Lake Chapala in central Mexico, an area that is home to a large subsistence fishing community. However, neither the extent of human mercury exposure nor its sources and routes have been elucidated. Methods Total mercury concentrations were measured in samples of fish from Lake Chapala; in sections of sediment cores from the delta of Rio Lerma, the major tributary to the lake; and in a series of suspended-particle samples collected at sites from the mouth of the Lerma to mid-Lake. A cross-sectional survey of 92 women ranging in age from 18-45 years was conducted in three communities along the Lake to investigate the relationship between fish consumption and hair mercury concentrations among women of child-bearing age. Results Highest concentrations of mercury in fish samples were found in carp (mean 0.87 ppm). Sediment data suggest a pattern of moderate ongoing contamination. Analyses of particles filtered from the water column showed highest concentrations of mercury near the mouth of the Lerma. In the human study, 27.2% of women had >1 ppm hair mercury. On multivariable analysis, carp consumption and consumption of fish purchased or captured from Lake Chapala were both associated with significantly higher mean hair mercury concentrations. Conclusions Our preliminary data indicate that, despite a moderate level of contamination in recent sediments and suspended particulate matter, carp in Lake Chapala contain mercury concentrations of concern for local fish consumers. Consumption of carp appears to contribute significantly to body burden in this population. Further studies of the consequences of prenatal exposure for child neurodevelopment are being initiated. PMID:20064246

  14. Lake Erie...Build a Fish to Scale!

    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) name the different parts of a fish; (2) assemble a fish using overlapping overheads to reinforce fish parts; (3) build a fish to scale using jumbo fish puzzle parts; (4) classify…

  15. Serum PCB and DDE levels of frequent Great Lakes sport fish consumers -- A first look

    SciTech Connect

    Hanrahan, L.P.; Falk, C.; Anderson, H.A.; Draheim, L.; Olson, J.; Kanarek, M.S.

    1999-02-01

    Great Lakes (GL) sport fish consumption is a potential human exposure route for polychlorinated biphenyls (PCBs) and dichlorodiphenyl dichloroethene (DDE). Because of fish tissue contamination, frequent consumers of Great Lakes sport caught fish (GLSCF) may be at risk for PCB and DDE accumulation. To examine this problem, the Health Departments of Wisconsin, Illinois, Indiana, Ohio, and Michigan formed a health assessment consortium. Participants were contacted by telephone to complete a detailed demographic and fish consumption survey. Frequent and infrequent GLSCF consumers were identified, and a participant subset was then asked to donate blood for PCB and DDE analysis. Analysis of variance (ANOVA) was done to study exposure group mean differences, while correlation and regression analyses were performed to examine relationships between demographic characteristics, GLSCF consumption, PCB, and DDE body burdens.

  16. Perfluorinated compounds in fish from U.S. urban rivers and the Great Lakes.

    PubMed

    Stahl, Leanne L; Snyder, Blaine D; Olsen, Anthony R; Kincaid, Thomas M; Wathen, John B; McCarty, Harry B

    2014-11-15

    Perfluorinated compounds (PFCs) have recently received scientific and regulatory attention due to their broad environmental distribution, persistence, bioaccumulative potential, and toxicity. Studies suggest that fish consumption may be a source of human exposure to perfluorooctane sulfonate (PFOS) or long-chain perfluorocarboxylic acids. Most PFC fish tissue literature focuses on marine fish and waters outside of the United States (U.S.). To broaden assessments in U.S. fish, a characterization of PFCs in freshwater fish was initiated on a national scale using an unequal probability design during the U.S. Environmental Protection Agency's (EPA's) 2008-2009 National Rivers and Streams Assessment (NRSA) and the Great Lakes Human Health Fish Tissue Study component of the 2010 EPA National Coastal Condition Assessment (NCCA/GL). Fish were collected from randomly selected locations--164 urban river sites and 157 nearshore Great Lake sites. The probability design allowed extrapolation to the sampled population of 17,059 km in urban rivers and a nearshore area of 11,091 km(2) in the Great Lakes. Fillets were analyzed for 13 PFCs using high-performance liquid chromatography tandem mass spectrometry. Results showed that PFOS dominated in frequency of occurrence, followed by three other longer-chain PFCs (perfluorodecanoic acid, perfluoroundecanoic acid, and perfluorododecanoic acid). Maximum PFOS concentrations were 127 and 80 ng/g in urban river samples and Great Lakes samples, respectively. The range of NRSA PFOS detections was similar to literature accounts from targeted riverine fish sampling. NCCA/GL PFOS levels were lower than those reported by other Great Lakes researchers, but generally higher than values in targeted inland lake studies. The probability design allowed development of cumulative distribution functions (CDFs) to quantify PFOS concentrations versus the sampled population, and the application of fish consumption advisory guidance to the CDFs resulted in

  17. Organochlorine pesticides in fish from Taihu Lake, China, and associated human health risk assessment.

    PubMed

    Wang, Deqing; Yu, Yingxin; Zhang, Xinyu; Zhang, Dongping; Zhang, Shaohuan; Wu, Minghong

    2013-12-01

    Because contaminants and nutrients always coexist in fish, the risk from contaminants and the benefit from nutrients, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are also concomitant via fish consumption. To investigate the risk and benefit via fish consumption, concentrations of dichlorodiphenyltrichloroethane and its metabolites (DDTs), and hexachlorocyclohexanes (HCHs) in the whole- and portion-muscles of fish from Taihu Lake, China, were measured. Based on the contaminant data and nutrients from our previous study, and the associated risk and benefit via fish consumption were estimated. The concentrations of DDTs and HCHs in the whole-muscles ranged from 7.8 × 10² to 3.4×10³ pg g⁻¹ ww, and from 67.3 to 300 pg g⁻¹ ww, respectively. Of DDTs and HCHs measured, p,p'-DDE and β-HCH were respectively the most abundant pesticides. The composition profiles of DDTs and HCHs suggested that the pesticides were mainly historical residues. The benefit-risk quotient (BRQ) of EPA+DHA vs. POPs (persistent organic pollutants including data of DDTs, HCHs, and those of polychlorinated biphenyls and polybrominated diphenyl ethers cited from our previous study) via consumption of fish from Taihu Lake was calculated. As a result, to achieve the recommended EPA+DHA intake of 250 mg d⁻¹ for a healthy adult, the consumption of most fish species from the lake can cause cancer and non-cancer risks. However, the fish consumption at the rates of 44.9 g d⁻¹ by Chinese would not lead to the risks for most of the species. The results also suggested that the risk of consuming silver carp was generally lower than other fish species, and those of dorsal muscles were lower than ventral and tail muscles.

  18. Population Density of the Crayfish, Orconectes limosus, in Relation to Fish and Macroinvertebrate Densities in a Small Mesotrophic Lake - Implications for the Lake's Food Web

    NASA Astrophysics Data System (ADS)

    Haertel-Borer, Susanne S.; Zak, Dominik; Eckmann, Reiner; Baade, Ulrich; Hölker, Franz

    2005-12-01

    The population density of Orconectes limosus in a mesotrophic lake was assessed in the context of fish and macroinvertebrate biomasses, and crayfish consumption by fish. The average O. limosus (6 cm total length) abundance and biomass in the littoral zone was 2200 ind ha-1 and 32.2 kg ha1, respectively. O. limosus biomass accounted for a large percentage (49%) of the lake's macroinvertebrate biomass. O. limosus was equal to 35% of the non-predatory fish biomass and to 81% of the predatory fish biomass. O. limosus comprised 15 and 48% of the annual consumption of pike and predatory perch, respectively. Altogether, O. limosus was identified as quantitatively important for the lake's littoral food web, and might also subsidize the pelagic food web. This strengthens the need for an integrated view on lake food webs.

  19. Macroinvertebrates as indicators of fish absence in naturally fishless lakes

    USGS Publications Warehouse

    Schilling, Emily Gaenzle; Loftin, C.S.; Huryn, Alexander D.

    2009-01-01

    1. Little is known about native communities in naturally fishless lakes in eastern North America, a region where fish stocking has led to a decline in these habitats. 2. Our study objectives were to: (i) characterise and compare macroinvertebrate communities in fishless lakes found in two biophysical regions of Maine (U.S.A.): kettle lakes in the eastern lowlands and foothills and headwater lakes in the central and western mountains; (ii) identify unique attributes of fishless lake macroinvertebrate communities compared to lakes with fish and (iii) develop a method to efficiently identify fishless lakes when thorough fish surveys are not possible. 3. We quantified macroinvertebrate community structure in the two physiographic fishless lake types (n = 8 kettle lakes; n = 8 headwater lakes) with submerged light traps and sweep nets. We also compared fishless lake macroinvertebrate communities to those in fish-containing lakes (n = 18) of similar size, location and maximum depth. We used non-metric multidimensional scaling to assess differences in community structure and t-tests for taxon-specific comparisons between lakes. 4. Few differences in macroinvertebrate communities between the two physiographic fishless lake types were apparent. Fishless and fish-containing lakes had numerous differences in macroinvertebrate community structure, abundance, taxonomic composition and species richness. Fish presence or absence was a stronger determinant of community structure in our study than differences in physical conditions relating to lake origin and physiography. 5. Communities in fishless lakes were more speciose and abundant than in fish-containing lakes, especially taxa that are large, active and free-swimming. Families differing in abundance and taxonomic composition included Notonectidae, Corixidae, Gyrinidae, Dytiscidae, Aeshnidae, Libellulidae and Chaoboridae. 6. We identified six taxa unique to fishless lakes that are robust indicators of fish absence: Graphoderus

  20. A history of total mercury in edible muscle of fish from lakes in northern Canada.

    PubMed

    Lockhart, W L; Stern, G A; Low, G; Hendzel, M; Boila, G; Roach, P; Evans, M S; Billeck, B N; DeLaronde, J; Friesen, S; Kidd, K; Atkins, S; Muir, D C G; Stoddart, M; Stephens, G; Stephenson, S; Harbicht, S; Snowshoe, N; Grey, B; Thompson, S; DeGraff, N

    2005-12-01

    Subsistence fishing has been an important source of food for Native People in northern Canada since prehistoric time. Measurements of the levels of mercury in edible muscle of northern fish have been undertaken for over three decades in efforts to evaluate the risks of consuming northern fish. This report summarizes the data obtained from 7974 fish of 25 species from sites distributed from the Yukon to Labrador. The most abundant species were lake trout, lake whitefish, arctic char, walleye, northern pike and burbot. The question being asked was essentially "Are the fish safe to eat?" The results were used to support decisions on fishing and consumption of fish. They were sorted in several ways, into concentration ranges corresponding to human consumption guidelines, into political jurisdictions and into types of bedrock geology. Overall walleye, northern pike and lake trout, usually exceeded the subsistence consumption guideline of 0.2 microg g-1 total mercury and often exceeded the higher guideline of 0.5 microg g-1 total mercury for commercial sales of fish. Mercury in burbot, another facultative predator, was often lower but several still exceeding a guideline. Arctic char collections were mostly from anadromous populations and these had very low levels of mercury, presumably reflecting marine food sources. Lake whitefish were among the cleanest fish examined with 69 of 81 collections falling in the lowest range. Most collections were from sites in sedimentary rock. However a few sites were in metamorphic, intrusive or volcanic rocks and these, taken together, tended to have a higher proportion of sites in the higher ranges of mercury. These results indicate a widespread problem with mercury in subsistence fisheries for predator species of fish with the problem being most problematic for Nunavut.

  1. How can more women of childbearing age be encouraged to follow fish consumption recommendations?

    PubMed

    Connelly, Nancy A; Lauber, T Bruce; Niederdeppe, Jeff; Knuth, Barbara A

    2014-11-01

    Several studies show that most women do not consume enough fish during pregnancy (and afterward) to derive the maximum health benefits for themselves and their babies, according to the USDA guidelines. We engaged in a two-part study to better understand what might be done to encourage women of childbearing age to eat healthy fish-a mail survey of women who recently gave birth in Minnesota, Wisconsin, and Pennsylvania, and six focus groups with women of childbearing age living in the Great Lakes region. Similar to other studies, we found that many women changed their behavior and consumed less fish during pregnancy than before. Most women reported receiving information, primarily during pregnancy, about the types of fish and how much fish to eat. As a result, increasing access to information during pregnancy likely would not result in increasing many women's fish consumption. Based on our examination of factors influencing women to try to follow the recommendations, the strongest connection with trying to follow the recommendations was receiving enough information to decide and believing that eating fish was good for the baby. Focus group participants also reported that messages about the specific health benefits of fish consumption for their children were particularly influential. These findings suggest that refining messages through testing might be a valuable approach toward increasing women's consumption of less-contaminated fish.

  2. Need for improved risk communication of fish consumption advisories to protect maternal and child health: influence of primary informants.

    PubMed

    LePrevost, Catherine E; Gray, Kathleen M; Hernández-Pelletier, Mercedes; Bouma, Brennan D; Arellano, Consuelo; Cope, W Gregory

    2013-04-29

    Fish consumption has established benefits, including the promotion of cardiovascular health and pre- and neonatal brain and eye development, but local freshwater fish may be a source of contaminants that are especially harmful to fetuses and young children, such as the neurotoxic and developmentally toxic methylmercury and polychlorinated biphenyls. Fish consumption advisories may be issued by state health departments to limit human exposure to these and other toxicants. This study examined the efficacy of a sign designed by the North Carolina Division of Public Health that was posted along a reservoir (Badin Lake) in central North Carolina, USA, for increasing anglers' awareness of a fish consumption advisory, with a special focus on anglers who share their catch with women and children. In this study, 109 anglers were interviewed about their awareness of fish consumption advisories in general and their knowledge of the Badin Lake fish advisory in particular. Shore anglers were significantly less likely to be aware of the term "fish consumption advisory" and of the specific advisory for Badin Lake than boat anglers. Although a significant increase in knowledge of the specific fish consumption advisory was found for the entire sample of study participants after the sign intervention, a commensurate increase in knowledge was not found for a subsample of anglers who reported sharing their catch with women and children. Study findings underscore differences in fish consumption advisory awareness among subpopulations. Specifically, the study revealed the importance of characterizing the communication needs of shore anglers and anglers who share their catch with sensitive subpopulations (e.g., women and children) for the creation of more targeted communications of fish consumption advisories.

  3. Childhood Fish Consumption and Learning and Behavioral Disorders

    PubMed Central

    Carwile, Jenny L.; Butler, Lindsey J.; Janulewicz, Patricia A.; Winter, Michael R.; Aschengrau, Ann

    2016-01-01

    Fish is a major source of nutrients critical for brain development during early life. The importance of childhood fish consumption is supported by several studies reporting associations of n-3 polyunsaturated fatty acid (n-3 PUFA) supplementation with better behavior and school performance. However, fish may have a different effect than n-3 PUFA alone due to the neurotoxic effects of methylmercury, a frequent contaminant. We investigated associations of childhood fish consumption with learning and behavioral disorders in birth cohort study of the neurotoxic effects of early life exposure to solvent-contaminated drinking water. Childhood (age 7–12 years) fish consumption and learning and behavioral problems were reported in self-administered questionnaires (age 23–41 at questionnaire completion). Fish consumption was not meaningfully associated with repeating a grade, tutoring, attending summer school, special class placement, or low educational attainment. However, participants who ate fish several times a week had an elevated odds of Attention Deficit Disorder/Attention Deficit Hyperactivity Disorder (odds ratio: 5.2; 95% confidence interval: 1.5–18) compared to participants who did not eat fish. While these findings generally support the safety of the observed level of fish consumption, the absence of a beneficial effect may be attributed to insufficient fish intake or the choice of relatively low n-3 PUFA fish. PMID:27827868

  4. Growth and diet of fish in Waldo Lake, Oregon

    USGS Publications Warehouse

    Swanson, Nicola L.; Liss, W.J.; Ziller, Jeffrey S.; Wade, M.; Gresswell, R.E.

    2000-01-01

    Waldo Lake, located in the Oregon Cascades, is considered to be one of the most dilute lakes in the world. Even with low nutrient concentrations and sparse populations of zooplankton, introduced fish in the lake are large in size and in good condition when compared to fish from other lakes. This apparent anomaly is due to the availability of benthic macroinvertebrates. Taxa found in the stomach contents offish captured in Waldo Lake consist primarily of Chironomidae larvae and pupae, Trichoptera larvae and pupae, amphipods, Ephemeroptera larvae, and Odonata larvae.

  5. Consumption of PCB-contaminated sport fish and risk of spontaneous fetal death

    SciTech Connect

    Mendola, P.; Buck, G.M.; Vena, J.E.; Zielezny, M.; Sever, L.E.

    1995-05-01

    Spontaneous fetal death has been observed among various mammalian species after exposure to polychlorinated biphenyls (PCBs). Our exposure-based cohort study assessed the relationship between consumption of PCB-contaminated Lake Ontario sport fish and spontaneous fetal death using 1820 multigravid fertile women from the 1990-1991 New York State Angler Cohort Study. Fish consumption data were obtained from food frequency questionnaires and history of spontaneous fetal death from live birth certificates. Analyses were stratified by number of prior pregnancies and controlled for smoking and maternal age. No significant increases in risk for fetal death were observed across four measures of exposure: a lifetime estimate of PCB exposure based on species-specific PCB levels; the number of years of fish consumption; kilograms of sport fish consumed in 1990-1991; and a lifetime estimate of kilograms eaten. A slight risk reduction was seen for women with two prior pregnancies at the highest level of PCB exposure (odds ratio = 0.36; 95% CI, 0.14-0.92) and for women with three or more prior pregnancies with increasing years of fish consumption (odds ratio = 0.97; 95% CI, 0.94-0.99). These findings suggest that consumption of PCB-contaminated sport fish does not increase the risk of spontaneous fetal death. 50 refs., 2 tabs.

  6. Consumption of PCB-contaminated sport fish and risk of spontaneous fetal death.

    PubMed Central

    Mendola, P; Buck, G M; Vena, J E; Zielezny, M; Sever, L E

    1995-01-01

    Spontaneous fetal death has been observed among various mammalian species after exposure to polychlorinated biphenyls (PCBs). Our exposure-based cohort study assessed the relationship between consumption of PCB-contaminated Lake Ontario sport fish and spontaneous fetal death using 1820 multigravid fertile women from the 1990-1991 New York State Angler Cohort Study. Fish consumption data were obtained from food frequency questionnaires and history of spontaneous fetal death from live birth certificates. Analyses were stratified by number of prior pregnancies and controlled for smoking and maternal age. No significant increases in risk for fetal death were observed across four measures of exposure: a lifetime estimate of PCB exposure based on species-specific PCB levels; the number of years of fish consumption; kilograms of sport fish consumed in 1990-1991; and a lifetime estimate of kilograms eaten. A slight risk reduction was seen for women with two prior pregnancies at the highest level of PCB exposure (odds ratio = 0.36; 95% CI, 0.14-0.92) and for women with three or more prior pregnancies with increasing years of fish consumption (odds ratio = 0.97; 95% CI, 0.94-0.99). These findings suggest that consumption of PCB-contaminated sport fish does not increase the risk of spontaneous fetal death. PMID:7656880

  7. Modeling tribal exposures to methyl mercury from fish consumption

    EPA Science Inventory

    Exposure assessment and risk management considerations for tribal fish consumption are different than for the general U.S. population because of higher fish intake from subsistence fishing and/or from unique cultural practices. This research summarizes analyses of available data ...

  8. Modeling Tribal Exposures to PCBs from Fish Consumption

    EPA Science Inventory

    Studies have shown that U.S. population continues to be exposed to polychlorinated biphenyls (PCBs), despite the ban ~40 years ago. Fish intake is a major pathway, especially, for high fish-consumption groups. Exposure assessment and risk management considerations for tribal fish...

  9. Knowledge and barriers relating to fish consumption in older Australians.

    PubMed

    Grieger, Jessica A; Miller, Michelle; Cobiac, Lynne

    2012-10-01

    Among 854 Australians ≥ 51 years of age, this cross-sectional survey explored knowledge regarding finfish consumption, sources of information on fish and omega 3 fatty acids, what barriers limit finfish consumption and what factors predict its consumption. The survey consisted of a validated quantitative fish frequency questionnaire with additional questions on barriers and knowledge relating to finfish. Twelve percent of respondents consumed oily fish ≥ 2 times per week. Cost was the most frequently (37%) reported barrier for fresh finfish consumption. In multiple regression analysis, respondents' exposure to multiple sources of information (odds ratio (95% confidence interval): 1.135 (1.01, 1.28), who correctly identified the current recommendations for fish consumption; 1.87 (1.13, 3.07), agreed that fish improves general health; 3.57 (1.13, 11.30), and reported fewer barriers towards canned fish consumption; 0.59 (0.41, 0.84) were more likely to consume ≥ 2 servings of fresh finfish per week. Education and health programs need to be readily available highlighting current recommendations for fish consumption and how targets can be achieved. Meal plans with various finfish/seafood and amounts of omega 3 fatty acids required to achieve recommendations, and within a suitable budget, is likely to be an important strategy to target older consumers to increase consumption.

  10. Hydroacoustic estimates of abundance and spatial distribution of pelagic prey fishes in western Lake Superior

    USGS Publications Warehouse

    Mason, Doran M.; Johnson, Timothy B.; Harvey, Chris J.; Kitchell, James F.; Schram, Stephen T.; Bronte, Charles R.; Hoff, MIchael H.; Lozano, Stephen J.; Trebitz, Anett S.; Schreiner, Donald R.; Lamon, E. Conrad; Hrabik, Thomas R.

    2005-01-01

    Lake herring (Coregonus artedi) and rainbow smelt (Osmerus mordax) are a valuable prey resource for the recovering lake trout (Salvelinus namaycush) in Lake Superior. However, prey biomass may be insufficient to support the current predator demand. In August 1997, we assessed the abundance and spatial distribution of pelagic coregonines and rainbow smelt in western Lake Superior by combining a 120 kHz split beam acoustics system with midwater trawls. Coregonines comprised the majority of the midwater trawl catches and the length distributions for trawl caught fish coincided with estimated sizes of acoustic targets. Overall mean pelagic prey fish biomass was 15.56 kg ha−1 with the greatest fish biomass occurring in the Apostle Islands region (27.98 kg ha−1), followed by the Duluth Minnesota region (20.22 kg ha−1), and with the lowest biomass occurring in the open waters of western Lake Superior (9.46 kg ha−1). Biomass estimates from hydroacoustics were typically 2–134 times greater than estimates derived from spring bottom trawl surveys. Prey fish biomass for Lake Superior is about order of magnitude less than acoustic estimates for Lakes Michigan and Ontario. Discrepancies observed between bioenergetics-based estimates of predator consumption of coregonines and earlier coregonine biomass estimates may be accounted for by our hydroacoustic estimates.

  11. Comparing nearshore benthic and pelagic prey as mercury sources to lake fish: the importance of prey quality and mercury content.

    PubMed

    Karimi, Roxanne; Chen, Celia Y; Folt, Carol L

    2016-09-15

    Mercury (Hg) bioaccumulation in fish poses well-known health risks to wildlife and humans through fish consumption. Yet fish Hg concentrations are highly variable, and key factors driving this variability remain unclear. One little studied source of variation is the influence of habitat-specific feeding on Hg accumulation in lake fish. However, this is likely important because most lake fish feed in multiple habitats during their lives, and the Hg and caloric content of prey from different habitats can differ. This study used a three-pronged approach to investigate the extent to which habitat-specific prey determine differences in Hg bioaccumulation in fish. This study first compared Hg concentrations in common nearshore benthic invertebrates and pelagic zooplankton across five lakes and over the summer season in one lake, and found that pelagic zooplankton generally had higher Hg concentrations than most benthic taxa across lakes, and over a season in one lake. Second, using a bioenergetics model, the effects of prey caloric content from habitat-specific diets on fish growth and Hg accumulation were calculated. This model predicted that the consumption of benthic prey results in lower fish Hg concentrations due to higher prey caloric content and growth dilution (high weight gain relative to Hg from food), in addition to lower prey Hg levels. Third, using data from the literature, links between fish Hg content and the degree of benthivory, were examined, and showed that benthivory was associated with reduced Hg concentrations in lake fish. Taken together, these findings support the hypothesis that higher Hg content and lower caloric content make pelagic zooplankton prey greater sources of Hg for fish than nearshore benthic prey in lakes. Hence, habitat-specific foraging is likely to be a strong driver of variation in Hg levels within and between fish species.

  12. Sport-caught fish consumption and conception delay in licensed Michigan anglers

    SciTech Connect

    Courval, J.M.; DeHoog, J.V.; Stein, A.D.; Tay, E.M.; He, J.; Paneth, N.; Humphrey, H.E.B.

    1999-02-01

    Between 1993 and 1995, the authors surveyed 4,931 licensed anglers aged 17--34 years residing in 10 Michigan counties bordering a Great Lake. Responses were received from 1,443 anglers and 844 of their partners. Lifetime sport-caught fish consumption was estimated as the number of sport-caught fish meals consumed in the previous 12 months times years since 1970 in which sport-caught fish were consumed. Analysis was restricted to currently married couples. Conception delay was reported by 13% of both men and women. Among men, the unadjusted odds ratios (OR) for conception delay were 1.2, 1.3, and 2.0 across the three increasing levels of sport-caught fish consumption compared to none (trend test P = 0.06). After adjustment for age, race, region of Michigan, household income, educational attainment, smoking, alcohol consumption, and partner`s sport fish consumption, the OR for conception delay in men were 1.4, 1.8, and 2.8, respectively. In women, unadjusted OR for conception delay were 0.9, 1.0, and 1.4 with increasing sport-caught fish consumption (trend test P = 0.35). With the same covariates and the sport-caught fish consumption of the woman`s partner included in the model, the OR were 0.8, 0.8, and 1.0, respectively. These data suggest a modest association, in men only, of sport-caught fish consumption with risk of conception delay.

  13. Mercury concentrations in fish from forest harvesting and fire-impacted Canadian Boreal lakes compared using stable isotopes of nitrogen.

    PubMed

    Garcia, Edenise; Carignan, Richard

    2005-03-01

    Total mercury (Hg) concentration was determined in several piscivorous and nonpiscivorous species of fish from 38 drainage lakes with clear-cut, burnt, or undisturbed catchments located in the Canadian Boreal Shield. Mercury concentrations increased with increasing fish trophic position as estimated using stable isotopes of nitrogen (N; r2 = 0.52, 0.49, and 0.30 for cut, reference, and burnt lakes, respectively; p < 0.01). Mercury biomagnification per thousand delta15N varied from 22 to 29% in the three groups of lakes. Mercury availability to organisms at the base of the food chain in lakes with cut catchments was higher than that in reference lakes. In cut lakes, Hg concentrations in fish were significantly related to ratio of the clear-cut area to lake area (or lake volume; r = +0.82 and +0.74, respectively, p < 0.01). Both impact ratios were, in turn, significantly correlated with dissolved organic carbon. These findings suggest that differential loading of organic matter-bound Hg to lakes can affect Hg cycling. In addition, Hg concentrations exceeded the advisory limit for human consumption (0.5 microg/g wet wt) from the World Health Organization in all top predatory species (northern pike, walleye, and burbot) found in cut and in two partially burnt lakes. Thus, high Hg concentrations in fish from forest-harvested and partially burnt lakes may reflect increased exposure to Hg relative to that in lakes not having these watershed disturbances.

  14. Fish consumption and cardiovascular response during mental stress

    PubMed Central

    2012-01-01

    Background Frequent fish consumption is related to a lower risk of coronary heart disease. However, the physiological mechanisms underlying this cardioprotective effect are as yet unknown. We therefore examined certain cardiovascular physiological variables of fish eaters during rest, whilst conducting mental arithmetic, and during recovery. Findings The participants were 12 fish eaters (eating baked fish more than 3–4 times/week) and 13 controls (eating fish less than 1–2 times/week). Analysis of the collected data revealed that heart rate, blood pressure, and pulse wave velocity were significantly lower and pre-ejection period and baroreflex sensitivity were significantly higher in the fish eaters than in the controls during both rest and mental arithmetic, and that systolic and mean blood pressure recovery from mental arithmetic were faster in the fish eaters than in the controls. Conclusions These findings suggest a possible physiological mechanism that may explain why frequent fish consumption reduces coronary heart disease risk. PMID:22695000

  15. 2010 Great Lakes Human Health Fish Tissue Study Fish Tissue Data Dictionary

    EPA Pesticide Factsheets

    The Office of Science and Technology (OST) is providing the fish tissue results from the 2010 Great Lakes Human Health Fish Tissue Study (GLHHFTS). This document includes the “data dictionary” for Mercury, PFC, PBDE and PCBs.

  16. Mysid and fish zooplanktivory in Lake Ontario: quantification of direct and indirect effects

    USGS Publications Warehouse

    Gal, Gideon; Rudstam, Lars G.; Mills, Edward L.; Lantry, Jana R.; Johannsson, Ora E.; Greene, C.

    2011-01-01

    Mysis relicta and planktivorous fish feed on zooplankton in Lake Ontario and form a trophic triangle that includes intraguild predation by fish on mysids. Thus, fish affect zooplankton both directly and indirectly. To evaluate the importance of alewife (Alosa pseudoharengus), rainbow smelt (Osmerus mordax), and mysids as zooplanktivores in Lake Ontario, we measured abundances and distributions, assessed diets, and computed mysid and fish consumption rates based on bioenergetics models. We further estimated indirect effects by comparing clearance rates given observed and potential mysid distributions. Estimated consumption rates varied widely with season and water depth and ranged between 2.6 x 10-3 and 1.3 gm-2day-1 for mysids and between 1.4 x 10-3 and 0.5 gm-2day-1 for fish, representing a daily removal of zooplankton of up to 10.2%-day-1 and 2.0%-day-1 by mysids and fish, respectively. Mysid planktivory exceeded fish planktivory in May and August, but fish planktivory dominated in October. Estimated mysid planktivory rates were 2- to 90-fold lower than the potential rate if mysids moved to temperatures that maximized their predation rates, suggesting an indirect positive effect of fish on zooplankton.

  17. Fish community change in Lake Superior, 1970-2000

    USGS Publications Warehouse

    Bronte, Charles R.; Ebener, Mark P.; Schreiner, Donald R.; DeVault, David S.; Petzold, Michael M.; Jensen, Douglas A.; Richards, Carl; Lozano, Steven J.

    2003-01-01

    Changes in Lake Superior's fish community are reviewed from 1970 to 2000. Lake trout (Salvelinus namaycush) and lake whitefish (Coregonus clupeaformis) stocks have increased substantially and may be approaching ancestral states. Lake herring (Coregonus artedi) have also recovered, but under sporadic recruitment. Contaminant levels have declined and are in equilibrium with inputs, but toxaphene levels are higher than in all other Great Lakes. Sea lamprey (Petromyzon marinus) control, harvest limits, and stocking fostered recoveries of lake trout and allowed establishment of small nonnative salmonine populations. Natural reproduction supports most salmonine populations, therefore further stocking is not required. Nonnative salmonines will likely remain minor components of the fish community. Forage biomass has shifted from exotic rainbow smelt (Osmerus mordax) to native species, and high predation may prevent their recovery. Introductions of exotics have increased and threaten the recovering fish community. Agencies have little influence on the abundance of forage fish or the major predator, siscowet lake trout, and must now focus on habitat protection and enhancement in nearshore areas and prevent additional species introductions to further restoration. Persistence of Lake Superior's native deepwater species is in contrast to other Great Lakes where restoration will be difficult in the absence of these ecologically important fishes.

  18. Selenium-mercury relationships in Idaho lake fish versus Northeastern USA lake fish

    EPA Science Inventory

    Methyl-mercury (MeHg) exposure to wildlife and humans occurs primarily through the foodweb, notably fish consumption. Selenium moderates the toxicity of MeHg in all animal models that utilize selenoenzymatic protein synthesis, as do humans. A Se:Hg molar ratio of <1:1 appears to...

  19. Fish consumption: recommendations versus advisories, can they be reconciled?

    PubMed

    Smith, Kimberly M; Sahyoun, Nadine R

    2005-02-01

    Consumption of at least two servings of fish per week is recommended by the American Heart Association (AHA) to achieve cardio-protective effects. However, some fish are contaminated with methylmercury, which may counteract the positive effect of the omega-3 fatty acids, and numerous governments have issued advisories for certain fish species. These mixed messages may be a source of confusion to the consumer and to the health professional. This paper reviews whether it is possible to follow the AHA recommendation for fish consumption while avoiding the risks associated with consuming mercury in amounts in excess of government thresholds.

  20. A quantitative analysis of fish consumption and stroke risk.

    PubMed

    Bouzan, Colleen; Cohen, Joshua T; Connor, William E; Kris-Etherton, Penny M; Gray, George M; König, Ariane; Lawrence, Robert S; Savitz, David A; Teutsch, Steven M

    2005-11-01

    Although a rich source of n-3 polyunsaturated fatty acids (PUFAs) that may confer multiple health benefits, some fish contain methyl mercury (MeHg), which may harm the developing fetus. U.S. government recommendations for women of childbearing age are to modify consumption of high-MeHg fish to reduce MeHg exposure, while recommendations encourage fish consumption among the general population because of the nutritional benefits. The Harvard Center for Risk Analysis convened an expert panel (see acknowledgements) to quantify the net impact of resulting hypothetical changes in fish consumption across the population. This paper estimates the impact of fish consumption on stroke risk. Other papers quantify coronary heart disease mortality risk and the impacts of both prenatal MeHg exposure and maternal intake of n-3 PUFAs on cognitive development. This analysis identified articles in a recent qualitative literature review that are appropriate for the development of a dose-response relationship between fish consumption and stroke risk. Studies had to satisfy quality criteria, quantify fish intake, and report the precision of the relative risk estimates. The analysis combined the relative risk results, weighting each proportionately to its precision. Six studies were identified as appropriate for inclusion in this analysis, including five prospective cohort studies and one case-control study (total of 24 exposure groups). Our analysis indicates that any fish consumption confers substantial relative risk reduction compared to no fish consumption (12% for the linear model), with the possibility that additional consumption confers incremental benefits (central estimate of 2.0% per serving per week).

  1. Metals in fish from the Upper Benue River and lakes Geriyo and Njuwa in northeastern Nigeria

    SciTech Connect

    Eromosele, C.O.; Eromosele, I.C.; Muktar, S.L.M.; Birdling, S.A.

    1995-01-01

    Lakes Geriyo and Njuwa occupy natural depressions near the upper Benue River in northeastern Nigeria. The lakes are flooded by the river during the rainy season spanning the months of May to September. Fishing activities on the lakes and river provide fish for consumption by the local communities. Industrial activity around the upper Benue River and the lakes is low and there is no information on other activities with the potential for polluting the Benue River as it flows from neighboring Cameroon. However, an unconfirmed report indicated high levels of lead in the upper Benue River, generally speculated as arising from biogeometrical factors. Trace elements, some of which are toxic, may accumulate in edible marine organisms to levels which may be deleterious to human health. For the upper Benue River and its associate lakes, Geriyo and Njuwa, there is yet no report of a systematic study to assess the levels of metals in fish found in these waters. This paper presents the results of a study on metal levels in fish collected from Lakes Geriyo and Njuwa and upper Benue River in northeastern Nigeria. 7 refs., 1 fig., 2 tabs.

  2. Waterbird predation on fish in western Lake Erie: a bioenergetics model application

    USGS Publications Warehouse

    Madenjian, Charles P.; Gabrey, Steven W.

    1995-01-01

    To better understand the role of piscivorous waterbirds in the food web of western Lake Erie, we applied a bioenergetics model to determine their total fish consumption, The important nesting species included the Herring Gull (Larus argentatus), Ring-billed Gull (L. delawarensis), Double-crested Cormorant (Phalacrocorax auritus), Great Blue Heron (Ardea herodias), Black-crowned Night-Heron (Nycticorax nycticorax), and Great Egret (Casmerodius albus). The impact of migrant waterbirds, including the Red-breasted Merganser (Mergus serrator), on western Lake Erie fish biomass was also considered in the analysis. According to the modeling results, during the early 1990s, piscivorous waterbirds consumed 13,368 tonnes of fish from western Lake Erie each year. This tonnage was equivalent to 15.2% of the prey fish biomass needed to support the walleye (Stizostedion vitreum) population in western Lake Erie during a single growing season. The model application was useful in quantifying energy flow between birds and fish in a large lake ecosystem.

  3. Partitioning potential fish yields from the Great Lakes

    USGS Publications Warehouse

    Loftus, D.H.; Olver, C.H.; Brown, Edward H.; Colby, P.J.; Hartman, Wilbur L.; Schupp, D.H.

    1987-01-01

    We proposed and implemented procedures for partitioning future fish yields from the Great Lakes into taxonomic components. These projections are intended as guidelines for Great Lakes resource managers and scientists. Attainment of projected yields depends on restoration of stable fish communities containing some large piscivores that will use prey efficiently, continuation of control of the sea lamprey (Petromyzon marinus), and restoration of high-quality fish habitat. Because Great Lakes fish communities were harmonic before their collapse, we used their historic yield properties as part of the basis for projecting potential yields of rehabilitated communities. This use is qualified, however, because of possible inaccuracies in the wholly commercial yield data, the presence now of greatly expanded sport fisheries that affect yield composition and magnitude, and some possibly irreversible changes since the 1950s in the various fish communities themselves. We predict that total yields from Lakes Superior, Huron, and Ontario will be increased through rehabilitation, while those from Lakes Michigan and Erie will decline. Salmonines and coregonines will dominate future yields from the upper lakes. The Lake Erie fishery will continue to yield mostly rainbow smelt (Osmerus mordax), but the relative importance of percids, especially of walleye (Stizostedion vitreum vitreum) will increase. In Lake Ontario, yields of salmonines will be increased. Managers will have to apply the most rigorous management strictures to major predator species.

  4. Fish losses to double-crested cormorant predation in Eastern Lake Ontario, 1992-97

    USGS Publications Warehouse

    Ross, Robert M.; Johnson, James H.

    1999-01-01

    We examined 4,848 regurgitated digestive pellets of double-crested cormorants (Phalacrocorax auritus) over a 6-year period (1992–97) to estimate annual predation on sport and other fishes in the eastern basin of Lake Ontario. We found more than 51,000 fish of 28 species. Using a model that incorporates annual colony nest counts; fledgling production rates; adult, immature, and young-of-year residence times (seasonal); estimates of mean number of fish per pellet and mean fish size; and a fecal pathway correction factor (4.0 percent), we estimate total annual number of fish consumed by cormorants in the eastern basin of Lake Ontario to range from 37 million to 128 million fish for 1993–97. This fish loss equates to an estimated 0.93 million to 3.21 million kg (mean 2.07 million kg) of fish consumed per year, principally alewife (Alosa pseudoharengus, 42.3 percent) and yellow perch (Perca flavescens, 18.4 percent). Forage fish (alewife, cyprinids, trout-perch [Percopsis omiscomaycus], and other minor components) accounted for 65 percent of the diet, and panfish contributed 34 percent of the diet for the 5-year period. Game fish were minor components of the diet, in view of an average estimated annual consumption of 900,000 smallmouth bass (Micropterus dolomieui, 1.1 percent) and 168,000 salmonines (mostly lake trout, Salvelinus namaycush, 0.2 percent). Cormorant predation on lake trout fingerlings stocked in May 1993 and June 1994 was estimated through the use of coded wire tag recoveries from pellets collected on Little Galloo Island 1 and 4 days after stocking events. We estimated losses of 13.6 percent and 8.8 percent, respectively, of the fish stocked for the two events, an average of 11.2 percent. Such losses may be reduced through alteration of existing stocking practices.

  5. Prey selection by the Lake Superior fish community

    USGS Publications Warehouse

    Isaac, Edmund J.; Hrabik, Thomas R.; Stockwell, Jason D.; Gamble, Allison E.

    2012-01-01

    Mysis diluviana is an important prey item to the Lake Superior fish community as found through a recent diet study. We further evaluated this by relating the quantity of prey found in fish diets to the quantity of prey available to fish, providing insight into feeding behavior and prey preferences. We describe the seasonal prey selection of major fish species collected across 18 stations in Lake Superior in spring, summer, and fall of 2005. Of the major nearshore fish species, bloater (Coregonus hoyi), rainbow smelt (Osmerus mordax), and lake whitefish (Coregonus clupeaformis) consumed Mysis, and strongly selected Mysis over other prey items each season. However, lake whitefish also selected Bythotrephes in the fall when Bythotrephes were numerous. Cisco (Coregonus artedi), a major nearshore and offshore species, fed largely on calanoid copepods, and selected calanoid copepods (spring) and Bythotrephes (summer and fall). Cisco also targeted prey similarly across bathymetric depths. Other major offshore fish species such as kiyi (Coregonus kiyi) and deepwater sculpin (Myoxocephalus thompsoni) fed largely on Mysis, with kiyi targeting Mysis exclusively while deepwater sculpin did not prefer any single prey organism. The major offshore predator siscowet lake trout (Salvelinus namaycush siscowet) consumed deepwater sculpin and coregonines, but selected deepwater sculpin and Mysis each season, with juveniles having a higher selection for Mysis than adults. Our results suggest that Mysis is not only a commonly consumed prey item, but a highly preferred prey item for pelagic, benthic, and piscivorous fishes in nearshore and offshore waters of Lake Superior.

  6. Perceptions about mercury and lead in fish consumed in Lake Albert fishing communities Uganda

    PubMed Central

    Andrew, Tamale; Francis, Ejobi; Charles, Muyanja; Naigaga, Irene; Jesca, Nakavuma; Micheal, Ocaido; Anne, Katuhoire; Deborah, Amulen

    2016-01-01

    Abstract Fish consumption is a lifestyle in fishing communities influenced by individual and communal perceptions. However, information about individual perceptions about fish consumption in the vulnerable fishing community in a developing country is lacking. Without this study, the benefits of fish consumption in a vulnerable community may not be realized. Data collection was executed using key informant interviews and survey structured questionnaires. The key informants include fisheries, community development, veterinary, community and environmental officers. The household heads were the respondents. The Qualitative data was organized and queried using QSR Nvivo 10 and quantitative data analyzed with SPSS version 22. The perceived benefits of eating fish are health, income, nutrition and manhood. The perceived risks are Stigma and ill health. The factors increasing fish consumption are heedless of fish consumption benefits (p = 0.041) and household size i.e. number of adults more than seven (p = 0.020). Those decreasing are methods of preparation of fish i.e. boiling and frying (p = 0.019 and p = 0.010) and oblivious about organizations dealing with fishing activities (p = 0.029). An awareness campaign is needed to demystify the health benefits and fallacies of fish consumption. The knowledge on individual perceptions associated with fish consumption will increase fish consumption but with fewer risks. PMID:27722182

  7. Tagging experiments with lake trout, whitefish, and other species of fish from Lake Michigan

    USGS Publications Warehouse

    Smith, Oliver H.; Van Oosten, John

    1940-01-01

    A total of 2,902 Lake Michigan fish was tagged and released, 48.8 per cent of which were lake trout and 85 per cent lake trout, lake herring, and whitefish. A total of 388 fish or 13.4 per cent was recaptured. The percentages of returns indicated a tremendous fishing intensity for lake trout, whitefish, and sturgeon. About 81 per cent of the recaptured fish were retaken within a radius of 25 miles from the port of tagging (Port Washington, Wisconsin). Lake trout, rainbow trout, and sturgeon were found to be extensive travelers; lake herring, whitefish, chubs, pilots, and perhaps perch did not migrate so extensively. Lake trout, herring, and whitefish tended to move in a northerly direction, perch in a southerly, and rainbow trout in all easterly, toward the Michigan shore. Sturgeon apparently roam all over the lake. Fifty-three per cent of the recovered lake trout were recaptured within one year of release, 73 per cent within 25 miles from Port Washington. It required three years for the trout to become fairly well scattered throughout the lake. With the attainment of adulthood lake trout moved in all directions from the port of release, although nearly 50 per cent of the adults were retaken within 25 miles from this port. Fish moved across state boundaries. Data are given on the growth and estimated age of the tagged lake trout, rainbow trout, whitefish, and sturgeon. The minimum size limits of lake trout and whitefish on the Great Lakes are economically unsound–they are too low–because they permit the capture of these species at a time of most rapid increase in weight.

  8. Acute Renal Failure after Consumption of Fish Gall Bladder

    PubMed Central

    Yu Yao, Bian

    2014-01-01

    A case of acute renal failure after consumption of fish gall bladder as traditional medical remedy is reported. The patient fully recovered with conservative treatment. The risk of acute kidney failure and even multiple organ dysfunction syndrome following ingestion of fish gall bladder is highlighted. PMID:24829840

  9. Issues of Fish Consumption for Cardiovascular Disease Risk Reduction

    PubMed Central

    Raatz, Susan K.; Silverstein, Jeffrey T.; Jahns, Lisa; Picklo, Matthew J.

    2013-01-01

    Increasing fish consumption is recommended for intake of omega-3 (n-3) fatty acids and to confer benefits for the risk reduction of cardiovascular disease (CVD). Most Americans are not achieving intake levels that comply with current recommendations. It is the goal of this review to provide an overview of the issues affecting this shortfall of intake. Herein we describe the relationship between fish intake and CVD risk reduction as well as the other nutritional contributions of fish to the diet. Currently recommended intake levels are described and estimates of fish consumption at a food disappearance and individual level are reported. Risk and benefit factors influencing the choice to consume fish are outlined. The multiple factors influencing fish availability from global capture and aquaculture are described as are other pertinent issues of fish nutrition, production, sustainability, and consumption patterns. This review highlights some of the work that needs to be carried out to meet the demand for fish and to positively affect intake levels to meet fish intake recommendations for CVD risk reduction. PMID:23538940

  10. MERCURY IN SEDIMENT AND FISH FROM NORTH MISSISSIPPI LAKES.

    EPA Science Inventory

    Sediments and/or fish were collected from Sardis, Enid and Grenada Lakes, which are located in three different watersheds in North Mississippi, in order to assess mercury contamination. The mean total mercury concentration in sediments from Enid Lake in 1997 was 0.154 mg Hg/kg, w...

  11. FORAGE FISH AND ZOOPLANKTON COMMUNITY COMPOSITION IN WESTERN LAKE SUPERIOR

    EPA Science Inventory

    We assessed the abundance, size, and species composition of the fish and zooplankton communities of western Lake Superior during 1996 and 1997. Data were analyzed for 3 ecoregions (Duluth-Superior (1), Apostle Islands (2), Minnesota coast (3) differing in lake bathymetry, phsiodo...

  12. Ecology of the Lake Huron fish community, 1970-1999

    USGS Publications Warehouse

    Dobiesz, Norine E.; McLeish, David A.; Eshenroder, Randy L.; Bence, James R.; Mohr, Lloyd C.; Ebener, Mark P.; Nalepa, Thomas F.; Woldt, Aaron P.; Johnson, James E.; Argyle, Ray L.; Makarewicz, Joseph C.

    2005-01-01

    We review the status of the Lake Huron fish community between 1970 and 1999 and explore the effects of key stressors. Offshore waters changed little in terms of nutrient enrichment, while phosphorus levels declined in inner Saginaw Bay. Introduced mussels (Dreissena spp.) proliferated and may have caused a decline in Diporeia spp. This introduction could have caused a decline in lake whitefish (Coregonus clupeaformis) growth and condition, with serious repercussions for commercial fisheries. Bythotrephes, an exotic predatory cladoceran, and other new exotics may be influencing the fish community. Sea lampreys (Petromyzon marinus) remained prevalent, but intensive control efforts on the St. Mary's River may reduce their predation on salmonines. Overfishing was less of a problem than in the past, although fishing continued to reduce the amount of lake trout (Salvelinus namaycush) spawning biomass resulting from hatchery-reared fish planted to rehabilitate this species. Massive stocking programs have increased the abundance of top predators, but lake trout were rehabilitated in only one area. Successful lake trout rehabilitation may require lower densities of introduced pelagic prey fish than were seen in the 1990s, along with continued stocking of hatchery-reared lake trout and control of sea lamprey. Such reductions in prey fish could limit Pacific salmon (Oncorhynchus spp.) fisheries.

  13. Annotated list of the fishes of the Lake Ontario watershed

    USGS Publications Warehouse

    Crossman, Edwin J.; Van Meter, Harry D.

    1979-01-01

    This annotated list of the fishes of Lake Ontario and its watershed is based on published distribution records, museum collections, and reports of fish surveys that confirm the occurrence of fish species dating back to the 1850's. It includes 130 forms (129 spp. + the hybrid splake), 20 of which have disappeared or are extremely rare today. Considering species present only in the lake proper, 64 were reported in 1929, and 51 of those remained in 1972-73 (13 having disappeared). Seventeen species and the splake are fishes not known to have occurred in the lake in 1929 or were introduced since then. A list of 86 references pertinent to the study of the fish fauna of the watershed is given. The present list, started in 1972, includes some information from as late as 1976.

  14. Body burden levels of dioxin, furans, and PCBs among frequent consumers of Great Lakes sport fish

    SciTech Connect

    Falk, C.; Hanrahan, L.; Anderson, H.A.; Draheim, L.; Kanarek, M.S.; Needham, L.; Patterson, D. Jr.

    1999-02-01

    Dioxins, furans, and polychlorinated biphenyls (PCBs) are toxic, persist in the environment, and bioaccumulate to concentrations that can be harmful to humans. The Health Departments of five GL states, Wisconsin, Michigan, Ohio, Illinois, and Indiana, formed a consortium to study body burden levels of chemical residues in fish consumers of Lakes Michigan, Huron, and Erie. In Fall 1993, a telephone survey was administered to sport angler households to obtain fish consumption habits and demographics. A blood sample was obtained from a portion of the study subjects. One hundred serum samples were analyzed for 8 dioxin, 10 furan, and 4 coplanar PCB congeners. Multiple linear regression was conducted to assess the predictability of the following covariates: GL sport fish species, age, BMI, gender, years sport fish consumed, and lake. Median total dioxin toxic equivalents (TEq), total furan TEq, and total coplanar PCB TEq were higher among all men than all women (P = 0.0001). Lake trout, salmon, age, BMI, and gender were significant regression predictors of log (total coplanar PCBs). Lake trout, age, gender, and lake were significant regression predictors of log (total furans). Age was the only significant predictor of total dioxin levels.

  15. Depth as an organizer of fish assemblages in floodplain lakes

    USGS Publications Warehouse

    Miranda, L.E.

    2011-01-01

    Depth reduction is a natural process in floodplain lakes, but in many basins has been accelerated by anthropogenic disturbances. A diverse set of 42 floodplain lakes in the Yazoo River Basin (Mississippi, USA) was examined to test the hypothesis of whether depth reduction was a key determinant of water quality and fish assemblage structure. Single and multiple variable analyses were applied to 10 commonly monitored water variables and 54 fish species. Results showed strong associations between depth and water characteristics, and between depth and fish assemblages. Deep lakes provided less variable environments, clearer water, and a wider range of microhabitats than shallow lakes. The greater environmental stability was reflected by the dominant species in the assemblages, which included a broader representation of large-body species, species less tolerant of extreme water quality, and more predators. Stability in deep lakes was further reflected by reduced among-lake variability in taxa representation. Fish assemblages in shallow lakes were more variable than deep lakes, and commonly dominated by opportunistic species that have early maturity, extended breeding seasons, small adult size, and short lifespan. Depth is a causal factor that drives many physical and chemical variables that contribute to organizing fish assemblages in floodplain lakes. Thus, correlations between fish and water transparency, temperature, oxygen, trophic state, habitat structure, and other environmental descriptors may ultimately be totally or partly regulated by depth. In basins undergoing rapid anthropogenic modifications, local changes forced by depth reductions may be expected to eliminate species available from the regional pool and could have considerable ecological implications. ?? 2010 Springer Basel AG (outside the USA).

  16. 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.

  17. 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.

  18. Fish consumption, fish atopy and related heavy metals in childhood eczema.

    PubMed

    Hon, Kam Lun; Lui, Heike; Wang, Shuxin Susan; Lam, Hugh Simon; Leung, Ting Fan

    2012-09-01

    Due to increasing worldwide water pollution, fish might be a source of excessive zinc, mercury, arsenic or manganese intake. The aim of this study was to evaluate if fish atopy/sensitization and fish consumption behavior are associated with eczema severity and blood levels of the 4 heavy metals.One-hundred and nineteen patients with eczema and 43 patients with miscellaneous non-eczema skin diseases were studied. There were no differences in average weekly fish consumption and blood levels of the 4 heavy metals between eczema and non-eczema groups. Blood levels of these metals were generally within the upper limits of local reference ranges in all these patients. In eczema patients, freshwater fish consumption behavior in days-per-week was correlated with blood arsenic and mercury levels (rho=0.17, p<0.01 for both metals), but not with zinc or manganese. Levels of arsenic and mercury were also correlated with days of seawater fish consumption per week (arsenic: 0.38, mercury: 0.24, p <0.05).Fish sensitization was present in 25% of patients with eczema. Nevertheless, there was no difference in terms of fish consumption behavior, eczema severity, quality of life, and heavy metal levels between eczema patients with or without fish sensitization. We conclude that without exceeding local normal reference ranges, blood arsenic and mercury levels correlated with fish consumption behavior. There is no evidence to suggest that fish sensitization is associated with more severe eczema (bad for eczema), or that patients have milder eczema with more days of fish consumption (good for eczema).

  19. A study on the levels of radioactivity in fish samples from the experimental lakes area in Ontario, Canada.

    PubMed

    Chen, Jing; Rennie, Michael D; Sadi, Baki; Zhang, Weihua; St-Amant, Nadereh

    2016-03-01

    To better understand background radiation levels in country foods, a total of 125 fish samples were collected from three lakes (Lake 226, Lake 302 and Lake 305) in the Experimental Lakes Area (ELA) in Ontario of Canada during the summer of 2014. Concentrations of naturally occurring radionuclides ((226)Ra, (210)Pb and (210)Po) as well as anthropogenic radionuclides ((134)Cs and (137)Cs) were measured. This study confirmed that (210)Po is the dominant contributor to radiation doses resulting from fish consumption. While concentrations of (210)Pb and (226)Ra were below conventional detection limits, (210)Po was measured in almost all fish samples collected from the ELA. The average concentration was about 1.5 Bq/kg fresh weight (fw). None of the fish samples analysed in this study contained any detectable levels of (134)Cs. An average (137)Cs level of 6.1 Bq/kg fw was observed in freshwater fishes harvested in the ELA, almost twice that of samples measured in the National Capital Region of Canada in 2014 and more than 20 times higher than the levels observed in marine fish harvested from the Canadian west coast in 2013 and 2014. However, it is important to note that the concentrations of (137)Cs in fish samples from these inland lakes are considered very low from a radiological protection perspective. The resulting radiation dose for people from fish consumption would be a very small fraction of the annual dose from exposure to natural background radiation in Canada. The results indicate that fishes from inland lakes do not pose a radiological health concern.

  20. Total organochlorine content of fish from the Great Lakes

    SciTech Connect

    Newsome, W.H.; Andrews, P.; Conacher, H.B.; Rao, R.R.; Chatt, A. )

    1993-07-01

    Residues of polychlorinated biphenyls (PCBs) and organochlorine pesticides were determined in several species of commercial fish from the Great Lakes and compared to the total organic chlorine determined by neutron activation analysis. The mean organochlorine contents ranged from 44 to 138 ppm (lipid basis) and were 5 to 72 times higher than the contents of PCBs and organochlorine pesticides. Marine fish also contained a large proportion of unidentified organic chlorine. The unknown material in the Great Lakes fish was found to chromatograph with the high molecular weight lipid fraction by gel permeation chromatography.

  1. Fish consumption and advisory awareness among expectant women.

    PubMed

    Gliori, Gemma; Imm, Pam; Anderson, Henry A; Knobeloch, Lynda

    2006-03-01

    During the spring of 2003, the Wisconsin Department of Health and Family Services (DHFS) piloted a fish consumption advisory program targeted at pregnant women. Fish consumption recommendations and information about the prenatal effects of methylmercury were illustrated in multilingual posters, brochures, fact cards, and other promotional items. These materials were mailed to Women, Infants and Children (WIC) program providers, local health departments, and medical clinics, along with a cover letter that encouraged them to display the materials in waiting areas and distribute them to new mothers and expectant women who visited their facilities. In August 2003, a survey was mailed to 1000 women who had given birth during the first week of June 2003. The survey was intended to provide an estimate of the number and types of fish meals the women had consumed during pregnancy and evaluate their familiarity with the outreach materials. On average, survey respondents consumed 3 fish meals a month. The most frequently consumed fish were canned tuna and frozen fish. Approximately one third of women knew that older fish and predatory fish have the highest levels of mercury. While almost half of the women were aware of Wisconsin's sport fish advisory, only 13% of them remembered seeing any of the outreach materials.

  2. Lake Michigan fish acoustic data from 2011 to 2016

    USGS Publications Warehouse

    Warner, David M.; Claramunt, Randall M.; Hanson, Dale

    2016-01-01

    Each line in the file “Lake Michigan fish acoustic data from 2011 to 2016.csv” represents the acoustic data and estimated fish density for a single depth layer of water. Surveys are conducted along transects, transects are divided horizontally into successive intervals, and then within an interval there are multiple successive depth layers. Area backscattering (ABC), mean acoustic size (sigma), and fish density are reported for each unique transect-interval – layer from Lake Michigan in the years 2011-2016. Area backscattering (PRC_ABC), mean acoustic size (sigma), and fish density in the intervals and layers of acoustic survey transects of Lake Michigan in the years 2011-2016. The survey is carried out using a stratified, systematic design with transect locations randomized within each stratum. As a result, transect location varies each year.

  3. The ecology of Lake Nakuru (Kenya) : V. Production and consumption of consumer organisms.

    PubMed

    Vareschi, E; Jacobs, J

    1984-01-01

    Consumer production and consumption were studied in the equatorial alkaline-saline Lake Nakuru from 1972 to 1976. Together with earlier reports (including a study of the dominant consumer, the Lesser Flamingo Phoeniconaias minor), the data provide the basis for estimating the major pathways of energy flow. Detritus food chains were not included in this project.Production and consumption rates were estimated from the distribution of numbers and size classes in the lake and laboratory experiments on growth and filtration rates. Rotifers (Brachionus dimidiatus and B. plicatilis), though not especially significant in biomass, had the highest production rates (1.7 KJ m(-3) d(-1)) due to a very short juvenile phase (ca. 2 days) and fast production of very large eggs (about 1 per day). Consumption rates were correspondingly high (11.3 KJ m(-3) d(-1)), comparable only to those of the Lesser Flamingo (12.6 KJ m(-3) d(-1); in this species, production was negligible because the birds do not breed at L. Nakuru). Copepods almost matched rotifers in 1972/73 (production 1.5, consumption 6.5 KJ m(-3) d(-1)) but vanished from the lake in the following years. Chironomid larvae (mainly Leptochironomus deribae) and fish (Sarotherodon alcalicus grahami) had similar ranges of production (0.7 and 0.4 KJ m(-3) d(-1)) and consumption (3.6 and 3.4 KJ m(-3) d(-1)) although the fish had about twice the biomass (20 KJ m(-3)) of the insects.Most primary consumer organisms fed on the dominant primary producer, the cyanophyte Spirulina platensis, but rotifers and Leptochironomus met an unknown fraction of their energy requirements by consuming bacteria and detritus. Of the secondary consumers only fisheating birds (≈90% adult Pelecanus onocrotalus) and the Greater Flamingo (Phoenicopterus ruber, mainly full-grown individuals) contributed significantly to the energy flow. Neither pelicans nor Greater Flamingos breed at L. Nakuru, therefore their production rates were negligible. The total fish

  4. The risk of mercury exposure to the people consuming fish from Lake Phewa, Nepal.

    PubMed

    Thapa, Devna Singh; Sharma, Chhatra Mani; Kang, Shichang; Sillanpää, Mika

    2014-06-27

    The risk of mercury exposure through consumption of fish from Lake Phewa, Nepal was investigated. A total of 170 people were surveyed to know their fish consumption levels. The weekly mercury (Hg) intake in the form of methylmercury (MeHg) through fish was calculated by using the data on average MeHg concentrations in fish, the average consumption of fish per week, and an average body weight of the people. Hotel owners were consuming significantly high amounts of fish, followed by fishermen, in comparison to the government staff, army/police, locals and others (visitors). Some individuals exceeded the Provisional Tolerable Weekly Intake (PTWI) of 1.6 µg per kg body weight of MeHg (FAO/WHO). The minimum intake of MeHg (0.05 µg/kg/week) was found in the visitors (others) category, whereas the hotel owners had the maximum intake (3.71 µg/kg/week). In general, it was found that a person of 60 kg can consume at least 2 kg of fish per week without exceeding PTWI such that it does not pose any health risk associated with Hg poisoning at the present contamination level. Hg based PTWI values for Nepal has not been proposed yet in fishery resources so as to reduce health risk of the people.

  5. [The consumption of dishes and/or fishy snacks by school youth from Miedzychodzko-Sierakowskie lakes].

    PubMed

    Bortnowska, Grazyna; Grotowska, Longina; Goluch-Koniuszy, Zuzanna

    2011-01-01

    The school youth inhabiting Miedzychodzko-Sierakowskie lakes consumed dishes and/or fishy snacks on the similar low level as their peers in other regions of country, mainly breaded fried fishes and partly or highly manufactured products i.e., herrings in sour cream as well as pastes from smoked fishes and canned fishes. Relatively high ranks in rows of preference (liking) and frequency intake were found for carp, herring and cheap cultured panga from import. The presence of bones and specific odour were the factors that mostly affected low consumption of dishes and/or snacks from fishes. It seems that preparation of attractive tasty dishes and/or snacks from fresh fishes could help in youth teaching regarding correct nutritional habits as well as retain tradition of their consumption during adult life.

  6. Responses of Ambystoma gracile to the removal of introduced nonnative fish from a mountain lake

    USGS Publications Warehouse

    Hoffman, Robert L.; Larson, Gary L.; Samora, B.

    2004-01-01

    Introduced, nonnative brook trout (Salvelinus fontinalis) were removed from a mountain lake in Mount Rainier National Park, Washington, to examine the capacity of native Ambystoma gracile (Northwestern Salamander) in the lake to respond to the intentional removal of fish. Temporal trends (N) were calculated for A. gracile larvae/neotene and egg mass relative abundances in the Fish Removal and an adjacent Fishless Lake. The diel and spatial patterns of A. gracile in the lakes were also enumerated during time-intervals of fish presence in and after fish removal from the Fish Removal Lake. Sixty-six fish were removed from the Fish Removal Lake. The Ns for relative abundances in the Fish Removal Lake were positive for the study period and indicated that the number of larvae/neotenes and egg masses observed in the lake increased concurrent with the removal and extirpation of fish from the lake. Numbers of larvae/neotenes and egg masses observed in the Fishless Lake varied annually, but no overall positive or negative trends were evident during the study. Ambystoma gracile in the Fish Removal Lake, during fish presence, were predominantly nocturnal and located in the shallow, structurally complex nearshore area of the lake. After fish were removed, the number of A. gracile observed in the lake increased, especially during the day and in the deeper, less structurally complex offshore area of the lake. Fishless Lake A. gracile were readily observed day and night in all areas of the lake throughout the study. The A. gracile in the Fish Removal Lake behaviorally adapted to the presence of introduced fish and were able to recover from the affects of the fish following fish removal. This study underscores the important relationship between species life history and the variability of responses of montane aquatic-breeding amphibians to fish introductions in mountain lakes.

  7. PCB intake from sport fishing along the Northern Illinois shore of Lake Michigan

    SciTech Connect

    Pellettieri, M.B.; Hallenbeck, W.H.; Brenniman, G.R.; Cailas, M.; Clark, M.

    1996-12-31

    Polychlorinated biphenyls (PCBs) are chlorinated hydrocarbons with an empirical formula of C{sub 12}H{sub 10-x}Cl{sub x}. The biphenyl can have from one to 10 chlorine substitutions resulting in 209 theoretical congeners. Commercial formulations of PCBs are complex mixtures of congeners; 125 congeners have been identified in commercial formulations. PCBs have entered the aquatic environment by industrial discharge, airborne deposition, and release from sediments. The most likely route of non-occupational human exposure to PCBs is from consumption of contaminated fish. PCBs are considered to be the most important contaminants in fish from the Great Lakes. Hence, in 1993 the Great Lakes Fish and Advisory Task Force developed a fish consumption advisory for the Great Lakes which incorporated a Health Protection Value (HPV) of 3.5 {mu}g of PCBs/day. This study combines the creel species, weight, and length distribution data with PCB monitoring data to quantitate the theoretical intake of PCBs by sport fishermen in the Chicago area. 6 refs., 3 tabs.

  8. Mercury concentrations in fish from three major lakes in north Mississippi: Spatial and temporal differences and human health risk assessment.

    PubMed

    Wolff, Stacy; Brown, Garry; Chen, Jingjing; Meals, Keith; Thornton, Cammi; Brewer, Steve; Cizdziel, James V; Willett, Kristine L

    2016-01-01

    The goal of this study was to compare total mercury (Hg) concentrations in fish muscle tissue and assess consumption health risks of fish collected from three north Mississippi lakes (Sardis, Enid, and Grenada) that are extensively used for fishing and recreation. Largemouth bass (LMB; n = 64), channel catfish (CC; n = 72), and white crappie (WC; n = 100), which represent a range of trophic levels, were collected during spring 2013 and 2014. Creel data estimated that anglers harvested approximately 370,000 kg of WC, 27,000 kg of CC, and 15,000 kg of LMB from the lakes annually. Median Hg wet weight concentrations were highest in LMB (443 ng/g), followed by CC (211 ng/g) and WC (192 ng/g). Fish-Hg concentrations were lower than those reported in fish >10 years ago. There were significant differences between lakes consistent across species. Grenada length-normalized fish-Hg concentrations were higher than those from Enid and Sardis. Because existing consumption advisories for CC are length based, the lack of relationship between length and Hg concentration indicated that the recommendations may not be sufficiently protective. Further, five different risk assessment paradigms yielded hazard quotient (HQ) values suggesting that existing fish consumption advisories may be insufficient to protect adults and especially children from exposure to Hg.

  9. Development of a Fish Based Lake Typology for Natural Austrian Lakes >50 ha Based on the Reconstructed Historical Fish Communities

    NASA Astrophysics Data System (ADS)

    Gassner, Hubert; Wanzenböck, Josef; Zick, Daniela; Tischler, Gerhard; Pamminger-Lahnsteiner, Barbara

    2005-08-01

    Based on the reconstructed native fish communities all natural Austrian lakes >50 ha (n = 43) were classified into four groups using cluster analysis methods. Sentinel species (i.e. species with highest discriminating value for lake types and characteristic for a specific lake group) and type specific fish species (accompanying species with additional value for characterising lake groups) were defined by a newly developed index and by similarity analysis. The first group included 16 lakes of high altitude, small surface area and low fish species number with arctic char as a sentinel species. The second group (n = 10) was characterized by intermediate altitude, large surface area and high maximum water depth with the minnow as sentinel species. The third group contained 14 lakes with low maximum water depths and a long retention time. For this group the bleak was found as a sentinel species. The lakes of the eastern part of Austria represented the last group (n = 3) and were characterized by low altitude and very shallow water depth with pike-perch as a sentinel species.

  10. Proximate composition and caloric content of eight Lake Michigan fishes

    USGS Publications Warehouse

    Rottiers, Donald V.; Tucker, Robert M.

    1982-01-01

    We measured the proximate composition (percentage lipid, water, fat-free dry material, ash) and caloric content of eight species of Lake Michigan fish: lake trout (Salvelinus namaycush), coho salmon (Oncorhynchus kisutch), lake whitefish (Coregonus clupeaformis), bloater (Coregonus hoyi), alewife (Alosa pseudoharengus), rainbow smelt (Osmerus mordax), deepwater sculpin (Myoxocephalus quadricornis), and slimy sculpin (Cottus cognatus). Except for alewives, proximate composition and caloric content did not differ significantly between males and females. And, for coho salmon, there was no significant difference in composition between fish collected in different years. Lipid and caloric content of lake trout increased directly with age. In all species examined, lipids and caloric contents were significantly lower in small, presumably immature, fish than in larger, older fish. Lipid content of lake trout, lake whitefish, and bloaters (range of means, 16-22%) was nearly 3 times higher than that of coho salmon, sculpins, rainbow smelt, and alewives (range of means, 5.2-7.0%). The mean caloric content ranged from 6.9 to 7.1 kcal/g for species high in lipids and from 5.8 to 6.3 kcal/g for species low in lipids. Although the caloric content of all species varied directly with lipid content and inversely with water content, an increase in lipid content did not always coincide with a proportional increase in caloric content when other components of fish composition were essentially unchanged. This observation suggests that the energy content of fish estimated from the proximate composition by using universal conversion factors may not necessarily be accurate.

  11. Land, lake, and fish: Investigation of fish remains from Gesher Benot Ya'aqov (paleo-Lake Hula).

    PubMed

    Zohar, Irit; Biton, Rebecca

    2011-04-01

    The question of whether or not pre-modern hominins were responsible for the accumulation of fish remains is discussed through analyses of remains recovered from two lacustrine facies (I-4 and I-5) from Area A of the Acheulian site of Gesher Benot Ya'aqov (GBY) in the Jordan Rift Valley, Israel. The fish remains provide the first glimpse into the naturally accumulated fish assemblage from the fluctuating shores of a lake that had been continually exploited by early hominins some 780,000 years ago. Preliminary analysis of the remains show that thirteen of the seventeen species native to Lake Hula were identified at GBY. These represent three of the five freshwater fish families native to the lake: Cyprinidae (carps), Cichlidae (tilapini, St. Peter's fish), and Clariidae (catfish). From a taphonomical perspective, a significant difference is found between the two lithofacies (Layers I-4 and I-5) in terms of species composition, richness, diversity, and skeleton completeness. It appears that the fish remains recovered from Layer I-4 (clay) are better preserved than those from Layer I-5 (coquina). In both lithofacies, Cyprinidae are highly abundant while Cichlidae and Clariidae are rare and under-represented, especially when compared to the Lake Hula fishery report from the 1950s. All of these identified species may have contributed significantly to the diet of GBY hominins.

  12. Review of fish diversity in the Lake Huron basin

    USGS Publications Warehouse

    Roseman, E.F.; Schaeffer, J.S.; Steen, P.J.

    2009-01-01

    Lake Huron has a rich aquatic habitat diversity that includes shallow embayments, numerous tributaries, shallow mid-lake reef complexes, archipelagos, and profundal regions. These habitats provide support for warm, cool, and cold water fish communities. Diversity of fishes in Lake Huron reflects post-glaciation colonization events, current climate conditions, accidental and intentional introductions of non-indigenous species, and extinctions. Most extinction events have been largely associated with habitat alterations, exploitation of fisheries, and interactions with non-indigenous species. The most recent historical survey of extirpated and imperiled species conducted in the late 1970s identified 79 fish species in Lake Huron proper and about 50 additional species in tributaries. Of those 129 species, 20 are now considered extirpated or imperiled. Extirpated species include Arctic grayling, paddlefish, weed shiner, deepwater cisco, blackfin cisco, shortnose cisco, and kiyi. Six species have declined appreciably due to loss of clear-water stream habitat: the river redhorse, river darter, black redhorse, pugnose shiner, lake chubsucker, redside dace, eastern sand darter, and channel darter. While numerous agencies, universities, and other organizations routinely monitor nearshore and offshore fish distribution and abundance, there is a need for more rigorous examination of the distribution and abundance of less-common species to better understand their ecology. This information is critical to the development of management plans aimed at ecosystem remediation and restoration.

  13. Concentrations of trace elements in Great Lakes fishes

    USGS Publications Warehouse

    Lucas, Henry F.; Edgington, David N.; Colby, Peter J.

    1970-01-01

    The concentration of 15 trace elements was determined by activation analysis of samples of whole fish and fish livers from three of the Great Lakes: Michigan, Superior, and Erie. The average concentrations of 7 elements in 19 whole fish from 3 species were as follows: uranium, 3 ppb (parts per billion); thorium, 6 ppb; cobalt, 28 ppb; cadmium, 94 ppb; arsenic, 16 ppb; chromium, 1 ppm; and copper, 1.3 ppm. The average concentrations of 8 elements in 40 liver samples from 10 species of fish were as follows: uranium, ~ 2 ppb; thorium, a?? 2 ppb; cobalt, 40 ppb; copper, 9 ppm; zinc, 30 ppm; bromine, 0.4 ppm; arsenic, 30 ppb; and cadmium, 0.4 ppm. Other elements observed in most of the samples were: antimony, 5-100 ppb; gold, 2-5 ppb; lanthanum, 1-20 ppb; rhenium, 0.5-5 ppb; rubidium, 0.06-4 ppm; and selenium, 0.1-2 ppb. Trace element concentrations varied with species and lake. Uranium and thorium varied with species, but not for the same species from different lakes. The levels of copper, cobalt, zinc, and bromine varied little between species and lakes. The concentration of cadmium, arsenic, and chromium varied between species and with species between lakes.

  14. DIEL OXYGEN-INDUCED MOVEMENT OF FISH ASSEMBLAGES IN A GREAT LAKES COASTAL WETLAND

    EPA Science Inventory

    To determine the importance of dissolved oxygen conditions in influencing daily ovement patterns of fishes in Great Lakes coastal wetlands, we sampled migrating fish assemblages from habitats with varying diurnal dissolved oxygen patterns in a Lake Superior coastal wetland during...

  15. DISTRIBUTIONS OF LAKE FISHES OF THE NORTHEAST USA--III. SALMONIDAE AND ASSOCIATED COLDWATER SPECIES

    EPA Science Inventory

    We present distributional maps and discuss native status for fish species characteristic of coldwater lakes, sampled from 203 randomly selected lakes in the northeastern USA (New England, New York, New Jersey). Eleven coldwater fish species from four families (Salmonidae, Osmeri...

  16. Status of coregonine fishes in the Laurentian Great Lakes

    USGS Publications Warehouse

    Fleischer, Guy W.

    1992-01-01

    The post-glacial coregonine assemblage in the Great Lakes included several species of the genera Prosopium and Coregonus. Overfishing, habitat degradation, and competition with various exotic fish species severely reduced coregonine abundance and altered their distribution by the mid to latter part of the 20th century. Most of the original Coregonus species, some which were endemic to the Great Lakes, are now extinct or are extremely rare. The prevailing coregonines are mostly benthic and deep-water species, contrasted to the original assemblage dominated by pelagic, nearshore species. Lake whitefish (Coregonus clupeaformis) populations have recovered and now support record fisheries in Lakes Superior, Michigan, and Huron. Bloaters (C. hoyi) have recovered to dominate the planktivorous fish community in Lake Michigan and are rapidly increasing in Lake Huron. The recent resurgence in some coregonine populations are linked to declines in exotic fish populations and favorable climatic changes. The reduced diversity of the coregonines may explain the dominance of the remaining species. The stability of this simplified coregonine community is uncertain but the existing coregonines have demonstrated resiliency.

  17. Diet niches of major forage fish in Lake Michigan

    USGS Publications Warehouse

    Davis, B.M.; Savino, J.F.; Ogilvie, L.M.; ,

    2007-01-01

    A large complex of coregonine species historically dominated the fish community of Lake Michigan. The current species complex is simplified with one remaining coregonine, bloater (Coregonus hoyi), deepwater sculpin (Myoxocephalus thompsoni), slimy sculpin (Cottus cognatus), and two dominant invaders, alewife (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax). To better understand the diet relationships of the major offshore forage fishes now in Lake Michigan, diets of bloater, alewife, rainbow smelt, deepwater sculpin, and slimy sculpin were compared. The three sites, chosen to represent northern, central, and southern components of the lake, were sampled during spring, summer, and fall in 1994, and spring and fall in 1995. Forage fishes had diverse and variable diets, with niches differentiated by prey type or location. Diporeia hoyi, Mysis relicta, and zooplankton were the major diet items. The index of relative importance showed benthic (slimy and deepwater sculpins) and pelagic (alewife, rainbow smelt) feeding strategies with opportunistic bloaters incorporating both feeding strategies. Highest diet overlaps were between species of sculpin, and between large and small bloaters; both groups partitioned food by size. Though competition for food may be minimized by spatial segregation of potential competitors, the forage fish in Lake Michigan apparently partition food resources. Fishery management models incorporating food habits of pelagic forage fish would need to take into account diet variation associated with location and season. ?? 2007 E. Schweizerbart'sche Verlagsbuchhandlung.

  18. Contaminants in fish tissue from US lakes and reservoirs: A national probabilistic study

    EPA Science Inventory

    An unequal probability design was used to develop national estimates for 268 persistent, bioaccumulative, and toxic chemicals in fish tissue from lakes and reservoirs of the conterminous United States (excluding the Laurentian Great Lakes and Great Salt Lake). Predator (fillet) ...

  19. Mercury in the muscle tissue of fish from three northern Maine lakes

    SciTech Connect

    Akielaszek, J.J.; Haines, T.A.

    1981-08-01

    We report the levels of mercury in the muscle tissue of brook trout (Salvelinus fontinalis) and lake trout (S. namaycush) from three northern Maine lakes. Mercury levels in fish from two wilderness lakes in the same drainage basin were compared with each other, and in turn with those in fish from a lake in a separate drainage basin. The fish species composition in one of the wilderness lakes, Cliff Lake, is different from that in the other two lakes, enabling us to analyze the effects of trophic structure on mercury concentration in top carnivores. It is unlikely that mercury from agricultural, geological, or local industrial sources occurs in these lakes.

  20. Massive fish mortality and Cylindrospermopsis raciborskii bloom in Aleksandrovac Lake.

    PubMed

    Svirčev, Zorica; Obradović, Vesna; Codd, Geoffrey A; Marjanović, Prvoslav; Spoof, Lisa; Drobac, Damjana; Tokodi, Nada; Petković, Anđelka; Nenin, Tanja; Simeunović, Jelica; Važić, Tamara; Meriluoto, Jussi

    2016-09-01

    This paper presents a case study of a massive fish mortality during a Cylindrospermopsis raciborskii bloom in Aleksandrovac Lake, Serbia in mid-December 2012. According to a preliminary investigation of the samples taken on November 6 before the fish mortalities and to extended analyses of samples taken on November 15, no values of significant physicochemical parameters emerged to explain the cause(s) of the fish mortality. No industrial pollutants were apparent at this location, and results excluded the likelihood of bacterial infections. Even after freezing, the dissolved oxygen concentration in the water was sufficient for fish survival. High concentrations of chlorophyll a and phaeophytin occurred in the lake, and phytoplankton bloom samples were lethal in Artemia salina bioassays. A bloom of the cyanobacterium C. raciborskii was recorded during November. Although the A. salina bioassays indicated the presence of toxic compounds in the cyanobacterial cells, the cyanotoxins, microcystins, cylindrospermopsin and saxitoxin were not detected.

  1. Assessment of pollution levels in fish and water of main basin, Lake Mariut.

    PubMed

    Amr, Hanaa M; El-Tawila, Mahmoud M; Ramadan, Mohamed H M

    2005-01-01

    Lake Mariut has suffered over the years from the untreated sewage, agricultural and industrial wastes dumped into it. Lake Mariut fish quality and quantity were adversely affected eventually being unfit for human consumption due to its poor water quality. The present study was carried out to evaluate the levels of metals in the fish caught from Lake Mariut main basin and its fitness for human consumption, and the water quality after the enforcement of the Egyptian Law for Environmental Protection (Law 4/1994). Fish and water samples were collected form Lake Mariut main basin through out the period from May to December 2000. The results showed that mercury was totally undetected in fish and water samples. The levels of Fe obtained were very low compared to previous studies. Fe and Cr contents in fish flesh were higher compared to their levels in water samples. Also Cu has shown a decrease in both fish and water samples. Zn and Cd contents in water samples have decreased compared with former studies. However, they have not changed in fish flesh. Pb content in both fish flesh and water samples has shown a great decrease compared to previous studies. The Cd and Pb mean values in fish flesh of the present study (0.81 and 0.14 mg/kg) exceeded the Egyptian Standards No. 2360/1993 value (should not exceed 0.1 mg/kg for each). The results also showed that the water quality has changed compared with previous studies. BOD has increased in north of Main Basin, east of Main Basin, South of Main Basin, and southwest of Main Basin; and deCreased in WTP effluent; and Qalaa Drain. There has been an increase in TSS, TVSS, and NO3 levels compared to pervious studies. There has been a decrease in TS, TDS, COD,hardness, and chloride levels. This decrease, especially in COD, may be attributed to the enforcement of the Egyptian Law 4/1994. The pH and alkalinity were in agreement with the values shown by previous studies except for east of Main Basin which showed higher values. The study

  2. Radioactive contamination of fishes in lake and streams impacted by the Fukushima nuclear power plant accident.

    PubMed

    Yoshimura, Mayumi; Yokoduka, Tetsuya

    2014-06-01

    The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in March 2011 emitted radioactive substances into the environment, contaminating a wide array of organisms including fishes. We found higher concentrations of radioactive cesium ((137)Cs) in brown trout (Salmo trutta) than in rainbow trout (Oncorhynchus nerka), and (137)Cs concentrations in brown trout were higher in a lake than in a stream. Our analyses indicated that these differences were primarily due to differences in diet, but that habitat also had an effect. Radiocesium concentrations ((137)Cs) in stream charr (Salvelinus leucomaenis) were higher in regions with more concentrated aerial activity and in older fish. These results were also attributed to dietary and habitat differences. Preserving uncontaminated areas by remediating soils and releasing uncontaminated fish would help restore this popular fishing area but would require a significant effort, followed by a waiting period to allow activity concentrations to fall below the threshold limits for consumption.

  3. Species succession and sustainability of the Great Lakes fish community

    USGS Publications Warehouse

    Eshenroder, Randy L.; Burnham-Curtis, Mary K.; Taylor, William W.; Ferreri, C. Paola

    1999-01-01

    This article concentrates on the sustainability of the offshore pelagic and deepwater fish communities that were historically dominated by lake trout (Salvelinus namaycush). The causes of alteration in these fish communities (i.e., overfishing, introductions, and cultural eutrophication) were identified by Loftus and Regier (1972). Here we look at the ecology of these altered communities in relation to sustainability and discuss the need for restoration.

  4. Potential effects of climate change on the growth of fishes from different thermal guilds in Lakes Michigan and Huron

    USGS Publications Warehouse

    Kao, Yu-Chun; Madenjian, Charles P.; Bunnell, David B.; Lofgren, Brent M.; Perroud, Marjorie

    2015-01-01

    We used a bioenergetics modeling approach to investigate potential effects of climate change on the growth of two economically important native fishes: yellow perch (Perca flavescens), a cool-water fish, and lake whitefish (Coregonus clupeaformis), a cold-water fish, in deep and oligotrophic Lakes Michigan and Huron. For assessing potential changes in fish growth, we contrasted simulated fish growth in the projected future climate regime during the period 2043-2070 under different prey availability scenarios with the simulated growth during the baseline (historical reference) period 1964-1993. Results showed that effects of climate change on the growth of these two fishes are jointly controlled by behavioral thermoregulation and prey availability. With the ability of behavioral thermoregulation, temperatures experienced by yellow perch in the projected future climate regime increased more than those experienced by lake whitefish. Thus simulated future growth decreased more for yellow perch than for lake whitefish under scenarios where prey availability remains constant into the future. Under high prey availability scenarios, simulated future growth of these two fishes both increased but yellow perch could not maintain the baseline efficiency of converting prey consumption into body weight. We contended that thermal guild should not be the only factor used to predict effects of climate change on the growth of a fish, and that ecosystem responses to climate change should be also taken into account.

  5. Hydroacoustic estimates of fish biomass and spatial distributions in shallow lakes

    NASA Astrophysics Data System (ADS)

    Lian, Yuxi; Huang, Geng; Godlewska, Małgorzata; Cai, Xingwei; Li, Chang; Ye, Shaowen; Liu, Jiashou; Li, Zhongjie

    2017-03-01

    We conducted acoustical surveys with a horizontal beam transducer to detect fish and with a vertical beam transducer to detect depth and macrophytes in two typical shallow lakes along the middle and lower reaches of the Changjiang (Yangtze) River in November 2013. Both lakes are subject to active fish management with annual stocking and removal of large fish. The purpose of the study was to compare hydroacoustic horizontal beam estimates with fish landings. The preliminary results show that the fish distribution patterns differed in the two lakes and were affected by water depth and macrophyte coverage. The hydroacoustically estimated fish biomass matched the commercial catch very well in Niushan Lake, but it was two times higher in Kuilei Lake. However, acoustic estimates included all fish, whereas the catch included only fish >45 cm (smaller ones were released). We were unable to determine the proper regression between acoustic target strength and fish length for the dominant fish species in the two lakes.

  6. Spatial variability of mercury and polyunsaturated fatty acids in the European perch (Perca fluviatilis) - Implications for risk-benefit analyses of fish consumption.

    PubMed

    Strandberg, Ursula; Palviainen, Marjo; Eronen, Aslak; Piirainen, Sirpa; Laurén, Ari; Akkanen, Jarkko; Kankaala, Paula

    2016-12-01

    This study evaluated the spatial variability of risks and benefits of consuming fish from humic and clear lakes. Mercury in fish is a potential risk for human health, but risk assessment may be confounded by selenium, which has been suggested to counterbalance mercury toxicity. In addition to the risks, fish are also rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are known to be beneficial for cardiovascular health and brain cognitive function in humans. We found that the concentrations of EPA + DHA and mercury in European perch (Perca fluviatilis) vary spatially and are connected with lake water chemistry and catchment characteristics. The highest mercury concentrations and the lowest EPA + DHA concentrations were found in perch from humic lakes with high proportion of peatland (30-50%) in the catchment. In addition, the ratio of selenium to mercury in perch muscle was ≥1 suggesting that selenium may counterbalance mercury toxicity. The observed variation in mercury and EPA + DHA content in perch from different lakes indicate that the risks and benefits of fish consumption vary spatially, and are connected with lake water chemistry and catchment characteristics. In general, consumption of perch from humic lakes exposed humans to greater risks (higher concentrations of mercury), but provided less benefits (lower concentrations of EPA + DHA) than consumption of perch from clear lakes.

  7. Status of pelagic prey fishes in Lake Michigan, 2013

    USGS Publications Warehouse

    Warner, David M.; Farha, Steven A.; O'Brien, Timothy P.; Ogilvie, Lynn; Claramunt, Randall M.; Hanson, Dale

    2014-01-01

    Acoustic surveys were conducted in late summer/early fall during the years 1992-1996 and 2001-2013 to estimate pelagic prey fish biomass in Lake Michigan. Midwater trawling during the surveys as well as target strength provided a measure of species and size composition of the fish community for use in scaling acoustic data and providing species-specific abundance estimates. The 2013 survey consisted of 27 acoustic transects (546 km total) and 31 midwater trawl tows. Mean prey fish biomass was 6.1 kg/ha (relative standard error, RSE = 11%) or 29.6 kilotonnes (kt = 1,000 metric tons), which was similar to the estimate in 2012 (31.1 kt) and 23.5% of the long-term (18 years) mean. The numeric density of the 2013 alewife year class was 6% of the time series average and this year-class contributed 4% of total alewife biomass (5.2 kg/ha, RSE = 12%). Alewife ≥age-1 comprised 96% of alewife biomass. In 2013, alewife comprised 86% of total prey fish biomass, while rainbow smelt and bloater were 4 and 10% of total biomass, respectively. Rainbow smelt biomass in 2013 (0.24 kg/ha, RSE = 17%) was essentially identical to the rainbow smelt biomass in 2012 and was 6% of the long term mean. Bloater biomass in 2013 was 0.6 kg/ha, only half the 2012 biomass, and 6% of the long term mean. Mean density of small bloater in 2013 (29 fish/ha, RSE = 29%) was lower than peak values observed in 2007-2009 and was 23% of the time series mean. In 2013, pelagic prey fish biomass in Lake Michigan was similar to Lake Huron, but pelagic community composition differs in the two lakes, with Lake Huron dominated by bloater.

  8. Angler-caught piscivore diets reflect fish community changes in Lake Huron

    USGS Publications Warehouse

    Roseman, Edward F.; Schaeffer, Jeff; Bright, Ethan; Fielder, David G.

    2014-01-01

    Examination of angler-caught piscivore stomachs revealed that Lake Trout Salvelinus namaycush, Chinook Salmon Oncorhynchus tshawytscha, and Walleyes Sander vitreus altered theirdiets in response to unprecedented declines in Lake Huron's main-basin prey fish community.Diets varied by predator species, season, and location but were nearly always dominated numerically by some combination of Alewife Alosa pseudoharengus, Rainbow Smelt Osmerus mordax, Emerald Shiner Notropis atherinoides, Round Goby Neogobius melanostomus, or terrestrial insects. Rainbow Trout Oncorhynchus mykiss (steelhead), Coho Salmon Oncorhynchus kisutch, and Atlantic Salmon Salmo salar had varied diets that reflected higher contributions of insects. Compared with an earlier (1983–1986) examination of angler-caught predator fishes from Lake Huron, the contemporary results showed an increase in consumption of nontraditional prey (including conspecifics), use of smaller prey, and an increase in insects in the diet, suggesting that piscivores were faced with chronic prey limitation during this study. The management of all piscivores in Lake Huron will likely require consideration of the pervasive effects of changes in food webs, especially if prey fish remain at low levels.

  9. Physiological and ecological effects of increasing temperature on fish production in lakes of Arctic Alaska

    USGS Publications Warehouse

    Carey, Michael P.; Zimmerman, Christian E.

    2014-01-01

    Lake ecosystems in the Arctic are changing rapidly due to climate warming. Lakes are sensitive integrators of climate-induced changes and prominent features across the Arctic landscape, especially in lowland permafrost regions such as the Arctic Coastal Plain of Alaska. Despite many studies on the implications of climate warming, how fish populations will respond to lake changes is uncertain for Arctic ecosystems. Least Cisco (Coregonus sardinella) is a bellwether for Arctic lakes as an important consumer and prey resource. To explore the consequences of climate warming, we used a bioenergetics model to simulate changes in Least Cisco production under future climate scenarios for lakes on the Arctic Coastal Plain. First, we used current temperatures to fit Least Cisco consumption to observed annual growth. We then estimated growth, holding food availability, and then feeding rate constant, for future projections of temperature. Projected warmer water temperatures resulted in reduced Least Cisco production, especially for larger size classes, when food availability was held constant. While holding feeding rate constant, production of Least Cisco increased under all future scenarios with progressively more growth in warmer temperatures. Higher variability occurred with longer projections of time mirroring the expanding uncertainty in climate predictions further into the future. In addition to direct temperature effects on Least Cisco growth, we also considered changes in lake ice phenology and prey resources for Least Cisco. A shorter period of ice cover resulted in increased production, similar to warming temperatures. Altering prey quality had a larger effect on fish production in summer than winter and increased relative growth of younger rather than older age classes of Least Cisco. Overall, we predicted increased production of Least Cisco due to climate warming in lakes of Arctic Alaska. Understanding the implications of increased production of Least Cisco to

  10. Physiological and ecological effects of increasing temperature on fish production in lakes of Arctic Alaska.

    PubMed

    Carey, Michael P; Zimmerman, Christian E

    2014-05-01

    Lake ecosystems in the Arctic are changing rapidly due to climate warming. Lakes are sensitive integrators of climate-induced changes and prominent features across the Arctic landscape, especially in lowland permafrost regions such as the Arctic Coastal Plain of Alaska. Despite many studies on the implications of climate warming, how fish populations will respond to lake changes is uncertain for Arctic ecosystems. Least Cisco (Coregonus sardinella) is a bellwether for Arctic lakes as an important consumer and prey resource. To explore the consequences of climate warming, we used a bioenergetics model to simulate changes in Least Cisco production under future climate scenarios for lakes on the Arctic Coastal Plain. First, we used current temperatures to fit Least Cisco consumption to observed annual growth. We then estimated growth, holding food availability, and then feeding rate constant, for future projections of temperature. Projected warmer water temperatures resulted in reduced Least Cisco production, especially for larger size classes, when food availability was held constant. While holding feeding rate constant, production of Least Cisco increased under all future scenarios with progressively more growth in warmer temperatures. Higher variability occurred with longer projections of time mirroring the expanding uncertainty in climate predictions further into the future. In addition to direct temperature effects on Least Cisco growth, we also considered changes in lake ice phenology and prey resources for Least Cisco. A shorter period of ice cover resulted in increased production, similar to warming temperatures. Altering prey quality had a larger effect on fish production in summer than winter and increased relative growth of younger rather than older age classes of Least Cisco. Overall, we predicted increased production of Least Cisco due to climate warming in lakes of Arctic Alaska. Understanding the implications of increased production of Least Cisco to

  11. Physiological and ecological effects of increasing temperature on fish production in lakes of Arctic Alaska

    PubMed Central

    Carey, Michael P; Zimmerman, Christian E

    2014-01-01

    Lake ecosystems in the Arctic are changing rapidly due to climate warming. Lakes are sensitive integrators of climate-induced changes and prominent features across the Arctic landscape, especially in lowland permafrost regions such as the Arctic Coastal Plain of Alaska. Despite many studies on the implications of climate warming, how fish populations will respond to lake changes is uncertain for Arctic ecosystems. Least Cisco (Coregonus sardinella) is a bellwether for Arctic lakes as an important consumer and prey resource. To explore the consequences of climate warming, we used a bioenergetics model to simulate changes in Least Cisco production under future climate scenarios for lakes on the Arctic Coastal Plain. First, we used current temperatures to fit Least Cisco consumption to observed annual growth. We then estimated growth, holding food availability, and then feeding rate constant, for future projections of temperature. Projected warmer water temperatures resulted in reduced Least Cisco production, especially for larger size classes, when food availability was held constant. While holding feeding rate constant, production of Least Cisco increased under all future scenarios with progressively more growth in warmer temperatures. Higher variability occurred with longer projections of time mirroring the expanding uncertainty in climate predictions further into the future. In addition to direct temperature effects on Least Cisco growth, we also considered changes in lake ice phenology and prey resources for Least Cisco. A shorter period of ice cover resulted in increased production, similar to warming temperatures. Altering prey quality had a larger effect on fish production in summer than winter and increased relative growth of younger rather than older age classes of Least Cisco. Overall, we predicted increased production of Least Cisco due to climate warming in lakes of Arctic Alaska. Understanding the implications of increased production of Least Cisco to

  12. Risk and toxicity assessments of heavy metals in sediments and fishes from the Yangtze River and Taihu Lake, China.

    PubMed

    Fu, Jie; Hu, Xin; Tao, Xiancong; Yu, Hongxia; Zhang, Xiaowei

    2013-11-01

    Heavy metal pollution is one of the most serous environmental issues globally. To evaluate the metal pollution in Jiangsu Province of China, the total concentrations of heavy metals in sediments and fishes from the Yangtze River and Taihu Lake were analyzed. Ecological risk of sediments and human health risk of fish consumption were assessed respectively. Furthermore, toxicity of samples on expression of the stress responsive genes was evaluated using microbial live cell-array method. The results showed that the heavy metals concentrations in sediments from the Yangtze River were much higher than those in sediments from the Taihu Lake. However, the fishes from the Taihu Lake had higher concentrations of heavy metals than fishes from the Yangtze River. Ecological risk evaluation showed that the heavy metal contaminants in sediments from the Yangtze River posed higher risk of adverse ecological effects, while sediments from the study areas of Taihu Lake were relatively safe. Health risk assessment suggested that the heavy metals in fishes of both Yangtze River and Taihu Lake might have risk of adverse health effects to human. The toxicity assessment indicated that the heavy metals in these sediments and fishes showed transcriptional effects on the selected 21 stress responsive genes, which were involved in the pathways of DNA damage response, chemical stress, and perturbations of electron transport. Together, this field investigation combined with chemical analysis, risk assessment and toxicity bioassay would provide useful information on the heavy metal pollution in Jiangsu Province.

  13. Near shore-wetland fish movements in the Great Lakes

    EPA Science Inventory

    Linkages of Great Lakes coastal wetlands and near shore habitats are under-explored, yet 90 species of fish are known to utilize wetlands for spawning and/or nursery habitat. The duration and frequency of wetland use for pelagic species with mobile adult stages is also poorly un...

  14. Chemical dynamics in Great Lakes fish

    SciTech Connect

    Russell, R.W.

    1995-12-31

    Trophic relationships in fish communities can determine the magnification of hydrophobic organic contaminants in fish tissues. Food-chain structure and length are thought to be determinants of the degree of biomagnification within a fish community. Biomagnification of persistent organic chemicals was quantified at 3 sites along the Huron-Erie corridor. Fish were captured by gill net, seine, or impoundment net; benthic invertebrates were sampled by dredge, and plankton tows were conducted. A feeding hierarchy was developed by examining the stomach contents of individual fish. Tissue samples were prepared by grinding in anhydrous sodium sulfate, cleanup on florisil column, and analyzed for chlorinated benzenes, polychlorinated biphenyls, and chlorinated pesticides by electron capture gas chromatography. Species composition of the fish communities was different at the 3 sites due to differences in habitat. Biomagnification was observed to be greatest for chemicals of high octanol/water partition coefficient and for high trophic level fish while no biomagnification was observed for low octanol/water partition coefficient chemicals.

  15. Fish assemblages in borrow-pit lakes of the Lower Mississippi River

    USGS Publications Warehouse

    Miranda, Leandro E.; Killgore, K. J.; Hoover, J.J.

    2013-01-01

    Borrow-pit lakes encompass about a third of the lentic water habitats (by area) in the active floodplain of the Lower Mississippi River, yet little is known about their fish assemblages. We investigated whether fish assemblages supported by borrow-pit lakes resembled those in oxbow lakes to help place the ecological relevance of borrow-pit lakes in context with that of natural floodplain lakes. In all, we collected 75 fish species, including 65 species in eight borrow-pit lakes, 52 species in four riverside oxbow lakes, and 44 species in eight landside oxbow lakes. Significant differences in several species richness metrics were evident between borrow-pit lakes and landside oxbow lakes but not between borrow-pit lakes and riverside oxbow lakes. All three lake types differed in fish assemblage composition. Borrow-pit lakes and riverside oxbow lakes tended to include a greater representation of fish species that require access to diverse environments, including lentic, lotic, and palustrine habitats; fish assemblages in landside oxbow lakes included a higher representation of lacustrine species. None of the fish species collected in borrow-pit lakes was federally listed as threatened or endangered, but several were listed as species of special concern by state governments in the region, suggesting that borrow-pit lakes provide habitat for sensitive riverine and wetland fish species. Differences in fish assemblages among borrow-pit lakes were linked to engineered morphologic features, suggesting that diversity in engineering can contribute to diversity in fish assemblages; however, more research is needed to match engineering designs with fish assemblage structures that best meet conservation needs.

  16. Fish consumption by children in Canada: Review of evidence, challenges and future goals.

    PubMed

    Wine, Osnat; Osornio-Vargas, Alvaro R; Buka, Irena S

    2012-05-01

    Fish consumption is of great importance to children's health and is essential for neurodevelopment, which begins in pregnancy and continues throughout early childhood and into adolescence. However, fish consumption presents conflicting health outcomes associated with its nutritional benefits and its adverse contaminant risks, because both avoiding fish as well as the consumption of contaminated fish can potentially harm children. This may be challenging to communicate. The present review was performed to assess the current knowledge and recommendations around 'smart' fish-consumption decisions. Health Canada advises, as well as other advisories and guides, that fish should be consumed for its health benefits, while also informing consumers, especially women and children, to limit certain fish consumption. The current literature must attempt to handle the challenges inherent in communicating the dilemmas of children's fish consumption. Incorporation of new knowledge translation strategies are proposed as a means to raise the level of knowledge about optimal fish consumption practices.

  17. Potential direct and indirect effects of climate change on a shallow natural lake fish assemblage

    USGS Publications Warehouse

    Breeggemann, Jason J.; Kaemingk, Mark A.; DeBates, T.J.; Paukert, Craig P.; Krause, J.; Letvin, Alexander P.; Stevens, Tanner M.; Willis, David W.; Chipps, Steven R.

    2015-01-01

    Much uncertainty exists around how fish communities in shallow lakes will respond to climate change. In this study, we modelled the effects of increased water temperatures on consumption and growth rates of two piscivores (northern pike [Esox lucius] and largemouth bass [Micropterus salmoides]) and examined relative effects of consumption by these predators on two prey species (bluegill [Lepomis macrochirus] and yellow perch [Perca flavescens]). Bioenergetics models were used to simulate the effects of climate change on growth and food consumption using predicted 2040 and 2060 temperatures in a shallow Nebraska Sandhill lake, USA. The patterns and magnitude of daily and cumulative consumption during the growing season (April–October) were generally similar between the two predators. However, growth of northern pike was always reduced (−3 to −45% change) compared to largemouth bass that experienced subtle changes (4 to −6% change) in weight by the end of the growing season. Assuming similar population size structure and numbers of predators in 2040–2060, future consumption of bluegill and yellow perch by northern pike and largemouth bass will likely increase (range: 3–24%), necessitating greater prey biomass to meet future energy demands. The timing of increased predator consumption will likely shift towards spring and fall (compared to summer), when prey species may not be available in the quantities required. Our findings suggest that increased water temperatures may affect species at the edge of their native range (i.e. northern pike) and a potential mismatch between predator and prey could exist.

  18. 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.

  19. Mercury temporal trends in top predator fish of the Laurentian Great Lakes.

    PubMed

    Zananski, Tiffany J; Holsen, Thomas M; Hopke, Philip K; Crimmins, Bernard S

    2011-10-01

    Mercury (Hg) contamination is widespread in the Laurentian Great Lakes region and is a serious environmental concern. In anaerobic environments such as lake sediments, mercury is transformed into methylmercury (MeHg) and can biomagnify up the food chain to toxic concentrations. The Great Lakes Fish Monitoring Program (GLFMP), administered by the US EPA Great Lakes National Program Office (GLNPO), aims to monitor temporal trends of mercury in the five Great Lakes using top predator fish as biomonitors. Total Hg (THg) concentrations were measured in Great Lake fish collected between 1999 and 2009. Single factor ANOVA determined that average fish THg concentrations over this time period in the five lakes were significantly different from one another in the order of Superior > Huron > Michigan > Ontario > Erie. By fitting the data to three different models (linear, quadratic, and two-segment piecewise), it was determined that Hg concentrations in top predator fish (lake trout, or walleye in Lake Erie) are currently increasing in Lake Erie and the Apostle Island sampling site in Lake Superior. Significant decreasing trends are evident in Lakes Michigan, Ontario, and the Rockport sampling site in Lake Huron, although all of the lakes exhibit elevated concentrations in fish compared to historic concentrations. As new Hg emission controls are implemented in the US, continued monitoring of Hg in Great Lakes fish will be needed to determine if they influence the current concentrations and trends.

  20. Isolation of Mycobacteria from Frozen Fish Destined for Human Consumption

    PubMed Central

    Mediel, M. J.; Rodriguez, V.; Codina, G.; Martin-Casabona, N.

    2000-01-01

    Mycobacteria were isolated from defrost water and tissue of sole (Solea solea), hake (Merluccius merluccius), cod (Gadus morhua), ling (Genypterus blacodes), and monkfish (Lophius piscatorius) on Löwenstein-Jensen medium after incubation at different temperatures. Samples of frozen fish were obtained under sterile conditions inside a refrigeration chamber (−18 to −22°C) in a wholesale market from which these products are distributed to shops for retail sale and human consumption. PMID:10919833

  1. Persistence of neutral polymorphisms in Lake Victoria cichlid fish

    PubMed Central

    Nagl, Sandra; Tichy, Herbert; Mayer, Werner E.; Takahata, Naoyuki; Klein, Jan

    1998-01-01

    Phylogenetic trees for groups of closely related species often have different topologies, depending on the genes used. One explanation for the discordant topologies is the persistence of polymorphisms through the speciation phase, followed by differential fixation of alleles in the resulting species. The existence of transspecies polymorphisms has been documented for alleles maintained by balancing selection but not for neutral alleles. In the present study, transspecific persistence of neutral polymorphisms was tested in the endemic haplochromine species flock of Lake Victoria cichlid fish. Putative noncoding region polymorphisms were identified at four randomly selected nuclear loci and tested on a collection of 12 Lake Victoria species and their putative riverine ancestors. At all loci, the same polymorphism was found to be present in nearly all the tested species, both lacustrine and riverine. Different polymorphisms at these loci were found in cichlids of other East African lakes (Malawi and Tanganyika). The Lake Victoria polymorphisms must have therefore arisen after the flocks now inhabiting the three great lakes diverged from one another, but before the riverine ancestors of the Lake Victoria flock colonized the Lake. Calculations based on the mtDNA clock suggest that the polymorphisms have persisted for about 1.4 million years. To maintain neutral polymorphisms for such a long time, the population size must have remained large throughout the entire period. PMID:9826684

  2. Persistence of neutral polymorphisms in Lake Victoria cichlid fish.

    PubMed

    Nagl, S; Tichy, H; Mayer, W E; Takahata, N; Klein, J

    1998-11-24

    Phylogenetic trees for groups of closely related species often have different topologies, depending on the genes used. One explanation for the discordant topologies is the persistence of polymorphisms through the speciation phase, followed by differential fixation of alleles in the resulting species. The existence of transspecies polymorphisms has been documented for alleles maintained by balancing selection but not for neutral alleles. In the present study, transspecific persistence of neutral polymorphisms was tested in the endemic haplochromine species flock of Lake Victoria cichlid fish. Putative noncoding region polymorphisms were identified at four randomly selected nuclear loci and tested on a collection of 12 Lake Victoria species and their putative riverine ancestors. At all loci, the same polymorphism was found to be present in nearly all the tested species, both lacustrine and riverine. Different polymorphisms at these loci were found in cichlids of other East African lakes (Malawi and Tanganyika). The Lake Victoria polymorphisms must have therefore arisen after the flocks now inhabiting the three great lakes diverged from one another, but before the riverine ancestors of the Lake Victoria flock colonized the Lake. Calculations based on the mtDNA clock suggest that the polymorphisms have persisted for about 1.4 million years. To maintain neutral polymorphisms for such a long time, the population size must have remained large throughout the entire period.

  3. Role of self-caught fish in total fish consumption rates for recreational fishermen: Average consumption for some species exceeds allowable intake.

    PubMed

    Burger, Joanna

    2013-01-01

    Studies of fish consumption focus on recreational or subsistence fishing, on awareness and adherence to advisories, consumption patterns, and contaminants in fish. Yet the general public obtains their fish from commercial sources. In this paper I examine fish consumption patterns of recreational fishermen in New Jersey to determine: 1) consumption rates for self-caught fish and for other fish, 2) meals consumed per year, 3) average meal size, and average daily intake of mercury, and 4) variations in these parameters for commonly-consumed fish, and different methods of computing intake. Over 300 people were interviewed at fishing sites and fishing clubs along the New Jersey shore. Consumption patterns of anglers varied by species of fish. From 2 to 90 % of the anglers ate the different fish species, and between 9 and 75 % gave fish away to family or friends. Self-caught fish made up 7 to 92 % of fish diets. On average, self-caught fish were eaten for only 2 to 6 months of the year, whereas other fish (commercial or restaurant) were eaten up to 10 months a year. Anglers consumed from 5 to 36 meals of different fish a year, which resulted in intake of mercury ranging from 0.01 to 0.22 ug/kg/day. Average intake of Mako shark, swordfish, and tuna (sushi, canned tuna, self-caught tuna) exceeded the U.S. Environmental Protection Agency's oral, chronic reference dose for mercury of 0.1 ug/kg/day. However, computing intake using consumption for the highest month results in average mercury intake exceeding the reference dose for striped bass and bluefish as well. These data, and the variability in consumption patterns, have implications for risk assessors, risk managers, and health professionals.

  4. Role of self-caught fish in total fish consumption rates for recreational fishermen: Average consumption for some species exceeds allowable intake

    PubMed Central

    Burger, Joanna

    2013-01-01

    Studies of fish consumption focus on recreational or subsistence fishing, on awareness and adherence to advisories, consumption patterns, and contaminants in fish. Yet the general public obtains their fish from commercial sources. In this paper I examine fish consumption patterns of recreational fishermen in New Jersey to determine: 1) consumption rates for self-caught fish and for other fish, 2) meals consumed per year, 3) average meal size, and average daily intake of mercury, and 4) variations in these parameters for commonly-consumed fish, and different methods of computing intake. Over 300 people were interviewed at fishing sites and fishing clubs along the New Jersey shore. Consumption patterns of anglers varied by species of fish. From 2 to 90 % of the anglers ate the different fish species, and between 9 and 75 % gave fish away to family or friends. Self-caught fish made up 7 to 92 % of fish diets. On average, self-caught fish were eaten for only 2 to 6 months of the year, whereas other fish (commercial or restaurant) were eaten up to 10 months a year. Anglers consumed from 5 to 36 meals of different fish a year, which resulted in intake of mercury ranging from 0.01 to 0.22 ug/kg/day. Average intake of Mako shark, swordfish, and tuna (sushi, canned tuna, self-caught tuna) exceeded the U.S. Environmental Protection Agency’s oral, chronic reference dose for mercury of 0.1 ug/kg/day. However, computing intake using consumption for the highest month results in average mercury intake exceeding the reference dose for striped bass and bluefish as well. These data, and the variability in consumption patterns, have implications for risk assessors, risk managers, and health professionals. PMID:23914136

  5. [Pollution Characteristics and Ecological Risk Assessment of PAHs in Water and Fishes from Daqing Lakes].

    PubMed

    Wang, Xiao-di; Zang, Shu-ying; Zhang, Yu-hong; Wang, Fan; Yang, Xing; Zuo, Yi-long

    2015-11-01

    of anthracene in the gill tissue of Cyprinus carpio were significantly greater than those in the Hypophthalmichthys molitrix, while other 15 PAHs concentrations had no difference between the two species. Among the different tissues of Hypophthalmichthys molitrix or Cyprinus carpio, the concentrations of PAHs in the liver and kidney tissues which are the important tissues of PAHs accumulation were significantly greater than those in the muscle, gill and brain tissues of fish because of their pervasion ability of pollutants. The results of ecological risks of PAHs in water samples to different aquatic organism species and health risk of PAHs to human through the consumption of fish showed that low ecological risk to aquatic organism species and health risk of PAHs in the muscle of Hypophthalmichthys molitrix and Cyprinus carpio to human were observed in the 4 lake groups.

  6. [Consumption of fish and fishery products in Poland--analysis of benefits and risks].

    PubMed

    Kołodziejczyk, Monika

    2007-01-01

    Fish meat content high nutritive value and essential polyunsaturated fatty acids, while low consumption of fish and fishery products in Poland. Fat meat of Baltic sea fish can also contain higher levels of dioxins and organochlorinated contaminants. Consumption of fish and fishery products in Poland ought to include different species from various catch areas.

  7. Effects of nutrient enrichment on channel catfish growth and consumption in Mount Storm Lake, West Virginia

    USGS Publications Warehouse

    Blanc, T.J.; Margraf, F.J.

    2002-01-01

    With the objective of augmenting fish production in Mount Storm Lake, Virginia Electric and Power Company initiated a programme of phosphorus addition to increase primary production, and ultimately, channel catfish (Ictaturus punctatus) growth in the 486 ha cooling reservoir. We simulated channel catfish growth dynamics using two bioenergetics modelling scenarios: (i) effects of average reservoir temperature on growth, conversion efficiency and consumption; and (ii) effects of reservoir enrichment on growth, which is simulated by increasing feeding rates. During 1991-1993, fish were sampled monthly, but sampling was increased to every 2 weeks during the peak growing season (June-September). Most of the channel catfish collected were aged 0 year and aged 1 year with rapid annual growth rates ranging from 9.0 to 13.7 J/g. We found many age 1 250-300 mm catfish, but few beyond this size. Conversion efficiency (joules gained/joules consumed) was low at approximately 18-19%. High algae consumption (40%) was evident, but consumption of zooplankton and Asiatic clam (Corbicula sp.) increased over the study. Simulated increased feeding rates showed that channel catfish were food limited in summer and fall (July-December). Weight gains with 5 and 10% feeding increases were 6-13% and 18-38%, respectively, from the baseline. Catfish of all sizes should benefit from phosphorus additions.

  8. Great Lakes commercial fishing catch 1929-2014

    USGS Publications Warehouse

    ,

    2016-01-01

    Since 1971 the Great Lakes Science Center (GLSC), formerly known as the National Fishery Center-Great Lakes (National Biological Service), the Great Lakes Fishery Laboratory (U.S. Fish and Wildlife Service)(FWS/GLFL), and the Ann Arbor Biological Laboratory (Bureau of Commercial Fisheries), have acted as repositories for the processing, reporting, and storage of U.S. Great Lakes commercial fishery statistics. The GLSC prepares annual summaries of these data for use by federal and state resource managers and other interested public and private organizations. The data collection system was organized in 1926 by Dr. John Van Oosten of the Bureau of Fisheries and was first put to use by the State of Michigan in 1927. Commercial fishermen licensed by that state were required to submit daily fishing reports indicating gear used and amount of catch. In succeeding years the system was improved and expanded until by 1950 all the Great Lakes states and the Province of Ontario, Canada, had similar systems.

  9. Great Lakes commercial fishing catches 1929-2013

    USGS Publications Warehouse

    ,

    2015-01-01

    Since 1971 the Great Lakes Science Center (GLSC), formerly known as the National Fishery Center-Great Lakes (National Biological Service), the Great Lakes Fishery Laboratory (U.S. Fish and Wildlife Service)(FWS/GLFL), and the Ann Arbor Biological Laboratory (Bureau of Commercial Fisheries), have acted as repositories for the processing, reporting, and storage of U.S. Great Lakes commercial fishery statistics. The GLSC prepares annual summaries of these data for use by federal and state resource managers and other interested public and private organizations. The data collection system was organized in 1926 by Dr. John Van Oosten of the Bureau of Fisheries and was first put to use by the State of Michigan in 1927. Commercial fishermen licensed by that state were required to submit daily fishing reports indicating gear used and amount of catch. In succeeding years the system was improved and expanded until by 1950 all the Great Lakes states and the Province of Ontario, Canada, had similar systems.

  10. Organochlorine pesticides and polychlorinated biphenyls in fish from Lake Awassa in the Ethiopian Rift Valley: human health risks.

    PubMed

    Deribe, Ermias; Rosseland, Bjørn Olav; Borgstrøm, Reidar; Salbu, Brit; Gebremariam, Zinabu; Dadebo, Elias; Skipperud, Lindis; Eklo, Ole Martin

    2014-08-01

    Dietary intake of fish containing organic contaminants poses a potential threat to human health. In the present work, an assessment has been carried out to look at the human health risk associated with consumption of fish contaminated with organochlorine pesticides (OCPs) and polychlorinated biphenyles (PCBs) in certain fish species collected from Lake Hawassa, Ethiopia. The health risk assessment was made by comparing the concentrations of OCPs and PCBs in fish muscle tissues with reference doses given in the USEPA guidelines. Dichlorodiphenyltrichloroethanes (DDTs), endosulfans, PCBs and chloridanes were identified in fish species collected from Lake Hawassa. The most predominant pesticides were DDTs, with mean concentrations of ΣDDT ranging from 19 to 56 ng g(-1) wet weights. The highest concentrations of DDTs were found in Barbus intermedius, representing the highest trophic level. PCBs, DDT and endosulfan concentrations found in B. intermedius exceeded the reference dose for children between the ages of 0-1 year (with hazard index of above 1.0). Therefore, consumption of fish from a high trophic level (e.g. B. intermedius) from Lake Hawassa may pose a special health risk to children.

  11. Poly- and perfluoroalkylated substances (PFASs) in water, sediment and fish muscle tissue from Lake Tana, Ethiopia and implications for human exposure.

    PubMed

    Ahrens, Lutz; Gashaw, Habiba; Sjöholm, Margareta; Gebrehiwot, Solomon Gebreyohannis; Getahun, Abebe; Derbe, Ermias; Bishop, Kevin; Åkerblom, Staffan

    2016-12-01

    Lake Tana is Ethiopia's largest lake and there are plans to increase the harvest of fish from the lake. The objective of this study was to assess the levels of poly- and perfluoroalkyl substances (PFASs) in different compartments of the lake (water, sediment, and fish muscle tissue), and its implications for human exposure. The results showed higher PFAS concentrations in piscivorous fish species (Labeobarbus megastoma and Labeobarbus gorguari) than non-piscivorous species (Labeobarbus intermedius, Oreochromis niloticus and Clarias gariepinus) and also spatial distribution similarities. The ∑PFAS concentrations ranged from 0.073 to 5.6 ng L(-1) (on average, 2.9 ng L(-1)) in surface water, 0.22-0.55 ng g(-1) dry weight (dw) (on average, 0.30 ng g(-1) dw) in surface sediment, and non-detected to 5.8 ng g(-1) wet weight (ww) (on average, 1.2 ng g(-1) ww) in all fish species. The relative risk (RR) indicates that the consumption of fish contaminated with perfluorooctane sulfonate (PFOS) will likely not cause any harmful effects for the Ethiopian fish eating population. However, mixture toxicity of the sum of PFASs, individual fish consumption patterns and increasing fish consumption are important factors to consider in future risk assessments.

  12. Piscivorous birds on the saline lake Grevelingen, The Netherlands: Abundance, prey selection and annual food consumption

    NASA Astrophysics Data System (ADS)

    Doornbos, G.

    Since 1971, when the Grevelingen estuary was turned into a 108 km 2 saline lake, the number of foraging piscivorous birds has increased significantly. Up to 7000 to 10 000 Great Crested Grebes may be present on the lake, representing about half of the northwestern European breeding population. In the winter 1000 to 3000 Red-breasted Mergansers also forage here, while in summer and early autumn 500 to 800 Cormorants can be found on the lake. From December 1981 through March 1982 the food habits of the grebes and mergansers were studied by means of stomach analyses. Total annual consumption of the two fish-eating birds was estimated at 46.6 and 39.2 tons fresh weight, respectively. Gobiidae proved to be the main food source, accounting for 60% of the total intake (by weight). In addition, the grebes consumed 9.9 tons of Clupea harengus and the mergansers 11.0 tons of brown shrimps Crangon crangon. The birds tended to select the larger specimens of Gobiidae and C. crangon. The estimated amount of food consumed by these two bird species represents about 28 to 36% of the standing stocks of Gobiidae, C. harengus and Sprattus sprattus present at the arrival of the birds in September/October. Total annual consumption by all major piscivorous birds, including the populations of Cormorant and Grey Heron, was estimated at 115 tons (1.1 g FW·m -2·a -1). Over the last 10-year period the number of wintering grebes showed a positive correlation ( p < 0.01) with the density of Pomatoschistus microps during the preceding (summer) season ( i.e. the most abundant gobiid species in the lake).

  13. Cesium accumulation by fish following acute input to lakes: a comparison of experimental and Chernobyl-impacted systems.

    PubMed

    Pinder, J E; Hinton, T G; Whicker, F W; Smith, J T

    2009-06-01

    An uptake parameter u (Lkg(-1)d(-1)) and a loss rate parameter k (d(-1)) were estimated for the patterns of accumulation and loss of (133)Cs by three fish species following an experimental (133)Cs addition into a pond in South Carolina, USA. These u and k parameters were compared to similar estimates for fish from other experimental ponds and from lakes that received (137)Cs deposition from Chernobyl. Estimates of u from ponds and lakes declined with increasing potassium concentrations in the water column. Although loss rates were greater in the experimental ponds, the times required to reach maximum Cs concentrations in fish were similar between ponds and lakes, because ponds and lakes had similar retentions of Cs in the water column. The maximum Cs concentrations in fish were largely determined by initial Cs concentrations in the water column. These maximum concentrations in fish and the times required to reach these maxima are potentially useful indicators for assessments of risks to humans from fish consumption.

  14. A brief history of commercial fishing in Lake Erie

    USGS Publications Warehouse

    Applegate, Vernon C.; Van Meter, Harry D.

    1970-01-01

    Salient features of the development of the industry from about 1815 to 1968, changes in fishing gears and methods, changes in the kinds and abundance of fishes caught, and the attendant effects of disappearing species on the stability of the fishery are described. The history and present status of the walleye, yellow perch, and eight other fishes, still taken in commercial quantities, are presented in more detail and are considered in the context of their effect on the current moribund state of the U.S. fishery. Past and present contributions of Lake Erie's tributaries and northerly connecting waters to the fishery are outlined briefly. The "outlook" for the fishery under present conditions of selective overfishing for high-value species, excessive pollution, ineffective and uncoordinated regulation, and antiquated methods of handling, processing, and marketing fish are discussed, and possible solutions to these problems are suggested.

  15. Geochemical and biochemical evidence of lake overturn and fish kill at Lake Averno, Italy

    NASA Astrophysics Data System (ADS)

    Caliro, S.; Chiodini, G.; Izzo, G.; Minopoli, C.; Signorini, A.; Avino, R.; Granieri, D.

    2008-12-01

    Lake Averno is situated in the homonymous crater in the northwestern sector of the Campi Flegrei active volcanic system in Campania region, Italy. In February 2005 a fish kill event was observed in the lake, prompting a geochemical survey to ascertain the possible cause. In February 2005 a geochemical survey revealed that the lake water was unstratified chemically and isotopically, presumably, as a result of lake overturn. This fish kill phenomenon was recorded at least two other times in the past. In contrast to the February 2005 results, data collected in October 2005, shows the Lake Averno to be stratified, with an oxic epilimnion (surface to 6 m) and an anoxic hypolimnion (6 m to lake bottom at about 33 m). Chemical and isotopic compositions of Lake Averno waters suggest an origin by mixing of shallow waters with a Na-Cl hydrothermal component coupled with an active evaporation process. The isotopic composition of Dissolved Inorganic Carbon, as well as the composition of the non-reactive dissolved gas species again supports the occurrence of this mixing process. Decreasing levels of SO 4 and increasing levels of H 2S and CH 4 contents in lake water with depth, strongly suggests anaerobic bacterial processes are occurring through decomposition of organic matter under anoxic conditions in the sediment and in the water column. Sulfate reduction and methanogenesis processes coexist and play a pivotal role in the anaerobic environment of the Lake Averno. The sulfate reducing bacterial activity has been estimated in the range of 14-22 μmol m - 2 day - 1 . Total gas pressure of dissolved gases ranges between 800 and 1400 mbar, well below the hydrostatic pressure throughout the water column, excluding the possibility, at least at the survey time, of a limnic eruption. Vertical changes in the density of lake waters indicate that overturn may be triggered by cooling of epilimnetic waters below 7 °C. This is a possible phenomenon in winter periods if atmospheric

  16. PCBs in fish and their cestode parasites in Lake Victoria.

    PubMed

    Oluoch-Otiego, John; Oyoo-Okoth, Elijah; Kiptoo, Kipkorir Koross Godfrey; Chemoiwa, Emily J; Ngugi, Charles C; Simiyu, Gelas; Omutange, Elijah S; Ngure, Veronica; Opiyo, Mary A

    2016-08-01

    Polychlorinated biphenyls (PCBs) are classified as persistent organic pollutants (POPs) regulated by the Stockholm Convention (2001). Although their production and use was stopped almost three decades ago, PCBs are environmental persistent, toxic, and bioaccumulate in biota. We assessed the levels of 7 PCB congeners (IUPAC nos. 28, 52, 101, 118, 138, 153, and 180) in sediment and fish (Oreochromis niloticus, Lates niloticus, and Rastrineobola argentea) and evaluated the potential of cestode fish endoparasite (Monobothrioides sp., Proteocephalaus sp., and Ligula intestinalis) as biomonitors of PCBs in Lake Victoria, Kenya. The median concentration of Σ7PCBs in sediments and fish were 2.2-96.3 μg/kg dw and 300-3,000 μg/kg lw, respectively. At all the sampling sites, CB138, CB153, and CB180 were the dominant PCB congeners in sediment and fish samples. Compared to the muscle of the piscine host, Proteocephalaus sp. (infecting L. niloticus) biomagnified PCBs ×6-14 while Monobothrioides sp. (infecting O. niloticus) biomagnified PCBs ×4-8. Meanwhile, L. intestinalis (infecting R. argentea) biomagnified PCBs ×8-16 compared to the muscle of unparasitized fish. We demonstrate the occurrence of moderate to high levels of PCB in sediments and fish in Lake Victoria. We also provide evidence that fish parasites bioaccumulate higher levels of PCBs than their piscine hosts and therefore provide a promising biomonitor of PCBs. We urge further a long-term study to validate the use of the above cestode fish parasites as biomonitoring tools for PCBs.

  17. Perfluorooctane sulfonate (PFOS) contamination of fish in urban lakes: a prioritization methodology for lake management.

    PubMed

    Xiao, Feng; Gulliver, John S; Simcik, Matt F

    2013-12-15

    The contamination of urban lakes by anthropogenic pollutants such as perfluorooctane sulfonate (PFOS) is a worldwide environmental problem. Large-scale, long-term monitoring of urban lakes requires careful prioritization of available resources, focusing efforts on potentially impaired lakes. Herein, a database of PFOS concentrations in 304 fish caught from 28 urban lakes was used for development of an urban-lake prioritization framework by means of exploratory data analysis (EDA) with the aid of a geographical information system. The prioritization scheme consists of three main tiers: preliminary classification, carried out by hierarchical cluster analysis; predictor screening, fulfilled by a regression tree method; and model development by means of a neural network. The predictive performance of the newly developed model was assessed using a training/validation splitting method and determined by an external validation set. The application of the model in the U.S. state of Minnesota identified 40 urban lakes that may contain elevated levels of PFOS; these lakes were not previously considered in PFOS monitoring programs. The model results also highlight ongoing industrial/commercial activities as a principal determinant of PFOS pollution in urban lakes, and suggest vehicular traffic as an important source and surface runoff as a primary pollution carrier. In addition, the EDA approach was further compared to a spatial interpolation method (kriging), and their advantages and disadvantages were discussed.

  18. Comparison of patterns and knowledge of benefits and warnings of fish consumption between parents and children.

    PubMed

    Herdt-Losavio, Michele L; Lin, Shao; Chen, Ming; Luo, Ming; Tang, Jianzhong; Hwang, Syni-An

    2014-07-01

    We examined generational differences in fish consumption and knowledge of benefits/warnings of fish consumption among parents and children. This cross-sectional study gathered self-administered questionnaire data, including demographics, fish consumption behavior (including specific fish species) and knowledge of fish consumption warnings and benefits. Fish were later grouped into four categories by potential mercury contamination. Descriptive statistics were conducted for all variables comparing all adults and children. Benefit/risk knowledge variables were also descriptively analyzed among parent-child pairs only. Multivariate Poisson regression was conducted on pairs to assess risk factors for children eating higher mercury fish. 421 adults and 207 children (171 adult-child pairs) participated (family response rate: 71%). Slightly more adults (97.6%) ate fish in the last year than children (92.3%); however, there was no difference between consumption of fish by category of potential mercury contamination. Both adults (44%) and children (45%) ate high-mercury fish. In 71% of parent-child pairs, both the parent and the child knew of benefits of consuming fish; only 31% knew of warnings. Parental consumption of high or moderately-high-mercury fish was related to the child's consumption of fish in the same category. Parents and children need additional education to make better choices about fish consumption. Education should target the family and include specifics about benefits and risks.

  19. The role of depth in regulating water quality and fish assemblages in oxbow lakes

    USGS Publications Warehouse

    Goetz, Daniel B.; Miranda, Leandro E.; Kroger, Robert; Andrews, Caroline S.

    2015-01-01

    We evaluated water quality and fish assemblages in deep (> 3.0 m; N = 7) and shallow (< 1.5 m; N = 6) floodplain lakes in the intensively cultivated Yazoo River Basin (Mississippi, USA) using indirect gradient multivariate procedures. Shallow lakes displayed wide diel oxygen fluctuations, some reaching hypoxic/anoxic conditions for extended periods of time, high suspended solids, and extreme water temperatures. Conversely, deeper lakes were represented by higher visibility, stable oxygen levels, and cooler water temperatures. Fish assemblages in shallow lakes were dominated by tolerant, small-bodied fishes and those able to breathe atmospheric oxygen. Deeper lakes had a greater representation of predators and other large-bodied fishes. Our evaluation suggests fish assemblages are reflective of oxbow lakes water quality, which is shaped by depth. Understanding the interactions between depth, water quality, and fish assemblages may facilitate development of effective management plans for improving conditions necessary to sustain diverse fish assemblages in agriculturally dominated basins.

  20. Turbidity as a factor in the decline of Great Lakes fishes with special reference to Lake Erie

    USGS Publications Warehouse

    Van Oosten, John

    1948-01-01

    All of the evidence indicates, then, that soil erosion on farms and the turbidity of the water were not major factors, if operative at all, in the decline of Great Lakes fishes and that they did not make Lake Erie unsuitable for fish life.

  1. Predicting Great Lakes fish yields: tools and constraints

    USGS Publications Warehouse

    Lewis, C.A.; Schupp, D.H.; Taylor, W.W.; Collins, J.J.; Hatch, Richard W.

    1987-01-01

    Prediction of yield is a critical component of fisheries management. The development of sound yield prediction methodology and the application of the results of yield prediction are central to the evolution of strategies to achieve stated goals for Great Lakes fisheries and to the measurement of progress toward those goals. Despite general availability of species yield models, yield prediction for many Great Lakes fisheries has been poor due to the instability of the fish communities and the inadequacy of available data. A host of biological, institutional, and societal factors constrain both the development of sound predictions and their application to management. Improved predictive capability requires increased stability of Great Lakes fisheries through rehabilitation of well-integrated communities, improvement of data collection, data standardization and information-sharing mechanisms, and further development of the methodology for yield prediction. Most important is the creation of a better-informed public that will in turn establish the political will to do what is required.

  2. Deepwater demersal fish community collapse in Lake Huron

    USGS Publications Warehouse

    Riley, S.C.; Roseman, E.F.; Nichols, S.J.; O'Brien, T. P.; Kiley, C.S.; Schaeffer, J.S.

    2008-01-01

    Long-term fish community surveys were carried out in the Michigan waters of Lake Huron using bottom trawls from 1976 to 2006. Trends in abundance indices for common species (those caught in 10% or more of trawl tows) were estimated for two periods: early (1976-1991) and late (1994-2006). All common species significantly decreased in abundance during the late period with the exception of the johnny darter Etheostoma nigrum and spottail shiner Notropis hudsonius, which showed no significant trends, and the round goby Neogobius melanostomus, which increased in abundance. Percentage decreases in abundance indices between 1994-1995 and 2005-2006 ranged from 66.4% to 99.9%, and seven species decreased in abundance by more than 90%. The mean biomass of all common species in 2006 was the lowest observed in the time series and was less than 5% of that observed in the mid-1990s. The mean number of common species captured per trawl has also decreased since the mid-1990s. Several factors, including recent invasion of the lake by multiple exotic species, may have contributed to these declines, but insufficient published data are currently available to determine which factors are most important. Our observations suggest that significant changes have occurred in the ecology of Lake Huron since the mid-1990s. The extent of these changes indicates that the deepwater demersal fish community in Lake Huron is undergoing collapse.

  3. Fish faunal resurgence in Lake Nabugabo, East Africa

    USGS Publications Warehouse

    Chapman, L.J.; Chapman, Colin A.; Schofield, P.J.; Olowo, J.P.; Kaufman, L.S.; Seehausen, O.; Ogutu-Ohwayo., R.

    2003-01-01

     In Lake Nabugabo, Uganda, a small satellite of the equatorial Lake Victoria, approximately 50% of the indigenous fish species disappeared from the open waters subsequent to establishment of the introduced predatory Nile perch (   Lates niloticus ). However, several of these species persisted in wetland refugia. Over the past decade, Nile perch in Lake Nabugabo have been intensively fished. Herein we report a resurgence of some indigenous species in open waters. In a multiyear study, we used annual transects in inshore and offshore waters of exposed ( no wetland ) and wetland habitats to document the pattern of resurgence. In 1995, haplochromine cichlids were largely confined to inshore areas, particularly wetland ecotones, and were rare in Nile perch stomachs, as were most other indigenous species. By 2000 haplochromine cichlids were abundant in inshore and offshore areas of both exposed and wetland transects. Several indigenous noncichlids also reappeared in the main lake, including three of the four original mormyrid species. Between 1995 and 1999, there was a dramatic increase in the proportion of haplochromines in the diet of Nile perch. When haplochromines were rare ( 1995 ), Nile perch switched from an invertebrate-dominated diet to piscivory at a large size ( 30 cm total length ). In 2000, however, Nile perch were strongly piscivorous by 5–10 cm total length. The pattern of faunal loss and recovery in Lake Nabugabo demonstrates the importance of refugia in providing the seeds of resurgence and provides a model with which to understand some changes in Lake Victoria.

  4. Lake Roosevelt Fisheries Evaluation Program, Part C; Lake Roosevelt Pelagic Fish Study: Washington Department of Fish and Wildlife, 1998 Annual Report.

    SciTech Connect

    Baldwin, Casey; Polacek, Matt; Bonar, Scott

    2002-11-01

    Pelagic fishes, such as kokanee and rainbow trout, provide an important fishery in Lake Roosevelt; however, spawner returns and creel results have been below management goals in recent years. Our objective was to identify factors that potentially limit pelagic fish production in Lake Roosevelt including entrainment, food limitation, piscivory, and other abiotic factors. We estimated the ratio of total fish entrained through Grand Coulee Dam to the pelagic fish abundance for September and October, 1998. If the majority of these fish were pelagic species, then entrainment averaged 10-13% of pelagic fish abundance each month. This rate of entrainment could impose considerable losses to pelagic fish populations on an annual basis. Therefore, estimates of species composition of entrained fish will be important in upcoming years to estimate the proportion of stocked pelagic fish lost through the dam. Food was not limiting for kokanee or rainbow trout populations since growth rates were high and large zooplankton were present in the reservoir. Estimates of survival for kokanee were low (< 0.01 annual) and unknown for rainbow trout. We estimated that the 1997 standing stock biomass of large (>1.1 mm) Daphnia could have supported 0.08 annual survival by kokanee and rainbow trout before fish consumption would have exceeded available biomass during late winter and early spring. Therefore, if recruitment goals are met in the future there may be a bottleneck in food supply for pelagic planktivores. Walleye and northern pikeminnow were the primary piscivores of salmonids in 1996 and 1997. Predation on salmonid prey was rare for rainbow trout and not detected for burbot or smallmouth bass. Northern pikeminnow had the greatest individual potential as a salmonid predator due to their high consumptive demand; however, their overall impact was limited because of their low relative abundance. We modeled the predation impact of 273,524 walleye in 1996, and 39,075 northern pikeminnow in

  5. Interrelationships between Fish Tissue Mercury Concentrations and Water Quality for South Dakota Natural Lakes and Impoundments

    USGS Publications Warehouse

    Chipps, Steven R.; Stetler, Larry; Stone, James J.; McCutcheon, Cindy M.

    2011-01-01

    The purpose of this study was to determine whether water quality parameters commonly associated with primary productivity may be used to predict the susceptibility of a specific water body to exceed proposed fish consumption advisory limitation of 0.3 mg kg−1. South Dakota currently has nine lakes and impoundments that exceed fish tissue mercury advisory limits of 1.0 mg kg−1 total mercury, far exceeding US Environmental Protection Agency and Food and Drug Administration 0.3 mg kg−1 consumption criteria. Previous studies suggest that increased aquatic productivity may mitigate the effects of biological production and subsequent uptake of methyl mercury through bio-dilution; however, it is uncertain whether these trends may exist within highly alkaline and highly productive aquatic conditions common to South Dakota lakes and impoundments. Water quality parameters and fish tissue mercury data for northern pike and walleye were collected and assessed using existing South Dakota Department of Environment and Natural Resources and Game Fish and Parks data. The data was initially screened using both parametric linear regression and non-parametric Mann–Whitney rank sum comparisons and further assessed using binary logistic regression and stepwise logistic regression methodology. Three separate phosphorus measurements (total, total dissolved, and Trophic State Index) and pH were determined to significantly correlate with increased mercury concentrations for the northern pike-in-impoundments model. However, phosphorus surprisingly was not a strong predictor for the remaining scenarios modeled. For the northern pike-in-natural lakes models, alkalinity was the most significant water quality parameter predicting increased mercury concentrations. Mercury concentrations for the walleye-in-natural lakes models were further influenced by pH and alkalinity. The water quality and fish tissue mercury interrelationships determined within this study suggest aquatic

  6. Geophysical Investigations of Structures within Southern Fish Lake Valley, California

    NASA Astrophysics Data System (ADS)

    McBride, K.; Ferguson, J. F.; Oldow, J. S.

    2015-12-01

    The 80km Fish Lake Valley Fault Zone makes up the northern portion of the Furnace Creek - Death Valley Fault Zone, a 250km right lateral oblique strike slip system that accounts for up to 25% of the relative motion between the Pacific and North American Plates. The Cucomongo Canyon Restraining bend lies to the south of Fish Lake Valley, and causes localized uplift. The developmental history of the Cucomongo Canyon restraining bend and the resultant uplift, deformation, and displacement is the focus of an integrated study by the Miles Geoscience Center at the University of Texas at Dallas. This specific part of the study focuses on the southernmost section of Fish Lake Valley, where Paleozoic sedimentary rocks are juxtaposed with Cenozoic sediments on multiple faulted boundaries. Structural constraints are not very well known as the faults are locally obscured by Quaternary alluvial deposits of various ages. Analysis of high resolution topography, produced from LiDAR scanning performed by the Miles team, and imagery shows subtle geomorphic expressions related to faulting. A near surface geophysical survey utilizing high resolution seismic refraction and microGal gravity measurements was done to explore the subsurface beneath the alluvium. Forward models were created to identify faults and ascertain vertical offsets and orientations. The geophysical models indicate a zone of extensional deformation north of the restraining bend

  7. Status of Pelagic Prey Fishes in Lake Michigan, 2014

    USGS Publications Warehouse

    Warner, David M.; Farha, Steven A.; Claramunt, Randall M.; Hanson, Dale; O'Brien, Timothy P.

    2015-01-01

    Acoustic surveys were conducted in late summer/early fall during the years 1992-1996 and 2001-2014 to estimate pelagic prey fish biomass in Lake Michigan. Midwater trawling during the surveys as well as target strength provided a measure of species and size composition of the fish community for use in scaling acoustic data and providing species-specific abundance estimates. The 2014 survey consisted of 27 acoustic transects (603 km total) and 31 midwater trawl tows. Four additional transects were sampled in Green Bay but were not included in lakewide estimates. Mean prey fish biomass was 6.5 kg/ha [31.7 kilotonnes (kt = 1,000 metric tons)], equivalent to 69.9 million pounds, which was similar to the estimate in 2013 (29.6 kt) and 25% of the long-term (19 years) mean. The numeric density of the 2014 alewife year-class was 3% of the time series average and was the lowest observed in the 19 years of sampling. This year-class contributed <1% of total alewife biomass (4.6 kg/ha). Alewife ≥age-1 comprised 99.5% of alewife biomass. Numeric density of alewife in Green Bay was more than three times that of the main lake. In 2014, alewife comprised 71% of total prey fish biomass, while rainbow smelt and bloater were 1% and 28% of total biomass, respectively. Rainbow smelt biomass in 2014 (0.08 kg/ha) was 66% lower than in 2013, 2% of the long-term mean, and lower than in any previous year. Bloater biomass in 2014 was 1.8 kg/ha, nearly three times more than the 2013 biomass, and 20% of the long-term mean. Mean density of small bloater in 2014 (122 fish/ha) was lower than peak values observed in 2007-2009 but was similar to the time series mean (124 fish/ha). In 2014, pelagic prey fish biomass in Lake Michigan was 71% of that in Lake Huron (all basins), where the community is dominated by bloater.

  8. Investigation of Total and Methyl Mercury in Fish and Sediment of Lake Michigan

    EPA Science Inventory

    Sediment cores and fish collected between 1994 and 1996 as part of the Lake Michigan Mass Balance Project were analyzed for total and methyl mercury. Results of the fish analyses are being used to describe total and methyl mercury concentrations in forage fish and lake trout, re...

  9. Lake Erie...A Day in the Life of a Fish.

    ERIC Educational Resources Information Center

    Canning, Maureen; Dunlevy, Margie

    This elementary school teaching unit was developed as a part of a series of units that deal with Lake Erie. This unit was developed to enable children to: (1) examine a moving fish; (2) conduct experiments with a live fish; (3) understand the swimming habits of fish; (4) learn how fish breathe; (5) recognize different methods of fish protection…

  10. Fish oil reduces heart rate and oxygen consumption during exercise.

    PubMed

    Peoples, Gregory E; McLennan, Peter L; Howe, Peter R C; Groeller, Herbert

    2008-12-01

    Dietary omega-3 polyunsaturated fatty acids (PUFAs) are readily incorporated into heart and skeletal muscle membranes where, in the heart, animal studies show they reduce O2 consumption. To test the hypothesis that omega-3 PUFAs alter O2 efficiency in humans, the effects of fish oil (FO) supplementation on O2 consumption during exercise were evaluated. Sixteen well-trained men (cyclists), randomly assigned to receive 8 x 1 g capsules per day of olive oil (control) or FO for 8 weeks in a double-blind, parallel design, completed the study (control: n = 7, age 27.1 +/- 2.7 years; FO: n = 9, age 23.2 +/- 1.2 years). Subjects used an electronically braked cycle ergometer to complete peak O2 consumption tests (VO 2peak) and sustained submaximal exercise tests at 55% of peak workload (from the VO 2peak test) before and after supplementation. Whole-body O2 consumption and indirect measurements of myocardial O2 consumption [heart rate and rate pressure product (RPP)] were assessed. FO supplementation increased omega-3 PUFA content of erythrocyte cell membranes. There were no differences in VO 2peak (mL kg(-1) min(-1)) (control: pre 66.8 +/- 2.4, post 67.2 +/- 2.3; FO: pre 68.3 +/- 1.4, post 67.2 +/- 1.2) or peak workload after supplementation. The FO supplementation lowered heart rate (including peak heart rate) during incremental workloads to exhaustion (P < 0.05). In addition, the FO supplementation lowered steady-state submaximal exercise heart rate, whole-body O2 consumption, and RPP (P < 0.01). Time to voluntary fatigue was not altered by FO supplementation. This study indicates that FOs may act within the healthy heart and skeletal muscle to reduce both whole-body and myocardial O2 demand during exercise, without a decrement in performance.

  11. Clostridium botulinum Type E in Fish from the Great Lakes1

    PubMed Central

    Bott, Thomas L.; Deffner, Janet S.; McCoy, Elizabeth; Foster, E. M.

    1966-01-01

    Bott, Thomas L. (University of Wisconsin, Madison), Janet S. Deffner, Elizabeth McCoy, and E. M. Foster. Clostridium botulinum type E in fish from the Great Lakes. J. Bacteriol. 91:919–924. 1966.—The intestinal contents of more than 3,000 fish from Lakes Erie, Superior, Huron, and Michigan were examined for Clostridium botulinum type E. Demonstration of the organism was accomplished by identifying its toxin in liquid cultures inoculated with material from the alimentary tract. Incidence figures, expressed as per cent of the fish tested, were: Lake Erie, 1%; Lake Superior, 1%; Lake Huron, 4%; the main body of Lake Michigan, 9%; and Green Bay (on Lake Michigan), 57%. Thus, C. botulinum type E appears to be widely but unevenly distributed in the Great Lakes, and fish from all areas are potential carriers of it. PMID:5326102

  12. HEAVY METAL ACCUMULATION IN SEDIMENT AND FRESHWATER FISH IN U.S. ARCTIC LAKES

    EPA Science Inventory

    Metal concentrations in sediment and two species of freshwater fish (lake trout [Salvelinus namaycush], and grayling [Thymallus arcticus]} were examined in four Arctic lakes in Alaska. Concentrations of several metals were naturally high in the sediment relative to uncontaminated...

  13. MERCURY EXPOSURE FROM FISH CONSUMPTION WITHIN THE JAPANESE AND KOREAN COMMUNITIES

    EPA Science Inventory

    Public health guidance pertaining to fish consumption requires that we be cognizant of the health concerns associated with eating contaminated fish and the nutritional benefits obtained from fish consumption. In doing so, a need exists for an improved understanding of the extent ...

  14. Late Pleistocene Desiccation of Lake Victoria and Rapid Evolution of Cichlid Fishes

    NASA Astrophysics Data System (ADS)

    Johnson, Thomas C.; Scholz, Christopher A.; Talbot, Michael R.; Kelts, Kerry; Ricketts, R. D.; Ngobi, Gideon; Beuning, Kristina; Ssemmanda, Immacculate; McGill, J. W.

    1996-08-01

    Lake Victoria is the largest lake in Africa and harbors more than 300 endemic species of haplochromine cichlid fish. Seismic reflection profiles and piston cores show that the lake not only was at a low stand but dried up completely during the Late Pleistocene, before 12,400 carbon-14 years before the present. These results imply that the rate of speciation of cichlid fish in this tropical lake has been extremely rapid.

  15. Fatty acid composition of freshwater wild fish in subalpine lakes: a comparative study.

    PubMed

    Vasconi, Mauro; Caprino, Fabio; Bellagamba, Federica; Busetto, Maria Letizia; Bernardi, Cristian; Puzzi, Cesare; Moretti, Vittorio Maria

    2015-03-01

    In this study, the proximate and fatty acid compositions of the muscle tissue of 186 samples of fish belonging to fifteen species of freshwater fish harvested in subalpine lakes (bleak, shad, crucian carp, whitefish, common carp, pike, black bullhead, burbot, perch, Italian roach, roach, rudd, wels catfish, chub and tench) were investigated. Most of the fish demonstrated a lipid content in the fillet lower than 2.0 g 100 g(-1) wet weight (range 0.6-9.7). A strong relationship between feeding behavior and fatty acid composition of the muscle lipids was observed. Planktivorous fish showed the lowest amounts of n-3 fatty acids (p < 0.05), but the highest monounsaturated fatty acid (MUFA) contents, in particular 18:1n-9. Conversely, carnivorous fish showed the highest amounts of saturated fatty acids and n-3 fatty acids (p < 0.05), but the lowest MUFA contents. Omnivorous fish showed substantial proportions of n-3 fatty acids and the highest contents of n-6 fatty acids. Principal component analysis showed a distinct separation between fish species according to their feeding habits and demonstrated that the most contributing trophic markers were 18:1n-9, 18:3n-3, 22:6n-3 and 20:4n-6. The quantitative amounts n-3 polyunsaturated fatty acid in muscle tissues varied depending on the fish species, the lipid content and the feeding habits. Some species were very lean, and therefore would be poor choices for human consumption to meet dietary n-3 fatty acid requirements. Nevertheless, the more frequently consumed and appreciated fish, shad and whitefish, had EPA and DHA contents in the range 900-1,000 mg 100 g(-1) fresh fillet.

  16. Spontaneous fetal death among multigravid fertile women in relation to sport fish consumption and PCB exposure, New York State Angler Study

    SciTech Connect

    Mendola, P.

    1994-01-01

    Spontaneous fetal death, a sentinel event for environmental reproductive toxicity, has been observed among various mammalian species following polychlorinated biphenyl (PCB) exposure. This exposure-based cohort study assessed the relationship between PCB exposure due to consumption of contaminated Lake Ontario sport fish and spontaneous fetal death. Using 1,820 women from the 1990-1991 New York State Angler Study, fish consumption data were obtained from food frequency questionnaires and reproductive histories from live birth certificates. A reliability study demonstrated an excellent level of agreement between the exact number of spontaneous fetal deaths recorded on the birth certificate compared with telephone interview data (kappa = 0.83). Women who had never eaten Lake Ontario sport fish were unexposed (n = 979) and 841 women reported various levels of exposure. Analyses were stratified by maternal gravidity and controlled for smoking status and maternal age. No significant increases in risk for spontaneous fetal death were seen for any estimate of PCB exposure including lifetime estimate of PCB exposure based on species-specific PCB levels, years of fish consumption, and kilograms of fish consumed, either in the 1990-1991 season or in a lifetime estimate. The only significant finding was a slight risk reduction for women of gravidity three or more with years of fish consumption (odds ratio = 0.97; p = 0.03; 95% confidence interval = 0.94-0.99). These findings suggest that PCB exposure from contaminated sport fish does not increase the risk of spontaneous fetal death.

  17. Lake level fluctuations synchronize genetic divergences of cichlid fishes in African lakes.

    PubMed

    Sturmbauer, C; Baric, S; Salzburger, W; Rüber, L; Verheyen, E

    2001-02-01

    Water level fluctuations are important modulators of speciation processes in tropical lakes, in that they temporarily form or break down barriers to gene flow among adjacent populations and/or incipient species. Time estimates of the most recent major lowstands of the three African Great Lakes are thus crucial to infer the relative timescales of explosive speciation events in cichlid species flocks. Our approach combines geological evidence with genetic divergence data of cichlid fishes from the three Great East African Lakes derived from the fastest-evolving mtDNA segment. Thereby, we show for each of the three lakes that individuals sampled from several populations which are currently isolated by long geographic distances and/or deep water form clusters of equally closely related haplotypes. The distribution of identical or equally closely related haplotypes in a lake basin allows delineation of the extent of lake level fluctuations. Our data suggest that the same climatic phenomenon synchronized the onset of genetic divergence of lineages in all three species flocks, such that their most recent evolutionary history seems to be linked to the same external modulators of adaptive radiation. A calibration of the molecular clock of the control region was elaborated by gauging the age of the Lake Malawi species flock through the divergence among the utaka-cichlid and the mbuna-cichlid lineages to minimally 570,000 years and maximally 1 Myr. This suggests that the low-lake-level period which established the observed patterns of genetic relatedness dates back less than 57,000 years, probably even to 17,000-12,400 years ago, when Lake Victoria dried up and Lakes Malawi and Tanganyika were also low. A rapid rise of all three lakes about 11,000 years ago established the large-scale population subdivisions observed today. Over that period of time, a multitude of species originated in Lakes Malawi and Victoria with an impressive degree of morphological and ecological

  18. Prey selection for the exotic cladoceran Bythotrephes cederstroemi by selected Lake Erie fishes

    USGS Publications Warehouse

    Bur, Michael T.; Klarer, David M.

    1991-01-01

    The importance of zooplankton in the diet of yellow perch (Perca flavescens), white perch (Morone americana), walleyes (Stizostedion vitreum vitreum), and white bass (M. chry-sops)was assessed in the central basin of Lake Erie in 1985–1988. Zooplankton were collected by vertical hauls in 1987–1988 and fish with a rock-hopper trawl. Although copepods (calanoid and cyciopoid) were the major zooplankton in the plankton samples, they were not well represented in the fish diet. From 1985 through 1988, Cladocera became an increasingly important food – particularly a recent invader from Europe, Bythotrephes cederstroemi. It was a major component in the diet of yellow perch from June to October in both 1987 and 1988. The zooplankton consumption by white perch was more diverse until September, when B. cederstroemi became the major food item.

  19. Radionuclide and heavy metal concentrations in soil, vegetation, and fish collected around and within Tsicoma Lake in Santa Clara Canyon

    SciTech Connect

    Fresquez, P.R.; Armstrong, D.R.; Naranjo, L. Jr.

    1996-03-01

    Radionuclide ({sup 3}H, {sup 90}Sr, {sup 137}Cs, {sup 238}Pu, {sup 239}Pu, total U) and heavy metal (Ag, As, Ba, Be, Cd, Cr, Hg, Ni, Pb, Sb, Se, Tl) contents were determined in soil, vegetation (overstory and understory), and fish (rainbow trout) collected around and within Tsicoma Lake in Santa Clara Canyon in 1995. All heavy metal and most radionuclide contents around or within the lake, except for U in soil, vegetation, and fish, were within or just above upper limit background. Detectable levels (where the analytical result was greater than two times counting uncertainty) of U in soils, vegetation, and fish were found in slightly higher concentrations than in background samples. Overall, however, maximum total committed effective dose equivalent (CEDE)(95% confidence level)--based on consumption of 46 lb of fish--from Tsicoma Lake (0.066 mrem/y) was within the maximum total CEDE from the ingestion of fish from the Mescalero National Fish Hatchery (background)(0.113 mrem/y).

  20. Po-210 and Pb-210 in water and fish from Taboshar uranium mining Pit Lake, Tajikistan.

    PubMed

    Skipperud, L; Jørgensen, A G; Heier, L S; Salbu, B; Rosseland, B O

    2013-09-01

    Polonium-210 in water and (210)Pb and (210)Po in different fish organs from 3 different fish species in Taboshar Pit Lake (n = 13), located in the uranium mining area in Tajikistan, and in Kairakkum Reservoir (reference lake, n = 3), have been determined as part of a Joint project between Norway, Kazakhstan, Kyrgyzstan and Tajikistan. The average activity concentration of (210)Pb and (210)Po in liver, muscle and bone of Carassius auratus was higher than the concentration in similar tissues of C. carpio and Sander lucioperca from the reference site. The accumulation of (210)Po was higher than for (210)Pb, and the accumulation of (210)Po was highest in the liver of C. auratus (3673 ± 434 Bq kg(-1) ww). Although the average activity concentration of (210)Pb in liver and bones of C. auratus from Pit Lake were fairly similar, a huge variation in the liver activity concentrations (25-327 Bq kg(-1) ww) was found. The results confirm direct uptake of unsupported (210)Po into the liver, and that the distributions of (210)Po and (210)Pb in fish organs were different. The BCF (L/kg) for (210)Po in bone, liver and muscle clearly demonstrates high accumulation of (210)Po in C. auratus, especially in the liver. The average BCFs of liver, bone and muscle were >1.4 × 10(5), >2.5 × 10(4) and >1.4 × 10(4), respectively. All fish in the Pit Lake were found to be in the same trophic level, however, a linear correlation between log (210)Po in liver and δ(15)N could indicate biomagnification of (210)Po in liver of C. auratus. In regards to the recommended Annual Limit of Intake (ALI) for (210)Po, the concentration of (210)Po in muscle tissues of C. auratus is alarming, as there is a high probability for the local population at risk to exceed the recommended ALI through consumption of fish from Taboshar Pit Lake.

  1. PCDD/Fs and dioxin-like PCBs in fish species from Lake Victoria, East Africa.

    PubMed

    Ssebugere, Patrick; Kiremire, Bernard T; Henkelmann, Bernhard; Bernhöft, Silke; Kasozi, Gabriel N; Wasswa, John; Schramm, Karl-Werner

    2013-07-01

    Two commercially important fish species, Nile perch (Lates niloticus) and Nile tilapia (Oreochromis niloticus) belonging to different trophic levels were collected from the Napoleon Gulf and Thurston Bay in Lake Victoria. Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) were extracted from the fish muscles and livers using the (13)C isotope dilution method, followed by multiple column chromatography clean-up. Analysis was achieved by a high resolution gas chromatography coupled with a high resolution mass spectrometer. The concentrations of analytes ranged from 0.07 to 0.59pgg(-1) fresh weight (fw) and 0.3-19.0pgg(-1) in L. niloticus and 0.06-0.18 and 0.2-15.7pgg(-1) in O. niloticus, for ∑PCDD/Fs and ∑dl-PCBs, respectively. Differences in congener concentrations were observed between the two fish species and study sites, and this was attributed to differences in feeding habits and trophic levels. World Health Organization-toxic equivalents (WHO-TEQs) were in the range 0.01-0.16pgTEQg(-1) for the PCDD/Fs and 0.001-0.74pgTEQg(-1) for the dl-PCBs. The TEQ values in the present study were lower compared to those of most fish samples reported in literature and were within permissible levels recommended by the European Union, implying that the fish was fit for human consumption.

  2. BIRTH DEFECTS RISK ASSOCIATED WITH MATERNAL SPORT FISH CONSUMPTION: POTENTIAL EFFECT MODIFICATION BY SEX OF OFFSPRING

    EPA Science Inventory

    Contaminated sport fish consumption may result in exposure to various reproductive and developmental toxicants, including pesticides and other suspected endocrine disruptors. We investigated the relation between maternal sport fish meals and risk of major birth defects among infa...

  3. Environmental variables measured at multiple spatial scales exert uneven influence on fish assemblages of floodplain lakes

    USGS Publications Warehouse

    Dembkowski, Daniel J.; Miranda, Leandro E.

    2014-01-01

    We examined the interaction between environmental variables measured at three different scales (i.e., landscape, lake, and in-lake) and fish assemblage descriptors across a range of over 50 floodplain lakes in the Mississippi Alluvial Valley of Mississippi and Arkansas. Our goal was to identify important local- and landscape-level determinants of fish assemblage structure. Relationships between fish assemblage structure and variables measured at broader scales (i.e., landscape-level and lake-level) were hypothesized to be stronger than relationships with variables measured at finer scales (i.e., in-lake variables). Results suggest that fish assemblage structure in floodplain lakes was influenced by variables operating on three different scales. However, and contrary to expectations, canonical correlations between in-lake environmental characteristics and fish assemblage structure were generally stronger than correlations between landscape-level and lake-level variables and fish assemblage structure, suggesting a hierarchy of influence. From a resource management perspective, our study suggests that landscape-level and lake-level variables may be manipulated for conservation or restoration purposes, and in-lake variables and fish assemblage structure may be used to monitor the success of such efforts.

  4. Centrarchid assemblages in Mississippi state-operated fishing lakes

    USGS Publications Warehouse

    Olive, J.A.; Miranda, L.E.; Hubbard, W.D.

    2005-01-01

    We evaluated electrofishing catch per effort in 27 state-operated fishing lakes in Mississippi to identify patterns of centrarchid community composition and to determine whether those patterns were related to selected environmental characteristics and to artificial nutrient enrichment. Ordination with detrended correspondence analysis recognized two major axes accounting for 77% of the variability in species ordination. Axis 1 showed a distinct separation between the body sizes of various species. A notable exception was the density of small (<30 cm) largemouth bass Micropterus salmoides, which aligned with the large individuals of other centrarchid species. This pattern suggested that through predation, high densities of small largemouth bass exerted significant control over the size structure of fish communities. Axis 2 separated species of crappies Pomoxis spp., suggesting that conditions other than strong species interactions also moderated the composition of crappies in the assemblages. However, neither lake morphometry nor watershed composition exhibited a major influence over axes 1 or 2. In small, intensively managed lakes with low habitat complexity, the regulatory importance of biotic interactions may overwhelm that of abiotic factors. Nutrient enrichment influenced community structure by changing the densities of bluegill Lepomis macrochirus and largemouth bass substantially but had a minor or no effect on other species. The management techniques used in these state-operated lakes are usually targeted toward a particular species without adequately considering the other species within the community. Our results show that attention to community-level interactions could provide valuable insight into factors that affect the quality of the fishery, insight that is not available through traditional population-level assessments. ?? Copyright by the American Fisheries Society 2005.

  5. Hair mercury concentrations and fish consumption patterns in Florida residents.

    PubMed

    Schaefer, Adam M; Jensen, Emily L; Bossart, Gregory D; Reif, John S

    2014-06-26

    Mercury exposure through the consumption of fish and shellfish represents a significant public health concern in the United States. Recent research has demonstrated higher seafood consumption and subsequent increased risk of methylmercury exposure among subpopulations living in coastal areas. The identification of high concentrations of total mercury in blood and skin among resident Atlantic bottlenose dolphins (Tursiops truncatus) in the Indian River Lagoon (IRL), a coastal estuary in Florida, alerted us to a potential public health hazard in the contiguous human population. Therefore, we analyzed hair mercury concentrations of residents living along the IRL and ascertained their sources and patterns of seafood consumption. The total mean mercury concentration for 135 residents was 1.53 ± 1.89 µg/g. The concentration of hair mercury among males (2.02 ± 2.38 µg/g) was significantly higher than that for females (0.96 ± 0.74 µg/g) (p < 0.01). Log transformed hair mercury concentration was significantly associated with the frequency of total seafood consumption (p < 0.01). Individuals who reported consuming seafood once a day or more were 3.71 (95% CI 0.84-16.38) times more likely to have a total hair mercury concentration over 1.0 µg/g, which corresponds approximately to the U.S. EPA reference dose, compared to those who consumed seafood once a week or less. Hair mercury concentration was also significantly higher among individuals who obtained all or most of their seafood from local recreational sources (p < 0.01). The elevated human mercury concentrations mirror the elevated concentrations observed in resident dolphins in the same geographical region. The current study is one of the first to apply the concept of a sentinel animal to a contiguous human population.

  6. Hair Mercury Concentrations and Fish Consumption Patterns in Florida Residents

    PubMed Central

    Schaefer, Adam M.; Jensen, Emily L.; Bossart, Gregory D.; Reif, John S.

    2014-01-01

    Mercury exposure through the consumption of fish and shellfish represents a significant public health concern in the United States. Recent research has demonstrated higher seafood consumption and subsequent increased risk of methylmercury exposure among subpopulations living in coastal areas. The identification of high concentrations of total mercury in blood and skin among resident Atlantic bottlenose dolphins (Tursiops truncatus) in the Indian River Lagoon (IRL), a coastal estuary in Florida, alerted us to a potential public health hazard in the contiguous human population. Therefore, we analyzed hair mercury concentrations of residents living along the IRL and ascertained their sources and patterns of seafood consumption. The total mean mercury concentration for 135 residents was 1.53 ± 1.89 µg/g. The concentration of hair mercury among males (2.02 ± 2.38 µg/g) was significantly higher than that for females (0.96 ± 0.74 µg/g) (p < 0.01). Log transformed hair mercury concentration was significantly associated with the frequency of total seafood consumption (p < 0.01). Individuals who reported consuming seafood once a day or more were 3.71 (95% CI 0.84–16.38) times more likely to have a total hair mercury concentration over 1.0 µg/g, which corresponds approximately to the U.S. EPA reference dose, compared to those who consumed seafood once a week or less. Hair mercury concentration was also significantly higher among individuals who obtained all or most of their seafood from local recreational sources (p < 0.01). The elevated human mercury concentrations mirror the elevated concentrations observed in resident dolphins in the same geographical region. The current study is one of the first to apply the concept of a sentinel animal to a contiguous human population. PMID:24972033

  7. Spatially explicit measures of production of young alewives in Lake Michigan: Linkage between essential fish habitat and recruitment

    USGS Publications Warehouse

    Hook, Tomas O.; Rutherford, Edward S.; Brines, Shannon J.; Mason, Doran M.; Schwab, David J.; McCormick, Michael; Desorcie, Timothy J.

    2003-01-01

    The identification and protection of essential habitats for early life stages of fishes are necessary to sustain fish stocks. Essential fish habitat for early life stages may be defined as areas where fish densities, growth, survival, or production rates are relatively high. To identify critical habitats for young-of-year (YOY) alewives (Alosa pseud oharengus) in Lake Michigan, we integrated bioenergetics models with GIS (Geographic Information Systems) to generate spatially explicit estimates of potential population production (an index of habitat quality). These estimates were based upon YOY alewife bioenergetic growth rate potential and their salmonine predators’ consumptive demand. We compared estimates of potential population production to YOY alewife yield (an index of habitat importance). Our analysis suggested that during 1994–1995, YOY alewife habitat quality and yield varied widely throughout Lake Michigan. Spatial patterns of alewife yield were not significantly correlated to habitat quality. Various mechanisms (e.g., predator migrations, lake circulation patterns, alternative strategies) may preclude YOY alewives from concentrating in areas of high habitat quality in Lake Michigan.

  8. Lake size and fish diversity determine resource use and trophic position of a top predator in high-latitude lakes.

    PubMed

    Eloranta, Antti P; Kahilainen, Kimmo K; Amundsen, Per-Arne; Knudsen, Rune; Harrod, Chris; Jones, Roger I

    2015-04-01

    Prey preference of top predators and energy flow across habitat boundaries are of fundamental importance for structure and function of aquatic and terrestrial ecosystems, as they may have strong effects on production, species diversity, and food-web stability. In lakes, littoral and pelagic food-web compartments are typically coupled and controlled by generalist fish top predators. However, the extent and determinants of such coupling remains a topical area of ecological research and is largely unknown in oligotrophic high-latitude lakes. We analyzed food-web structure and resource use by a generalist top predator, the Arctic charr Salvelinus alpinus (L.), in 17 oligotrophic subarctic lakes covering a marked gradient in size (0.5-1084 km(2)) and fish species richness (2-13 species). We expected top predators to shift from littoral to pelagic energy sources with increasing lake size, as the availability of pelagic prey resources and the competition for littoral prey are both likely to be higher in large lakes with multispecies fish communities. We also expected top predators to occupy a higher trophic position in lakes with greater fish species richness due to potential substitution of intermediate consumers (prey fish) and increased piscivory by top predators. Based on stable carbon and nitrogen isotope analyses, the mean reliance of Arctic charr on littoral energy sources showed a significant negative relationship with lake surface area, whereas the mean trophic position of Arctic charr, reflecting the lake food-chain length, increased with fish species richness. These results were supported by stomach contents data demonstrating a shift of Arctic charr from an invertebrate-dominated diet to piscivory on pelagic fish. Our study highlights that, because they determine the main energy source (littoral vs. pelagic) and the trophic position of generalist top predators, ecosystem size and fish diversity are particularly important factors influencing function and

  9. Examining the Impact of a Public Health Message on Fish Consumption in Bermuda

    PubMed Central

    McLean Pirkle, Catherine; Peek-Ball, Cheryl; Outerbridge, Eugene; Rouja, Philippe Max

    2015-01-01

    Background In 2003 mean cord blood mercury concentrations in pregnant Bermudian women exceeded levels associated with adverse health outcomes in children. The principal mercury source was local fish species. Public health messages were developed suggesting pregnant women reduce consumption of fish species with higher mercury concentrations (e.g. swordfish), substituting species containing lower mercury concentrations, and elevated omega-3 fatty acids (e.g. anchovies). Recent evidence indicates mercury concentrations in Bermuda’s pregnant women have fallen five- fold. Objectives Assess whether changes in women’s fish eating patterns during pregnancy are consistent with the public health messaging. Determine who is making changes to their diet during pregnancy and why. Methods Mixed methods study with a cross-sectional survey of 121 pregnant women, including 13 opened-ended interviews. Health system, social vulnerability, public health messaging, and socio-demographic variables were characterized and related to changes in fish consumption during pregnancy. Qualitative data were coded according to nutritional advice messages, comprehension of communication strategies, and sources of information. Results 95% of women surveyed encountered recommendations about fish consumption during pregnancy. 75% reported modifying fish eating behaviors because of recommendations. Principal sources of information about fish consumption in pregnancy were health care providers and the Internet. 71% of women reported reducing consumption of large fish species with greater mercury levels, but 60% reported reduced consumption of smaller, low mercury fish. No participant mentioned hearing about the benefits of fish consumption. More frequent exposure to public health messages during pregnancy was associated with lower reported consumption. Bermudian born women were less likely to reduce consumption of large fish species during pregnancy. Conclusions In Bermuda, public health messages

  10. Airborne mercury deposition and watershed characteristics in relation to mercury concentrations in water, sediments, plankton, and fish of eighty northern Minnesota lakes

    SciTech Connect

    Sorensen, J.A.; Glass, G.E.; Schmidt, K.W.; Huber, J.K.; Rapp, G.R.

    1990-01-01

    In light of increasing fish consumption advisories in several states, a comprehensive multimedia database was created to answer a variety of questions. Mercury concentrations in precipitation, lake water and sediment, zooplankton, and fish were measured and analyzed together with extensive watershed and lake chemistry data for 80 lake watersheds in the study region of northeastern Minnesota including the Superior National Forest, Voyageurs National Park, and Boundary Waters Canoe Area Wilderness. Atmospheric deposition of mercury, transport, water column lifetimes, and sedimentation in lakes are determined. The factors relating mercury concentrations within the lake watershed components are analyzed and discussed. The notable correlates with mercury residue levels in northern pike of a standard length and weight (55 cm, 1.0 kg) were mercury concentrations in zooplankton and water, total organic carbon concentration, and pH. The primary source of mercury was found to be of atmospheric origin.

  11. Airborne mercury deposition and watershed characteristics in relation to mercury concentrations in water, sediments, plankton, and fish of eighty northern Minnesota lakes

    SciTech Connect

    Sorenson, J.A.; Schmidt, K.W.; Huber, J.K.; Rapp, G.R. Jr. ); Glass, G.E. )

    1990-11-01

    In light of increasing fish consumption advisories in several states, a comprehensive multimedia database was created to answer a variety of questions. Mercury concentrations in precipitation, lake water and sediment, zooplankton, and fish were measured and analyzed together with extensive watershed and lake chemistry data for 80 lake watersheds in the study region of northeastern Minnesota including the Superior National Forest, Voyageurs National Park, and Boundary Waters Canoe Area Wilderness. Atmospheric deposition of mercury, transport, water column lifetimes, and sedimentation in lakes are determined. The factors relating mercury concentrations within the lake watershed components are analyzed and discussed. The notable correlates with mercury residue levels in northern pike of a standard length and weight (55 cm, 1.0 kg) were mercury concentrations in zooplankton and water, total organic carbon concentration, and pH. The primary source of mercury was found to be of atmospheric origin.

  12. Role of lake-wide prey fish survey in understanding ecosystem dynamics and managing fisheries of Lake Michigan

    USGS Publications Warehouse

    Madenjian, Charles P.; Edsall, T.; Munawar, M.

    2005-01-01

    With this study, the role of this lake-wide prey fish survey in both understanding the dynamics of the Lake Michigan ecosystem and managing Lake Michigan fisheries was documented. The complexity of ecosystems is such that long-term study is required before the dynamics of the ecosystem can be understoond. Furthermore, long-term observation is needed before important or meaningful questions about ecosystem dynamics can be asked. My approach is to first illustrate, by example, the usefulness of the survey results in providing insights into the dynamics of the Lake Michigan ecosystem. Then, examples of direct application of the survey results toward Lake Michigan fisheries management are presented.

  13. Human biomonitoring to optimize fish consumption advice: reducing uncertainty when evaluating benefits and risks.

    PubMed

    Arnold, Scott M; Lynn, Tracey V; Verbrugge, Lori A; Middaugh, John P

    2005-03-01

    National fish consumption advisories that are based solely on assessment of risk of exposure to contaminants without consideration of consumption benefits result in overly restrictive advice that discourages eating fish even in areas where such advice is unwarranted. In fact, generic fish advisories may have adverse public health consequences because of decreased fish consumption and substitution of foods that are less healthy. Public health is on the threshold of a new era for determining actual exposures to environmental contaminants, owing to technological advances in analytical chemistry. It is now possible to target fish consumption advice to specific at-risk populations by evaluating individual contaminant exposures and health risk factors. Because of the current epidemic of nutritionally linked disease, such as obesity, diabetes, and cardiovascular disease, general recommendations for limiting fish consumption are ill conceived and potentially dangerous.

  14. Status and trends in the fish community of Lake Superior, 2012

    USGS Publications Warehouse

    Gorman, Owen T.; Evrard, Lori M.; Cholwek, Gary A.; Vinson, Mark

    2015-01-01

    Due to ship mechanical failures, nearshore sampling was delayed from mid-May to mid-June to mid-June to late August. The shift to summer sampling when the lake was stratified may have affected our estimates, thus our estimates of status and trends for the nearshore fish community in 2012 are tentative, pending results of future surveys. However, the results of the 2012 survey are comparable with those during 2009 and 2010 when lake-wide fish biomass declined to < 1.40 kg/ha. Declines in prey fish biomass since the late 1990s can be attributed to a combination of increased predation by recovered lake trout populations and infrequent and weak recruitment by the principal prey fishes, cisco and bloater. In turn declines in lake trout biomass since the mid-2000s are likely linked to declines in prey fish biomass. If lean and siscowet lake trout populations in nearshore waters continue to remain at current levels, predation mortality will likely maintain the relatively low prey fish biomass observed in recent years. Alternatively, if lake trout populations show a substantial decline in abundance in upcoming years, prey fish populations may rebound in a fashion reminiscent to what occurred in the late 1970s to mid-1980s. However, this scenario depends on substantial increases in harvest of lake trout, which seems unlikely given that levels of lake trout harvest have been flat or declining in many regions of Lake Superior since 2000.

  15. Trophic status and helminth infracommunities of fish populations in Kashmir Himalayan lakes.

    PubMed

    Shah, H B; Yousuf, A R; Chishti, M Z; Shahnaz, S; Ahmad, F

    2014-09-01

    The present study considers the influence of the trophic status of three Kashmir Himalayan lakes on the patterns of helminth infracommunities in populations of three species of fish during 2006 to 2008. Data were collected from three lakes of differing trophic status in the Kashmir Himalayas, namely Anchar, a hyper(eu)trophic lake; Dal, a eutrophic lake; and Manasbal, a meso(eu)trophic lake. Three species of fish examined included the native fish Schizothorax niger Heckel and two exotic species--Carassius carassius (Linnaeus) and Cyprinus carpio Linnaeus. The analysis of data showed a clear habitat effect on the abundance pattern of helminth species, thus revealing lake-specific differences in parasite infracommunities of both S. niger and C. carassius. Helminth infracommunity richness was the highest in host populations from the Anchar lake compared to other two lakes. Low values in the Manasbal lake emphasize the low diversity of their helminth infracommunities. On the other hand, there was no observed pattern of community structure in the case of C. carpio in the three lake sites. However due to bias in sampling there was no distinct effect of fish body size on parasite infracommunity structure, although the present results do show that fish parasite data can be meaningful in diagnosing changes in the trophic condition of eutrophic lakes.

  16. Fish Lake, Utah - shallow seismic investigation of a lake-filled high-altitude graben

    NASA Astrophysics Data System (ADS)

    Harris, M. S.; Oliviera-Manna, M.; Bailey, C.; Marchetti, D. W.; Brunelle, A.; Abbott, M. B.; Larsen, D. J.; Stoner, J. S.; Grimm, E. C.; Donovan, J.; Anderson, L.; Power, M. J.; Chavez, V.; Carter, V.; Hart, I.

    2015-12-01

    Fish Lake formed in a portion of the 20-km x 2.5-km wide NE-SW trending graben within the High Plateaus of Utah, on the border between the Basin and Range to the west and the Canyon Lands east. This presentation focuses on the shallow seismic stratigraphic architecture of the lake. Marchetti et al. (this meeting) focuses details of a shallow core collected in 2014. With a lake surface at 2700m, avg. depth of 27m (max 37m), the lake is flanked NW by a 15° slope up to a formerly glaciated Hightop plateau (3545m) and is bound to the SE by a 30° NW facing slope off the Mytoge crest (3050m). The drainage basin is 74 km2 with ~75% of the catchment draining the Hightop from four distinct streams. Pelican Canyon (glaciated) and Doctor Canyon (unglaciated) provide most drainage into the basin, with Bowery and Twin creeks draining only the slope. These streams flow through organic-rich meadows at the edge of the lake. Only one small stream drains NW into the lake from the small Crater Lakes graben (2850m) off the Mytoge. Bathymetric surveys in the lake highlight a submerged moraine to the NE, a gently sloping bottom that reaches maximum depth off the steep wall to the SE, and small delta-form features off each of the creeks on the NW edge. Chirp seismic surveys (2-16 kHz) consistently penetrate the upper 40-m (up to ~55m). The oldest visible reflectors rise into the submerged moraine to the NE, ending in a complex set of truncated and discontinuous beds eluding to soft sediment push at the front of the glacier. Along the edge near the creeks to the NW, multiple sets of downlapping reflectors, gas pockets, and chaotic beds with lobate tops define what we interpret as deltaic deposition, possible lower lake levels with marsh systems, and slope failures. The majority of the lake is underlain by flat-lying reflectors that bound sedimentary packages spanning the entirety of the basin interior. The uppermost layers have recently been cored where seismic reflectors are continuous

  17. Survey design for lakes and reservoirs in the United States to assess contaminants in fish tissue

    EPA Science Inventory

    The National Lake Fish Tissue Study (NLFTS) was the first survey of fish contamination in lakes and reservoirs in the 48 conterminous states based on probability survey design. This study included the largest set (268) of persistent, bioaccumulative, and toxic (PBT) chemicals ev...

  18. SPATIAL PATTERNS IN ASSEMBLAGE STRUCTURES OF PELAGIC FORAGE FISH AND ZOOPLANKTON IN WESTERN LAKE SUPERIOR

    EPA Science Inventory

    This manuscript reports on the spatial distribution of zooplankton and forage fish in western Lake Superior. Fish and zooplankton assemblages are shown to differ substantially in abundance and size structure both between the open lake and nearshore regions and between two differe...

  19. MERGANSER: an empirical model to predict fish and loon mercury in New England lakes

    USGS Publications Warehouse

    Shanley, James B.; Moore, Richard; Smith, Richard A.; Miller, Eric K.; Simcox, Alison; Kamman, Neil; Nacci, Diane; Robinson, Keith; Johnston, John M.; Hughes, Melissa M.; Johnston, Craig; Evers, David; Williams, Kate; Graham, John; King, Susannah

    2012-01-01

    MERGANSER (MERcury Geo-spatial AssessmeNtS for the New England Region) is an empirical least-squares multiple regression model using mercury (Hg) deposition and readily obtainable lake and watershed features to predict fish (fillet) and common loon (blood) Hg in New England lakes. We modeled lakes larger than 8 ha (4404 lakes), using 3470 fish (12 species) and 253 loon Hg concentrations from 420 lakes. MERGANSER predictor variables included Hg deposition, watershed alkalinity, percent wetlands, percent forest canopy, percent agriculture, drainage area, population density, mean annual air temperature, and watershed slope. The model returns fish or loon Hg for user-entered species and fish length. MERGANSER explained 63% of the variance in fish and loon Hg concentrations. MERGANSER predicted that 32-cm smallmouth bass had a median Hg concentration of 0.53 μg g-1 (root-mean-square error 0.27 μg g-1) and exceeded EPA's recommended fish Hg criterion of 0.3 μg g-1 in 90% of New England lakes. Common loon had a median Hg concentration of 1.07 μg g-1 and was in the moderate or higher risk category of >1 μg g-1 Hg in 58% of New England lakes. MERGANSER can be applied to target fish advisories to specific unmonitored lakes, and for scenario evaluation, such as the effect of changes in Hg deposition, land use, or warmer climate on fish and loon mercury.

  20. Effect of boat noise and angling on lake fish behaviour.

    PubMed

    Jacobsen, L; Baktoft, H; Jepsen, N; Aarestrup, K; Berg, S; Skov, C

    2014-06-01

    The effects of disturbances from recreational activities on the swimming speed and habitat use of roach Rutilus rutilus, perch Perca fluviatilis and pike Esox lucius were explored. Disturbances were applied for 4 h as (1) boating in short intervals with a small outboard internal combustion engine or (2) boating in short intervals combined with angling with artificial lures between engine runs. The response of the fish species was evaluated by high-resolution tracking using an automatic acoustic telemetry system and transmitters with sub-minute burst rates. Rutilus rutilus swimming speed was significantly higher during disturbances [both (1) and (2)] with an immediate reaction shortly after the engine started. Perca fluviatilis displayed increased swimming activity during the first hour of disturbance but not during the following hours. Swimming activity of E. lucius was not significantly different between disturbance periods and the same periods on days without disturbance (control). Rutilus rutilus increased their use of the central part of the lake during disturbances, whereas no habitat change was observed in P. fluviatilis and E. lucius. No difference in fish response was detected between the two types of disturbances (boating with and without angling), indicating that boating was the primary source of disturbance. This study highlights species-specific responses to recreational boating and may have implications for management of human recreational activities in lakes.

  1. A National Probabilistic Study of Polybrominated Diphenyl Ethers in Fish from US Lakes and Reservoirs

    EPA Science Inventory

    National estimates were developed for polybrominated diphenyl ethers (PBDEs) in fish from lakes and reservoirs of the conterminous United States (excluding the Laurentian Great Lakes and Great Salt Lake) using an unequal probability design. Predator (fillet) and bottom-dweller (w...

  2. RELATIVE ABUNDANCE OF TOTAL AND METHYL MERCURY IN 1994-5 LAKE MICHIGAN FORAGE FISH

    EPA Science Inventory

    As part of the Lake Michigan Mass Balance Project, forage fish samples were collected in 1994-5 from three regions within Lake Michigan: Saugatuck, Michigan and Port Washington and Sturgeon Bay, Wisconsin by the USGS Great Lakes Science Center in Ann Arbor, Michigan. Species of ...

  3. Higher fish but lower micronutrient intakes: Temporal changes in fish consumption from capture fisheries and aquaculture in Bangladesh.

    PubMed

    Bogard, Jessica R; Farook, Sami; Marks, Geoffrey C; Waid, Jillian; Belton, Ben; Ali, Masum; Toufique, Kazi; Mamun, Abdulla; Thilsted, Shakuntala H

    2017-01-01

    Malnutrition is one of the biggest challenges of the 21st century, with one in three people in the world malnourished, combined with poor diets being the leading cause of the global burden of disease. Fish is an under-recognised and undervalued source of micronutrients, which could play a more significant role in addressing this global challenge. With rising pressures on capture fisheries, demand is increasingly being met from aquaculture. However, aquaculture systems are designed to maximise productivity, with little consideration for nutritional quality of fish produced. A global shift away from diverse capture species towards consumption of few farmed species, has implications for diet quality that are yet to be fully explored. Bangladesh provides a useful case study of this transition, as fish is the most important animal-source food in diets, and is increasingly supplied from aquaculture. We conducted a temporal analysis of fish consumption and nutrient intakes from fish in Bangladesh, using nationally representative household expenditure surveys from 1991, 2000 and 2010 (n = 25,425 households), combined with detailed species-level nutrient composition data. Fish consumption increased by 30% from 1991-2010. Consumption of non-farmed species declined by 33% over this period, compensated (in terms of quantity) by large increases in consumption of farmed species. Despite increased total fish consumption, there were significant decreases in iron and calcium intakes from fish (P<0.01); and no significant change in intakes of zinc, vitamin A and vitamin B12 from fish, reflecting lower overall nutritional quality of fish available for consumption over time. Our results challenge the conventional narrative that increases in food supply lead to improvements in diet and nutrition. As aquaculture becomes an increasingly important food source, it must embrace a nutrition-sensitive approach, moving beyond maximising productivity to also consider nutritional quality. Doing

  4. A quantitative risk-benefit analysis of changes in population fish consumption.

    PubMed

    Cohen, Joshua T; Bellinger, David C; Connor, William E; Kris-Etherton, Penny M; Lawrence, Robert S; Savitz, David A; Shaywitz, Bennett A; Teutsch, Steven M; Gray, George M

    2005-11-01

    Although a rich source of n-3 polyunsaturated fatty acids (PUFAs) that may confer multiple health benefits, some fish contain methyl mercury (MeHg), which may harm the developing fetus. U.S. government recommendations for women of childbearing age are to modify consumption of high-MeHg fish, while recommendations encourage fish consumption among the general population because of nutritional benefits. To investigate the aggregate impacts of hypothetical shifts in fish consumption, the Harvard Center for Risk Analysis convened an expert panel (see acknowledgements). Effects investigated include prenatal cognitive development, coronary heart disease mortality, and stroke. Substitution of fish with high MeHg concentrations with fish containing less MeHg among women of childbearing age yields substantial developmental benefits and few negative impacts. However, if women instead decrease fish consumption, countervailing risks substantially reduce net benefits. If other adults (mistakenly and inappropriately) also reduce their fish consumption, the net public health impact is negative. Although high compliance with recommended fish consumption patterns can improve public health, unintended shifts in consumption can lead to public health losses. Risk managers should investigate and carefully consider how populations will respond to interventions, how those responses will influence nutrient intake and contaminant exposure, and how these changes will affect aggregate public health.

  5. Too much of a good thing? Update on fish consumption and mercury exposure.

    PubMed

    Levenson, Cathy W; Axelrad, Donald M

    2006-03-01

    While there is a significant amount of data showing health benefits of increased fish consumption, there are conflicting reports about the cardiovascular risks of mercury in seafood. A recent long-term study attempted to resolve this controversy, providing an opportunity to balance recommendations from the US Environmental Protection Agency for mercury with those from the American Heart Association for fish consumption.

  6. Inter-household and intra-household patterns of fish and meat consumption in fishing communities in two states in Nigeria.

    PubMed

    Gomna, Ahmed; Rana, Krishen

    2007-01-01

    Fish is generally regarded as a primary source of protein for many poor African fishing communities. The present study compared the relative importance of fish as a high-quality dietary protein source with meat in fishing communities in two states in Nigeria. Fifty fishing households in which active fishing was the primary activity and fifty non-fishing households (agriculture being stated as primary activity) in traditional fishing communities were randomly selected in the coastal state of Lagos and the inland state of Niger. A simple weighing balance was designed and given to each household to measure fish or meat entering the household for consumption. A comparison of consumption using this method against the 24h recall method revealed that the recall method accounted for only one third of actual fish consumed. Overall, the price of fish was higher and consumption lower in Lagos compared with Niger State. At the household level in both states, the consumption of fish in fishing households was twice that of non-fishing households, whereas meat consumption was similar. A total of thirty-nine different fish species were consumed, with Tilapia contributing 24% by weight of the fish consumed. In both states, beef was the most frequently consumed meat, followed by goat meat. The study revealed a high preference for fresh fish. The highest fish consumption occurred in March, corresponding to the period of lowest meat consumption. On a unit weight basis, heads of households consumed 59% more fish than their wives or children.

  7. Resident Fish Planning: Dworshak Reservoir, Lake Roosevelt and Lake Pend Oreille.

    SciTech Connect

    Fickeisen, Duane H.; Geist, David R.

    1994-01-01

    Research projects are presently being conducted to reduce the amount of uncertainty in how reservoir operations within the Columbia River federal power system affect resident fish. Many of these research projects are being conducted to better define operation strategies being proposed under the Columbia River System Operation Review (SOR). This project provides a basis for understanding the potential effects of different operating strategies being considered under the SOR in reservoir fisheries at Lake Roosevelt, Dworshak Reservoir, and Lake Pend Oreille. The methodological framework used here was adapted from the Regional Assessment of Supplementation Project (RASP), a project framework used for evaluating supplementation strategies for anadromous fish. RASP attempts to diagnose the factors that limit production of fishes and outlines a process that can be followed to systematically reduce uncertainty while achieving the objective. In all three reservoirs concerns exist about protecting sensitive species, particularly bull trout and cutthroat trout. In all three reservoirs a need exists for additional baseline information to provide an adequate understanding of the populations of interest.

  8. Dynamic hypoxic zones in Lake Erie compress fish habitat, altering vulnerability to fishing gears

    USGS Publications Warehouse

    Kraus, Richard T.; Knight, Carey T.; Farmer, Troy M.; Gorman, Ann Marie; Collingsworth, Paris D.; Warren, Glenn J.; Kocovsky, Patrick M.; Conroy, Joseph D.

    2015-01-01

    Seasonal degradation of aquatic habitats from hypoxia occurs in numerous freshwater and coastal marine systems and can result in direct mortality or displacement of fish. Yet, fishery landings from these systems are frequently unresponsive to changes in the severity and extent of hypoxia, and population-scale effects have been difficult to measure except in extreme hypoxic conditions with hypoxia-sensitive species. We investigated fine-scale temporal and spatial variability in dissolved oxygen in Lake Erie as it related to fish distribution and catch efficiencies of both active (bottom trawls) and passive (trap nets) fishing gears. Temperature and dissolved oxygen loggers placed near the edge of the hypolimnion exhibited much higher than expected variability. Hypoxic episodes of variable durations were frequently punctuated by periods of normoxia, consistent with high-frequency internal waves. High-resolution interpolations of water quality and hydroacoustic surveys suggest that fish habitat is compressed during hypoxic episodes, resulting in higher fish densities near the edges of hypoxia. At fixed locations with passive commercial fishing gear, catches with the highest values occurred when bottom waters were hypoxic for intermediate proportions of time. Proximity to hypoxia explained significant variation in bottom trawl catches, with higher catch rates near the edge of hypoxia. These results emphasize how hypoxia may elevate catch rates in various types of fishing gears, leading to a lack of association between indices of hypoxia and fishery landings. Increased catch rates of fish at the edges of hypoxia have important implications for stock assessment models that assume catchability is spatially homogeneous.

  9. The past and future of fish consumption: Can supplies meet healthy eating recommendations?

    PubMed

    Thurstan, Ruth H; Roberts, Callum M

    2014-12-15

    In many developed countries fish and shellfish are increasingly promoted as healthy alternatives to other animal protein. We analysed how much fish was available to UK and global populations after accounting for processing losses, and compared this to recommended levels of fish consumption. In 2012, UK domestic fish landings per capita fell 81% below the recommended intake, although declines were masked by increased imports and aquaculture from the 1970s onwards. Global wild fish supply per capita declined by 32% from its peak in 1970. However, overall fish supplies per capita increased by 10% over the same period due to rapidly expanding aquaculture production. Whilst aquaculture has so far prevented a downturn in global fish supplies, many developed nations continue to aspire to consume more fish than they produce. Until demand is balanced with sustainable methods of production governments should consider carefully the social and environmental implications of greater fish consumption.

  10. Fish consumption pattern among adults of different ethnics in Peninsular Malaysia

    PubMed Central

    Ahmad, Nurul Izzah; Wan Mahiyuddin, Wan Rozita; Tengku Mohamad, Tengku Rozaina; Ling, Cheong Yoon; Daud, Siti Fatimah; Hussein, Nasriyah Che; Abdullah, Nor Aini; Shaharudin, Rafiza; Sulaiman, Lokman Hakim

    2016-01-01

    Background Understanding different patterns of fish consumption is an important component for risk assessment of contaminants in fish. A few studies on food consumption had been conducted in Malaysia, but none of them focused specifically on fish consumption. The objectives of this study were to document the meal pattern among three major ethnics in Malaysia with respect to fish/seafood consumption, identify most frequently consumed fish and cooking method, and examine the influence of demographic factors on pattern of fish consumption among study subjects. Methods A cross-sectional survey was conducted between February 2008 and May 2009 to investigate patterns of fish consumption among Malaysian adults in Peninsular Malaysia. Adults aged 18 years and above were randomly selected and fish consumption data were collected using a 3-day prospective food diary. Results A total of 2,675 subjects, comprising male (44.2%) and female (55.7%) participants from major ethnics (Malays, 76.9%; Chinese, 14.7%; Indians, 8.3%) with a mean age of 43.4±16.2 years, were involved in this study. The results revealed 10 most frequently consumed marine fish in descending order: Indian mackerel, anchovy, yellowtail and yellow-stripe scads, tuna, sardines, torpedo scad, Indian and short-fin scads, pomfret, red snapper, and king mackerel. Prawn and squid were also among the most preferred seafood by study subjects. The most frequently consumed freshwater fish were freshwater catfish and snakehead. The most preferred cooking style by Malaysians was deep-fried fish, followed by fish cooked in thick and/or thin chili gravy, fish curry, and fish cooked with coconut milk mixed with other spices and flavorings. Overall, Malaysians consumed 168 g/day fish, with Malay ethnics’ (175±143 g/day) consumption of fish significantly (p<0.001) higher compared with the other two ethnic groups (Chinese=152±133 g/day, Indians=136±141 g/day). Conclusion Fish consumption was significantly associated with

  11. Accumulation of metals in three fish species from the Yaounde Municipal Lake in Cameroon.

    PubMed

    Léopold, Ekengele Nga; Jung, Myung Chae; Emmanuel, Ekodeck Georges

    2015-09-01

    Metals are dangerous to aquatic organisms and they can bioaccumulate in the food chain and represent risk for humans. In order to appraise their levels in fish species, concentrations of various elements including Na, Mg, K, Ca, Al, Fe, Mn, Cr, Ni, Co, Cd, Cu, Pb, Zn, Ba, and Sr were determined in the muscles and gills of three fish species (Oreochromis niloticus, Sarotherodon galilaeus, and Clarias sp.) which are more fished and consumed in the Yaounde Municipal Lake, Cameroon. According to chemical results of the fish samples analyzed by ICP-AES, the concentrations of metals (mg kg(-1), wet tissues) in those fish tissues varied as follows for the muscle (and gill) Na 1480-3780 (4180-9310), Mg 897-1250 (843-1450), K 9600-18,500 (6020-10,400), Ca 430-3900 (22,200-62,400), Al 8.10-615 (113-951), Fe 12.0-725 (307-1160), Mn 1.61-30.1 (14.3-433), Cr 1.58-267 (0.31-35.4), Ni 0.16-1.85 (1.06-2.82), Co 0.10-0.47 (0.07-0.16), Cd 0.11-0.23 (0.10-0.22), Cu 0.59-5.13 (1.31-5.13), Pb 1.11-5.12 (2.56-5.74), Zn 15.4-47.2 (45.3-69.2), Ba 0.61-51.15 (0.35-83.2), and Sr 2.31-5.74 (2.09-5.75). The results revealed that Na, Ca, Zn, Fe, and Mn were higher concentrated in the gills than in the muscles, while K, Cr, Ni, Co, and Cd were more concentrated in the muscles of the species. In addition, all the elements were bioaccumulated in the fish species and the bioaccumulation factors (BAFs) were decreased in the following order: Cr > Ni > Zn > Al > Ca > Pb > Mn > Ba > K > Fe > Mg > Cu > Na > Sr > Co > Cd. Compared to international standards, Pb, Cd, Cr, Ni, and Zn were over the recommendations of the European Community, WHO, and Norwegian guidance values for human health. Therefore, fishes from the Yaounde Municipal Lake are not advised for human consumption as toxic elements might be taken above the recommended levels.

  12. Development of a new Lake-wide Multiple Gear Survey to Assess Status and Trends of the Lake Superior Fish Community and Lower Trophic Levels

    EPA Science Inventory

    The U.S. Geological Survey Great Lakes Science Center has developed a plan to implement revision of its annual fish community survey of Lake Superior. The primary objective of the revision is improvement of the sampling design to be more representative of the Lake Superior fish c...

  13. Long term trends of fish after liming of Swedish streams and lakes

    NASA Astrophysics Data System (ADS)

    Holmgren, Kerstin; Degerman, Erik; Petersson, Erik; Bergquist, Björn

    2016-12-01

    Thousands of Swedish acidified lakes and streams have been regularly limed for about 30 years. Standard sampling of fish assemblages in lakes and streams was an important part of monitoring the trends after liming, i.e. sampling with multi-mesh gillnets in lakes (EN 14757) and electrofishing in streams (EN 14011). Monitoring data are nationally managed, in the National Register of Survey test-fishing and the Swedish Electrofishing Register. We evaluated long-term data from 1029 electrofishing sites in limed streams and gillnet sampling in 750 limed lakes, along with reference data from 195 stream sites and 101 lakes with no upstream liming in their catchments. The median year of first liming was 1986 for both streams and lakes. The proportion of limed stream sites with no fish clearly decreased with time, mean species richness and proportion of sites with brown trout (Salmo trutta) recruits increased. There were no consistent trends in fish occurrence or species richness at non-limed sites, but occurrence of brown trout recruits also increased in acid as well as neutral reference streams. Abundance of brown trout, perch (Perca fluviatilis) and roach (Rutilus rutilus) increased significantly more at limed sites than at non-limed reference sites sampled before and after 1986. The mean species richness did not change consistently in limed lakes, but decreased in low alkalinity reference lakes, and fish abundance decreased significantly in limed as well as in non-limed lakes.

  14. Phylogeny and historical demography of endemic fishes in Lake Biwa: the ancient lake as a promoter of evolution and diversification of freshwater fishes in western Japan.

    PubMed

    Tabata, Ryoichi; Kakioka, Ryo; Tominaga, Koji; Komiya, Takefumi; Watanabe, Katsutoshi

    2016-04-01

    To elucidate the origins of the endemic fish of Lake Biwa, an ancient lake in Japan, and the role of the lake in the diversification of freshwater fish in western Japan, we established a molecular phylogenetic framework with an absolute time scale and inferred the historical demography of a large set of fish species in and around the lake. We used mtDNA sequences obtained from a total of 190 specimens, including 11 endemic species of Lake Biwa and their related species, for phylogenetic analyses with divergence time estimations and from a total of 2319 specimens of 42 species (including 14 endemics) occurring in the lake for population genetic analyses. Phylogenetic analysis suggested that some of the endemic species diverged from their closest relatives earlier (1.3-13.0 Ma) than the period in which the present environmental characteristics of the lake started to develop (ca. 0.4 Ma), whereas others diverged more recently (after 0.4 Ma). In contrast, historical demographic parameters suggested that almost all species, including endemic and nonendemic ones, expanded their populations after the development of the present lake environment. In phylogeographic analyses, common or very close haplotypes of some species were obtained from Lake Biwa and other regions of western Japan. The phylogenetic and historical demographic evidence suggests that there was a time lag between phylogenetic divergence and population establishment and that phenotypic adaptation of some endemic species to the limnetic environment occurred much later than the divergences of those endemic lineages. Population structure and phylogeographic patterns suggest that Lake Biwa has functioned not only as the center of adaptive evolution but also as a reservoir for fish diversity in western Japan.

  15. Radium-226 in water, sediments, and fish from lakes near the city of Elliot Lake, Ontario, Canada.

    PubMed

    Clulow, F V; Davé, N K; Lim, T P; Avadhanula, R

    1998-01-01

    Ra-226 was measured by alpha-emission spectroscopy in water, sediments, and fish (tissues and gut contents), from five lakes in a watershed containing U mining and milling operations at Elliot Lake, Ontario, and from control lakes in an adjacent non-industrialized watershed. Ra-226 transfer parameters from lake water and sediments to fish tissues, and annual intakes by humans consuming fish, were estimated. Mean dissolved 226Ra levels ranged from approximately 76 mBq litre(-1) in water of the most affected lake, to < 10 mBq litre(-1) in control lakes. Levels in summer were consistently higher than in fall or winter; no consistent variation with depth was noted. Sediment levels ranged from approximately 3000 mBq g(-1) dry wt in one study lake to < 100 mBq g(-1) dry wt of sediment in control lakes. Bone 226Ra concentrations were higher than in muscle. The lake trout (Salvelinus namaycush), a predatory secondary consumer, had bone 226Ra levels (< 20 mBq g(-1) dry wt) that did not show significant site variation. In contrast, bottom feeding whitefish had significantly more 226Ra in bone tissue (to 38 mBq g(-1) dry wt in the lake whitefish, Coregonus clupeaformis, and 76 mBq g(-1) in round whitefish, Prosopium cylindraceum) in study lakes than in controls (< 20 mBq g(-1) dry wt). Ra-226 levels in lake trout muscle were low and showed erratic variation among lakes whereas levels in whitefish muscle did not vary significantly among study and control sites. Lake herring (= cisco, Coregonus artedii), a planktivorous fish taken only from Quirke Lake, had mean 226Ra levels of 18 and 1.4 mBq g(-1) dry wt in bone and muscle, respectively. Gut 226Ra levels, highest in lake trout from McCabe and Quirke Lakes (126 +/- 53, 64 +/- 44 mBq g(-1) dry wt, respectively), and just detectable in McCabe and Elliot Lake whitefish (24 +/- 2, 36 +/- 14 mBq g(-1) dry wt, respectively), were below detection in lake trout and whitefish from other lakes. Concentration ratios (CRs) of 226Ra from

  16. Efficacy of risk-based, culturally sensitive Ogaa (walleye) consumption advice for Anishinaabe tribal members in the Great Lakes Region.

    PubMed

    DeWeese, Adam D; Kmiecik, Neil E; Chiriboga, Esteban D; Foran, Jeffery A

    2009-05-01

    The Great Lakes Indian Fish and Wildlife Commission (GLIFWC) has produced Ogaa (walleye-Sander vitreus) consumption advisories since 1996 for Anishinaabe from GLIFWC member tribes in the 1837 and 1842 ceded territories of Wisconsin. GLIFWC's advisory maps were revised in 2005 to address cultural sensitivities (to protect tribal lifeways), to utilize recent mercury exposure information, and to incorporate changes in advisory levels for methyl mercury. Lake-specific, risk-based, culturally sensitive consumption advice was provided on color-coded maps for two groups: children under age 15 years and females of childbearing age, and males 15 years and older and females beyond childbearing age. The maps were distributed to, and a behavioral intervention program developed for, the six GLIFWC member tribes in Wisconsin as well as member tribes in Minnesota and the 1842 ceded territory of Michigan. Tribal fish harvesters, tribal health care providers, women of childbearing age or with young children, tribal leaders, elders, and children were targeted specifically for the behavioral intervention. The efficacy of the behavioral intervention was assessed using surveys of 275 tribal fish harvesters from Wisconsin, 139 tribal harvesters from Michigan and Minnesota, and 156 Wisconsin women of childbearing age. Significant increases in the percentage of survey participants who indicated awareness of advisory maps occurred among Wisconsin harvesters (increase from 60% to 77%), Michigan and Minnesota harvesters (29% to 51%), and women of childbearing age in Wisconsin (40% to 87%). A significant increase in preference for smaller Ogaa occurred among tribal harvesters in Wisconsin (41% to 72%) and tribal harvesters in Michigan and Minnesota (49% to 71%), although not among women of childbearing age. The GLIFWC map-based advisory program did not adversely affect tribal harvest of Ogaa, which increased from 63,000 to 88,000 fish in the three states after the intervention.

  17. Determinism in fish assemblages of floodplain lakes of the vastly disturbed Mississippi Alluvial Valley

    USGS Publications Warehouse

    Miranda, L.E.; Lucas, G.M.

    2004-01-01

    The Mississippi Alluvial Valley between southern Illinois and southern Louisiana contains hundreds of floodplain lakes, most of which have been adversely affected by landscape modifications used to control flooding and support agriculture. We examined fish assemblages in lakes of this region to determine whether deterministic patterns developed in relation to prominent abiotic lake characteristics and to explore whether relevant abiotic factors could be linked to specific assemblage structuring mechanisms. The distributions of 14 taxa in 29 lakes were governed primarily by two gradients that contrasted assemblages in terms of lake area, lake elongation, and water clarity. The knowledge of whether a lake was clear or turbid, large or small, and long or short helped determine fish assemblage characteristics. Abiotic factors influenced fish assemblage structures, plausibly through limitations on foraging and physiological tolerances. Determinism in assemblage organization of floodplain lakes relative to recurrence in physicochemical features has been documented for unaltered rivers. Whereas the Mississippi Alluvial Valley has been subjected to vast anthropogenic disturbances and is not a fully functional floodplain river, fish assemblages in its floodplain lakes remain deterministic and organized by the underlying factors that also dictate assemblages in unaltered rivers. In advanced stages of lake aging, fish assemblages in these lakes are expected to largely include species that thrive in turbid, shallow systems with few predators and low oxygen concentrations. The observed patterns related to physical characteristics of these lakes suggest three general conservation foci, including (1) watershed management to control erosion, (2) removal of sediments or increases in water level to alleviate depth reductions and derived detriments to water physicochemistry, and (3) management of fish populations through stockings, removals, and harvest regulations.

  18. Diet shifts by planktivorous and benthivorous fishes in northern Lake Michigan in response to ecosystem changes

    USGS Publications Warehouse

    Bunnell, David B.; Davis, Bruce M.; Chriscinske, Margret Ann; Keeler, Kevin M.; Mychek-Londer, Justin G.

    2015-01-01

    In Lake Michigan, diets of planktivorous and benthivorous fishes have varied over the past decades, in part owing to food web changes. To update diet information and compare them to a similar effort in 1994–1995, we analyzed the diets of seven benthivorous and planktivorous fish species collected along two northern Lake Michigan transects that spanned nearshore (18 m), intermediate (46 m), and offshore (91, 110, 128 m) bottom depths during spring, summer, and autumn of 2010. Calanoid copepods (e.g., Limnocalanus macrurus, Leptodiaptomus sicilis, and Senecella calanoides) comprised a majority of the diets in at least one season for all sizes of alewife (Alosa pseudoharengus), bloater (Coregonus hoyi), and rainbow smelt (Osmerus mordax). Similarly, Mysis diluviana was the highest proportion in at least one season for large sizes of alewife, bloater, and rainbow smelt, as well as slimy sculpin (Cottus cognatus) and deepwater sculpin (Myoxocephalus thompsonii). The diets of the remaining two species, ninespine stickleback (Pungitius pungitius) and round goby (Neogobius melanostomus), were dominated by herbivorous cladocerans or dreissenid mussels, respectively. Interspecific diet overlap was minimal at 18 and 46 m. In offshore waters, however, overlap was relatively high, driven by frequent consumption of Mysis. Relative to 1994–1995, 2010 diets revealed increased feeding on calanoid copepods and Mysis, with corresponding declining consumption of Diporeia spp. and herbivorous cladocerans. Relative diet weight was also higher in 1994–1995 than in 2010 for small and large bloater and both sculpin species. We hypothesize that the shifts in diets are reflective of community-level changes in invertebrate prey availability.

  19. Mechanisms driving recruitment variability in fish: comparisons between the Laurentian Great Lakes and marine systems

    USGS Publications Warehouse

    Pritt, Jeremy J.; Roseman, Edward F.; O'Brien, Timothy P.

    2014-01-01

    In his seminal work, Hjort (in Fluctuations in the great fisheries of Northern Europe. Conseil Parmanent International Pour L'Exploration De La Mar. Rapports et Proces-Verbaux, 20: 1–228, 1914) observed that fish population levels fluctuated widely, year-class strength was set early in life, and egg production by adults could not alone explain variability in year-class strength. These observations laid the foundation for hypotheses on mechanisms driving recruitment variability in marine systems. More recently, researchers have sought to explain year-class strength of important fish in the Laurentian Great Lakes and some of the hypotheses developed for marine fisheries have been transferred to Great Lakes fish. We conducted a literature review to determine the applicability of marine recruitment hypotheses to Great Lakes fish. We found that temperature, interspecific interactions, and spawner effects (abundance, age, and condition of adults) were the most important factors in explaining recruitment variability in Great Lakes fish, whereas relatively fewer studies identified bottom-up trophodynamic factors or hydrodynamic factors as important. Next, we compared recruitment between Great Lakes and Baltic Sea fish populations and found no statistical difference in factors driving recruitment between the two systems, indicating that recruitment hypotheses may often be transferable between Great Lakes and marine systems. Many recruitment hypotheses developed for marine fish have yet to be applied to Great Lakes fish. We suggest that future research on recruitment in the Great Lakes should focus on forecasting the effects of climate change and invasive species. Further, because the Great Lakes are smaller and more enclosed than marine systems, and have abundant fishery-independent data, they are excellent candidates for future hypothesis testing on recruitment in fish.

  20. Successional change in the Lake Superior fish community: population trends in ciscoes, rainbow smelt, and lake trout, 1958-2008

    USGS Publications Warehouse

    Gorman, Owen T.

    2012-01-01

    The Lake Superior fish community underwent massive changes in the second half of the 20th century. Those changes are largely reflected in changes in abundance of the adults of principal prey species, the ciscoes (Coregonus spp.), the invasive rainbow smelt (Osmerus mordax), and the principal predator, lake trout (Salvelinus namaycush). To better understand changes in species abundances, a comprehensive series of gillnet and bottom trawl data collected from 1958 to 2008 were examined. In the late 1950s/early 1960s, smelt abundance was at its maximum, wild lake trout was at its minimum, and an abundance of hatchery lake trout was increasing rapidly. The bloater (Coregonus hoyi) was the prevalent cisco in the lake; abundance was more than 300% greater than the next most abundant cisco, shortjaw cisco (C. zenithicus), followed by kiyi (C. kiyi) and lake cisco (C. artedi). By the mid-1960s, abundance of hatchery lake trout was nearing maximum, smelt abundance was beginning to decline, and abundances of all ciscoes declined, but especially that of shortjaw cisco and kiyi. By the late 1970s, recovery of wild lake trout stocks was well underway and abundances of hatchery lake trout and smelt were declining and the ciscoes were reaching their nadir. During 1980–1990, the fish community underwent a dramatic shift in organization and structure. The rapid increase in abundance of wild lake trout, concurrent with a rapid decline in hatchery lake trout, signaled the impending recovery. Rainbow smelt abundance dropped precipitously and within four years, lake cisco and bloater populations rebounded on the heels of a series of strong recruitment events. Kiyi populations showed signs of recovery by 1989, and shortjaw by 2000, though well below historic maximum abundances. High abundance of adult smelt prior to 1980 appears to be the only factor linked to recruitment failure in the ciscoes. Life history traits of the cisco species were examined to better understand their different

  1. Abundances of northwestern salamander larvae in montane lakes with and without fish, Mount Rainier National Park, Washington

    USGS Publications Warehouse

    Larson, Gary L.; Hoffman, Robert L.

    2002-01-01

    In Mount Rainier National Park, the northwestern salamander usually inhabits relatively large and deep lakes and ponds (average size = 0.3 ha; average depth > 2 m) that contain flocculent, organic bottom sediments and abundant coarse wood. Prior to 1970, salmonids were introduced into many of the park's lakes and ponds that were typical habitat of the northwestern salamander. The objective of this study was to compare, in lakes and ponds with suitable habitat characteristics for northwestern salamanders, the observed abundances of larvae in takes and ponds with and without these introduced salmonids. Day surveys of 61 lakes were conducted between 1993 and 1999. Fish were limited to takes and ponds deeper than 2 in. For the 48 lakes and ponds deeper than 2 in (i.e., 25 fishless lakes and 23 fish lakes), the mean and median observed abundances of northwestern salamander larvae in fishless lakes and ponds was significantly greater than the mean and median observed abundances of larvae in lakes and ponds with fish. Northwestern salamander larvae were not observed in 11 fish lakes. These lakes were similar in median elevation, surface area, and maximum depth to the fishless lakes. The 12 fish lakes with observed larvae were significantly lower in median elevation, larger in median surface area, and deeper in median maximum depth than the fishless lakes. Low to null observed abundances of northwestern salamander larvae in lakes and ponds with fish were attributed to a combination of fish predation of larvae and changes in larval behavior.

  2. Similar morphologies of cichlid fish in Lakes Tanganyika and Malawi are due to convergence.

    PubMed

    Kocher, T D; Conroy, J A; McKaye, K R; Stauffer, J R

    1993-06-01

    The species flocks of cichlid fishes in the lakes of East Africa are the most spectacular example of adaptive radiation among living vertebrates. Similar highly derived morphologies are found among species in different lakes. These similarities have been variously interpreted either as evidence for migration of ancestral species between the lakes, or of striking convergence of morphology. To distinguish among these competing hypotheses we sequenced a portion of the mitochondrial DNA control region from six pairs of morphologically similar taxa from Lakes Malawi and Tanganyika. Our results clearly indicate a separate origin of these morphologies in the two lakes. They also suggest that the Tanganyikan radiation is relatively old, and that the species flocks in lakes Malawi and Victoria are derived from one of the ancient lineages found in Lake Tanganyika. These findings have important implications for understanding the pattern of morphological and behavioral evolution in these fish.

  3. Perceptions of health risks and benefits associated with fish consumption among Russian consumers.

    PubMed

    van Dijk, Heleen; Fischer, Arnout R H; Honkanen, Pirjo; Frewer, Lynn J

    2011-04-01

    Knowledge about differences in consumer perceptions of health risks and benefits related to fish consumption is important for the development of targeted health interventions associated with dietary choice. The purpose of this study is to identify individual differences in Russian consumers according to their perceptions of health risks and benefits associated with fish consumption. By application of a cluster analysis on perceptions of personal risks and benefits associated with the consumption of fish, four groups of Russian consumers were classified as: very positive; positive; moderately positive; and 'high risk-high benefit' about the healthiness of fish consumption. Differences in perceptions of personal risks and benefits across consumers were related to self-reported fish consumption, optimism about personal risks and benefits, and optimism about personal knowledge about risks and benefits. Implications for the development of targeted health interventions to influence perceptions of risks and benefits associated with fish consumption, and ultimately fish consumption, are discussed. It is concluded that optimism regarding perceptions and knowledge of health risks, and health benefits should be taken into account when developing interventions aimed at consumer health.

  4. Public awareness of mercury in fish: analysis of public awareness and assessment of fish consumption in vermont.

    PubMed

    Damsky, William E; Duncan, Elizabeth; Flanagan, Noreen; Fromhold, Karen; Dung, Hyunh; Meyer, Russell; Sax, Jordan; Delaney, Thomas; Bress, William; Hoffman-Contois, Razelle; Carney, Jan K

    2009-11-16

    Exposure to mercury from environmental sources, such as fish consumption, poses potential health risks to the public. The state of Vermont has developed educational brochures and posters displaying safe fish consumption guidelines in order to educate the public regarding mercury exposure through fish. In this study, a group of medical students from the University of Vermont College of Medicine, in partnership with the Vermont Department of Health, conducted a study in Chittenden County, Vermont in order to assess both fish consumption practices and overall awareness of such safe eating guidelines and mercury advisories. A total of 166 Vermont residents were surveyed during a six week period. The results of this survey suggest that in Chittenden county of Vermont, these educational efforts are markedly successful, with 48% of respondents being specifically aware of the safe eating guidelines. Further, these results suggest that 61% of those respondents that reported low monthly canned tuna consumption had a decreased their consumption in response to the safe eating guidelines. last, a series of specific, yet widely applicable recommendations are presented for future public educational efforts regarding mercury exposure through fish consumption.

  5. Fish consumption recommendations to conform to current advice in regard to mercury intake.

    PubMed

    Vieira, H C; Morgado, F; Soares, A M V M; Abreu, S N

    2015-07-01

    This article reviews fish consumption data, mercury tolerable intake values, and mercury (Hg) content in fish, based on several reports from the Food and Agriculture Organization and European Union. The study assumptions are valid based on the current established USEPA reference dose (RfD). Combining the number of meals (per week), amount of fish ingested (by meal), and levels of MeHg in fish, this study calculates and presents isocurves indicating the maximum number of fishmeal per week without exceeding the USEPA RfD for methylmercury (MeHg). RfD are assumed to be the "exposure dose that is likely to be without deleterious effect even if continued exposure occurs over a lifetime." The study points out that even considering a single 50-g fish meal per week, the USEPA RfD would be exceeded, triggered by values above 0.84 μg g(-1) of MeHg in fish, and this despite being allowed levels up to 1.0 μg g(-1) of MeHg in fish consumption!-Have we a health risk? Fish consumption is expected to be relatively stable, while anthropogenic mercury emissions are expected to stabilize or even to increase beyond current values. How many meals of fish per week can we have, combining the number of fish meals per week, amount of fish ingested by meal, and levels of MeHg in fish?

  6. Fish consumption does not prevent increase in waist circumference in European women and men.

    PubMed

    Jakobsen, Marianne U; Due, Karen M; Dethlefsen, Claus; Halkjaer, Jytte; Holst, Claus; Forouhi, Nita G; Tjønneland, Anne; Boeing, Heiner; Buijsse, Brian; Palli, Domenico; Masala, Giovanna; Du, Huaidong; van der A, Daphne L; Wareham, Nicholas J; Feskens, Edith J M; Sørensen, Thorkild I A; Overvad, Kim

    2012-09-01

    Fish consumption is the major dietary source of EPA and DHA, which according to rodent experiments may reduce body fat mass and prevent obesity. However, human studies have suggested that fish consumption has no appreciable association with body-weight gain. We investigated the associations between fish consumption and subsequent change in waist circumference. Sex, age and waist circumference at enrolment were considered as potential effect modifiers. Women and men (n 89 432) participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) were followed for a median of 5·5 years. Mixed-effect linear regression was used to investigate the associations between fish consumption and subsequent change in waist circumference. Among all participants, the average annual change in waist circumference was - 0·01 cm/10 g higher total fish consumption per d (95 % CI - 0·01, 0·00) and - 0·01 cm/10 g higher fatty fish consumption per d (95 % CI - 0·02, - 0·01), after adjustment for potential confounders. Lean fish consumption was not associated with change in waist circumference. Adjustment for potential over- or underestimation of fish consumption measurements did not systematically change the observed associations, but the 95 % CI became slightly wider. The results in subgroups from analyses stratified by sex, age or waist circumference at enrolment were not systematically different. In conclusion, the present study suggests that fish consumption does not prevent increase in waist circumference.

  7. Great Lakes and St. Lawrence Seaway Navigation Season Extension. Volume V. Appendix G. Fish and Wildlife Coordination Act Report.

    DTIC Science & Technology

    1979-08-01

    dominant fish species in Lake Huron . High fecundity, relative absence of predators and effectiveness as a filter feeder has given the alewife a competitive...intensive commercial fishing for large ciscoes and increased competition from the small bloater and alewife in Lakes Michigan and Huron . 254 ( A substantial...were introduced to Lakes Huron and Michigan to help control the alewife and provide game fish. Lake populations depend on hatchery plantings. As the ice

  8. Structure and function of fish communities in the southern Lake Michigan basin with emphasis on restoration of native fish communities

    USGS Publications Warehouse

    Simon, Thomas P.; Stewart, Paul M.

    1999-01-01

    The southern Lake Michigan basin in northwest Indiana possesses a variety of aquatic habitats including riverine, palustrine, and lacustrine systems. The watershed draining this area is a remnant of glacial Lake Chicago and supports fish communities that are typically low in species richness. Composition of the presettlement Lake Michigan fish community near the Indiana Dunes has been difficult to reconstruct. Existing data indicate that the number of native species in the Lake Michigan watershed, including nearshore Lake Michigan, has declined by 22% since the onset of European settlement. Few remnants of natural fish communities exist, and those occur principally in the ponds of Miller Woods, the Grand Calumet Lagoons, and the Little Calumet River. These communities have maintained a relatively diverse assemblage of fishes despite large-scale anthropogenic disturbances in the area, including channelization, massive river redirection, fragmentation, habitat alteration, exotic species invasions, and the introduction of toxic chemicals. Data that we collected from 1985 to 1996 suggested that the Grand Calumet River has the highest proportion of exotic fish species of any inland wetland in northwest Indiana. Along the Lake Michigan shoreline, another group of exotics (e.g., round goby, alewife, and sea lamprey) have affected the structure of native fish communities, thereby altering lake ecosystem function. Stocking programs contribute to the impairment of native communities. Nonindigenous species have restructured the function of Lake Michigan tributaries, causing disruptions in trophic dynamics, guild structure, and species diversity. Several fish communities have been reduced or eliminated by the alteration and destruction of spawning and nursery areas. Degradation of habitats has caused an increase in numbers and populations of species able to tolerate and flourish when confronted with hydrologic alteration. Fish communities found on public lands in northwest

  9. Expanding perceptions of subsistence fish consumption: evidence of high commercial fish consumption and dietary mercury exposure in an urban coastal community.

    PubMed

    Holloman, Erica L; Newman, Michael C

    2012-02-01

    Through collaborative partnerships established between current researchers and The Moton Community House (a local community center), African American women (ages 16-49yrs) from the Southeast Community of Newport News, Virginia, USA were surveyed to assess the reproducibility and consistency of fish consumption patterns (ingestion rates, exposure frequencies, weight, and fish consumption rates) derived from a community-specific fish consumption survey. Women were also surveyed to assess the reliability of the survey responses, and to estimate daily mercury intake. Fish consumption patterns were reproducible and the survey responses were reliable. Comparison between years revealed that fish consumption patterns remained consistent over time. In addition, the high fish consumption rate estimated in 2008 (147.8g/day; 95% CI: 117.6-185.8g/day) was confirmed with a rate (134.9g/day; 95% CI: 88-207g/day) not materially different and still considerably higher than mean fish consumption rates reported for U.S. women. Daily mercury intake rates were estimated using consumption data from 2008 and three consumption scenarios (canned white, canned light, and no tuna) due to confirmed differences in mercury concentration between canned white and light tuna. Arithmetic mean daily mercury intake rates were 0.284μg/kg bw/day (95% CI: 0.229-0.340μg/kg bw/day) using canned white tuna, 0.212μg/kg bw/day (95% CI: 0.165-0.259μg/kg bw/day) using light tuna, and 0.197μg/kg bw/day (95% CI: 0.151-0.243μg/kg bw/day) using no tuna. Approximately 58%-73% of the daily mercury intake rates for African American women in the Southeast Community exceeded US EPA's oral reference dose (RfD) of 0.10μg/kg bw/day for mercury. In addition, 2% of the rates exceeded a level (1.00μg/kg bw/day) documented to produce adverse health effects. Past and current investigations confirmed that even though women in this community were not subsistence fishers, they are subsistence fish consumers.

  10. Bioaccumulation of Dechloranes, organophosphate esters, and other flame retardants in Great Lakes fish.

    PubMed

    Guo, Jiehong; Venier, Marta; Salamova, Amina; Hites, Ronald A

    2017-04-01

    We measured the concentrations of 60 flame retardants (and related compounds) in fish samples collected in the Great Lakes basin. These analytes include dechlorane-related compounds (Decs), organophosphate esters (OPEs), and brominated flame retardants (BFRs). Composite lake trout (Salvelinus namaycush) or walleye (Sander vitreus, from Lake Erie) samples were collected (N=3 for each lake) in 2010 from each of the five Great Lakes (a total of 15 samples). Among the dechlorane-related compounds, Dechlorane, Dechlorane Plus, Dechlorane-602, Dechlorane-603, and Dechlorane-604 (with zero to three bromines and with four chlorines) were detected in >73% of the fish samples. The concentrations of some of these dechlorane-related compounds were 3-10 times higher in Lake Ontario trout than in fish from the other four lakes. Tris(1-chloroisopropyl) phosphate, tri-n-butylphosphate, tris(2-chloroethyl)phosphate, and triphenyl phosphate were found in >50% of the fish samples. Polybrominated diphenyl ethers (PBDEs) were the most abundant of the flame retardants in fish, with a mean concentration of 250ng/g lipid. Our findings suggest that the Decs and BFRs with 3-6 bromines are more bioaccumulative in the fish than the OPEs and high molecular weight BFRs.

  11. Factors of ecologic succession in oligotrophic fish communities of the Laurentian Great Lakes

    USGS Publications Warehouse

    Smith, Stanford H.

    1972-01-01

    Oligotrophic fish communities of the Great Lakes have undergone successive disruptions since the mid-1800s. Major contributing factors have been intensive selective fisheries, extreme modification of the drainage, invasion of marine species, and progressive physical–chemical changes of the lake environments. Lake Ontario was the first to be affected as its basin was settled and industrialized earliest, and it was the first to be connected by canals to the mid-Atlantic where the alewife (Alosa pseudoharengus) and sea lamprey (Petromyzon marinus) which ultimately became established in the Great Lakes were abundant. Oligotrophic fish communities were successively disrupted in Lakes Erie, Huron, Michigan, and Superior as the affects of population growth, industrialization, and marine invaders spread upward in the Laurentian drainage.The degree and sequence of response of families offish and species within families differed for each factor, but the sequence of change among families and species has been the same in response to each factor as it affected various lakes at different times. The ultimate result of the disruption of fish communities has been a reduction of productivity of oligotrophic species that ranges from extreme in Lake Ontario to moderate in Lake Superior, and which has reached a state of instability and rapid change in the upper three Great Lakes by the rnid-1900s similar to the situation in Lake Ontario in the mid-1800s. Since oligotrophic species (primarily salmonines, coregonines, and deepwater cottids) are the only kinds of fish that fully occupied the entire volume of the deepwater Great Lakes (Ontario, Huron, Michigan, and Superior), the fish biomass of these lakes has been reduced as various species declined or disappeared. In Lake Erie, which is shallow, and in the shallow bays of the deep lakes, oligotrophic species were replaced by mesotrophic species, primarily percids, which have successively increased and declined. All oligotrophic

  12. Hierarchy in factors affecting fish biodiversity in floodplain lakes of the Mississippi Alluvial Valley

    USGS Publications Warehouse

    Dembkowski, D.J.; Miranda, L.E.

    2012-01-01

    River-floodplain ecosystems offer some of the most diverse and dynamic environments in the world. Accordingly, floodplain habitats harbor diverse fish assemblages. Fish biodiversity in floodplain lakes may be influenced by multiple variables operating on disparate scales, and these variables may exhibit a hierarchical organization depending on whether one variable governs another. In this study, we examined the interaction between primary variables descriptive of floodplain lake large-scale features, suites of secondary variables descriptive of water quality and primary productivity, and a set of tertiary variables descriptive of fish biodiversity across a range of floodplain lakes in the Mississippi Alluvial Valley of Mississippi and Arkansas (USA). Lakes varied considerably in their representation of primary, secondary, and tertiary variables. Multivariate direct gradient analyses indicated that lake maximum depth and the percentage of agricultural land surrounding a lake were the most important factors controlling variation in suites of secondary and tertiary variables, followed to a lesser extent by lake surface area. Fish biodiversity was generally greatest in large, deep lakes with lower proportions of watershed agricultural land. Our results may help foster a holistic approach to floodplain lake management and suggest the framework for a feedback model wherein primary variables can be manipulated for conservation and restoration purposes and secondary and tertiary variables can be used to monitor the success of such efforts. ?? 2011 Springer Science+Business Media B.V.

  13. Factors affecting fish biodiversity in floodplain lakes of the Mississippi Alluvial Valley

    USGS Publications Warehouse

    Miranda, Leandro E.; Dembkowski, Daniel J.

    2012-01-01

    River-floodplain ecosystems offer some of the most diverse and dynamic environments in the world. Accordingly, floodplain habitats harbor diverse fish assemblages. Fish biodiversity in floodplain lakes may be influenced by multiple variables operating on disparate scales, and these variables may exhibit a hierarchical organization depending on whether one variable governs another. In this study, we examined the interaction between primary variables descriptive of floodplain lake large-scale features, suites of secondary variables descriptive of water quality and primary productivity, and a set of tertiary variables descriptive of fish biodiversity across a range of floodplain lakes in the Mississippi Alluvial Valley of Mississippi and Arkansas (USA). Lakes varied considerably in their representation of primary, secondary, and tertiary variables. Multivariate direct gradient analyses indicated that lake maximum depth and the percentage of agricultural land surrounding a lake were the most important factors controlling variation in suites of secondary and tertiary variables, followed to a lesser extent by lake surface area. Fish biodiversity was generally greatest in large, deep lakes with lower proportions of watershed agricultural land. Our results may help foster a holistic approach to floodplain lake management and suggest the framework for a feedback model wherein primary variables can be manipulated for conservation and restoration purposes and secondary and tertiary variables can be used to monitor the success of such efforts.

  14. The impact of fish predation and cyanobacteria on zooplankton size structure in 96 subtropical lakes.

    PubMed

    Zhang, Jing; Xie, Ping; Tao, Min; Guo, Longgen; Chen, Jun; Li, Li; Xuezhen Zhang; Zhang, Lu

    2013-01-01

    Zooplankton are relatively small in size in the subtropical regions. This characteristic has been attributed to intense predation pressure, high nutrient loading and cyanobacterial biomass. To provide further information on the effect of predation and cyanobacteria on zooplankton size structure, we analyzed data from 96 shallow aquaculture lakes along the Yangtze River. Contrary to former studies, both principal components analysis and multiple regression analysis showed that the mean zooplankton size was positively related to fish yield. The studied lakes were grouped into three types, namely, natural fishing lakes with low nutrient loading (Type1), planktivorous fish-dominated lakes (Type 2), and eutrophic lakes with high cyanobacterial biomass (Type 3). A marked difference in zooplankton size structure was found among these groups. The greatest mean zooplankton size was observed in Type 2 lakes, but zooplankton density was the lowest. Zooplankton abundance was highest in Type 3 lakes and increased with increasing cyanobacterial biomass. Zooplankton mean size was negatively correlated with cyanobacterial biomass. No obvious trends were found in Type 1 lakes. These results were reflected by the normalized biomass size spectrum, which showed a unimodal shape with a peak at medium sizes in Type 2 lakes and a peak at small sizes in Type 3 lakes. These results indicated a relative increase in medium-sized and small-sized species in Types 2 and 3 lakes, respectively. Our results suggested that fish predation might have a negative effect on zooplankton abundance but a positive effect on zooplankton size structure. High cyanobacterial biomass most likely caused a decline in the zooplankton size and encouraged the proliferation of small zooplankton. We suggest that both planktivorous fish and cyanobacteria have substantial effects on the shaping of zooplankton community, particularly in the lakes in the eastern plain along the Yangtze River where aquaculture is widespread

  15. The Impact of Fish Predation and Cyanobacteria on Zooplankton Size Structure in 96 Subtropical Lakes

    PubMed Central

    Zhang, Jing; Xie, Ping; Tao, Min; Guo, Longgen; Chen, Jun; Li, Li; XueZhen Zhang; Zhang, Lu

    2013-01-01

    Zooplankton are relatively small in size in the subtropical regions. This characteristic has been attributed to intense predation pressure, high nutrient loading and cyanobacterial biomass. To provide further information on the effect of predation and cyanobacteria on zooplankton size structure, we analyzed data from 96 shallow aquaculture lakes along the Yangtze River. Contrary to former studies, both principal components analysis and multiple regression analysis showed that the mean zooplankton size was positively related to fish yield. The studied lakes were grouped into three types, namely, natural fishing lakes with low nutrient loading (Type1), planktivorous fish-dominated lakes (Type 2), and eutrophic lakes with high cyanobacterial biomass (Type 3). A marked difference in zooplankton size structure was found among these groups. The greatest mean zooplankton size was observed in Type 2 lakes, but zooplankton density was the lowest. Zooplankton abundance was highest in Type 3 lakes and increased with increasing cyanobacterial biomass. Zooplankton mean size was negatively correlated with cyanobacterial biomass. No obvious trends were found in Type 1 lakes. These results were reflected by the normalized biomass size spectrum, which showed a unimodal shape with a peak at medium sizes in Type 2 lakes and a peak at small sizes in Type 3 lakes. These results indicated a relative increase in medium-sized and small-sized species in Types 2 and 3 lakes, respectively. Our results suggested that fish predation might have a negative effect on zooplankton abundance but a positive effect on zooplankton size structure. High cyanobacterial biomass most likely caused a decline in the zooplankton size and encouraged the proliferation of small zooplankton. We suggest that both planktivorous fish and cyanobacteria have substantial effects on the shaping of zooplankton community, particularly in the lakes in the eastern plain along the Yangtze River where aquaculture is widespread

  16. Consumptive Water-Use Coefficients for the Great Lakes Basin and Climatically Similar Areas

    USGS Publications Warehouse

    Shaffer, Kimberly H.; Runkle, Donna L.

    2007-01-01

    Consumptive water use is the portion of water withdrawn (for a particular use) that is evaporated, transpired, incorporated into products or crops, consumed by humans or livestock, or otherwise removed from the immediate water environment. This report, which is organized by water?use categories, includes consumptive?use coefficients for the Great Lakes Basin (including Canada) and for areas climatically similar to the Great Lakes Basin. This report also contains an annotated bibliography of consumptive water?use coefficients. Selected references are listed for consumptive?use data from elsewhere in the world. For the industrial water?use category, the median consumptive?use coefficients were 10 percent for the Great Lakes Basin, climatically similar areas, and the world; the 25th and 75th percentiles for these geographic areas were comparable within 6 percent. The combined domestic and public?supply consumptive?use statistics (median, 25th and 75th percentiles) were between 10 to 20 percent for the various geographic areas. Although summary statistics were similar for coefficients in the livestock and irrigation water?use categories for the Great Lakes Basin and climatically similar areas, statistic values for the world on a whole were substantially lower (15 to 28 percent lower). Commercial and thermoelectric power consumptive?use coefficient statistics (median, 25th, and 75th percentile) also were comparable for the Great Lakes Basin and climatically similar areas, within 2 percent. References for other countries were not found for commercial and thermoelectric power water?use categories. The summary statistics for the mining consumptive?use coefficients varied, likely because of differences in types of mining, processes, or equipment.

  17. Mercury in fish from three rift valley lakes (Turkana, Naivasha and Baringo), Kenya, East Africa.

    PubMed

    Campbell, L M; Osano, O; Hecky, R E; Dixon, D G

    2003-01-01

    Total mercury (THg) concentrations were measured for various fish species from Lakes Turkana, Naivasha and Baringo in the rift valley of Kenya. The highest THg concentration (636 ng g(-1) wet weight) was measured for a piscivorous tigerfish Hydrocynus forskahlii from Lake Turkana. THg concentrations for the Perciformes species, the Nile perch Lates niloticus from Lake Turkana and the largemouth bass Micropterus salmoides from Lake Naivasha ranged between 4 and 95 ng g(-1). The tilapiine species in all lakes, including the Nile tilapia Oreochromis niloticus, had consistently low THg concentrations ranging between 2 and 25 ng g(-1). In Lake Naivasha, the crayfish species, Procambrus clarkii, had THg concentrations similar to those for the tilapiine species from the same lake, which is consistent with their shared detritivore diet. THg concentrations in all fish species were usually consistent with their known trophic position, with highest concentrations in piscivores and declining in omnivores, insectivores and detritivores. One exception is the detritivore Labeo cylindricus from Lake Baringo, which had surprisingly elevated THg concentrations (mean=75 ng g(-1)), which was similar to those for the top trophic species (Clarias and Protopterus) in the same lake. Except for two Hydrocynus forskahlii individuals from Lake Turkana, which had THg concentrations near or above the international marketing limit of 500 ng g(-1), THg concentrations in the fish were generally below those of World Health Organization's recommended limit of 200 ng g(-1) for at-risk groups.

  18. PCB congener patterns in rats consuming diets containing Great Lakes salmon: Analysis of fish, diets, and adipose tissue

    SciTech Connect

    Jordan, S.A.; Feeley, M.M.

    1999-02-01

    As part of a multidisciplinary toxicological investigation into Great Lakes contaminants, chinook salmon were collected from lake Huron (LH) and Lake Ontario (LO) and incorporated into standard rat diets as 20 or 100% of the protein complement. Final PCB concentrations in the experiment ranged from 3.15 ng/g in the control diet to 1,080 ngg in the high-dose LO diet, with maximal estimated daily consumption by the rats of 82 {micro}g PCBs/kg body wt in the LO20 dietary group. Seventeen PCB congeners, PCB 85, 99, 101, 105, 110, 118, 128, 129, 132, 138, 149, 153, 170, 177, 180, 187, and 199, occurred at > 3.0% of the total PCBs in the fish with no major site differences. Cumulatively, these 17 congeners accounted for up to 75% of the total PCBs in the fish compared to 44 and 54% in two commercial Aroclors, 1254 and 1260, respectively. PCB 77 was the major dioxin-like congener in the fish, followed by PCB 126 and then PCB 169. All major dietary congeners bioaccumulated in the adipose tissue of the rats with the exception of PCB congeners 101, 110, 132, and 149.

  19. Fish consumption behavior and rates in native and non-native people in Saudi Arabia

    PubMed Central

    Burger, Joanna; Gochfeld, Michael; Batang, Zenon; Alikunhi, Nabeel; Al-Jahdali, Ramzi; Al-Jebreen, Dalal; Aziz, Mohammed A. M.; Al-Suwailem, Abdulaziz

    2015-01-01

    Fish are a healthy source of protein and nutrients, but contaminants in fish may provide health risks. Determining the risk from contaminants in fish requires site-specific information on consumption patterns. We examine consumption rates for resident and expatriates in the Jeddah region of Saudi Arabia, by species of fish and fishing location. For Saudis, 3.7 % of males and 4.3 % of females do not eat fish; for expatriates, the percent not eating fish is 6.6 % and 6.1 % respectively. Most people eat fish at home (over 90 %), and many eat fish at restaurants (65 % and 48 %, respectively for Saudis and expatriates). Fish eaten at home comes from local fish markets, followed by supermarkets. Saudis included fish in their diets at an average of 1.4±1.2 meals/week at home and 0.8±0.7 meals/week at restaurants, while expats ate 2.0±1.7 meals/week at home and 1.1±1.1 meals/week in restaurants. Overall, Saudis ate 2.2 fish meals/week, while expats ate 3.1 meals/week. Grouper (Epinephelus and Cephalopholis) were eaten by 72% and 60% respectively. Plectropomus pessuliferus was the second favorite for both groups and Hipposcarus harid and Lethrinus lentjan were in 3rd and 4th place in terms of consumption. Average meal size was 68 g for Saudis and 128 g for expatriates. These data can be used by health professionals, risk assessors, and environmental regulators to examine potential risk from contaminants in fish, and to compare consumption rates with other sites. PMID:24926920

  20. Patterns in Habitat and Fish Assemblages within Great Lakes Coastal Wetlands and Implications for Sampling Design

    EPA Science Inventory

    Discerning fish - habitat associations at a variety of spatial scales is relevant to evaluating stressor responses and assessment protocols in Great Lakes coastal wetlands. NMDS ordination of electrofishing catch-per-effort data identified an overriding influence of geography an...

  1. Fish community comparisons along environmental gradients in lakes of France and north-east USA

    EPA Science Inventory

    To assess whether eight traits of fish communities (species richness, three reproductive traits and four trophic traits) respond similarly to environmental gradients, and consequently display convergence between the lakes of France and north-east USA (NEUSA). Location 75 Frenc...

  2. Estimates of fish consumption rates for consumers of bought and self-caught fish in Connecticut, Florida, Minnesota, and North Dakota.

    PubMed

    Moya, Jacqueline; Itkin, Cheryl; Selevan, Sherry G; Rogers, John W; Clickner, Robert P

    2008-09-15

    Fish consumption rates derived from national surveys may not accurately reflect consumption rates in a particular population such as recreational anglers. Many state and local health agencies in the U.S. have conducted area-specific surveys to study fish consumption patterns in local populations, assess exposure to environmental contaminants, or evaluate compliance with fish advisories. The U.S. Environmental Protection Agency (EPA) has analyzed the raw data from fish consumption surveys in Florida, Connecticut, Minnesota, and North Dakota for the purpose of deriving distributions of fish consumption rates and studying the variables that may be more predictive of high-end consumers. Distributions of fish consumption for different age cohorts, ethnic groups, socioeconomic statuses, types of fish (i.e., freshwater, marine, estuarine), and source of fish (i.e., store-bought versus self-caught) were derived. Consumption of fish and shellfish for those who consume both caught and bought fish is higher than those who reported eating only bought or only self-caught. Mean fish consumption per kilogram of body weight ranged from 0.11 g/kg-day to 2.3 g/kg-day. The highest values were observed in Florida for children 1<6 years of age. The Florida data show a statistically significant increase in the percentage of the population reporting fish and shellfish consumption with an increase in household income and education. This trend was not observed in the other states.

  3. Fish consumption patterns and mercury exposure levels among women of childbearing age in Duval County, Florida.

    PubMed

    Traynor, Sharleen; Kearney, Greg; Olson, David; Hilliard, Aaron; Palcic, Jason; Pawlowicz, Marek

    2013-01-01

    Consumption of fish containing methylmercury can pose serious health concerns including neurotoxic effects in adults and toxicity to the fetuses of mothers exposed during pregnancy. In the study described in this article, the authors examined fish consumption patterns and measured hair mercury levels of women of childbearing age in a coastal county in Florida. Women from the community participated in a risk factor assessment survey (N = 703). Hair samples (n = 698) were collected and analyzed for mercury. The authors identified 74.8% below detection limit; 25.2% had detectable limits of mercury, while 7% exceeded 1 pg/g. Hair mercury levels increased with fish consumption and age. Race, income, and education levels were also associated with increased hair mercury levels. Women of Asian/Pacific Islander origin had the highest levels. Although reported fish consumption exceeded the recommendations for women of childbearing age, the study population had lower mercury levels than other comparative studies in Florida and at national levels.

  4. Omega-3 fatty acids and the benefits of fish consumption: is all that glitters gold?

    PubMed

    Domingo, José L

    2007-10-01

    In recent years, a number of studies have clearly remarked the nutritional benefits of fish consumption: proteins, vitamins, minerals, and especially omega-3 polyunsaturated fatty acids (PUFAs), which may protect against several adverse health effects, including coronary heart disease mortality and stroke. However, some concerns about potential health risks derived from the environmental contaminants found in fish have been also raised. Therefore, balancing adequately the risks and benefits of fish consumption is currently a nutritional/environmental health key issue. In this paper, the most recent available scientific information concerning this issue is reviewed. It is concluded that although it seems evident that fish must be an important part of a balanced diet, to choose the most suitable species in terms of levels of PUFAs and pollutants, the frequency of consumption, and the meal size are essential aspects to balance benefits and risks of a regular consumption.

  5. Adirondack lakes survey: An interpretive analysis of fish communities and water chemistry, 1984--1987

    SciTech Connect

    Baker, J.P. , Raleigh, NC ); Gherini, S.A.; Munson, R.K. ); Christensen, S.W. ); Driscoll, C.T. ); Gallagher, J. ); Newton, R.M. ); Reckhow, K.H. ); Schofield, C.L. (Co

    1990-01-01

    The Adirondack Lakes Survey Corporation (ALSC) was formed as a cooperative effort of the New York State Department of Environmental Conservation and the Empire State Electric Energy Research Corporation to better characterize the chemical and biological status of Adirondack lakes. Between 1984 and 1987, the ALSC surveyed 1469 lakes within the Adirondack ecological zone. As a follow-up to the survey, the ALSC sponsored a series of interpretive analyses of the ALSC data base. The primary objectives of these analyses were as follows: Evaluate the influence of mineral acids (from acidic deposition) and nonmineral acids (natural organic acids) on lake pH levels; classify Adirondack lakes according to lake and watershed features expected to influence their responsiveness to changes in acidic deposition; evaluate the sensitivity of Adirondack lakes to changes in environmental conditions, such as changes in mineral acids or dissolved organic carbon concentrations; identify lake characteristics important in explaining the observed present-day status of fish communities in Adirondack lakes, in particular the relative importance of lake acidity; evaluate changes that have occurred over time in Adirondack fish communities and probable causes for these trends by using the available historical data on fish communities in the Adirondacks and the ALSC data base; and determine the degree to which the existing fish resource might be at risk from continued acidic deposition, or might recover if acidity levels were reduced. The basic approach examined relationships observed in the ALSC data base among watershed characteristics, lake chemistry, and fish status. Individual reports are processed separately for the data bases.

  6. Contaminant residues in fish and sediments from lakes in the Atchafalaya River Basin (Louisiana)

    USGS Publications Warehouse

    Winger, P.V.; Andreasen, J.K.

    1985-01-01

    Conversion of bottomland hardwood forests agricultural land has reduced habitat and water quality in many lakes in the floodplain of the lower Mississippi River. The objectives of this study were to ascertain current contaminant residue concentrations in fish and sediment from lakes in the Atchafalaya River Basin and to determine the influence of overflow and agricultural land use on contaminant levels. Fish and sediment samples were collected from eight lakes that differed in overflow (no overflow, headwater overflow, backwater overflow) and land-use characteristics (presence or absence of agricultural land). Residue analysis of 24 sediment and 82 fish samples collected from the study lakes showed that contaminant residues were uniformly low. Total DDT concentrations, consisting mainly of DDE, were found in 98% of the fish samples and generally were the highest residues though they rarely exceeded 0.50 ug/g. Dieldrin, -BHC and -BHC, in concentrations rarely exceeding 0.05 ug/g, were detected in about 50% of the fish samples. Total organochlorine pesticide and PCB residues were less than 2.00 ug/g in all fish from all lakes, except for a 3.46 ug/g total in spotted gar (Lepisosteus oculatus) from one lake. Sediments were free from pesticide residues except for occasional traces (0.01 ug/g) of -BHC. Metal residue concentrations in fish and sediment samples were typical of uncontaminated areas. Lake systems in the Atchafalaya River Basin appeared to be relatively uncontaminated by agricultural pesticides, but metal and organic residues in fish were similar from lakes with the same land-use and overflow characteristics.

  7. Assessment of microcystins in lake water and fish (Mugilidae, Liza sp.) in the largest Spanish coastal lake.

    PubMed

    Romo, Susana; Fernández, Francisca; Ouahid, Youness; Barón-Sola, Ángel

    2012-01-01

    Cyanobacteria dominance and cyanotoxin production can become major threats to humans and aquatic life, especially in warm shallow lakes, which are often dominated by cyanobacteria. This study investigates the occurrence and distribution of microcystins (MCYST) in water, cell-bound and in the tissues of the commercial mugilid Liza sp. in the largest, coastal, Spanish Mediterranean lake (Albufera of Valencia). This is the first report concerning microcystin accumulation in tissues of mugilid fish species. Considerable amounts of microcystins were found in the water and seston, which correlated with development of Microcystis aeruginosa populations in the lake. The MCYST concentrations found in Lake Albufera (mean 1.7 and 17 μg/L and maximum 16 and 120 μg/L in water and seston, respectively) exceeded by one to two orders of magnitude the guideline levels proposed by the World Health Organization and were higher than that reported in other lakes of the Mediterranean zone. The presence of MCYST was found in all the fishes studied and accumulated differently among tissues of the commercial species Liza sp. Toxin accumulation in fish tissues showed that although the target organ for MCYST was the liver, high concentrations of microcystins were also found in other analysed tissues (liver>intestine>gills>muscle). Human tolerable daily intake for microcystins is assessed relative to the WHO guidelines, and potential toxicological risks for humans, wildlife and related ecosystems of the lake are discussed.

  8. Spatial patterns in assemblage structures of pelagic forage fish and zooplankton in western Lake Superior

    USGS Publications Warehouse

    Johnson, Timothy B.; Hoff, Michael H.; Trebitz, Anett S.; Bronte, Charles R.; Corry, Timothy D.; Kitchell, James F.; Lozano, Stephen J.; Mason, Doran M.; Scharold, Jill V.; Schram, Stephen T.; Schreiner, Donald R.

    2004-01-01

    We assessed abundance, size, and species composition of forage fish and zooplankton communities of western Lake Superior during August 1996 and July 1997. Data were analyzed for three ecoregions (Duluth-Superior, Apostle Islands, and the open lake) differing in bathymetry and limnological and biological patterns. Zooplankton abundance was three times higher in the Duluth-Superior and Apostle Islands regions than in the open lake due to the large numbers of rotifers. Copepods were far more abundant than Cladocera in all ecoregions. Mean zooplankton size was larger in the open lake due to dominance by large calanoid copepods although size of individual taxa was similar among ecoregions. Forage fish abundance and biomass was highest in the Apostle Islands region and lowest in the open lake ecoregion. Lake herring (Coregonus artedi), rainbow smelt (Osmerus mordax) and deepwater ciscoes (Coregonus spp.) comprised over 90% of the abundance and biomass of fishes caught in midwater trawls and recorded with hydroacoustics. Growth and condition of fish was good, suggesting they were not resource limited. Fish and zooplankton assemblages differed among the three ecoregions of western Lake Superior, due to a combination of physical and limnological factors related to bathymetry and landscape position.

  9. MERGANSER - An Empirical Model to Predict Fish and Loon Mercury in New England Lakes

    EPA Science Inventory

    MERGANSER (MERcury Geo-spatial AssessmeNtS for the New England Region) is an empirical least-squares multiple regression model using mercury (Hg) deposition and readily obtainable lake and watershed features to predict fish (fillet) and common loon (blood) Hg in New England lakes...

  10. Trophic connections in Lake Superior Part II: the nearshore fish community

    USGS Publications Warehouse

    Gamble, A.E.; Hrabik, T.R.; Yule, D.L.; Stockwell, J.D.

    2011-01-01

    We use detailed diet analyses of the predominant planktivorous, benthivorous and piscivorous fish species from Lake Superior to create a nearshore (bathymetric depths Mysis diluviana and Diporeia spp). Although the piscivorous fishes like lean lake trout (Salvelinus namaycush) fed to a lesser extent on Diporeia and Mysis, they were still strongly connected to these macroinvertebrates, which were consumed by their primary prey species (sculpin spp., rainbow smelt Osmerus mordax, and coregonines). The addition of Bythotrephes to summer/fall cisco and lake whitefish diets, and the decrease in rainbow smelt in lean lake trout diets (replaced by coregonines) were the largest observed differences relative to historic Lake Superior diet studies. Although the offshore food web of Lake Superior was simpler than nearshore in terms of number of fish species present, the two areas had remarkably similar food web structures, and both fish communities were primarily supported by Mysis and Diporeia. We conclude that declines in Mysis or Diporeia populations would have a significant impact on energy flow in Lake Superior. The food web information we generated can be used to better identify management strategies for Lake Superior.

  11. TOTAL AND METHYL MERCURY CONCENTRATIONS IN 1994-5 LAKE MICHIGAN FORAGE FISH

    EPA Science Inventory

    Forage fish samples were collected between 1194 and 1995 by the USGS Great Lakes Science Center in Ann Arbor, MI. Samples of bloater, slimy sculpin, deep water sculpin, alewife, and rainbow smelt were collected from regions of the lake near Saugatuck, MI and Port Washington and S...

  12. EPA Awards Great Lakes Restoration Initiative Grant to Clarkson University for Monitoring Pollutants in Fish

    EPA Pesticide Factsheets

    CHICAGO -- The U.S Environmental Protection Agency today announced that Clarkson University in Potsdam, New York, has received a $6.5 million Great Lakes Restoration Initiative grant to monitor pollutants in Great Lakes fish over the next five years. This

  13. MERCURY IN SEDIMENTS AND FISH FROM NORTH MISSISSIPPI LAKES AND SUBSEQUENT HUMAN HAZARD EVALUATION

    EPA Science Inventory

    Sediments and/or fish were collected from Sardis, Enid and Grenada Lakes, which are located in three different watersheds in North Mississippi, in order to assess mercury contamination. The mean total mercury concentration in sediments from Enid Lake in 1997 was 0.154 mg Hg/kg, w...

  14. Phylogenetic and ecological characteristics associated with thiaminase activity in Laurentian Great Lakes fishes

    USGS Publications Warehouse

    Riley, S.C.; Evans, A.N.

    2008-01-01

    Thiamine deficiency complex (TDC) causes mortality and sublethal effects in Great Lakes salmonines and results from low concentrations of egg thiamine that are thought to be caused by thiaminolytic enzymes (i.e., thiaminase) present in the diet. This complex has the potential to undermine efforts to restore lake trout Salvelinus namaycush and severely restrict salmonid production in the Great Lakes. Although thiaminase has been found in a variety of Great Lakes fishes, the ultimate source of thiaminase in Great Lakes fishes is currently unknown. We used logistic regression analysis to investigate relationships between thiaminase activity and phylogenetic or ecological characteristics of 39 Great Lakes fish species. The taxonomically more ancestral species were more likely to show thiaminase activity than the more derived species. Species that feed at lower trophic levels and occupy benthic habitats also appeared to be more likely to show thiaminase activity; these variables were correlated with taxonomy, which was the most important predictor of thiaminase activity. Further analyses of the relationship between quantitative measures of thiaminase activity and ecological characteristics of Great Lakes fish species would provide greater insight into potential sources and pathways of thiaminase in Great Lakes food webs. ?? Copyright by the American Fisheries Society 2008.

  15. Patterns of lake occupancy by fish indicate different adaptations to life in a harsh Arctic environment

    USGS Publications Warehouse

    Haynes, Trevor B.; Rosenberger, Amanda E.; Lindberg, Mark S.; Whitman, Matthew; Schmutz, Joel A.

    2014-01-01

    Based on these patterns, we propose an overall model of primary controls on the distribution of fish on the Arctic Coastal Plain of Alaska. Harsh conditions, including lake freezing, limit occupancy in winter through extinction events while lake occupancy in spring and summer is driven by directional migration (large-bodied species) and undirected dispersal (small-bodied species).

  16. Environmental Assessment: Lake Yankton Fish Population Renovation Project Yankton County, South Dakota and Cedar County, Nebraska

    DTIC Science & Technology

    2014-08-01

    mussels are known to exist in Lake Yankton. Western Prairie Fringed Orchid (Platanthera praeclara) No Affect. The western prairie fringed orchid is...a species of the North American tallgrass prairie community. Western prairie fringed orchid populations have declined significantly throughout... orchid habitat is known to occur near Lake Yankton. Lake Yankton Fish Population Renovation Project U.S. Army Corps of Engineers August 2014 3-11 Omaha

  17. Winter Fish Populations in Probable Locations of Air Bubblers in the St. Marys River-Lake Superior Area

    DTIC Science & Technology

    1980-09-01

    macrobenthos communities of St. Marys River, Lake Superior and Lake Huron ." 2. A reconnaissance trip in October 1979 was used to test sampling gear and...Marys River, Lake Superior and Lake Huron . D - cological Effects of Air bubblers in the Winter, a Partially Annotated Bibliography. Acoession For NTTS...8217 APPENDIX C Ar,’JOTATED BIBLIOGRAPHY ON WINTER FISH AND MACROBENTHOS COMMUNITIES OF ST. MARYS RIVER, LAKE SUPERIOR AND LAKE HURON ANNOTATED BIBLIOGRAPHY ON

  18. Population-structure and genetic diversity in a haplochromine cichlid fish [corrected] of a satellite lake of Lake Victoria.

    PubMed

    Abila, Romulus; Barluenga, Marta; Engelken, Johannes; Meyer, Axel; Salzburger, Walter

    2004-09-01

    The approximately 500 species of the cichlid fish species flock of Lake Victoria, East Africa, have evolved in a record-setting 100,000 years and represent one of the largest adaptive radiations. We examined the population structure of the endangered cichlid species Xystichromis phytophagus from Lake Kanyaboli, a satellite lake to Lake Victoria in the Kenyan Yala wetlands. Two sets of molecular markers were analysed--sequences of the mitochondrial control region as well as six microsatellite loci--and revealed surprisingly high levels of genetic variability in this species. Mitochondrial DNA sequences failed to detect population structuring among the three sample populations. A model-based population assignment test based on microsatellite data revealed that the three populations most probably aggregate into a larger panmictic population. However, values of population pairwise FST indicated moderate levels of genetic differentiation for one population. Eleven distinct mitochondrial haplotypes were found among 205 specimens of X. phytophagus, a relatively high number compared to the total number of 54 haplotypes that were recovered from hundreds of specimens of the entire cichlid species flock of Lake Victoria. Most of the X. phytophagus mitochondrial DNA haplotypes were absent from the main Lake Victoria, corroborating the putative importance of satellite lakes as refugia for haplochromine cichlids that went extinct from the main lake in the last decades and possibly during the Late Pleistocene desiccation of Lake Victoria.

  19. Exposure assessment for trace elements from consumption of marine fish in Southeast Asia.

    PubMed

    Agusa, Tetsuro; Kunito, Takashi; Sudaryanto, Agus; Monirith, In; Kan-Atireklap, Supawat; Iwata, Hisato; Ismail, Ahmad; Sanguansin, Joompol; Muchtar, Muswerry; Tana, Touch Seang; Tanabe, Shinsuke

    2007-02-01

    Concentrations of 20 trace elements were determined in muscle and liver of 34 species of marine fish collected from coastal areas of Cambodia, Indonesia, Malaysia and Thailand. Large regional difference was observed in the levels of trace elements in liver of one fish family (Carangidae): the highest mean concentration was observed in fish from the Malaysian coastal waters for V, Cr, Zn, Pb and Bi and those from the Java Sea side of Indonesia for Sn and Hg. To assess the health risk to the Southeast Asian populations from consumption of fish, intake rates of trace elements were estimated. Some marine fish showed Hg levels higher than the guideline values by U.S. Environmental Protection Agency and Joint FAO/WHO Expert Committee on Food Additives (JECFA). This suggests that consumption of these fish may be hazardous to the people.

  20. Projected shifts in fish species dominance in Wisconsin lakes under climate change.

    PubMed

    Hansen, Gretchen J A; Read, Jordan S; Hansen, Jonathan F; Winslow, Luke A

    2017-04-01

    Temperate lakes may contain both coolwater fish species such as walleye (Sander vitreus) and warmwater fish species such as largemouth bass (Micropterus salmoides). Recent declining walleye and increasing largemouth bass populations have raised questions regarding the future trajectories and management actions for these species. We developed a thermodynamic model of water temperatures driven by downscaled climate data and lake-specific characteristics to estimate daily water temperature profiles for 2148 lakes in Wisconsin, US, under contemporary (1989-2014) and future (2040-2064 and 2065-2089) conditions. We correlated contemporary walleye recruitment and largemouth bass relative abundance to modeled water temperature, lake morphometry, and lake productivity, and projected lake-specific changes in each species under future climate conditions. Walleye recruitment success was negatively related and largemouth bass abundance was positively related to water temperature degree days. Both species exhibited a threshold response at the same degree day value, albeit in opposite directions. Degree days were predicted to increase in the future, although the magnitude of increase varied among lakes, time periods, and global circulation models (GCMs). Under future conditions, we predicted a loss of walleye recruitment in 33-75% of lakes where recruitment is currently supported and a 27-60% increase in the number of lakes suitable for high largemouth bass abundance. The percentage of lakes capable of supporting abundant largemouth bass but failed walleye recruitment was predicted to increase from 58% in contemporary conditions to 86% by mid-century and to 91% of lakes by late century, based on median projections across GCMs. Conversely, the percentage of lakes with successful walleye recruitment and low largemouth bass abundance was predicted to decline from 9% of lakes in contemporary conditions to only 1% of lakes in both future periods. Importantly, we identify up to 85

  1. Status and historical changes in the fish community in Erhai Lake

    NASA Astrophysics Data System (ADS)

    Tang, Jianfeng; Ye, Shaowen; Li, Wei; Liu, Jiashou; Zhang, Tanglin; Guo, Zhiqiang; Zhu, Fengyue; Li, Zhongjie

    2013-07-01

    Erhai Lake is the second largest freshwater lake on the Yunnan Plateau, Southwest China. In recent decades, a number of exotic fish species have been introduced into the lake and the fish community has changed considerably. We evaluated the status of the fish community based on surveys with multimesh gillnet, trap net, and benthic fyke-net between May 2009 and April 2012. In addition, we evaluated the change in the community using historical data (1952-2010) describing the fish community and fishery harvest. The current fish community is dominated by small-sized fishes, including Pseudorasbora parva, Rhinogobius giurinus, Micropercops swinhonis, Hemiculter leucisculus, and Rhinogobius cliffordpopei. These accounted for 87.7% of the 22 546 total specimens collected. Omnivorous and carnivorous species dominated the community. A canonical correspondence analysis (CCA) plot revealed that the distribution of fishes in the lake is influenced by aquatic plants, water temperature, pH, and season. The abundance of indigenous species has declined sharply, and a majority of endemic species have been extirpated from the lake (a decrease from seven to two species). In contrast, the number of exotic species has increased since the 1960s to a total of 22 at present. The fishery harvest decreased initially following the 1960s, but has since increased due to the introduction of non-native fish and stocking of native fish. The fishery harvest was significantly correlated with total nitrogen, not total phosphorus, during the past 20 years. Based on our results, we discuss recommendations for the restoration and conservation of the fish resources in Erhai Lake.

  2. Sport fish consumption and body burden levels of chlorinated hydrocarbons: a study of Wisconsin anglers

    SciTech Connect

    Fiore, B.J.; Anderson, H.A.; Hanrahan, L.P.; Olson, L.J.; Sonzogni, W.C.

    1989-03-01

    Sport-caught fish consumption is the major source of polychlorinated biphenyls (PCBs) exposure for the general population. To assess this and 2,2'-bis-(p-chlorophenyl)-1,1-dichloroethylene (DDE) exposure, we surveyed 801 Wisconsin anglers for fishing and consumption habits and comprehension of and compliance with the Wisconsin fish consumption health advisory. The mean annual number of sport-caught fish meals was 18. Seventy-two percent of anglers were familiar with the health advisory and 57% had changed their fishing or fish consumption habits as a result of the advisory. The mean PCB serum congener sum level for 192 anglers was 2.2 micrograms/l (range = nondetectable to 27.1 micrograms/l); mean DDE was 6.3 micrograms/l (range = nondetectable to 40.0 micrograms/l). Statistically significant positive Spearman correlations were observed between sport-caught fish meals and PCB and DDE sera levels (R = .21 and .14, respectively) and between kilograms of fish caught and PCB sera levels (R = .25). These results demonstrate that anglers may provide a population for assessment of PCBs and DDE associated morbidity and mortality.

  3. SIMULATION AND VALIDATION OF FISH THERMAL DO HABITAT IN NORTH-CENTRAL US LAKES UNDER DIFFERENT CLIMATE SCENARIOS. (R824801)

    EPA Science Inventory

    Abstract

    Fish habitat in lakes is strongly constrained by water temperature and available dissolved oxygen (DO). Suitable fish habitat for three fish assemblages (cold-, cool-, and warm-water) in Minnesota (US) lakes was therefore determined from simulated daily water ...

  4. Fish assemblages in oxbow lakes relative to connectivity with the Mississippi River

    USGS Publications Warehouse

    Miranda, L.E.

    2005-01-01

    The alluvial valley of the lower Mississippi River contains hundreds of fluvial lakes that are periodically connected to the river during high water, although the frequency, duration, and timing of the connections vary. To help design plans to restore and preserve fish assemblages in these alluvial lakes, this investigation tested whether predictable patterns in lake fish assemblages were linked to the level of connectivity with the river. Results suggested that connectivity played an important role in structuring fish assemblages and that it was correlated with variables such as lake size, depth, distance from the river, and age, which exhibit a continuum of predictable features as the river migrates away from abandoned channels. Annual floods homogenize the floodplain and promote connectivity to various degrees, allowing for fish exchanges between river and floodplain that directly affect fish assemblages. The major physical changes linked to reduced connectivity are loss of depth and area, which in turn affect a multiplicity of abiotic and biotic features that indirectly affect community structure. In advanced stages of disconnection, fish assemblages in oxbow lakes are expected to include largely species that thrive in turbid, shallow systems with few predators and low oxygen content. When the river flowed without artificial restraint, oxbow lakes were created at the rate of 13-15 per century. At present, no or few oxbow lakes are being formed, and as existing lakes age, they are becoming shallower, smaller, and progressively more disconnected from the river. Given that modifications to the Mississippi River appear to be irreversible, conservation of this resource requires maintenance of existing lakes at a wide range of aging phases that provide diverse habitats and harbor distinct species assemblages.

  5. A Holocene paleomagnetic record from Fish Lake, Oregon.

    NASA Astrophysics Data System (ADS)

    Ziegler, L. B.; Stoner, J. S.; Abbott, M. B.; Finkenbinder, M. S.; Hatfield, R. G.; Konyndyk, D.; Reilly, B.; Hillman, A. L.

    2014-12-01

    Paleo-geomagnetic observations provide fundamental models of the core and the geodynamo that cannot other- wise be obtained. Data and modeling studies are beginning to show that regions of concentrated magnetic flux (flux lobes) on the Core-Mantle boundary, those observed historically and others only hinted at from the short historical record, impose a structure on the geomagnetic field that may govern at least some components of geo- magnetic change. Accumulating evidence suggests that this structure reflects the influence of the lower mantle, yet this structure and the evolution of the geomagnetic field within it, even for the Holocene, are only beginning to be- come apparent. Comparison of specific, well-dated Holocene timeseries of PSV (sedimentary and archeomagnetic) inclination, declination, and paleointensity at key locations can provide intriguing insight when viewed through the lens of the known historical and assumed millennial flux lobes. A limiting factor for these studies is the uneven distribution of high quality data with independent chronologies, with Europe and the North Atlantic having better constrained data sets than North America. To begin to fill this data gap, we present initial results from an ongoing study of the paleomagnetic record from Fish Lake, Oregon. Initial evaluation of directions and intensity along with the construction of an independent chronology allow us to assess and build upon prior results to constrain the evolution of the North American flux lobe and refine our understanding of paleo-geomagnetic change during the Holocene.

  6. Biomagnification of DDT and its metabolites in four fish species of a tropical lake.

    PubMed

    Deribe, Ermias; Rosseland, Bjørn Olav; Borgstrøm, Reidar; Salbu, Brit; Gebremariam, Zinabu; Dadebo, Elias; Skipperud, Lindis; Eklo, Ole Martin

    2013-09-01

    The concentrations and biomagnifications of dichlorodiphenyltrichloroethane (DDT) and its metabolites were examined in four fish species (Clarias gariepinus, Oreochromis niloticus, Tilapia zillii, and Carassius auratus) from Lake Ziway, Rift Valley, Ethiopia. Paired stomach content analysis, and stable isotope ratio of nitrogen (δ(15)N, ‰) and carbon (δ(13)C, ‰) were used to study the trophic position of the fish species in the lake. 4,4'-DDE, 4,4'-DDT and 4,4'-DDD were the main DDTs identified in the fish samples, with 4,4'-DDE as the most predominant metabolite, with mean concentration ranging from 1.4 to 17.8 ng g(-1) wet weight (ww). The concentrations of DDTs found in fish from Lake Ziway were, in general lower than those found in most studies carried out in other African Lakes. However, the presence of DDT in all tissue samples collected from all fish species in the lake indicates the magnitude of the incidence. Moreover, the observed mean 4,4'-DDE to 4,4'-DDT ratio below 1 in C. auratus from Lake Ziway may suggest a recent exposure of these species to DDT, indicating that a contamination source is still present. 4,4'-DDE was found to biomagnify in the fish species of the lake, and increases with trophic level, however, the biomagnification rate was generally lower than what has been reported from other areas. Significantly higher concentrations of 4,4'-DDE were found in the top consumer fish in Lake Ziway, C. gariepinus than in O. niloticus (t=2.6, P<0.01), T. zillii (t=2.5, P<0.02) and C. auratus (t=2.2, P<0.03).

  7. Response of fish assemblages to declining acidic deposition in Adirondack Mountain lakes, 1984-2012

    NASA Astrophysics Data System (ADS)

    Baldigo, B. P.; Roy, K. M.; Driscoll, C. T.

    2016-12-01

    Adverse effects of acidic deposition on the chemistry and fish communities were evident in Adirondack Mountain lakes during the 1980s and 1990s. Fish assemblages and water chemistry in 43 Adirondack Long-Term Monitoring (ALTM) lakes were sampled by the Adirondack Lakes Survey Corporation and the New York State Department of Environmental Conservation during three periods (1984-87, 1994-2005, and 2008-12) to document regional impacts and potential biological recovery associated with the 1990 amendments to the 1963 Clean Air Act (CAA). We assessed standardized data from 43 lakes sampled during the three periods to quantify the response of fish-community richness, total fish abundance, and brook trout (Salvelinus fontinalis) abundance to declining acidity that resulted from changes in U.S. air-quality management between 1984 and 2012. During the 28-year period, mean acid neutralizing capacity (ANC) increased significantly from 3 to 30 μeq/L and mean inorganic monomeric Al concentrations decreased significantly from 2.22 to 0.66 μmol/L, yet mean species richness, all species or total catch per net night (CPNN), and brook trout CPNN did not change significantly in the 43 lakes. Regression analyses indicate that fishery metrics were not directly related to the degree of chemical recovery and that brook trout CPNN may actually have declined with increasing ANC. While the richness of fish communities increased with increasing ANC as anticipated in several Adirondack lakes, observed improvements in water quality associated with the CAA have generally failed to produce detectable shifts in fish assemblages within a large number of ALTM lakes. Additional time may simply be needed for biological recovery to progress, or else more proactive efforts may be necessary to restore natural fish assemblages in Adirondack lakes in which water chemistry is steadily recovering from acidification.

  8. Response of fish assemblages to declining acidic deposition in Adirondack Mountain lakes, 1984–2012

    USGS Publications Warehouse

    Baldigo, Barry P.; Roy, Karen; Driscoll, Charles T.

    2016-01-01

    Adverse effects of acidic deposition on the chemistry and fish communities were evident in Adirondack Mountain lakes during the 1980s and 1990s. Fish assemblages and water chemistry in 43 Adirondack Long-Term Monitoring (ALTM) lakes were sampled by the Adirondack Lakes Survey Corporation and the New York State Department of Environmental Conservation during three periods (1984–87, 1994–2005, and 2008–12) to document regional impacts and potential biological recovery associated with the 1990 amendments to the 1963 Clean Air Act (CAA). We assessed standardized data from 43 lakes sampled during the three periods to quantify the response of fish-community richness, total fish abundance, and brook trout (Salvelinus fontinalis) abundance to declining acidity that resulted from changes in U.S. air-quality management between 1984 and 2012. During the 28-year period, mean acid neutralizing capacity (ANC) increased significantly from 3 to 30 μeq/L and mean inorganic monomeric Al concentrations decreased significantly from 2.22 to 0.66 μmol/L, yet mean species richness, all species or total catch per net night (CPNN), and brook trout CPNN did not change significantly in the 43 lakes. Regression analyses indicate that fishery metrics were not directly related to the degree of chemical recovery and that brook trout CPNN may actually have declined with increasing ANC. While the richness of fish communities increased with increasing ANC as anticipated in several Adirondack lakes, observed improvements in water quality associated with the CAA have generally failed to produce detectable shifts in fish assemblages within a large number of ALTM lakes. Additional time may simply be needed for biological recovery to progress, or else more proactive efforts may be necessary to restore natural fish assemblages in Adirondack lakes in which water chemistry is steadily recovering from acidification.

  9. A quantitative analysis of fish consumption and coronary heart disease mortality.

    PubMed

    König, Ariane; Bouzan, Colleen; Cohen, Joshua T; Connor, William E; Kris-Etherton, Penny M; Gray, George M; Lawrence, Robert S; Savitz, David A; Teutsch, Steven M

    2005-11-01

    Although a rich source of n-3 polyunsaturated fatty acids (PUFAs) that may confer multiple health benefits, some fish contain methyl mercury (MeHg), which may harm the developing fetus. U.S. government recommendations for women of childbearing age are to modify consumption of high-MeHg fish to reduce MeHg exposure, while recommendations encourage fish consumption among the general population because of the nutritional benefits. The Harvard Center for Risk Analysis convened an expert panel (see acknowledgements) to quantify the net impact of resulting hypothetical changes in fish consumption across the population. This paper estimates the impact of fish consumption on coronary heart disease (CHD) mortality and nonfatal myocardial infarction (MI). Other papers quantify stroke risk and the impacts of both prenatal MeHg exposure and maternal intake of n-3 PUFAs on cognitive development. This analysis identified articles in a recent qualitative review appropriate for the development of a dose-response relationship. Studies had to satisfy quality criteria, quantify fish intake, and report the precision of the relative risk estimates. Relative risk results were averaged, weighted proportionately by precision. CHD risks associated with MeHg exposure were reviewed qualitatively because the available literature was judged inadequate for quantitative analysis. Eight studies were identified (29 exposure groups). Our analysis estimated that consuming small quantities of fish is associated with a 17% reduction in CHD mortality risk, with each additional serving per week associated with a further reduction in this risk of 3.9%. Small quantities of fish consumption were associated with risk reductions in nonfatal MI risk by 27%, but additional fish consumption conferred no incremental benefits.

  10. Fish consumption and polyunsaturated fatty acids in relation to psychological distress

    PubMed Central

    Suominen-Taipale, Anna Liisa; Turunen, Anu W; Partonen, Timo; Kaprio, Jaakko; Männistö, Satu; Montonen, Jukka; Jula, Antti; Tiittanen, Pekka; Verkasalo, Pia K

    2010-01-01

    Background It has been suggested that high fish consumption improves mental well-being. The aim of this study was to assess whether high fish consumption or omega-3 polyunsaturated fatty acid (PUFA) intake was associated with reduced self-reported psychological distress. Methods We used three cross-sectional data sets, the nationwide Health 2000 Survey (n = 5840), the Fishermen Study on Finnish fishermen and their family members (n = 1282) and the Finntwin16 Study on young adults (n = 4986). Data were based on self-administered questionnaires, interviews, health examinations and blood samples. Psychological distress was measured using the 12-item and 21-item General Health Questionnaires (GHQs). Fish consumption was measured by a food frequency questionnaire (FFQ, g/day) and independent frequency questions (times/month). Dietary intake (g/day) and serum concentrations (% from fatty acids) of PUFAs were determined. Relationships were analysed using regression analysis. Results Regardless of the measure, fish consumption and omega-3 PUFA dietary intake were not associated with distress in any of the data sets. In contrast to the hypothesis, high serum docosahexaenoic acid was associated with high distress in the Fisherman Study men. Some non-linear associations were detected between serum omega-3 PUFAs or fish consumption (times/month) and distress. In the Fishermen Study, the associations were modified by alcohol consumption, smoking and physical activity. Conclusions Our results do not support the hypothesis that fish consumption or omega-3 PUFA intake are associated with reduced psychological distress in the general population or in a population with high fish consumption. PMID:20156998

  11. Surface water connectivity drives richness and composition of Arctic lake fish assemblages

    USGS Publications Warehouse

    Laske, Sarah M.; Haynes, Trevor B.; Rosenberger, Amanda E.; Koch, Joshua C.; Wipfli, Mark S.; Whitman, Matthew; Zimmerman, Christian E.

    2016-01-01

    This work provides useful baseline information on the processes that drive the relations between patch connectivity and fish species richness and assemblage composition. The environmental processes that organise fish assemblages in Arctic lakes are likely to change in a warming climate.

  12. Isolation and characterization of Flavobacterium columnare strains infecting fishes inhabiting the Laurentian Great Lakes basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavobacterium columnare, the etiological agent of columnaris disease, causes significant losses in fish worldwide. In this study, F. columnare infection prevalence was assessed in representative Great Lakes fish species. Over 2,000 wild, feral, and hatchery-propagated salmonids, percids, centrarc...

  13. Limnology and fish ecology of sockeye salmon nursery lakes of the world

    USGS Publications Warehouse

    Hartman, Wilbur L.; Burgner, R.L.

    1972-01-01

    Many important, recently glaciated oligotrophic lakes that lie in coastal regions around the northern rim of the Pacific Ocean produce anadromous populations of sockeye salmon, Oncorhynchus nerka. This paper describes the limnology and fish ecology of two such lakes in British Columbia, five in Alaska, and one in Kamchatka. Then we discuss the following general topics: the biogenic eutrophication of nursery lakes from the nutrients released from salmon carcasses wherein during years of highest numbers of spawners, lake phosphate balances in Lakes Babine, Iliamna, and Dalnee are significantly affected; the use of nursery lakes by young sockeye that reveals five patterns related to size and configuration of lake basins and the distribution of spawning areas; the interactions between various life history stages of sockeye salmon and such resident predators, competitors, and prey as Arctic char, lake trout, Dolly Varden, cutthroat trout, lake whitefish, pygmy whitefish, pond smelt, sticklebacks, and sculpins; the self-regulation of sockeye salmon abundance in these nursery lakes as controlled by density-dependent processes; the interrelations between young sockeye salmon biomass and growth rates, and zooplankton abundance in Babine Lake; and finally, the diel, vertical, pelagial migratory behavior of young sockeye in Babine Lake and the new hypothesis dealing with bioenergetic conservation.

  14. Fish body burden: An index of atmospheric deposition of contaminants in the Great Lakes Basin

    SciTech Connect

    Swain, W.R.

    1994-12-31

    Since the mid-1970`s, contaminant monitoring in the flesh of fish from Siskiwit Lake, a remote lake on Isle Royale (Lake Superior), has served as an index of atmospheric transport to the upper Great Lakes basin. Using contemporary analytic methodologies, analysis of historic archived samples from this lake when compared with 1993 collections indicate dramatic changes in contaminant burdens for many compounds of concern. For example, dieldrin, the alpha isomer of BHC, and DDT/DDD/DDE all increased between 1974--76 and 1980, but had decreased markedly by 1993. Chlordane (analyzed as technical, alpha, and gamma chlordane), and total PCBs demonstrated a steady decline from the mid 1 970`s to the present. The pattern for these compounds remains similar in both the contaminant burden data, and when the values are adjusted for fish lipid content. Congener specific analysis for toxic coplanar PCBs indicate that ten non or mono-ortho PCBs predominate in fish, six of which were observed in a remarkably consistent pattern and percentage composition, i.e., PCB 118 > 105 > 156 > 189 > 77. Polychlorinated dioxin (PCDD) and debenzofuran (PCDF) TEQ values also declined by half between 1980 and 1993. However, fish from a comparative atmospherically driven system, Crystal Lake, had PCDD and PCDF TEQs an order of magnitude below those of Isle Royale fish. These differences, along with the pattern of chlorination observed, suggest the possibility of relatively more local influences than the long range atmospheric transport which was originally implicated.

  15. Fish assemblages, connectivity, and habitat rehabilitation in a diked Great Lakes coastal wetland complex

    USGS Publications Warehouse

    Kowalski, Kurt P.; Wiley, Michael J.; Wilcox, Douglas A.

    2014-01-01

    Fish and plant assemblages in the highly modified Crane Creek coastal wetland complex of Lake Erie were sampled to characterize their spatial and seasonal patterns and to examine the implications of the hydrologic connection of diked wetland units to Lake Erie. Fyke netting captured 52 species and an abundance of fish in the Lake Erie–connected wetlands, but fewer than half of those species and much lower numbers and total masses of fish were captured in diked wetland units. Although all wetland units were immediately adjacent to Lake Erie, there were also pronounced differences in water quality and wetland vegetation between the hydrologically isolated and lake-connected wetlands. Large seasonal variations in fish assemblage composition and biomass were observed in connected wetland units but not in disconnected units. Reestablishment of hydrologic connectivity in diked wetland units would allow coastal Lake Erie fish to use these vegetated habitats seasonally, although connectivity does appear to pose some risks, such as the expansion of invasive plants and localized reductions in water quality. Periodic isolation and drawdown of the diked units could still be used to mimic intermediate levels of disturbance and manage invasive wetland vegetation.

  16. Acute toxicities to larval rainbow trout of representative compounds detected in Great Lakes fish

    USGS Publications Warehouse

    Edsall, Carol Cotant

    1991-01-01

    In recent years the National Fisheries Research Center-Great Lakes has ranked the potential hazard to fish and invertebrates of various chemical compounds detected in two Great Lakes fishes-- lake trout, Salvelinus namaycush, and walleye, Stizostedion vitreum vitreum (Hesselberg and Seelye 1982). This hazard assessment has included the identification of the potential sources of the compounds, determination of the occurrence and abundance of the compounds in Great Lakes fish, and the determination of acute toxicities of representative compounds of 19 chemical classes (Passino and Smith 1987a). In further studies Smith et al. (1988) focused on 6 of the 19 classes of compounds using the zooplankter Daphnia pulex as the test organism. They ranked the six classes as follows (in decreasing order of toxicity): polycyclic aromatic hydrocarbons (PAHs), alkyl halides, nitrogen-containing compounds, cyclic alkanes, heterocyclic nitrogen compounds, and silicon-containing compounds.

  17. Fish consumption and the risk of gastric cancer: systematic review and meta-analysis

    PubMed Central

    2011-01-01

    Background Gastric cancer is the fourth most frequently occurring malignancy after lung, breast, and colorectal cancer, and the second most common cause of death from cancer worldwide. Epidemiologic studies have examined the possible association between fish consumption and gastric cancer, but the results were inconclusive. We conducted a systematic review and meta-analysis to examine the association between fish intake and the risk of gastric cancer. Methods PubMed was searched for studies published in English-language journals from 1991 through 2009. We identified 17 epidemiologic studies (15 case-control and 2 cohort studies) that included relative risks (RRs) or odds ratios (ORs) estimates with 95% confidence intervals (CIs) of the relationship between gastric cancer and fish consumption. Data were extracted using standardized data forms. Summary RRs or ORs for the highest versus non/lowest fish consumption levels were calculated using random-effects model. Heterogeneity among studies was examined using Q and I2 statistics. Results In this study, 5,323 cases of gastric cancer and over 130,000 non-cases were included. The combined results from all studies indicated that the association between high fish consumption and reduced gastric cancer risk was not statistically insignificant (RR = 0.87, 95% CI = 0.71-1.07). Conclusions Current evidence indicated that the association between fish consumption and risk of gastric cancer remains unclear. PMID:21247502

  18. An empirical model for estimating annual consumption by freshwater fish populations

    USGS Publications Warehouse

    Liao, H.; Pierce, C.L.; Larscheid, J.G.

    2005-01-01

    Population consumption is an important process linking predator populations to their prey resources. Simple tools are needed to enable fisheries managers to estimate population consumption. We assembled 74 individual estimates of annual consumption by freshwater fish populations and their mean annual population size, 41 of which also included estimates of mean annual biomass. The data set included 14 freshwater fish species from 10 different bodies of water. From this data set we developed two simple linear regression models predicting annual population consumption. Log-transformed population size explained 94% of the variation in log-transformed annual population consumption. Log-transformed biomass explained 98% of the variation in log-transformed annual population consumption. We quantified the accuracy of our regressions and three alternative consumption models as the mean percent difference from observed (bioenergetics-derived) estimates in a test data set. Predictions from our population-size regression matched observed consumption estimates poorly (mean percent difference = 222%). Predictions from our biomass regression matched observed consumption reasonably well (mean percent difference = 24%). The biomass regression was superior to an alternative model, similar in complexity, and comparable to two alternative models that were more complex and difficult to apply. Our biomass regression model, log10(consumption) = 0.5442 + 0.9962??log10(biomass), will be a useful tool for fishery managers, enabling them to make reasonably accurate annual population consumption predictions from mean annual biomass estimates. ?? Copyright by the American Fisheries Society 2005.

  19. Metal bioavailability and toxicity to fish in low-alkalinity lakes - a critical-review

    USGS Publications Warehouse

    Spry, D.J.; Wiener, J.G.

    1991-01-01

    Fish in low-alkalinity lakes having ph of 6.0-6.5 Or less often have higher body or tissue burdens of mercury, cadmium, and lead than do fish in nearby lakes with higher ph. The greater bioaccumulation of these metals in such waters seems to result partly from the greater aqueous abundances of biologically available forms (ch3hg+, cd2+, and pb2+) at low ph. In addition, the low concentrations of aqueous calcium in low-alkalinity lakes increase the permeability of biological membranes to these metals, which in fish may cause greater uptake from both water and food. Fish exposed to aqueous inorganic aluminum in the laboratory and field accumulate the metal in and on the epithelial cells of the gills; however, there is little accumulation of aluminum in the blood or internal organs. In low-ph water, both sublethal and lethal toxicity of aluminum has been clearly demonstrated in both laboratory and field studies at environmental concentrations. In contrast, recently measured aqueous concentrations of total mercury, methylmercury, cadmium, and lead in low-alkalinity lakes are much lower than the aqueous concentrations known to cause acute or chronic toxicity in fish, although the vast majority of toxicological research has involved waters with much higher ionic strength than that in low-alkalinity lakes. Additional work with fish is needed to better assess (1) the toxicity of aqueous metals in low-alkalinity waters, and (2) the toxicological significance of dietary methylmercury and cadmium.

  20. Physiological refugia: swamps, hypoxia tolerance and maintenance of fish diversity in the Lake Victoria region.

    PubMed

    Chapman, Lauren J; Chapman, Colin A; Nordlie, Frank G; Rosenberger, Amanda E

    2002-11-01

    In Lake Nabugabo, Uganda, a satellite of Lake Victoria, approximately 50% of the indigenous fishes disappeared from the open waters subsequent to the establishment of the introduced predatory Nile perch, Lates niloticus. This pattern is similar to the faunal loss experienced in the much larger Lake Victoria. Several of these species persisted in wetland refugia (e.g. ecotonal wetlands, swamp lagoons); however, deep swamp refugia (habitats lying well within the dense interior of fringing wetlands), are available only to a subset of the basin fauna with extreme tolerance to hypoxia. Although air-breathers are common in deep swamp refugia; we also documented a surprisingly high richness and abundance of non-air-breathing fishes. We describe several mechanisms that may facilitate survival in deep swamp refugia including high hemoglobin concentration, high hematocrit, large gill surface area and a low critical oxygen tension (P(c)). In addition, swamp-dwelling fishes showed lower PO(2) thresholds for onset of aquatic surface respiration than the lake-dwelling fishes. This suggests higher tolerance to hypoxia in the swamp fishes because they are able to withstand a lower oxygen tension before approaching the surface. We suggest that physiological refugia may be important in modulating the impact of Nile perch and indigenous fishes in the Lake Nabugabo region; this highlights the need to evaluate relative tolerance of introduced predators and indigenous prey to environmental stressors.

  1. Lake morphometry and resource polymorphism determine niche segregation between cool- and cold-water-adapted fish.

    PubMed

    Hayden, Brian; Harrod, Chris; Kahilaineni, Kimmo K

    2014-02-01

    Climate change is increasing ambient temperatures in Arctic and subarctic regions, facilitating latitudinal range expansions of freshwater fishes adapted to warmer water temperatures. The relative roles of resource availability and interspecific interactions between resident and invading species in determining the outcomes of such expansions has not been adequately evaluated. Ecological interactions between a cool-water adapted fish, the perch (Perca fluviatilis), and the cold-water adapted European whitefish (Coregonus lavaretus), were studied in both shallow and deep lakes with fish communities dominated by (1) monomorphic whitefish, (2) monomorphic whitefish and perch, and (3) polymorphic whitefish and perch. A combination of stomach content, stable-isotope, and invertebrate prey availability data were used to identify resource use and niche overlap among perch, the trophic generalist large sparsely rakered (LSR) whitefish morph, and the pelagic specialist densely rakered (DR) whitefish morph in 10 subarctic lakes at the contemporary distribution limit of perch in northern Scandinavia. Perch utilized its putative preferred littoral niche in all lakes. LSR whitefish utilized both littoral and pelagic resources in monomorphic whitefish-dominated lakes. When found in sympatry with perch, LSR whitefish exclusively utilized pelagic prey in deep lakes, but displayed niche overlap with perch in shallow littoral lakes. DR whitefish was a specialist zooplanktivore, relegating LSR whitefish from pelagic habitats, leading to an increase in niche overlap between LSR whitefish and perch in deep lakes. Our results highlight how resource availability (lake depth and fish community) governs ecological interactions between native and invading species, leading to different outcomes even at the same latitudes. These findings suggest that lake morphometry and fish community structure data should be included in bioclimate envelope-based models of species distribution shifts

  2. Effects of introduced fishes on wild juvenile coho salmon in three shallow pacific northwest lakes

    USGS Publications Warehouse

    Bonar, Scott A.; Bolding, B.D.; Divens, M.; Meyer, W.

    2005-01-01

    Declines in Pacific salmon Oncorhynchus spp. have been blamed on hydropower, overfishing, ocean conditions, and land use practices; however, less is known about the impacts of introduced fish. Most of the hundreds of lakes and ponds in the Pacific Northwest contain introduced fishes, and many of these water bodies are also important for salmon production, especially of coho salmon O. kisutch. Over 2 years, we examined the predation impacts of 10 common introduced fishes (brown bullhead Ameiurus nebulosus, black crappie Pomoxis nigro-maculatus, bluegill Lepomis macrochirus, golden shiner Notemigonus crysoleucas, green sunfish L. cyanellus, largemouth bass Micropterus salmoides, pumpkinseed L. gibbosus, rainbow trout O. mykiss, warmouth L. gulosus, and yellow perch Perca flavescens) and two native fishes (cutthroat trout O. clarkii and prickly sculpin Cottus asper) on wild juvenile coho salmon in three shallow Pacific Northwest lakes, all located in different watersheds. Of these species, largemouth bass were responsible for an average of 98% of the predation on coho salmon in all lakes, but the total impact to each run varied among lakes and years. Very few coho salmon were eaten by black crappies, brown bullheads, cutthroat trout, prickly sculpin, or yellow perch, whereas other species were not observed to eat coho salmon. Juvenile coho salmon growth in all lakes was higher than in nearby streams. Therefore, food competition between coho salmon and introduced fishes in lakes was probably not limiting coho salmon populations. Largemouth bass are widespread and are present in 85% of lowland warmwater public-access lakes in Washington (n = 421), 84% of those in Oregon (n = 179), and 74% of those in the eight northwesternmost counties in California (n = 19). Future research would help to identify the impact of largemouth bass predation across the region and prioritize lakes where impacts are most severe. Nevertheless, attempts to transplant or increase largemouth bass

  3. Lake Michigan: Man's effects on native fish stocks and other biota

    USGS Publications Warehouse

    Wells, LaRue; McLain, Alberton L.

    1973-01-01

    Exploitation was largely responsible for the changes in Lake Michigan fish stocks before the invasion of the smelt, and probably before the invasion of the sea lamprey. The lamprey and alewife, however, have exerted a greater impact than the fishery on native fish populations in recent decades. Accelerated eutrophication and other pollution, although important, have not equalled the other factors in causing changes in native fish populations.

  4. Old fish in a young lake: stone loach (Pisces: Barbatula barbatula) populations in Lake Constance are genetically isolated by distance.

    PubMed

    Barluenga, Marta; Meyer, Axel

    2005-04-01

    The genetic structure of 10 populations (453 individuals) of stone loach (Barbatula barbatula L.), a small bottom-dwelling cyprinid fish, in the littoral zone of Lake Constance, central Europe, was investigated by analysing the mitochondrial control region sequences and five microsatellite loci. An unexpectedly high degree of genetic diversity (up to 0.36%) and old estimated age of these populations (> 150 000 years) based on mitochondrial DNA (mtDNA) was found. These findings contrast with the relatively young age of the lake, which could be colonized by fish only after the last ice age around 15 000 bp. Stone loach appears to be an old species in a young lake. Both types of molecular markers showed population genetic structure pronounced in mtDNA (overall F(ST) = 0.15) but moderate in microsatellites (F(ST) = 0.03). As predicted by its life history, philopatry, and limited capacity for dispersal, stone loach populations of Lake Constance show a clear pattern of isolation by distance. Geographic distances along the shores are the best explanation for the observed geographical distribution of genetic differentiation (r = 0.88), indicating that open water represents a barrier for the dispersal of the stone loach. The colonization of Lake Constance might have occurred initially at one location and then populations spread throughout the lake in a stepwise manner following the shoreline, and subsequently remained largely genetically isolated as suggested by the large observed differences among them.

  5. Umbilical cord blood and placental mercury, selenium and selenoprotein expression in relation to maternal fish consumption.

    PubMed

    Gilman, Christy L; Soon, Reni; Sauvage, Lynnae; Ralston, Nicholas V C; Berry, Marla J

    2015-04-01

    Seafood is an important source of nutrients for fetal neurodevelopment. Most individuals are exposed to the toxic element mercury through seafood. Due to the neurotoxic effects of mercury, United States government agencies recommend no more than 340g (12oz) per week of seafood consumption during pregnancy. However, recent studies have shown that selenium, also abundant in seafood, can have protective effects against mercury toxicity. In this study, we analyzed mercury and selenium levels and selenoprotein mRNA, protein, and activity in placenta of a cohort of women in Hawaii in relation to maternal seafood consumption assessed with dietary surveys. Fish consumption resulted in differences in mercury levels in placenta and cord blood. When taken as a group, those who consumed no fish exhibited the lowest mercury levels in placenta and cord blood. However, there were numerous individuals who either had higher mercury with no fish consumption or lower mercury with high fish consumption, indicating a lack of correlation. Placental expression of selenoprotein mRNAs, proteins and enzyme activity was not statistically different in any region among the different dietary groups. While the absence of seafood consumption correlates with lower average placental and cord blood mercury levels, no strong correlations were seen between seafood consumption or its absence and the levels of either selenoproteins or selenoenzyme activity.

  6. Umbilical cord blood and placental mercury, selenium and selenoprotein expression in relation to maternal fish consumption

    PubMed Central

    Gilman, Christy L.; Soon, Reni; Sauvage, Lynnae; Ralston, Nicholas V.C.; Berry, Marla J.

    2015-01-01

    Seafood is an important source of nutrients for fetal neurodevelopment. Most individuals are exposed to the toxic element mercury through seafood. Due to the neurotoxic effects of mercury, United States government agencies recommend no more than 340 g (12 oz) per week of seafood consumption during pregnancy. However, recent studies have shown that selenium, also abundant in seafood, can have protective effects against mercury toxicity. In this study, we analyzed mercury and selenium levels and selenoprotein mRNA, protein, and activity in placenta of a cohort of women in Hawaii in relation to maternal seafood consumption assessed with dietary surveys. Fish consumption resulted in differences in mercury levels in placenta and cord blood. When taken as a group, those who consumed no fish exhibited the lowest mercury levels in placenta and cord blood. However, there were numerous individuals who either had higher mercury with no fish consumption or lower mercury with high fish consumption, indicating a lack of correlation. Placental expression of selenoprotein mRNAs, proteins and enzyme activity was not statistically different in any region among the different dietary groups. While the absence of seafood consumption correlates with lower average placental and cord blood mercury levels, no strong correlations were seen between seafood consumption or its absence and the levels of either selenoproteins or selenoenzyme activity. PMID:25744505

  7. Selenium: Mercury Molar Ratios in Freshwater Fish in the Columbia River Basin: Potential Applications for Specific Fish Consumption Advisories.

    PubMed

    Cusack, Leanne K; Eagles-Smith, Collin; Harding, Anna K; Kile, Molly; Stone, Dave

    2016-12-08

    Fish provide a valuable source of beneficial nutrients and are an excellent source of low fat protein. However, fish are also the primary source of methylmercury exposure in humans. Selenium often co-occurs with mercury and there is some evidence that selenium can protect against mercury toxicity yet States issue fish consumption advisories based solely on the risks that methylmercury pose to human health. Recently, it has been suggested the selenium: mercury molar ratio be considered in risk management. In order for agencies to utilize the ratio to set consumption guidelines, it is important to evaluate the variability in selenium and mercury in different fish species. We examined 10 different freshwater fish species found within the Columbia River Basin in order to determine the inter- and intra-specific variability in the selenium: mercury molar ratios and the selenium health benefit values. We found significant variation in selenium: mercury molar ratios. The mean molar ratios for each species were all above 1:1, ranging from 3.42:1 in Walleye to 27.2:1 in Chinook salmon. There was a positive correlation between both mercury and selenium with length for each fish species apart from yellow perch and rainbow trout. All species had health benefit values greater than 2. We observed considerable variability in selenium: mercury molar ratios within fish species collected in the Columbia River Basin. Although incorporating selenium: mercury molar ratios into fish consumption holds the potential for refining advisories and assessing the risk of methylmercury exposure, the current understanding of how these ratios apply is insufficient, and further understanding of drivers of variability in the ratios is needed.

  8. Occurrence of the Great Lake's most recent invader, Hemimysis anomala, in the diet of fishes in southeastern Lake Ontario

    USGS Publications Warehouse

    Lantry, B.F.; Walsh, M.G.; Johnson, J.H.; McKenna, J.E.

    2010-01-01

    The Ponto-Caspian mysid, Hemimysis anomala, was first observed in southeastern Lake Ontario in May 2006. During July and August 2007, gill nets were fished in 6 to 8 m of water at two locations of known Hemimysis colonization in southeastern Lake Ontario to determine if fish that consume macroinvertebrates were beginning to include this new invasive mysid in their diets. Of nine fish species captured in August, September, and October 2007, three species had consumed Hemimysis: alewife (Alosa pseudoharengus), rock bass (Ambloplites rupestris), and yellow perch (Perca flavescens); and six species had not: round goby Apollonia melanostoma, smallmouth bass Micropterus dolomieu, spottail shiner Notropis hudsonius, gizzard shad Dorosoma cepedianum, white perch Morone americana and log perch Percina caprodes. Diets of alewives from all samples were composed predominantly of Hemimysis (69.6% -100% frequency of occurrence, 46.0%–74.5% dry weight diet composition). Two of 6 rock bass stomachs sampled in August contained ≥ 98.9% Hemimysis (10 and 40 individuals each) and one of 61 yellow perch stomachs sampled in September contained 10.0% Hemimysis (6 individuals) and 90.0% fish. While Hemimysis were observed only sparsely in the diet of most nearshore fish, their predominance in alewife diets and their omnivorous feeding behavior indicated that they have the potential to alter energy flow in Great Lakes' foodwebs.

  9. Thiamine and thiaminase status in forage fish of salmonines from Lake Michigan

    USGS Publications Warehouse

    Tillitt, D.E.; Zajicek, J.L.; Brown, S.B.; Brown, L.R.; Fitzsimons, J.D.; Honeyfield, D.C.; Holey, M.E.; Wright, G.M.

    2005-01-01

    Dietary sources of thiamine (vitamin B1) and thiamine-degrading enzymes (thiaminases) are thought to be primary factors in the development of thiamine deficiency among Great Lakes salmonines. We surveyed major forage fish species in Lake Michigan for their content of thiamine, thiamine vitamers, and thiaminase activity. Concentrations of total thiamine were similar (P ≤ 0.05) among most forage fishes (alewife Alosa pseudoharengus, bloater Coregonus hoyi, spottail shiner Notropis hudsonius, deepwater sculpin Myoxocephalus thompsonii, yellow perch Perca flavescens, ninespine stickleback Pungitius pungitius, and round goby Neogobius melanostomus) and slightly lower in rainbow smelt Osmerus mordax. Concentrations of total thiamine were all above the dietary requirements of coldwater fishes, suggesting the thiamine content of forage fish is not the critical factor in the development of thiamine deficiency in Lake Michigan salmonines. Thiamine pyrophosphate was the predominant form of thiamine in most species of forage fish, followed by free thiamine and thiamine monophosphate. Total thiamine was slightly greater in summer collections of alewife and rainbow smelt than in spring and fall collections, but the same was not true for bloater. Thiaminase activity varied among species and was greatest in gizzard shad Dorosoma cepedianum, spottail shiner, alewife, and rainbow smelt. Thiaminase activity in alewife varied among collection locations, season (greatest in spring), and size of the fish. Size and condition factors were positively correlated with both total thiamine and thiaminase activity in alewife. Thus, thiamine and thiaminase activity in forage fishes collected in Lake Michigan varied among species, seasons, year caught, and size (or condition). Therefore, multiple factors must be considered in the development of predictive models for the onset of thiamine deficiency in Great Lakes salmonines. Most importantly, thiaminase activity was great in alewives and

  10. Tracking Metal Pollution in Lake Chapala: Concentrations in Water, Sediments, and Fish.

    PubMed

    Torres, Zaria; Mora, Miguel A; Taylor, Robert J; Alvarez-Bernal, Dioselina

    2016-09-01

    We measured concentrations of selected metals (Al, Ba, Cu, Mn, Hg, Sr, V, and Zn) in water, sediments, and fish from Lake Chapala and a reference site to evaluate potential negative effects on wildlife, particularly fish-eating birds. Fish metal concentrations ranged from 0.05 µg/g wet weight (ww) for Al and Cu to 64.70 µg/g ww for Sr. There was a positive and significant correlation between fish length and metals particularly for Ba, Cu, Mn, and Zn in Lake Chapala (p < 0.05). However, there were no significant correlations between metal concentrations and δ(15)N values in fish indicating no biomagnification through the food web. Overall, metal concentrations in water, sediments, and fish were similar to and in some cases below those reported for Lake Chapala over the last 20 years. Also, metal concentrations were below those that could be of concern for negative effects on fish and wildlife of Lake Chapala.

  11. Seasonal fluctuations of DDTs and PCBs in zooplankton and fish of Lake Maggiore (Northern Italy).

    PubMed

    Bettinetti, Roberta; Quadroni, Silvia; Manca, Marina; Piscia, Roberta; Volta, Pietro; Guzzella, Licia; Roscioli, Claudio; Galassi, Silvana

    2012-07-01

    Concentrations of DDTs and PCBs were determined in the zooplankton and in three different fish species (shad, whitefish and roach) collected seasonally during 2009 and 2010 in three sites in Lake Maggiore, a south-alpine lake that has been contaminated by DDT since 1996. As previously observed in 2008, even during 2009 DDTs concentrations were higher in zooplankton than in fish, probably due to the very unstable situation of the lake still influenced by local inputs. The situation changed in 2010, when all DDT compounds increased in fish to levels much higher than those measured in zooplankton. Biomagnification was statistically demonstrated for pp'DDE in all the three fish species, indicating a probable signal of recovery of the lake. Although with respect to total PCBs we observed that the contamination levels varied across time periods and across fish species, biomagnification was evident from zooplankton to fish both in 2009 and in 2010. As concern individual PCBs, biomagnification from zooplankton to all three fish species was significant for PCB 153 and PCB 138.

  12. Mercury levels in herring gulls and fish: 42 years of spatio-temporal trends in the Great Lakes.

    PubMed

    Blukacz-Richards, E Agnes; Visha, Ariola; Graham, Matthew L; McGoldrick, Daryl L; de Solla, Shane R; Moore, David J; Arhonditsis, George B

    2017-04-01

    Total mercury levels in aquatic birds and fish communities have been monitored across the Canadian Great Lakes by Environment and Climate Change Canada (ECCC) for the past 42 years (1974-2015). These data (22 sites) were used to examine spatio-temporal variability of mercury levels in herring gull (Larus argentatus) eggs, lake trout (Salvelinus namaycush), walleye (Sander vitreus), and rainbow smelt (Osmerus mordax). Trends were quantified with dynamic linear models, which provided time-variant rates of change of mercury concentrations. Lipid content (in both fish and eggs) and length in fish were used as covariates in all models. For the first three decades, mercury levels in gull eggs and fish declined at all stations. In the 2000s, trends for herring gull eggs reversed at two sites in Lake Erie and two sites in Lake Ontario. Similar trend reversals in the 2000s were observed for lake trout in Lake Superior and at a single station in Lake Ontario. Mercury levels in lake trout continued to slowly decline at all of the remaining stations, except for Lake Huron, where the levels remained stable. A post-hoc Bayesian regression analysis suggests strong trophic interactions between herring gulls and rainbow smelt in Lake Superior and Lake Ontario, but also pinpoints the likelihood of a trophic decoupling in Lake Huron and Lake Erie. Continued monitoring of mercury levels in herring gulls and fish is required to consolidate these trophic shifts and further evaluate their broader implications.

  13. Lake eutrophication and brownification downgrade availability and transfer of essential fatty acids for human consumption.

    PubMed

    Taipale, S J; Vuorio, K; Strandberg, U; Kahilainen, K K; Järvinen, M; Hiltunen, M; Peltomaa, E; Kankaala, P

    2016-11-01

    Fish are an important source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for birds, mammals and humans. In aquatic food webs, these highly unsaturated fatty acids (HUFA) are essential for many physiological processes and mainly synthetized by distinct phytoplankton taxa. Consumers at different trophic levels obtain essential fatty acids from their diet because they cannot produce these sufficiently de novo. Here, we evaluated how the increase in phosphorus concentration (eutrophication) or terrestrial organic matter inputs (brownification) change EPA and DHA content in the phytoplankton. Then, we evaluated whether these changes can be seen in the EPA and DHA content of piscivorous European perch (Perca fluviatilis), which is a widely distributed species and commonly consumed by humans. Data from 713 lakes showed statistically significant differences in the abundance of EPA- and DHA-synthesizing phytoplankton as well as in the concentrations and content of these essential fatty acids among oligo-mesotrophic, eutrophic and dystrophic lakes. The EPA and DHA content of phytoplankton biomass (mgHUFAg(-1)) was significantly lower in the eutrophic lakes than in the oligo-mesotrophic or dystrophic lakes. We found a strong significant correlation between the DHA content in the muscle of piscivorous perch and phytoplankton DHA content (r=0.85) as well with the contribution of DHA-synthesizing phytoplankton taxa (r=0.83). Among all DHA-synthesizing phytoplankton this correlation was the strongest with the dinoflagellates (r=0.74) and chrysophytes (r=0.70). Accordingly, the EPA+DHA content of perch muscle decreased with increasing total phosphorus (r(2)=0.80) and dissolved organic carbon concentration (r(2)=0.83) in the lakes. Our results suggest that although eutrophication generally increase biomass production across different trophic levels, the high proportion of low-quality primary producers reduce EPA and DHA content in the food web up to predatory fish

  14. Association between Maternal Fish Consumption and Gestational Weight Gain: Influence of Molecular Genetic Predisposition to Obesity

    PubMed Central

    Larsen, Sofus C.; Ängquist, Lars; Laurin, Charles; Morgen, Camilla S.; Jakobsen, Marianne U.; Paternoster, Lavinia; Smith, George Davey; Olsen, Sjurdur F.; Sørensen, Thorkild I. A.; Nohr, Ellen A.

    2016-01-01

    Background Studies suggest that fish consumption can restrict weight gain. However, little is known about how fish consumption affects gestational weight gain (GWG), and whether this relationship depends on genetic makeup. Objective To examine the association between fish consumption and GWG, and whether this relationship is dependent on molecular genetic predisposition to obesity. Design A nested case-cohort study based on the Danish National Birth Cohort (DNBC) sampling the most obese women (n = 990) and a random sample of the remaining participants (n = 1,128). Replication of statistically significant findings was attempted in the Avon Longitudinal Study of Parents and Children (ALSPAC) (n = 4,841). We included 32 body mass index (BMI) associated single nucleotide polymorphisms (SNPs) and 5 SNPs found associated with GWG. BMI associated SNPs were combined in a genetic risk score (GRS). Associations between consumption of fish, GRS or individual variants and GWG were analysed, and interactions between fish and the GRS or individual variants were examined. Results In the DNBC, each portion/week (150 g) of fatty fish was associated with a higher GWG of 0.58 kg (95% CI: 0.16, 0.99, P<0.01). For total fish and lean fish, similar patterns were observed, but these associations were not statistically significant. We found no association between GRS and GWG, and no interactions between GRS and dietary fish on GWG. However, we found an interaction between the PPARG Pro12Ala variant and dietary fish. Each additional Pro12Ala G-allele was associated with a GWG of -0.83 kg (95% CI: -1.29, -0.37, P<0.01) per portion/week of dietary fish, with the same pattern for both lean and fatty fish. In ALSPAC, we were unable to replicate these findings. Conclusion We found no consistent evidence of association between fish consumption and GWG, and our results indicate that the association between dietary fish and GWG has little or no dependency on GRS or individual SNPs. PMID:26930408

  15. Changes in Meat/Poultry/Fish Consumption in Australia: From 1995 to 2011–2012

    PubMed Central

    Sui, Zhixian; Raubenheimer, David; Cunningham, Judy; Rangan, Anna

    2016-01-01

    The purpose of the study was to examine temporal changes in meat/poultry/fish consumption patterns between 1995 and 2011–2012 in the Australian population. Meat/poultry/fish consumption from all food sources, including recipes, was analysed by gender, age group, and socio-economic status using 24-h recall data from the 1995 National Nutrition Survey (n = 13,858) and the 2011–2012 National Nutrition and Physical Activity Survey (n = 12,153). The overall proportion of people consuming meat/poultry/fish remained stable (91.7% versus 91.3%, p = 0.55), but a shift in the type of meat consumed was observed. Red meat, including beef and lamb, was consumed by fewer people over the time period (from 56% to 49%), whereas poultry consumption increased (from 29% to 38%). Amounts of all meat/poultry/fish consumed were reportedly higher in 2011–2012 compared with 1995. This resulted in similar (red meat, and processed meat) or slightly higher (poultry, and fish) per-capita intakes in 2011–2012. The magnitude of change of consumption varied between children and adults, and by gender. Monitoring trends in consumption is particularly relevant to policy makers, researchers and other health professionals for the formulation of dietary recommendations and estimation of potential health outcomes. PMID:27886131

  16. Changes in Meat/Poultry/Fish Consumption in Australia: From 1995 to 2011-2012.

    PubMed

    Sui, Zhixian; Raubenheimer, David; Cunningham, Judy; Rangan, Anna

    2016-11-24

    The purpose of the study was to examine temporal changes in meat/poultry/fish consumption patterns between 1995 and 2011-2012 in the Australian population. Meat/poultry/fish consumption from all food sources, including recipes, was analysed by gender, age group, and socio-economic status using 24-h recall data from the 1995 National Nutrition Survey (n = 13,858) and the 2011-2012 National Nutrition and Physical Activity Survey (n = 12,153). The overall proportion of people consuming meat/poultry/fish remained stable (91.7% versus 91.3%, p = 0.55), but a shift in the type of meat consumed was observed. Red meat, including beef and lamb, was consumed by fewer people over the time period (from 56% to 49%), whereas poultry consumption increased (from 29% to 38%). Amounts of all meat/poultry/fish consumed were reportedly higher in 2011-2012 compared with 1995. This resulted in similar (red meat, and processed meat) or slightly higher (poultry, and fish) per-capita intakes in 2011-2012. The magnitude of change of consumption varied between children and adults, and by gender. Monitoring trends in consumption is particularly relevant to policy makers, researchers and other health professionals for the formulation of dietary recommendations and estimation of potential health outcomes.

  17. Monophyletic origin of Lake Victoria cichlid fishes suggested by mitochondrial DNA sequences.

    PubMed

    Meyer, A; Kocher, T D; Basasibwaki, P; Wilson, A C

    1990-10-11

    Lake Victoria, together with its satellite lakes, harbours roughly 200 endemic forms of cichlid fishes that are classified as 'haplochromines' and yet the lake system is less than a million years old. This 'flock' has attracted attention because of the possibility that it evolved within the lake from one ancestral species and that biologists are thus presented with a case of explosive evolution. Within the past decade, however, morphology has increasingly emphasized the view that the flock may be polyphyletic. We sequenced up to 803 base pairs of mitochondrial DNA from 14 representative Victorian species and 23 additional African species. The flock seems to be monophyletic, and is more akin to that from Lake Malawi than to species from Lake Tanganyika; in addition, it contains less genetic variation than does the human species, and there is virtually no sharing of mitochondrial DNA types among species. These results confirm that the founding event was recent.

  18. The Adaptive Radiation of Cichlid Fish in Lake Tanganyika: A Morphological Perspective

    PubMed Central

    Takahashi, Tetsumi; Koblmüller, Stephan

    2011-01-01

    Lake Tanganyika is the oldest of the Great Ancient Lakes in the East Africa. This lake harbours about 250 species of cichlid fish, which are highly diverse in terms of morphology, behaviour, and ecology. Lake Tanganyika's cichlid diversity has evolved through explosive speciation and is treated as a textbook example of adaptive radiation, the rapid differentiation of a single ancestor into an array of species that differ in traits used to exploit their environments and resources. To elucidate the processes and mechanisms underlying the rapid speciation and adaptive radiation of Lake Tanganyika's cichlid species assemblage it is important to integrate evidence from several lines of research. Great efforts have been, are, and certainly will be taken to solve the mystery of how so many cichlid species evolved in so little time. In the present review, we summarize morphological studies that relate to the adaptive radiation of Lake Tanganyika's cichlids and highlight their importance for understanding the process of adaptive radiation. PMID:21716857

  19. Expansion of Dreissena into offshore waters of Lake Michigan and potential impacts on fish populations

    USGS Publications Warehouse

    Bunnell, D.B.; Madenjian, C.P.; Holuszko, J.D.; Adams, J.V.; French, J. R. P.

    2009-01-01

    Lake Michigan was invaded by zebra mussels (Dreissena polymorpha) in the late 1980s and then followed by quagga mussels (D. bugensis) around 1997. Through 2000, both species (herein Dreissena) were largely restricted to depths less than 50??m. Herein, we provide results of an annual lake-wide bottom trawl survey in Lake Michigan that reveal the relative biomass and depth distribution of Dreissena between 1999 and 2007 (although biomass estimates from a bottom trawl are biased low). Lake-wide mean biomass density (g/m2) and mean depth of collection revealed no trend between 1999 and 2003 (mean = 0.7??g/m2 and 37??m, respectively). Between 2004 and 2007, however, mean lake-wide biomass density increased from 0.8??g/m2 to 7.0??g/m2, because of increased density at depths between 30 and 110??m, and mean depth of collection increased from 42 to 77??m. This pattern was confirmed by a generalized additive model. Coincident with the Dreissena expansion that occurred beginning in 2004, fish biomass density (generally planktivores) declined 71% between 2003 and 2007. Current understanding of fish population dynamics, however, indicates that Dreissena expansion is not the primary explanation for the decline of fish, and we provide a species-specific account for more likely underlying factors. Nonetheless, future sampling and research may reveal a better understanding of the potential negative interactions between Dreissena and fish in Lake Michigan and elsewhere.

  20. Sustainability of the Lake Superior fish community: Interactions in a food web context

    USGS Publications Warehouse

    Kitchell, James F.; Cox, Sean P.; Harvey, Chris J.; Johnson, Timothy B.; Mason, Doran M.; Schoen, Kurt K.; Aydin, Kerim; Bronte, Charles; Ebener, Mark; Hansen, Michael; Hoff, Michael; Schram, Steve; Schreiner, Don; Walters, Carl J.

    2000-01-01

    The restoration and rehabilitation of the native fish communities is a long-term goal for the Laurentian Great Lakes. In Lake Superior, the ongoing restoration of the native lake trout populations is now regarded as one of the major success stories in fisheries management. However, populations of the deepwater morphotype (siscowet lake trout) have increased much more substantially than those of the nearshore morphotype (lean lake trout), and the ecosystem now contains an assemblage of exotic species such as sea lamprey, rainbow smelt, and Pacific salmon (chinook, coho, and steelhead). Those species play an important role in defining the constraints and opportunities for ecosystem management. We combined an equilibrium mass balance model (Ecopath) with a dynamic food web model (Ecosim) to evaluate the ecological consequences of future alternative management strategies and the interaction of two different sets of life history characteristics for fishes at the top of the food web. Relatively rapid turnover rates occur among the exotic forage fish, rainbow smelt, and its primary predators, exotic Pacific salmonids. Slower turnover rates occur among the native lake trout and burbot and their primary prey—lake herring, smelt, deepwater cisco, and sculpins. The abundance of forage fish is a key constraint for all salmonids in Lake Superior. Smelt and Mysis play a prominent role in sustaining the current trophic structure. Competition between the native lake trout and the exotic salmonids is asymmetric. Reductions in the salmon population yield only a modest benefit for the stocks of lake trout, whereas increased fishing of lake trout produces substantial potential increases in the yields of Pacific salmon to recreational fisheries. The deepwater or siscowet morphotype of lake trout has become very abundant. Although it plays a major role in the structure of the food web it offers little potential for the restoration of a valuable commercial or recreational fishery

  1. Trends of brominated diphenyl ethers in fresh and archived Great Lakes fish (1979-2005)

    USGS Publications Warehouse

    Batterman, Stuart; Chernyak, Sergei; Gwynn, Erica; Cantonwine, David; Jia, Chunrong; Begnoche, Linda J.; Hickey, James P.

    2007-01-01

    While few environmental measurements of brominated diphenyl ethers (BDEs) were completed prior to the mid-1990s, analysis of appropriately archived samples might enable the determination of contaminant trends back to the introduction of these chemicals. In this paper, we first investigate the stability of BDEs in archived frozen and extracted fish samples, and then characterize trends of these chemicals in rainbow smelt (Osmerus mordax) and lake trout (Salvelinus namaycush) in each of the Great Lakes between 1979 and 2005. We focus on the four most common congeners (BDE-47, 100, 99 and 153) and use a change-point analysis to detect shifts in trends. Analyses of archived fish samples yielded precise BDE concentration measurements with only small losses (0.8% per year in frozen fish tissues, 2.2% per year in refrigerated extracts). Trends in fish from all Great Lakes showed large increases in BDE concentrations that started in the early to mid-1980s with fairly consistent doubling times (generally 2–4 years except in Lake Erie smelt where levels increased very slowly), though concentrations and trends show differences by congener, fish species and lake. The most recent data show that accumulation rates are slowing, and concentrations of penta- and hexa-congeners in trout from Lakes Ontario and Michigan and smelt from Lake Ontario started to decrease in the mid-1990s. Trends in smelt and trout are evolving somewhat differently, and trout concentrations in the five lakes are now ranked as Michigan > Superior = Ontario > Huron = Erie, and smelt concentrations as Michigan > Ontario > Huron > Superior > Erie. The analysis of properly archived samples permits the reconstruction of historical trends, congener distributions, biomagnification and other information that can aid the understanding and management of these contaminants.

  2. The offshore fish community in southern Lake Ontario, 1972-1998

    USGS Publications Warehouse

    Owens, Randall W.; O'Gorman, Robert; Eckert, Thomas H.; Lantry, Brian F.; Munawar, M.

    2003-01-01

    The authors document the status of Lake Ontario's open-water fish community in 1972, near the beginning of an era of massive fish stocking and when phosphorus levels in the lake from anthropogenic inputs, were near their peak. They then describe changes that occurred in the fish community in 1978-98. This was a period when large numbers of young salmonid piscivores were released annually, sea lamprey control continued to improve, and phosphorus levels were declining due to successful nutrient abatement programs. Coincident with the above, the lower food web was changed by the addition of new exotic invertebrates, the zooplankter Bythotrephes cederstroemi and particularly the zebra mussel, Dreissena polymorpha, and quagga mussel, D. bugensis. The picture of the fish community structure is drawn from records of catches in bottom trawls and gill nets during surveys of southern Lake Ontario conducted the the U.S. Geological Survey (USGS) and the New York Department of Environmental Conservation (NYDEC), from records of fish stocked in Lake Ontario by the NYDEC, and from a creel census of boat anglers returning to southern Lake Ontario ports conducted by the NYDEC.

  3. Characterization factors for water consumption and greenhouse gas emissions based on freshwater fish species extinction.

    PubMed

    Hanafiah, Marlia M; Xenopoulos, Marguerite A; Pfister, Stephan; Leuven, Rob S E W; Huijbregts, Mark A J

    2011-06-15

    Human-induced changes in water consumption and global warming are likely to reduce the species richness of freshwater ecosystems. So far, these impacts have not been addressed in the context of life cycle assessment (LCA). Here, we derived characterization factors for water consumption and global warming based on freshwater fish species loss. Calculation of characterization factors for potential freshwater fish losses from water consumption were estimated using a generic species-river discharge curve for 214 global river basins. We also derived characterization factors for potential freshwater fish species losses per unit of greenhouse gas emission. Based on five global climate scenarios, characterization factors for 63 greenhouse gas emissions were calculated. Depending on the river considered, characterization factors for water consumption can differ up to 3 orders of magnitude. Characterization factors for greenhouse gas emissions can vary up to 5 orders of magnitude, depending on the atmospheric residence time and radiative forcing efficiency of greenhouse gas emissions. An emission of 1 ton of CO₂ is expected to cause the same impact on potential fish species disappearance as the water consumption of 10-1000 m³, depending on the river basin considered. Our results make it possible to compare the impact of water consumption with greenhouse gas emissions.

  4. Selective transfer of polyunsaturated fatty acids from phytoplankton to planktivorous fish in large boreal lakes.

    PubMed

    Strandberg, Ursula; Hiltunen, Minna; Jelkänen, Elli; Taipale, Sami J; Kainz, Martin J; Brett, Michael T; Kankaala, Paula

    2015-12-01

    Lake size influences various hydrological parameters, such as water retention time, circulation patterns and thermal stratification that can consequently affect the plankton community composition, benthic-pelagic coupling and the function of aquatic food webs. Although the socio-economical (particularly commercial fisheries) and ecological importance of large lakes has been widely acknowledged, little is known about the availability and trophic transfer of polyunsaturated fatty (PUFA) in large lakes. The objective of this study was to investigate trophic trajectories of PUFA in the pelagic food web (seston, zooplankton, and planktivorous fish) of six large boreal lakes in the Finnish Lake District. Docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and α-linolenic acid (ALA) were the most abundant PUFA in pelagic organisms, particularly in the zooplanktivorous fish. Our results show that PUFA from the n-3 family (PUFAn-3), often associated with marine food webs, are also abundant in large lakes. The proportion of DHA increased from ~4±3% in seston to ~32±6% in vendace (Coregonus albula) and smelt (Osmerus eperlanus), whereas ALA showed the opposite trophic transfer pattern with the highest values observed in seston (~11±2%) and the lowest in the opossum shrimp (Mysis relicta) and fish (~2±1%). The dominance of diatoms and cryptophytes at the base of the food web in the study lakes accounted for the high amount of PUFAn-3 in the planktonic consumers. Furthermore, the abundance of copepods in the large lakes explains the effective transfer of DHA to planktivorous fish. The plankton community composition in these lakes supports a fishery resource (vendace) that is very high nutritional quality (in terms of EPA and DHA contents) to humans.

  5. Native Salamanders and Introduced Fish: Changing the Nature of Mountain Lakes and Ponds

    USGS Publications Warehouse

    Larson, Gary L.; Hoffman, Robert L.

    2003-01-01

    During the last century, many fishless mountain lakes and ponds in the Pacific Northwest were stocked with non-native fish, such as brook trout, for recreational purposes. These introduced fish replaced long-toed and northwestern salamander larvae as the top aquatic vertebrate predator by preying on salamander larvae. This predatory interaction has been shown to reduce the abundances of larval salamander populations. We conducted studies in two national parks to assess the abundances of salamander larvae in lakes with and without introduced fish. These studies suggest that the two salamander species were affected quite differently by the presence of introduced fish because of different life-history traits and different distributions of salamanders and fish within each park.

  6. Fish consumption and contaminant exposure among Montreal-area sportfishers: Pilot study

    SciTech Connect

    Kosatsky, T. |; Przybysz, R.; Shatenstein, B.; Weber, J.P.; Armstrong, B.

    1999-02-01

    A 1995 pilot study assessed sport fish consumption and contaminant exposure among Montreal-area residents fishing the frozen St. Lawrence river. Interviews conducted among 223 ice fishers met on-site were used to create an index of estimated exposure to fish-borne contaminants. A second-stage assessment of sport fish consumption and tissue contaminant burdens included 25 interviewees at the highest level of estimated contaminant exposure and 15 low-exposure fishers. High-level fisher-consumers reported eating 0.92 {+-} 0.99 sport fish meals/week during the previous 3 weeks compared to 0.38 {+-} 0.21 for the low-level group. Based on the product of consumption frequency times mass of sport fish meals consumed, high-level consumers ate a mean of 18.3 kg of sport fish annually versus 3.3 kg for the low-level consumers. Tissue contaminant assessments showed significant groupwise differences: 0--1 cm hair mercury, lipid-adjusted plasma PCB congeners, and lipid-adjusted plasma DDE. No participant had a hair mercury or plasma DDE concentration above Health Canada recommendations but 2/25 high-level participants had plasma Aroclor 1260 concentrations above recommended limits.

  7. Historical changes in the major fish resources of the Great Lakes

    USGS Publications Warehouse

    Hartman, Wilbur L.; Evans, Marlene S.

    1988-01-01

    My purpose here is to review historic changes in the major fish resources of the five Great Lakes, and to identify the cause or causes for those changes. In some instances it will be clear that intensive fishing was the primary cause of change; in other instances it will be nearly as clear that predation by the sea lamprey played a significant if not dominant role in change; and in still others it will be clear (or at least circumstantial) that exotic species other than the sea lamprey have been implicated. The exotics that have invaded or been accidentally or purposefully released into the Great Lakes system have not only adversely affected indigenous fishes, but some have developed into new and valuable resources. However, when it comes to degradation of water quality and of critical habitat, the linkages to changes in fish populations are neither clear-cut nor quantifiable — their impacts were generally far more subtle and difficult to detect, but not necessarily of less importance. Inasmuch as a comprehensive review of all changes in fishery resources, water quality, and habitat conditions in the Great Lakes would be encyclopedic, I confine discussion here to prime examples related to the most historically important fish resources. One of the values of the approach used in this manuscript is the collation in a single-source document of the conclusions reached by many scientists on reasons for changes in the fish resources across the Great Lakes basin.

  8. Water quality and fish dynamics in forested wetlands associated with an oxbow lake

    USGS Publications Warehouse

    Andrews, Caroline S.; Miranda, Leandro E.; Kroger, Robert

    2015-01-01

    Forested wetlands represent some of the most distinct environments in the Lower Mississippi Alluvial Valley. Depending on season, water in forested wetlands can be warm, stagnant, and oxygen-depleted, yet may support high fish diversity. Fish assemblages in forested wetlands are not well studied because of difficulties in sampling heavily structured environments. During the April–July period, we surveyed and compared the water quality and assemblages of small fish in a margin wetland (forested fringe along a lake shore), contiguous wetland (forested wetland adjacent to a lake), and the open water of an oxbow lake. Dissolved-oxygen levels measured hourly 0.5 m below the surface were higher in the open water than in either of the forested wetlands. Despite reduced water quality, fish-species richness and catch rates estimated with light traps were greater in the forested wetlands than in the open water. The forested wetlands supported large numbers of fish and unique fish assemblages that included some rare species, likely because of their structural complexity. Programs developed to refine agricultural practices, preserve riparian zones, and restore lakes should include guidance to protect and reestablish forested wetlands.

  9. Temporal trends of polychlorinated biphenyls and organochlorine pesticides in Great Lakes fish, 1999-2009.

    PubMed

    Chang, Fengchih; Pagano, James J; Crimmins, Bernard S; Milligan, Michael S; Xia, Xiaoyan; Hopke, Philip K; Holsen, Thomas M

    2012-11-15

    Temporal trend analysis of the latest Great Lake Fish Monitoring and Surveillance Program (GLFMSP) data showed statistically significant decreases in persistent bioaccumulative and toxic (PBT) contaminant (polychlorinated biphenyls (PCBs), dichloro-diphenyl-trichlorethane and its metabolites (DDTs), dieldrin, cis-chlordane, oxychlordane, cis-nonachlor) concentrations in Lakes Huron, Ontario, and Michigan lake trout over the period of 1999 to 2009. In contrast, for most contaminants, no statistically significant concentration trends were found in top predator fish in Lakes Superior and Erie during the same period. For Lakes Huron, Ontario, and Michigan 5.0 ± 2.6% average annual concentration decreases were found for PCBs, DDTs, dieldrin, and other organochlorine pesticides (OCs) decreased at a faster rate, ranging from 10 ± 4.3% to 20 ± 7.1% per year. For these three lakes, with the exception of PCBs, these current decreases are greater than were shown by an earlier trend analysis that estimated an annual contaminant decrease of about 2-5% for the period of 1980 to 2003. For Lakes Superior and Erie, the finding of no statistically significant trend is in agreement with previously reported results for these lakes.

  10. Zooplankton Successions in Neighboring Lakes with Contrasting Impacts of Amphibian and Fish Predators

    NASA Astrophysics Data System (ADS)

    Schabetsberger, Robert; Grill, Susanne; Hauser, Gabriele; Wukits, Petra

    2006-06-01

    Two pairs of neighboring subalpine lakes located in the Northern Calcareous Alps of Austria were investigated. Each pair comprised a deeper lake containing European minnows (Phoxinus phoxinus ), and a corresponding shallower lake harboring Alpine newts (Triturus alpestris ) as top predators. Plankton successions within fish and amphibian lakes differed markedly from each other. Throughout the year rotifers numerically dominated within the minnow lakes, while pigmented copepods (Genera Heterocope, Acanthodiaptomus , Arctodiaptomus , Mixodiaptomus ) and Daphnia were prominent in the amphibian lakes, at least early during the ice-free period. We argue that size-selective predation by minnows was the ultimate reason for this predominance of smaller zooplankton. While one of the minnow lakes was characterized by a succession of spatially and temporally segregated rotifer species, the other minnow lake permitted the development of populations of small-sized Bosmina and Ceriodaphnia during summer, probably due to the existence of a strong oxycline allowing zooplankton crustaceans to avoid predation from shore-based shoals of minnows. Once trout were introduced into this lake, minnows were visibly reduced in abundance. Bosmina and Ceriodaphnia disappeared and Daphnia together with a predacious copepod (Heterocope ) emerged either from egg banks or arrived from nearby source populations. We argue that the crustacean communities within the fishless lakes were adapted to the comparatively weak predation rates of Alpine newts.

  11. Meat and fish consumption and cancer in Canada.

    PubMed

    Hu, Jinfu; La Vecchia, Carlo; DesMeules, Marie; Negri, Eva; Mery, Les

    2008-01-01

    In this study, we examined the association between meat and fish intake and the risk of various cancers. Mailed questionnaires were completed by 19,732 incident, histologically confirmed cases of cancer of the stomach, colon, rectum, pancreas, lung, breast, ovary, prostate, testis, kidney, bladder, brain, non-Hodgkin's lymphomas (NHL), and leukemia and 5,039 population controls between 1994 and 1997 in 8 Canadian provinces. Measurement included information on socioeconomic status, lifestyle habits, and diet. A 69-item food frequency questionnaire provided data on eating habits 2 yr before data collection. Odds ratios and 95% confidence intervals were derived through unconditional logistic regression. Total meat and processed meat were directly related to the risk of stomach, colon, rectum, pancreas, lung, breast (mainly postmenopausal), prostate, testis, kidney, bladder, and leukemia. Red meat was significantly associated with colon, lung (mainly in men), and bladder cancer. No relation was observed for cancer of the ovary, brain, and NHL. No consistent excess risk emerged for fish and poultry, which were inversely related to the risk of a number of cancer sites. These findings add further evidence that meat, specifically red and processed meat, plays an unfavorable role in the risk of several cancers. Fish and poultry appear to be favorable diet indicators.

  12. Women's independent access to productive resources: fish ponds in the Oxbow Lakes Project, Bangladesh.

    PubMed

    Nathan, D; Apu, N A

    1998-01-01

    This article analyzes the experiences of women in acquiring user rights to fish ponds on government owned lands in the Oxbow Lakes Project in Bangladesh. The analysis describes the significance, functioning, and problems of women in fish farming. The field reports were based on the authors' involvement in implementation of the extension of fishing rights to women during 6 weeks/year over 4 years. Analysis was based on observations and discussions during project implementation and on a survey conducted in March 1997. The project involved land reforms that transferred rights to a group of poor people. Most of the lakes had been overfished. The poor fishers were organized into Lake Fishing Teams (LFTs) with the right to culture and harvest fish in lakes that were under common property management. In late 1994, at least 50% of the women were included in the Fish Farming Groups (FFGs) to manage fish culture in ponds constructed in shallow areas of the lake shore. The proportion of women was increased to 75% in 1994-95 and favored women-headed households. By March 1997, there were 510 members of FFGs, of whom 84% were single, poor women. Women had low participation in fish sales and netting and guarding the harvest. Women in mixed gender groups complained that men dominated the key decision-making and financial areas. Production averaged 1500 kg/hectare in 1995-96. FFGs had higher expenses for feed and fertilizer than LFTs. This endeavor earned higher per capita income than poultry raising. All women groups performed better than mixed groups. These groups increased assertiveness and self-confidence.

  13. The effect of zebra mussel consumption on growth of freshwater drum in Lake Erie

    USGS Publications Warehouse

    French, John R. P.; Bur, Michael T.

    1996-01-01

    We examined food habits and scale annuli of freshwater drum (Aplodinotus grunniens) from western Lake Erie to determine whether increasing predation on zebra mussels (Dreissena polymorpha) had affected growth of freshwater drum. The volume of zebra mussels in drum guts was greater in older fish. Growth of age classes 3–4, which consumed few zebra mussels, was greater in the most productive year for zebra mussels, July 1990–August 1991, than in three prior years. The total lengths of 5-year-old drum changed little. The mean total length of 6-year-old females has declined since the zebra mussel invaded Lake Erie, even through mussels comprised more than two-thirds of gut samples in these fish. These studies suggest that zebra mussels may not benefit freshwater drum when serving as a staple in the diet. PDF

  14. Early detection of non-indigenous fishes in Lake Superior

    EPA Science Inventory

    Invasive species pose a serious threat to the ecological stability of the Great Lakes warranting continual monitoring for the arrival of new species. Three locations in Lake Superior were identified as “high risk” for new introductions: St. Louis River near Duluth, M...

  15. Early detection of invasive fishes in Lake Superior

    EPA Science Inventory

    Invasive species pose a serious threat to the Great Lakes warranting continual monitoring for the arrival of new species. Three locations in Lake Superior were identified as "high risk" for new introductions: St. Louis River near Duluth, MN, Upper St. Marys River near S...

  16. Temporal variation of blood and hair mercury levels in pregnancy in relation to fish consumption history in a population living along the St. Lawrence River.

    PubMed

    Morrissette, Joëlle; Takser, Larissa; St-Amour, Genevieve; Smargiassi, Audrey; Lafond, Julie; Mergler, Donna

    2004-07-01

    Fish consumption from the Great Lakes and the St. Lawrence River has been decreasing over the last years due to advisories and increased awareness of the presence of several contaminants. Methylmercury (MeHg), a well-established neurotoxicant even at low levels of exposure, bioaccumulates to differing degrees in various fish species and can have serious adverse effects on the development and functioning of the human central nervous system, especially during prenatal exposure. Most studies on MeHg exposure have focussed on high-level consumers from local fish sources, although mercury (Hg) is also present in fresh, frozen, and canned market fish. Moreover, little information exists on the temporal variation of blood and hair Hg in pregnant women, particularly in populations with low levels of Hg. The aim of the present study was to characterize the temporal variation of Hg during pregnancy and to investigate the relation between fish consumption from various sources prior to and during pregnancy and maternal cord blood and mother's hair Hg levels. We recruited 159 pregnant women from Southwest Quebec through two prenatal clinics of the Quebec Public Health System. All women completed two detailed questionnaires concerning their fish consumption (species and frequency) prior to and during pregnancy. The women also provided blood samples for all three trimesters of pregnancy and hair samples after delivery of up to 9 cm in length. Blood and hair Hg levels were analyzed by cold-vapor atomic-absorption and -fluorescence spectrometry methods, respectively. Results showed that maternal blood and hair Hg levels decreased significantly between the second and third trimesters of pregnancy. However, cord blood Hg was significantly higher than maternal blood at birth. Maternal hair was correlated with Hg blood concentration and was highly predictive of the organic fraction in cord blood. A strong dose relation was observed between the frequency of fish consumption before and

  17. Assemblage patterns of fish functional groups relative to habitat connectivity and conditions in floodplain lakes

    USGS Publications Warehouse

    Miyazono, S.; Aycock, J.N.; Miranda, L.E.; Tietjen, T.E.

    2010-01-01

    We evaluated the influences of habitat connectivity and local environmental factors on the distribution and abundance patterns of fish functional groups in 17 floodplain lakes in the Yazoo River Basin, USA. The results of univariate and multivariate analyses showed that species-environmental relationships varied with the functional groups. Species richness and assemblage structure of periodic strategists showed strong and positive correlations with habitat connectivity. Densities of most equilibrium and opportunistic strategists decreased with habitat connectivity. Densities of certain equilibrium and opportunistic strategists increased with turbidity. Forested wetlands around the lakes were positively related to the densities of periodic and equilibrium strategists. These results suggest that decreases in habitat connectivity, forested wetland buffers and water quality resulting from environmental manipulations may cause local extinction of certain fish taxa and accelerate the dominance of tolerant fishes in floodplain lakes. ?? 2010 John Wiley & Sons A/S.

  18. Seasonal bathymetric distributions of 16 fishes in Lake Superior, 1958-75

    USGS Publications Warehouse

    Selgeby, James H.; Hoff, Michael H.

    1996-01-01

    The bathymetric distributions of fishes in Lake Superior, which is one of the largest and deepest lakes in the world, has not been studied on a lakewide scale. Knowledge about the bathymetric distributions will aid in designing fish sampling programs, estimating absolute abundances, and modeling energy flow in the lake. Seasonal bathymetric distributions were determined , by 10-m depth intervals, for 16 fishes collected with bottom trawls and bottom-set gill nets within the upper 150 m of Lake Superior during 1958-75. In spring trawl catches, maximum abundance occurred at these depths: 15 m for round whitefish (Prosopium cylindraceum); 25m for longnose sucker (Catostomus catostomus); 35 m for lake whitefish (Coregonus clupeaformis) and rainbow smelt (Osmerus mordax); 45 m for lake trout (Salvelinus namaycush); 65 m for pygmy whitefish (Prospoium coulteri) and bloater (Coregonus hoyi); 75 m for trout- perch (Percopsis omiscomaycus); 105 m for shortjaw cisco (Coregonus zenithicus); and 115 m for ninespine stickleback (Pungitius pungitius), burbot (Lota lota), slimy sculpin (Cottus cogantus), spoonhead sculpin (Cottus ricei), and deepwater sculpin (Myoxcephalus thompsoni). Bathymetric distributions in spring gill nets were similar to those in trawls, except that depths of maximum abundances in gill nets were shallower than those in trawls for lake trout, rainbow smelt, longnose sucker, and burbot. Lake herring (Coregonus artedi) and kiyi (Coregonus kiyi) were rarely caught in trawls, and their maximum abundances in spring gill net collections were at depths of 25 and 145 m, respectively. In summer, pygmy whitefish, shortjaw cisco, lake herring, kiyi, longnose sucker, burbot, ninespine stickleback, trout-perch, slimy sculpin, and spponhead sculpin were at shallower depths than in spring, whereas rainbow smelt were found in deeper water; there was no change for other species. In fall, shortjaw cisco was at shallower depths than in summer, whereas the remaining species

  19. Perfluorinated Compounds in Fish from U.S. Urban Rivers and the Great Lakes

    EPA Science Inventory

    Perfluorinated compounds (PFCs) have recently received scientific and regulatory attention due to their broad environmental distribution, persistence, bioaccumulative potential, and toxicity. Some studies suggest that the consumption of fish from contaminated waters may be a maj...

  20. A risk-benefit analysis of French high fish consumption: a QALY approach.

    PubMed

    Guevel, Marie-Renée; Sirot, Véronique; Volatier, Jean-Luc; Leblanc, Jean-Charles

    2008-02-01

    The health risk and the nutritional benefit of a food are usually assessed separately. Toxicologists recommend limiting the consumption of certain fish because of methylmercury; while nutritionists recommend eating more oily fish because of omega 3. A common evaluation is imperative to provide coherent recommendations. In order to evaluate the risks along with the benefits related to fish consumption, a common metric based on the quality-adjusted life year (QALY) method has been used. The impact of a theoretical change from a medium n-3 PUFAs intake to a high intake is studied, in terms of the cardiovascular system (CHD mortality, stroke mortality and morbidity) and on fetal neuronal development (IQ loss or gain). This application can be considered as a sensitive analysis of the model used and looks at the impact of changing the dose-response relationships between cardiovascular diseases and n-3 PUFAs intakes. Results show that increasing fish consumption may have a beneficial impact on health. However, the confidence interval of the overall estimation has a negative lower bound, which means that this increase in fish consumption may have a negative impact due to MeHg contamination. Some limits of the QALY approach are identified. The first concerns determination of the dose-response relationships. The second concerns the economic origins of the approach and of individual preferences. Finally, since only one beneficial aspect and one risk element were studied, consideration should be given to how other beneficial and risk components may be integrated in the model.

  1. Hair mercury levels in relation to fish consumption in a community of the Moroccan Mediterranean coast.

    PubMed

    Elhamri, Hecham; Idrissi, Larbi; Coquery, Marina; Azemard, Sabine; El Abidi, Abdellah; Benlemlih, Mohamed; Saghi, Mohamed; Cubadda, Francesco

    2007-11-01

    Coastal populations with high seafood consumption in the Mediterranean have a significant exposure to dietary methylmercury, and areas where environmental mercury pollution is an issue due to industrial activities are of special concern. The study was undertaken with the aim of assessing methylmercury exposure through fish consumption in a community of north Morocco and characterizing the relevant health risk. Concentrations of total mercury were determined in human hair, a biomarker of methylmercury exposure, and in locally consumed fish by cold vapour atomic absorption spectrophotometry. Based on consumption frequencies reported by the 108 subjects included in the study the weekly intake of methylmercury was estimated and biomarker data were evaluated in relation to the estimated intake and the sociodemographic characteristics of the population. Multiple regression analysis was employed for the interpretation of hair mercury data in relation to fish consumption frequency, gender and the age of individuals. Mercury concentrations in hair ranged from 0.22 to 9.56 microg g(-1) (geometric mean = 1.79 microg g(-1)) and were closely related to fish intake. Fisherman and their families consumed fish three to five times per week and were the most exposed population subgroup. A high proportion of women of child-bearing age (50%) had relatively high levels of mercury in their hair (3.08-7.88 microg g(-1)).

  2. Fish Consumption Moderates Depressive Symptomatology in Elderly Men and Women from the IKARIA Study

    PubMed Central

    Chrysohoou, Christina; Tsitsinakis, George; Siassos, Gerassimos; Psaltopoulou, Theodora; Galiatsatos, Nikos; Metaxa, Vasiliki; Lazaros, George; Miliou, Antigoni; Giakoumi, Evaggelia; Mylonakis, Charalambos; Zaromytidou, Marina; Economou, Evaggelos; Triantafyllou, Georgia; Pitsavos, Christos; Stefanadis, Christodoulos

    2011-01-01

    Background. The aim was to examine the association of depressive symptoms with fish eating habits, in elderly individuals. Methods. From June to October of 2009, we studied 330 men and 343 women, aged 65 to 100 years, permanent inhabitants of Ikaria Island. Among several characteristics, depression was assessed with the Geriatric Depression scale (GDS range 0–15), while dietary habits through a valid semiquantitative food frequency questionnaire. Results. Women had significantly higher values of the GDS compared to men (4.8 ± 3.5 versus 3.3 ± 3.1, P = .001). Participants in the upper tertile of depression scale ate less frequent fish and consumed higher quantities of alcohol, compared to those in the lowest tertile (all P < .05). Regarding fish consumption, 50% of the individuals reported consuming 1-2 times weekly, 32% 3 to 5 times weekly, 11% 2-3 times monthly, while the rest reported rare (4.5%) and everyday (1.2%) consumption. Logistic regression showed that increased fish consumption (>3 times/week versus never/rare) was inversely associated with the odds of having GDS greater the median value (i.e., 4) (odds  ratio = 0.34, 95% CI: 0.19, 0.61), after controlling for several cofounders. Conclusion. Frequent fish consumption in elderly seems to moderate depression mood. PMID:21197433

  3. Is it appropriate to composite fish samples for mercury trend monitoring and consumption advisories?

    PubMed

    Gandhi, Nilima; Bhavsar, Satyendra P; Gewurtz, Sarah B; Drouillard, Ken G; Arhonditsis, George B; Petro, Steve

    2016-03-01

    Monitoring mercury levels in fish can be costly because variation by space, time, and fish type/size needs to be captured. Here, we explored if compositing fish samples to decrease analytical costs would reduce the effectiveness of the monitoring objectives. Six compositing methods were evaluated by applying them to an existing extensive dataset, and examining their performance in reproducing the fish consumption advisories and temporal trends. The methods resulted in varying amount (average 34-72%) of reductions in samples, but all (except one) reproduced advisories very well (96-97% of the advisories did not change or were one category more restrictive compared to analysis of individual samples). Similarly, the methods performed reasonably well in recreating temporal trends, especially when longer-term and frequent measurements were considered. The results indicate that compositing samples within 5cm fish size bins or retaining the largest/smallest individuals and compositing in-between samples in batches of 5 with decreasing fish size would be the best approaches. Based on the literature, the findings from this study are applicable to fillet, muscle plug and whole fish mercury monitoring studies. The compositing methods may also be suitable for monitoring Persistent Organic Pollutants (POPs) in fish. Overall, compositing fish samples for mercury monitoring could result in a substantial savings (approximately 60% of the analytical cost) and should be considered in fish mercury monitoring, especially in long-term programs or when study cost is a concern.

  4. Development of a single-meal fish consumption advisory for methyl mercury

    SciTech Connect

    Ginsberg, G.L.; Toal, B.F.

    2000-02-01

    Methyl mercury (meHg) contamination of fish is the leading cause of fish consumption advisories in the US. These advisories have focused upon repeated or chronic exposure, whereas risks during pregnancy may also exist from a single-meal exposure if the fish tissue concentration is high enough. In this study, acute exposure to meHg from a single fish meal was analyzed by using the one-compartment meHg biokinetic model to predict maternal hair concentrations. These concentrations were evaluated against the mercury hair concentration corresponding to the US Environmental Protection Agency's reference dose (RfD), which is intended to protect against neurodevelopmental effects. The one-compartment model was validated against blood concentrations from three datasets in which human subjects ingested meHg in fish, either as a single meal or multiple meals. Model simulations of the single-meal scenario at different fish meHg concentrations found that concentrations of 2.0 ppm or higher can be associated with maternal hair concentrations elevated above the RfD level for days to weeks during gestation. A single-meal fish concentration cutoff of {ge} 2.0 ppm is an important consideration, especially because this single high exposure event might be in addition to a baseline meHg body burden from other types of fish consumption. This type of single-meal advisory requires that fish sampling programs provide data for individual rather than composited fish, and take into account seasonal differences that may exist in fish concentrations.

  5. Fish consumption and risk of gastrointestinal cancers: A meta-analysis of cohort studies

    PubMed Central

    Yu, Xiao-Feng; Zou, Jian; Dong, Jie

    2014-01-01

    AIM: To assess quantitatively the relationship between fish intake and the incidence of gastrointestinal cancers in a meta-analysis of cohort studies. METHODS: We searched MEDLINE, Embase, Science Citation Index Expanded, and the bibliographies of retrieved articles. Prospective cohort studies were included if they reported relative risks (RRs) and corresponding 95% confidence intervals (CIs) of various cancers with respect to fish intake. When RRs were not available in the published article, they were computed from the exposure distributions. Two investigators extracted the data independently and discrepancies were resolved by discussion with a third investigator. We performed random-effect meta-analyses and meta-regressions of study-specific incremental estimates to determine the risk of cancer associated with a 20-g/d increment of fish consumption. RESULTS: Forty-two studies, comprising 27 independent cohorts, met our inclusion criteria. The studies included 2325040 participants and 24115 incident cases of gastrointestinal cancer, with an average follow-up of 13.6 years. Compared with individuals who did not eat, or seldom ate, fish, the pooled RR of gastrointestinal cancers was 0.93 (95%CI: 0.88-0.98) for regular fish consumers, 0.94 (0.89-0.99) for low to moderate fish consumers, and 0.91 (0.84-0.97) for high fish consumers. Overall, a 20-g increase in fish consumption per day was associated with a 2% reduced risk of gastrointestinal cancers (RR = 0.98; 95%CI: 0.96-1.01). In subgroup analyses, we noted that fish consumption was associated with reduced risk of colorectal (RR = 0.93; 95%CI: 0.87-0.99; P < 0.01), esophageal (RR = 0.91; 95%CI: 0.83-0.99; P < 0.05) and hepatocellular cancers (RR = 0.71; 95%CI: 0.48-0.95; P < 0.01). CONCLUSION: This meta-analysis suggested that fish consumption may reduce total gastrointestinal cancer incidence. Inverse relationships were also detected between fish consumption and specific types of cancers. PMID:25386090

  6. Biomass of deepwater demersal forage fishes in Lake Huron, 1994-2007: Implications for offshore predators

    USGS Publications Warehouse

    Roseman, E.F.; Riley, S.C.

    2009-01-01

    We estimated the biomass of deepwater demersal forage fishes (those species common in the diets of lake trout and Chinook salmon) in Lake Huron during the period 1994-2007. The estimated total lake-wide biomass of deepwater demersal fishes in 2007 was reduced by 87 percent of that observed in 1994. Alewife biomass remained near the record low observed in 2004. Biomass of young-of-the-year rainbow smelt was at a record high in 2005, but little recruitment appears to have occurred in 2006 or 2007. Record-high estimates of young-of-the-year bloater biomass were observed in 2005 and 2007, and an increase in the biomass of adult bloater in 2007 suggests that some recruitment may be occurring. The biomass of other potential deepwater demersal forage fish species (sculpins, ninespine stickleback, trout-perch and round goby) has also declined since 1994 and remained low in 2007. The forage fish community in 2007 was dominated by small (< 120 mm) bloater and rainbow smelt. These results suggest that lake trout and Chinook salmon in Lake Huron may face nutritional stress in the immediate future.

  7. A RAD-based phylogenetics for Orestias fishes from Lake Titicaca.

    PubMed

    Takahashi, Tetsumi; Moreno, Edmundo

    2015-12-01

    The fish genus Orestias is endemic to the Andes highlands, and Lake Titicaca is the centre of the species diversity of the genus. Previous phylogenetic studies based on a single locus of mitochondrial and nuclear DNA strongly support the monophyly of a group composed of many of species endemic to the Lake Titicaca basin (the Lake Titicaca radiation), but the relationships among the species in the radiation remain unclear. Recently, restriction site-associated DNA (RAD) sequencing, which can produce a vast number of short sequences from various loci of nuclear DNA, has emerged as a useful way to resolve complex phylogenetic problems. To propose a new phylogenetic hypothesis of Orestias fishes of the Lake Titicaca radiation, we conducted a cluster analysis based on morphological similarities among fish samples and a molecular phylogenetic analysis based on RAD sequencing. From a morphological cluster analysis, we recognised four species groups in the radiation, and three of the four groups were resolved as monophyletic groups in maximum-likelihood trees based on RAD sequencing data. The other morphology-based group was not resolved as a monophyletic group in molecular phylogenies, and some members of the group were diverged from its sister group close to the root of the Lake Titicaca radiation. The evolution of these fishes is discussed from the phylogenetic relationships.

  8. The Role of Fish Communities in Water Quality Management of a Large Shallow Lake

    NASA Astrophysics Data System (ADS)

    Tátrai, István; Paulovits, Gábor; Mátyás, Kálmán; Korponai, János

    2003-09-01

    Management measures of Lake Balaton such as wetland reconstruction at the main inflow to the lake along with the unplanned commercial fishery led to great changes in the density and biomass of fish populations. There was no significant difference in CPUE data between the two, eastern and western, basins. Biomass of total fish stock in Lake Balaton has decreased substantially, 2-3 times between 1991-1999, and ranges between 120-194 kg ha-1. Bottom-up effects are more important than the top-down effects due to the impact of internal nutrient load. Changes in the biomass and thus the activity of omnivorous fish in the lake lowered the intensity of various indirect effects and feedback mechanisms causing changes in the nutrient metabolism of the lake. Intensified fishery effort in Lake Balaton did not result in an increased stock of piscivores. The ratio of piscivores and omnivores remained at 5% during the whole study period. Despite this low piscivores to omnivores ratio, the water quality has improved in all basins.

  9. Temporal and spatial variation of fish assemblages in Dianshan Lake, Shanghai, China

    NASA Astrophysics Data System (ADS)

    Hu, Zhongjun; Wang, Siqing; Wu, Hao; Chen, Qingjiang; Ruan, Renliang; Chen, Liqiao; Liu, Qigen

    2014-07-01

    Using multi-mesh gillnets and trawls, the fish communities in Dianshan Lake at 6 stations from Oct. 2009 to Jul. 2010 were investigated seasonally to reveal the biodiversity and its spatial and temporal distribution patterns. The long-term changes in their structural characteristics were then analyzed to identify the main influencing factors and several measures for lake restoration were put forward. Thirty six species, belonging to 9 family and 30 genera, were collected, amongst which, the order Cypriniformes accounted for 61.1% of the total species number. In terms of importance value, Cypriniformes was the predominant group, Coilia nasus the dominant species, while Cyprinus carpio and Rhinogobius giurinus were the subdominant taxa. The community types did not differ among stations, but between seasons. There were no significant differences between seasons and among stations in species diversity, but richness differed both spatially and seasonally. Along with the process of eutrophication and the drastic reduction of the area colonized by macrophytes from 1959 to 2009-2010, the fish diversity declined markedly, and species numbers of herbivores and piscivores declined proportionately more than those of invertivores, omnivores, and planktivores. The decline of potamophilus and river-lake migratory fish was more marked than those of sedentary, river-sea migratory, and estuarine fishes. Eutrophication concomitant with sharp reduction of macrophyte area and overfishing may be the main reasons for the decline in fish diversity in Dianshan Lake.

  10. Comparison of fish assemblages in two disjoined segments of an oxbow lake in relation to connectivity

    USGS Publications Warehouse

    Dembkowski, Daniel J.; Miranda, Leandro E.

    2011-01-01

    Disconnection between adjacent habitat patches is one of the most notable factors contributing to the decreased biotic integrity of global ecosystems. Connectivity is especially threatened in river–floodplain ecosystems in which channel modifications have disrupted the lateral links between the main river channel and floodplain lakes. In this study, we examined the interaction between the interconnectedness of floodplain lakes and main river channels and fish assemblage descriptors. Fish assemblages in two segments of an oxbow lake, one connected to and the other isolated from the Yazoo River, Mississippi, were estimated with daytime boat electrofishing during 2007–2010. The frequency of connection for the connected segment ranged from zero to seven individual events per year (mean, ∼2). The timing of most connection events reflected regional precipitation patterns. Greater species richness, diversity, and evenness were observed in the connected segment. Additionally, the connected segment had a greater abundance of piscivores and periodic life history strategists. All fishes collected solely in the connected segment were typically riverine in nature, whereas fishes collected only in the disconnected segment were more lacustrine adapted. These results suggest that periodic connection and the associated habitat heterogeneity that it provides are important for maintaining fish species richness and diversity in large-river floodplain lakes. We suggest that maintenance or restoration of connection be an integral part of fluvial ecosystem management plans.

  11. Studies of the limnology, fish populations, and fishery of Turquoise Lake, Colorado - 1979-80

    SciTech Connect

    Nesler, T.P.

    1981-07-01

    Turquoise Lake is one of the primary storage reservoirs in the Fryingpan-Arkansas Water Project and provides supplementary water by conduit to the MT. Elbert Forebay-Twin Lakes system for pump-back storage power generation. The reservoir may be characterized as a dimictic, cold-water lake that is well oxygenated, relatively unbuffed, and slightly acidic. The lake may be classified as oligotrophic on the basis of total dissolved solids, algal nutrients (N-P), and chlorophyll concentrations. Depletion of dissolved oxygen occurs regularly in the hypolimnion during late summer and late winter. Turquoise Lake is limnologically similar to Twin Lakes (Colo.) in most respects. Data contained in this report are useful to those interested in the limnology of high mountain lakes, including physical-chemical parameters, chlorophyll, plankton, and fish populations. Turquoise Lake provides source water to the Mt. Elbert forebay. Thus the baseline data provided here will be helpful in assessing the effects of pumped-storage powerplant operation on the limnology of Twin Lakes, Colo.

  12. Sensitivity of fish density estimates to standard analytical procedures applied to Great Lakes hydroacoustic data

    USGS Publications Warehouse

    Kocovsky, Patrick M.; Rudstam, Lars G.; Yule, Daniel L.; Warner, David M.; Schaner, Ted; Pientka, Bernie; Deller, John W.; Waterfield, Holly A.; Witzel, Larry D.; Sullivan, Patrick J.

    2013-01-01

    Standardized methods of data collection and analysis ensure quality and facilitate comparisons among systems. We evaluated the importance of three recommendations from the Standard Operating Procedure for hydroacoustics in the Laurentian Great Lakes (GLSOP) on density estimates of target species: noise subtraction; setting volume backscattering strength (Sv) thresholds from user-defined minimum target strength (TS) of interest (TS-based Sv threshold); and calculations of an index for multiple targets (Nv index) to identify and remove biased TS values. Eliminating noise had the predictable effect of decreasing density estimates in most lakes. Using the TS-based Sv threshold decreased fish densities in the middle and lower layers in the deepest lakes with abundant invertebrates (e.g., Mysis diluviana). Correcting for biased in situ TS increased measured density up to 86% in the shallower lakes, which had the highest fish densities. The current recommendations by the GLSOP significantly influence acoustic density estimates, but the degree of importance is lake dependent. Applying GLSOP recommendations, whether in the Laurentian Great Lakes or elsewhere, will improve our ability to compare results among lakes. We recommend further development of standards, including minimum TS and analytical cell size, for reducing the effect of biased in situ TS on density estimates.

  13. Benefits versus risks associated with consumption of fish and other seafood.

    PubMed

    Bushkin-Bedient, Sheila; Carpenter, David O

    2010-01-01

    Fish provide nutrition for much of the world's population, and when not contaminated with chemicals, fish is a very good food. A major benefit of fish is that they are high in polyunsaturated fatty acids (PUFAs), low in saturated fat, and they contain other critical nutrients. Much of the benefit of fish consumption derives from their high levels of long chain omega-3 PUFAs, which are produced by aquatic microorganisms and bioconcentrate in the aquatic food supply. The PUFAs are essential, in that humans and other vertebrates are not able to synthesize them and therefore must obtain them from the diet. The PUFAs particularly concentrate in the nervous system, alter immune system function reduce serum triglyceride levels and have been reported to reduce the risk of sudden death after a myocardial infarction. But the problem is that most fish have at least some degree of chemical contamination with methylmercury, (which binds to muscle) and/or with persistent organic pollutants such as dioxins, polychlorinated biphenyls, polybrominated diphenyl ethers, chlorinated pesticides (which concentrate in fish fat). These chemicals have adverse effects on nervous system function, modulate the immune system, and are associated with elevations in risk of cardiovascular disease. Thus the question of benefits and risk from fish consumption is complex but very important.

  14. Hair mercury levels in pregnant women in Mahshahr, Iran: fish consumption as a determinant of exposure.

    PubMed

    Salehi, Zohreh; Esmaili-Sari, Abbas

    2010-09-15

    MeHg is a well-documented neurotoxicant even at low levels of exposure. Developing brain, in particular, is vulnerable to that. Through bioaccumulating to differing degrees in various fish species, it can have serious adverse effects on the development and functioning of the human central nervous system, especially during prenatal exposure. Therefore, the purpose of this study was to investigate mercury concentration in hair samples of pregnant women living in Mahshahr located in Khuzestan province, Iran. It assessed the association between fish consumption and specific characteristics that can influence exposure. From April to June 2008, 149 pregnant women were invited to participate in this study. An interview administered questionnaire was used to collect information about age, body weight, height, fish (fresh, canned and shrimp) consumption, pregnancy stage, residence duration, education level, family income and number of dental amalgam fillings. The obtained results showed that the geometric mean and range for hair total Hg concentration was 3.52 microg/g (0.44-53.56 microg/g). About 5.4% of mothers had hair total Hg levels in excess of 10 microg/g. Maternal hair mercury level was less than threshold level of WHO (5 microg/g). As expected, there was a clear increase in hair Hg with reported fresh marine fish consumption (p=0.04). The highest mean for hair mercury level in a group who consumed fish several times per week, was 4.93 microg/g. Moreover, a significant effect of age and residential time on Hg concentration in the hair of the women was found. Pregnant women in Mahshahr consumed large amounts of fish; consequently, most of their offspring were prenatally exposed to moderately high levels of mercury. The results found suggest that pregnant women should decrease their fish consumption.

  15. Adaptive divergence between lake and stream populations of an East African cichlid fish.

    PubMed

    Theis, Anya; Ronco, Fabrizia; Indermaur, Adrian; Salzburger, Walter; Egger, Bernd

    2014-11-01

    Divergent natural selection acting in different habitats may build up barriers to gene flow and initiate speciation. This speciation continuum can range from weak or no divergence to strong genetic differentiation between populations. Here, we focus on the early phases of adaptive divergence in the East African cichlid fish Astatotilapia burtoni, which occurs in both Lake Tanganyika (LT) and inflowing rivers. We first assessed the population structure and morphological differences in A. burtoni from southern LT. We then focused on four lake-stream systems and quantified body shape, ecologically relevant traits (gill raker and lower pharyngeal jaw) as well as stomach contents. Our study revealed the presence of several divergent lake-stream populations that rest at different stages of the speciation continuum, but show the same morphological and ecological trajectories along the lake-stream gradient. Lake fish have higher bodies, a more superior mouth position, longer gill rakers and more slender pharyngeal jaws, and they show a plant/algae and zooplankton-biased diet, whereas stream fish feed more on snails, insects and plant seeds. A test for reproductive isolation between closely related lake and stream populations did not detect population-assortative mating. Analyses of F1 offspring reared under common garden conditions indicate that the detected differences in body shape and gill raker length do not constitute pure plastic responses to different environmental conditions, but also have a genetic basis. Taken together, the A. burtoni lake-stream system constitutes a new model to study the factors that enhance and constrain progress towards speciation in cichlid fishes.

  16. Contaminant effects on Great Lakes' fish-eating birds: a population perspective

    USGS Publications Warehouse

    Heinz, G.H.; Kendall, Ronald J.; Dickerson, Richard L.; Giesy, John P.; Suk, William P.

    1998-01-01

    Preventing environmental contaminants from reducing wildlife populations is the greatest concern in wildlife toxicology. In the Great Lakes, environmental contaminants have a history of reducing populations of many species of fish-eating birds. Endocrine effects may have contributed to declines in fish-eating bird populations, but the overriding harm was caused by DDE-induced eggshell thinning. Toxic effects may still be occurring today, but apparently they are not of a sufficient magnitude to depress populations of most fish-eating birds. Once DDE levels in the Great Lakes declined, eggshells of birds began to get thicker and reproductive success improved. Populations of double-crested cormorants (Phalacrocorax auritus) and ring-billed gulls (Larus delawarensis) have increased dramatically since the bans on DDT and other organochlorine pesticides. Bald eagles (Haliaeetus leucocephalus) are still not reproducing at a normal rate along the shores of the Great Lakes, but success is much improved compared to earlier records when eggshell thinning was worse. Other species, such as herring gulls (Larus argentatus) and black-crowned night-herons (Nycticorax nycticorax), seem to be having improved reproductive success, but data on Great Lakes'-wide population changes are incomplete. Reproductive success of common terns (Sterna hirundo), Caspian terns (Sterna caspia), and Forster's terns (Sterna forsteri) seems to have improved in recent years, but, again, data on population changes are not very complete, and these birds face many habitat related problems as well as contaminant problems. Although contaminants are still producing toxic effects, and these effects may include endocrine disfunction, fish-eating birds in the Great Lakes seem to be largely weathering these effects, at least as far as populations are concerned. A lack of obvious contaminant effects on populations of fish-eating birds in the Great Lakes, however, should not be equated with a lack of any harm to

  17. A Kinetic Study of Accumulation and Elimination of Microcystin-LR in Yellow Perch (Perca Flavescens) Tissue and Implications for Human Fish Consumption

    PubMed Central

    Dyble, Julianne; Gossiaux, Duane; Landrum, Peter; Kashian, Donna R.; Pothoven, Steven

    2011-01-01

    Fish consumption is a potential route of human exposure to the hepatotoxic microcystins, especially in lakes and reservoirs that routinely experience significant toxic Microcystis blooms. Understanding the rates of uptake and elimination for microcystins as well as the transfer efficiency into tissues of consumers are important for determining the potential for microcystins to be transferred up the food web and for predicting potential human health impacts. The main objective of this work was to conduct laboratory experiments to investigate the kinetics of toxin accumulation in fish tissue. An oral route of exposure was employed in this study, in which juvenile yellow perch (Perca flavescens) were given a single oral dose of 5 or 20 μg of microcystin-LR (MC-LR) via food and accumulation in the muscle, liver, and tank water were measured over 24 h. Peak concentrations of the water soluble fraction of microcystin were generally observed 8–10 h after dosing in the liver and after 12–16 h in the muscle, with a rapid decline in both tissues by 24 h. Up to 99% of the total recoverable (i.e., unbound) microcystin was measured in the tank water by 16 h after exposure. The relatively rapid uptake and elimination of the unbound fraction of microcystin in the liver and muscle of juvenile yellow perch within 24 h of exposure indicates that fish consumption may not be a major route of human exposure to microcystin, particularly in the Great Lakes. PMID:22363240

  18. Group B Streptococcus Sequence Type 283 Disease Linked to Consumption of Raw Fish, Singapore

    PubMed Central

    Rajendram, Priyanka; Mar Kyaw, Win; Ho, Hanley; Chen, Wen Kai; Lin, Raymond; Pratim, De Partha; Badaruddin, Hishamuddin; Ang, Brenda; Barkham, Timothy; Chow, Angela

    2016-01-01

    An outbreak of invasive group B Streptococcus (GBS) disease occurred in Singapore in mid-2015. We conducted a case–control study of 22 adults with invasive GBS infections during June 21–November 21, 2015. Consumption of raw fish was strongly associated with invasive sequence type 283 infections, but not with non–sequence type 283 infections. PMID:27767905

  19. Fish Consumption in Connecticut, Florida, Minnesota, and North Dakota (Final Report)

    EPA Science Inventory

    In August 2013, EPA announced the availability of the final report,Fish Consumption in Connecticut, Florida, Minnesota, and North Dakota. Many state and local health agencies throughout the United States conduct area-specific surveys that monitor and evaluate contaminant ...

  20. Environmental Health Risk Communication: Assessing Levels of Fish-Consumption Literacy among Selected Southeast Asians

    ERIC Educational Resources Information Center

    Ratnapradipa, Dhitinut; Getz, Thomas D.; Zarcadoolas, Christina; Panzara, Anthony D.; Esposito, Valerie; Wodika, Alicia B.; Caron, Colleen; Migliore, Beverly; Quilliam, Daniela N.

    2010-01-01

    Limited resources have led to a lack of comprehensive state outreach strategies that are geared for non-English speaking constituencies. The investigators worked with Southeast Asian communities in Rhode Island to determine perceptions and levels of trust with various health authorities providing health messaging about fish-consumption practices.…

  1. A synthesis of ecological and fish-community changes in Lake Ontario, 1970-2000

    USGS Publications Warehouse

    Mills, E.L.; Casselman, J.M.; Dermott, R.; Fitzsimons, J.D.; Gal, G.; Holeck, K. T.; Hoyle, J.A.; Johannsson, O.E.; Lantry, B.F.; Makarewicz, J.C.; Millard, E.S.; Munawar, I.F.; Munawar, M.; O'Gorman, R.; Owens, R.W.; Rudstam, L. G.; Schaner, T.; Stewart, T.J.

    2005-01-01

    We assessed stressors associated with ecological and fishcommunity changes in Lake Ontario since 1970, when the first symposium on Salmonid Communities in Oligotrophic Lakes (SCOL I) was held (J. Fish. Res. Board Can. 29: 613-616). Phosphorus controls implemented in the early 1970s were undeniably successful; lower food-web studies showed declines in algal abundance and epilimnetic zooplankton production and a shift in pelagic primary productivity toward smaller organisms. Stressors on the fish community prior to 1970 such as exploitation, sea lamprey (Petromyzon marinus) predation, and effects of nuisance populations of alewife (Alosa pseudoharengus) were largely ameliorated by the 1990s. The alewife became a pivotal species supporting a multi-million-dollar salmonid sport fishery, but alewife-induced thiamine deficiency continued to hamper restoration and sustainability of native lake trout (Salvelinus namaycush). Expanding salmonine populations dependent on alewife raised concerns about predator demand and prey supply, leading to reductions in salmonine stocking in the early 1990s. Relaxation of the predation impact by alewives and their shift to deeper water allowed recovery of native fishes such as threespine stickleback (Gasterosteus aculeatus) and emerald shiner (Notropis atherinoides). The return of the Lake Ontario ecosystem to historical conditions has been impeded by unplanned introductions. Establishment of Dreissena spp. led to increased water clarity and increased vectoring of lower trophic-level production to benthic habitats and contributed to the collapse of Diporeia spp. populations, behavioral modifications of key fish species, and the decline of native lake whitefish (Coregonus clupeaformis). Despite reduced productivity, exotic-species introductions, and changes in the fish community, offshore Mysis relicta populations remained relatively stable. The effects of climate and climate change on the population abundance and dynamics of Lake Ontario

  2. A nutritional dilemma: fish consumption, mercury exposure and growth of children in Amazonian Bolivia.

    PubMed

    Benefice, Eric; Monrroy, Selma J Luna; Rodriguez, Ronald W Lopez

    2008-12-01

    To study associations between nutritional status and mercury exposure among communities of the Beni River. Cross-sectional survey of mothers and their children from 15 riverside Amerindian communities in the Beni River valley (Amazonian Bolivia). Hair mercury content (H-Hg) served as a bioindicator of mercury exposure. A total of 556 people were measured. Anthropometric indices of nutrition were calculated after measurements of stature, weight, arm circumference and subcutaneous fat folds. Indicators of lifestyle were collected: subsistence activity, fish consumption and ethnicity. The median of H-Hg was equal to 4.0 microg/g (CI 95%: 3.6 approximately 4.4). There existed a significant relationship between H-Hg and nutritional indices in 5- to 10-year-old children (F = 12.1; p < 0.0001) but not in other age groups. Fishing activity, fish consumption and ethnicity had an effect upon the variance of H-Hg. Positive relationships between nutritional status and H-Hg may be related to the high nutritional value of fish. Among women, the relationship between H-Hg and nutritional status was negative (F = 7.1; p < 0.001), but this disappeared when ethnicity and subsistence activity were taken into account. In these Amazonian communities, recommendations aimed at lowering fish consumption to prevent mercury exposure should be balanced against nutritional advantages conferred upon growing children.

  3. A dataset of fishes in and around Inle Lake, an ancient lake of Myanmar, with DNA barcoding, photo images and CT/3D models

    PubMed Central

    Kano, Yuichi; Musikasinthorn, Prachya; Iwata, Akihisa; Tun, Sein; Yun, LKC; Win, Seint Seint; Matsui, Shoko; Tabata, Ryoichi; Yamasaki, Takeshi

    2016-01-01

    Abstract Background Inle (Inlay) Lake, an ancient lake of Southeast Asia, is located at the eastern part of Myanmar, surrounded by the Shan Mountains. Detailed information on fish fauna in and around the lake has long been unknown, although its outstanding endemism was reported a century ago. New information Based on the fish specimens collected from markets, rivers, swamps, ponds and ditches around Inle Lake as well as from the lake itself from 2014 to 2016, we recorded a total of 948 occurrence data (2120 individuals), belonging to 10 orders, 19 families, 39 genera and 49 species. Amongst them, 13 species of 12 genera are endemic or nearly endemic to the lake system and 17 species of 16 genera are suggested as non-native. The data are all accessible from the document “A dataset of Inle Lake fish fauna and its distribution (http://ipt.pensoft.net/resource.do?r=inle_fish_2014-16)”, as well as DNA barcoding data (mitochondrial COI) for all species being available from the DDBJ/EMBL/GenBank (Accession numbers: LC189568–LC190411). Live photographs of almost all the individuals and CT/3D model data of several specimens are also available at the graphical fish biodiversity database (http://ffish.asia/INLE2016; http://ffish.asia/INLE2016-3D). The information can benefit the clarification, public concern and conservation of the fish biodiversity in the region. PMID:27932926

  4. Fish consumption patterns and hair mercury levels in children and their mothers in 17 EU countries.

    PubMed

    Castaño, Argelia; Cutanda, Francisco; Esteban, Marta; Pärt, Peter; Navarro, Carmen; Gómez, Silvia; Rosado, Montserrat; López, Ana; López, Estrella; Exley, Karen; Schindler, Birgit K; Govarts, Eva; Casteleyn, Ludwine; Kolossa-Gehring, Marike; Fiddicke, Ulrike; Koch, Holger; Angerer, Jürgen; Den Hond, Elly; Schoeters, Greet; Sepai, Ovnair; Horvat, Milena; Knudsen, Lisbeth E; Aerts, Dominique; Joas, Anke; Biot, Pierre; Joas, Reinhard; Jiménez-Guerrero, José A; Diaz, Gema; Pirard, Catherine; Katsonouri, Andromachi; Cerna, Milena; Gutleb, Arno C; Ligocka, Danuta; Reis, Fátima M; Berglund, Marika; Lupsa, Ioana-Rodica; Halzlová, Katarína; Charlier, Corinne; Cullen, Elizabeth; Hadjipanayis, Adamos; Krsková, Andrea; Jensen, Janne F; Nielsen, Jeanette K; Schwedler, Gerda; Wilhelm, Michael; Rudnai, Peter; Középesy, Szilvia; Davidson, Fred; Fischer, Mark E; Janasik, Beata; Namorado, Sónia; Gurzau, Anca E; Jajcaj, Michal; Mazej, Darja; Tratnik, Janja Snoj; Larsson, Kristin; Lehmann, Andrea; Crettaz, Pierre; Lavranos, Giagkos; Posada, Manuel

    2015-08-01

    The toxicity of methylmercury (MeHg) in humans is well established and the main source of exposure is via the consumption of large marine fish and mammals. Of particular concern are the potential neurodevelopmental effects of early life exposure to low-levels of MeHg. Therefore, it is important that pregnant women, children and women of childbearing age are, as far as possible, protected from MeHg exposure. Within the European project DEMOCOPHES, we have analyzed mercury (Hg) in hair in 1799 mother-child pairs from 17 European countries using a strictly harmonized protocol for mercury analysis. Parallel, harmonized questionnaires on dietary habits provided information on consumption patterns of fish and marine products. After hierarchical cluster analysis of consumption habits of the mother-child pairs, the DEMOCOPHES cohort can be classified into two branches of approximately similar size: one with high fish consumption (H) and another with low consumption (L). All countries have representatives in both branches, but Belgium, Denmark, Spain, Portugal and Sweden have twice as many or more mother-child pairs in H than in L. For Switzerland, Czech Republic, Hungary, Poland, Romania, Slovenia and Slovakia the situation is the opposite, with more representatives in L than H. There is a strong correlation (r=0.72) in hair mercury concentration between the mother and child in the same family, which indicates that they have a similar exposure situation. The clustering of mother-child pairs on basis of their fish consumption revealed some interesting patterns. One is that for the same sea fish consumption, other food items of marine origin, like seafood products or shellfish, contribute significantly to the mercury levels in hair. We conclude that additional studies are needed to assess and quantify exposure to mercury from seafood products, in particular. The cluster analysis also showed that 95% of mothers who consume once per week fish only, and no other marine products

  5. New Evidence on Variations of Human Body Burden of Methylmercury from Fish Consumption

    PubMed Central

    Canuel, René; de Grosbois, Sylvie Boucher; Atikessé, Laura; Lucotte, Marc; Arp, Paul; Ritchie, Charles; Mergler, Donna; Chan, Hing Man; Amyot, Marc; Anderson, Robin

    2006-01-01

    Epidemiologic studies commonly use mercury (Hg) level in hair as a valid proxy to estimate human exposure to methylmercury (MeHg) through fish consumption. This study presents the results yielded by a complete data set on fish consumption habits, Hg levels in edible fish resources, and corresponding Hg accumulation in hair, gathered in three distinct communities of eastern Canada. For one of these communities, the average hair Hg concentration was 14 times less than the expected value based on calculated daily oral exposure and current knowledge of MeHg metabolism. This finding could be explained by differences in specific genetic characteristics and/or interactive effects of other dietary components. PMID:16451872

  6. Atmospherically deposited PBDEs, pesticides, PCBs, and PAHs in western U.S. National Park fish: Concentrations and consumption guidelines

    USGS Publications Warehouse

    Ackerman, L.K.; Schwindt, A.R.; Simonich, S.L.M.; Koch, D.C.; Blett, T.F.; Schreck, C.B.; Kent, M.L.; Landers, D.H.

    2008-01-01

    Concentrations of polybrominated diphenyl ethers (PBDEs), pesticides, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons were measured in 136 fish from 14 remote lakes in 8 western U.S. National Parks/Preserves between 2003 and 2005 and compared to human and wildlife contaminant health thresholds. A sensitive (median detection limit, -18 pg/g wet weight), efficient (61% recovery at 8 ng/g), reproducible (4.1% relative standard deviation (RSD)), and accurate (7% deviation from standard reference material (SRM)) analytical method was developed and validated for these analyses. Concentrations of PCBs, hexachlorobenzene, hexachlorocyclohexanes, DDTs, and chlordanes in western U.S. fish were comparable to or lower than mountain fish recently collected from Europe, Canada, and Asia. Dieldrin and PBDE concentrations were higher than recent measurements in mountain fish and Pacific Ocean salmon. Concentrations of most contaminants in western U.S. fish were 1-6 orders of magnitude below calculated recreational fishing contaminant health thresholds. However, lake average contaminant concentrations in fish exceeded subsistence fishing cancer thresholds in 8 of 14 lakes and wildlife contaminant health thresholds for piscivorous birds in 1of 14 lakes. These results indicate that atmospherically deposited organic contaminants can accumulate in high elevation fish, reaching concentrations relevant to human and wildlife health. ?? 2008 American Chemical Society.

  7. Atmospherically Deposited PBDEs, Pesticides, PCBs, and PAHs in Western US National Park Fish: Concentrations and Consumption Guidelines

    PubMed Central

    Ackerman, Luke K.; Schwindt, Adam R.; Simonich, Staci L.; Koch, Dan C.; Blett, Tamara F.; Schreck, Carl B.; Kent, Michael L.; Landers, Dixon H.

    2014-01-01

    Concentrations of polybrominated diphenyl ethers (PBDEs), pesticides, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons were measured in 136 fish from 14 remote lakes in 8 western US National Parks/Preserves between 2003 and 2005 and compared to human and wildlife contaminant health thresholds. A sensitive (median detection limit −18 pg/g wet weight), efficient (61% recovery at 8 ng/g), reproducible (4.1 %RSD), and accurate (7 % deviation from SRM) analytical method was developed and validated for these analyses. Concentrations of PCBs, hexachlorobenzene, hexachlorocyclohexanes, DDTs and chlordanes in western US fish were comparable to or lower than mountain fish recently collected from Europe, Canada, and Asia. Dieldrin and PBDE concentrations were higher than recent measurements in mountain fish and Pacific Ocean salmon. Concentrations of most contaminants in western US fish were 1–6 orders of magnitude below calculated recreational fishing contaminant health thresholds. However, contaminant concentrations exceeded subsistence fishing cancer screening values in 8 of 14 lakes. Average contaminant concentrations in fish exceeded wildlife contaminant health thresholds for piscivorous mammals in 5 lakes, and piscivorous birds in all 14 lakes. These results indicate that atmospherically deposited organic contaminants can accumulate in high elevation fish, reaching concentrations relevant to human and wildlife health. PMID:18504962

  8. Probabilistic framework for assessing the arsenic exposure risk from cooked fish consumption.

    PubMed

    Ling, Min-Pei; Wu, Chiu-Hua; Chen, Szu-Chieh; Chen, Wei-Yu; Chio, Chia-Pin; Cheng, Yi-Hsien; Liao, Chung-Min

    2014-12-01

    Geogenic arsenic (As) contamination of groundwater is a major ecological and human health problem in southwestern and northeastern coastal areas of Taiwan. Here, we present a probabilistic framework for assessing the human health risks from consuming raw and cooked fish that were cultured in groundwater As-contaminated ponds in Taiwan by linking a physiologically based pharmacokinetics model and a Weibull dose-response model. Results indicate that As levels in baked, fried, and grilled fish were higher than those of raw fish. Frying resulted in the greatest increase in As concentration, followed by grilling, with baking affecting the As concentration the least. Simulation results show that, following consumption of baked As-contaminated fish, the health risk to humans is <10(-6) excess bladder cancer risk level for lifetime exposure; as the incidence ratios of liver and lung cancers are generally acceptable at risk ranging from 10(-6) to 10(-4), the consumption of baked As-contaminated fish is unlikely to pose a significant risk to human health. However, contaminated fish cooked by frying resulted in significant health risks, showing the highest cumulative incidence ratios of liver cancer. We also show that males have higher cumulative incidence ratio of liver cancer than females. We found that although cooking resulted in an increase for As levels in As-contaminated fish, the risk to human health of consuming baked fish is nevertheless acceptable. We suggest the adoption of baking as a cooking method and warn against frying As-contaminated fish. We conclude that the concentration of contaminants after cooking should be taken into consideration when assessing the risk to human health.

  9. Spatial distribution of pelagic fish larvae in the northern main basin of Lake Huron

    USGS Publications Warehouse

    Roseman, Edward F.; O'Brien, Timothy P.

    2013-01-01

    Larval fish occurrence in inshore and offshore zones in the northern main basin of Lake Huron was assessed during 2007 as part of a larger ecological examination of Lake Huron foodwebs and habitats. Day and night collections using neuston and conical nets at inshore (1.5–15 m depths) and offshore (37 and 91 m depths) locations at De Tour and Hammond Bay to assess the abundance, phenology, and spatial distribution of pelagic ichthyoplankton during spring and early summer were made. In general, densities of larval fishes were higher at De Tour than Hammond Bay during daytime neuston net collections, with the exception of Longnose Sucker, which were only collected at Hammond Bay. Lake Whitefish, Burbot, and Rainbow Smelt dominated inshore catches in early spring with Cisco, Deepwater Sculpin, Emerald Shiner, Bloater, Slimy Sculpin, Ninespine Stickleback, and Yellow Perch larvae also collected. Nighttime nearshore and offshore sampling revealed that Rainbow Smelt and Burbot larvae were present in relatively high abundances compared to inshore densities. Concentrations of larvae of deepwater demersal fishes such as Lake Whitefish and Deepwater Sculpin suggest that inshore zones in northern Lake Huron are important nursery habitats emphasizing a critical production and recruitment linkage between inshore and deepwater zones.

  10. Elevated mercury concentrations in fish in lakes in the Mackenzie River Basin: the role of physical, chemical, and biological factors.

    PubMed

    Evans, M S; Lockhart, W L; Doetzel, L; Low, G; Muir, D; Kidd, K; Stephens, G; Delaronde, J

    2005-12-01

    During the mid-1990s and through the early 2000s, researchers determined that elevated mercury concentrations were a common occurrence in predatory fish in many lakes in the Mackenzie River Basin (MRB), located in northern Canada. Here we present the results of studies investigating factors contributing to higher mercury concentrations in fish in many of these lakes. Twenty-two percent of lake trout, 33% of northern pike, and 50% of walleye populations had mean mercury concentrations >0.5 microg/g, the guideline for the commercial sale of fish. Higher mercury concentrations were strongly associated with the relatively old age of MRB predatory fish; mean age ranged from 7.6 to 24.9 years for the three species. In contrast, none of the lake trout sampled in eight lakes further south in northern Saskatchewan and Alberta had mean mercury concentrations >0.5 microg/g; fish also were younger (mean age 6 years for the 8 lakes). Mercury concentrations in MRB fish generally increased with fish length, age, and trophic feeding although the nature of these relationships varied with the lake. Mean length was a good predictor of mean mercury concentrations in walleye populations across the study lakes but not for whitefish, lake trout, and pike; age was a good predictor for lake trout and walleye. Mercury concentrations in water and invertebrates were similar to those observed in more southerly regions where fish do not have elevated mercury concentrations. Mercury concentrations tended to be higher in fish in smaller vs. larger lakes and as a probable consequence of higher summer epilimnion temperatures, which favour a higher net methylation rate, and higher mercury and methyl mercury concentrations in water which enter these lakes from the watershed. Increasing fishing pressures on MRB lakes may be a means of reducing mean fish age, improving growth rates, and decreasing mercury body burdens. Increased global warming may result in higher mercury concentrations in fish through

  11. Polychlorinated biphenyls and hexachlorocyclohexanes in sediments and fish species from the Napoleon Gulf of Lake Victoria, Uganda.

    PubMed

    Ssebugere, Patrick; Sillanpää, Mika; Kiremire, Bernard T; Kasozi, Gabriel N; Wang, Pu; Sojinu, Samuel O; Otieno, Peter O; Zhu, Nali; Zhu, Chaofei; Zhang, Haidong; Shang, Hongtao; Ren, Daiwei; Li, Yingming; Zhang, Qinghua; Jiang, Guibin

    2014-05-15

    Polychlorinated biphenyls (PCBs) and hexachlorocyclohexanes (HCHs) were analyzed in surface sediments (<30 cm depth) and two fish species: Nile perch (Lates niloticus) and Nile tilapia (Oreochromis niloticus). The samples were collected from the Napoleon Gulf on the northern shore of Lake Victoria. The analysis was done using a gas chromatograph (GC) coupled to a high resolution mass spectrometer for PCBs and a GC equipped with an electron capture detector for HCHs. Total (Σ) PCBs in the muscles of fish varied widely with mean values ranging from 41 to 670 pg g(-1) lipid weight (lw). The PCB levels in L. niloticus were significantly greater than those in O. niloticus. The large variability observed in the data was attributed to differences in feeding habits and trophic levels. While O. niloticus is a filter-eating fish species feeding mainly on phytoplankton and zooplankton, L. niloticus have predatory feeding behaviors and prefer a diet of live fish and, therefore, are more prone to bio-accumulate contaminants. The mean PCB concentrations in the sediments varied from 362 to 848 pg g(-1) dry weight. Variations in PCB levels were observed from one study site to another, this was attributed to the nature and particle size of the sediments. HCH isomers were detected in fish at mean concentrations of up to 45,900 pg g(-1) lw. The PCB and HCH concentrations were lower than those from previous studies elsewhere in literature and were below the maximum residue limits set by the European Commission and FAO/WHO Codex Alimentarius Commission, implying that the fish was fit for human consumption.

  12. Fish consumption, low-level mercury, lipids, and inflammatory markers in children.

    PubMed

    Gump, Brooks B; MacKenzie, James A; Dumas, Amy K; Palmer, Christopher D; Parsons, Patrick J; Segu, Zaneer M; Mechref, Yehia S; Bendinskas, Kestutis G

    2012-01-01

    There is considerable evidence that consuming fish has numerous health benefits, including a reduced risk of cardiovascular disease. However, fish is also the primary source of human exposure to mercury (Hg). In a cross-sectional study of 9-11 year old children (N=100), we measured fish consumption, blood lipids, total blood Hg, diurnal salivary cortisol (4 samples collected throughout the day), and performed a proteomic analysis of serum proteins using spectral count shotgun proteomics. Children who consumed fish had a significantly more atheroprotective lipid profile but higher levels of blood Hg relative to children that did not consume fish. Although the levels of blood Hg were very low in these children (M=0.77 μg/L; all but 1 participant had levels below 3.27 μg/L), increasing blood Hg was significantly associated with blunted diurnal cortisol levels. Blood Hg was also significantly associated with acute-phase proteins suggesting systemic inflammation, and several of these proteins were found to significantly reduce the association between Hg and diminished cortisol when included in the model. This study of a pediatric population is the first to document an association between blood Hg, systemic inflammation, and endocrine disruption in humans. Without a better understanding of the long-term consequences of an atheroprotective lipid profile relative to blunted diurnal cortisol and systemic inflammation, a determination of the risk-benefit ratio for fish consumption by children is not possible.

  13. Fish Consumption, Low-Level Mercury, Lipids, and Inflammatory Markers in Children

    PubMed Central

    Gump, Brooks B.; MacKenzie, James A.; Dumas, Amy K.; Palmer, Christopher D.; Parsons, Patrick J.; Segu, Zaneer M.; Mechref, Yehia S.; Bendinskas, Kestutis

    2011-01-01

    There is considerable evidence that consuming fish has numerous health benefits, including a reduced risk of cardiovascular disease. However, fish is also the primary source of human exposure to mercury (Hg). In a cross-sectional study of 9–11 year old children (N = 100), we measured fish consumption, blood lipids, total blood Hg, diurnal salivary cortisol (4 samples collected throughout the day), and performed a proteomic analysis of serum proteins using spectral count shotgun proteomics. Children that consumed fish had a significantly more atheroprotective lipid profile but higher levels of blood Hg relative to children that did not consume fish. Although the levels of blood Hg were very low in these children (M = 0.77 μg/L; all but 1 participant had levels below 3.27 μg/L), increasing blood Hg was significantly associated with blunted diurnal cortisol levels. Blood Hg was also significantly associated with acute-phase proteins suggesting systemic inflammation, and several of these proteins were found to significantly reduce the association between Hg and diminished cortisol when included in the model. This study of a pediatric population is the first to document an association between blood Hg, systemic inflammation, and endocrine disruption in humans, in a pediatric sample. Without a better understanding of the long-term consequences of an atheroprotective lipid profile relative to blunted diurnal cortisol and systemic inflammation, a determination of the risk-benefit ratio for fish consumption by children is not possible. PMID:22030286

  14. Geographic, Anthropogenic and Habitat Influences on Great Lakes Coastal Wetland Fish Assemblages

    EPA Science Inventory

    We analyzed data from coastal wetlands across all five Laurentian Great Lakes to identify patterns in fish assemblages and relationships to local habitat, watershed condition, and regional setting. NMDS ordination of electrofishing catch-per-effort data revealed an overriding ge...

  15. Response of a Diminutive Coldwater Fish to Warming in the World’s Largest Lake

    EPA Science Inventory

    Lake Superior’s 2.5 °C increase in mean summer surface water temperatures over the past 30 years is one of the greatest documented temperature increases of any habitat worldwide. We took advantage of a long-term record (1978-2010) of water temperature profiles and fish collectio...

  16. Trophic connections in Lake Superior Part I: the offshore fish community

    USGS Publications Warehouse

    Gamble, A.E.; Hrabik, T.R.; Stockwell, J.D.; Yule, D.L.

    2011-01-01

    Detailed diet linkages within the offshore (> 80 m bathymetric depth) food web of Lake Superior are currently not well identified. We used analyses of fish stomach contents to create an empirically based food web model of the Lake Superior offshore fish community. Stomachs were collected seasonally (spring, summer, and fall) from nine offshore locations in 2005, using bottom and midwater trawls. In total, 2643 stomachs representing 12 fish species were examined. The predominant fish species collected were deepwater sculpin (Myoxocephalus thompsonii), siscowet (Salvelinus namaycush siscowet), kiyi (Coregonus kiyi), and cisco (Coregonus artedi). Mysis diluviana was the most common prey item, indicating that changes in Mysis abundance could have a profound impact on the entire offshore food web. Mysis was the primary diet item of deepwater sculpin (≥ 53% by mass) and kiyi (≥ 96% by mass) regardless of depth or season. The invasive Bythotrephes was an important diet component of the pelagic cisco in summer and fall. Deepwater sculpin were the primary diet item of siscowet (≥ 52% by mass), with coregonines appearing in the diet of larger (> 400 mm) siscowet. Non-metric multidimensional scaling analysis indicated that there were no statistically significant seasonal or site-specific differences in diets of deepwater sculpin, cisco, or kiyi. Site was the primary structuring factor in siscowet diets. Generally, in Lake Superior, the diet items of the dominant offshore species did not appear to be in danger from those types of major ecological shifts occurring in the lower Laurentian Great Lakes.

  17. MERGANSER- Predicting Mercury Levels in Fish and Loons in New England Lakes

    EPA Science Inventory

    MERGANSER (MERcury Geo-spatial AssesmentS for the New England Region) is an empirical least squares multiple regression model using atmospheric deposition of mercury (Hg) and readily obtainable lake and watershed features to predict fish and common loon Hg (as methyl mercury) in ...

  18. BILIARY PAH METABOLITES AS A BIOLOGICAL INDICATOR OF FISH EXPOSURE IN TRIBUTARIES OF LAKE ERIE

    EPA Science Inventory

    Biliary polynuclear aromatic hydrocarbons (PAH) metabolites have been studied as a biological indicator of fish exposure to PAHs since the mid 1980's. Brown bullheads were collected from the following Lake Erie tributaries: Buffalo River (BUF), Niagara River at Love Canal (NIA)...

  19. Measurement error associated with surveys of fish abundance in Lake Michigan

    USGS Publications Warehouse

    Krause, Ann E.; Hayes, Daniel B.; Bence, James R.; Madenjian, Charles P.; Stedman, Ralph M.

    2002-01-01

    In fisheries, imprecise measurements in catch data from surveys adds uncertainty to the results of fishery stock assessments. The USGS Great Lakes Science Center (GLSC) began to survey the fall fish community of Lake Michigan in 1962 with bottom trawls. The measurement error was evaluated at the level of individual tows for nine fish species collected in this survey by applying a measurement-error regression model to replicated trawl data. It was found that the estimates of measurement-error variance ranged from 0.37 (deepwater sculpin, Myoxocephalus thompsoni) to 1.23 (alewife, Alosa pseudoharengus) on a logarithmic scale corresponding to a coefficient of variation = 66% to 156%. The estimates appeared to increase with the range of temperature occupied by the fish species. This association may be a result of the variability in the fall thermal structure of the lake. The estimates may also be influenced by other factors, such as pelagic behavior and schooling. Measurement error might be reduced by surveying the fish community during other seasons and/or by using additional technologies, such as acoustics. Measurement-error estimates should be considered when interpreting results of assessments that use abundance information from USGS-GLSC surveys of Lake Michigan and could be used if the survey design was altered. This study is the first to report estimates of measurement-error variance associated with this survey.

  20. Restoring piscivorous fish populations in the Laurentian Great Lakes causes seabird dietary change

    USGS Publications Warehouse

    Hebert, C.E.; Weseloh, D.V.C.; Idrissi, A.; Arts, M.T.; O'Gorman, R.; Gorman, O.T.; Locke, B.; Madenjian, C.P.; Roseman, E.F.

    2008-01-01

    Ecosystem change often affects the structure of aquatic communities thereby regulating how much and by what pathways energy and critical nutrients flow through food webs. The availability of energy and essential nutrients to top predators such as seabirds that rely on resources near the water's surface will be affected by changes in pelagic prey abundance. Here, we present results from analysis of a 25-year data set documenting dietary change in a predatory seabird from the Laurentian Great Lakes. We reveal significant declines in trophic position and alterations in energy and nutrient flow over time. Temporal changes in seabird diet tracked decreases in pelagic prey fish abundance. As pelagic prey abundance declined, birds consumed less aquatic prey and more terrestrial food. This pattern was consistent across all five large lake ecosystems. Declines in prey fish abundance may have primarily been the result of predation by stocked piscivorous fishes, but other lake-specific factors were likely also important. Natural resource management activities can have unintended consequences for nontarget ecosystem components. Reductions in pelagic prey abundance have reduced the capacity of the Great Lakes to support the energetic requirements of surface-feeding seabirds. In an environment characterized by increasingly limited pelagic fish resources, they are being offered a Hobsonian choice: switch to less nutritious terrestrial prey or go hungry. ?? 2008 by the Ecological Society of America.

  1. Ecological tracers reveal resource convergence among prey fish species in a large lake ecosystem

    USGS Publications Warehouse

    Paterson, Gord; Rush, Scott A.; Arts, Michael T.; Drouillard, Ken G.; Haffner, G. Doug; Johnson, Tim B.; Lantry, Brian F.; Hebert, Craig E.; McGoldrick, Daryl J.; Backus, Sean M.; Fisk, Aaron T.

    2014-01-01

    5. These results indicate a temporal convergence of the food niche, whereas food partitioning has historically supported the coexistence of prey fish species in Lake Ontario. This convergence is consistent with changes in food-web processes associated with the invasion of dreissenid mussels.

  2. Structure and stability of the midsummer fish communities in Chequamegon Bay, Lake Superior, 1973-1996

    USGS Publications Warehouse

    Hoff, M.H.; Bronte, C.R.

    1999-01-01

    We analyzed the structure and stability of the summer fish communities of Chequamegon Bay, Lake Superior, during 1973-1996 from data collected with bottom trawls at 39 stations. Fifty-three taxa were collected during the study, but we found that relative abundances for 20 taxa described most of the internal variability of the data for all taxa. Abundance data for the 20 species showed that two communities existed in the bay; one inhabited shallow water (3.0 m) whereas the other inhabited deeper water (>3.0 m). No temporal patterns of change were found in the structure of the shallow-water community, whose variation was best described by abundances of 12 taxa. The deepwater community, whose variation was best described by eight taxa, underwent three periods ofstability; 1973-1978, 1979-1988, and 1989-1996. We conclude that the shallow-water community was stable throughout the 24 years studied. Dynamics of the deepwater community were greatly affected by changes in stocking rates of lake troutSalvelinus namaycush and splake (hybrid of brook trout Salvelinus fontinalis × lake trout) and by rehabilitation of populations of lake herring Coregonus artedi and lake whitefish Coregonus clupeaformis. Information on the existence, structure, stability, and habitats of fish communities in the bay will be useful for assessing changes in those communities that result from further changes in the bay or lake ecosystems.

  3. Connectedness of land use, nutrients, primary production, and fish assemblages in oxbow lakes

    USGS Publications Warehouse

    Miranda, Leandro E.; Andrews, Caroline S.; Kroger, Robert

    2013-01-01

    We explored the strength of connectedness among hierarchical system components associated with oxbow lakes in the alluvial valley of the Lower Mississippi River. Specifically, we examined the degree of canonical correlation between land use (agriculture and forests), lake morphometry (depth and size), nutrients (total nitrogen and total phosphorus), primary production (chlorophyll-a), and various fish assemblage descriptors. Watershed (p < 0.01) and riparian (p = 0.02) land use, and lake depth (p = 0.05) but not size (p = 0.28), were associated with nutrient concentrations. In turn, nutrients were associated with primary production (p < 0.01), and primary production was associated with sunfish (Centrarchidae) assemblages (p < 0.01) and fish biodiversity (p = 0.08), but not with those of other taxa and functional guilds. Multiple chemical and biological components of oxbow lake ecosystems are connected to landscape characteristics such as land use and lake depth. Therefore, a top-down hierarchical approach can be useful in developing management and conservation plans for oxbow lakes in a region impacted by widespread landscape changes due to agriculture.

  4. High rate of prey consumption in a small predatory fish on coral reefs

    NASA Astrophysics Data System (ADS)

    Feeney, W. E.; Lönnstedt, O. M.; Bosiger, Y.; Martin, J.; Jones, G. P.; Rowe, R. J.; McCormick, M. I.

    2012-09-01

    Small piscivores are regarded as important regulators of the composition of coral reef fish communities, but few studies have investigated their predatory ecology or impact on assemblages of juvenile fishes. This study investigated the foraging ecology of a common coral reef predator, the dottyback Pseudochromis fuscus, using underwater focal animal observations. Observations were conducted at two times of year: the summer, when recruit fishes were an available food item and winter, when remaining juveniles had outgrown vulnerability to P. fuscus. During the summer, P. fuscus directed 76% of its strikes at invertebrates and 24% at recruiting juvenile fishes. When striking at fishes, P. fuscus exhibited two distinct feeding modes: an ambush (26% successful) and a pursuit mode (5% successful). Predator activity in the field peaked at midday, averaging 2.5 captures h-1 of juvenile fishes. Monitoring of activity and foraging in the laboratory over 24-h periods found that P. fuscus was a diurnal predator and was active for 13 h d-1 during the summer. The number of hours during which foraging was recorded differed greatly among individuals ( n = 10), ranging from 4 to 13 h. The number of predatory strikes did not increase with standard length, but the success rate and consumption rate of juvenile fishes did increase with size. Estimated hourly mortality on juvenile fish ranged from 0.49 fish h-1 in small P. fuscus individuals (30-39 mm standard length, SL; equating to 6.3 per 13 h day) to 2.4 fish h-1 in large P. fuscus individuals (55-65 mm SL; 30.6 per 13 h day). During the winter, P. fuscus struck at invertebrates with a similar rate to the summer period. These observations of the predatory ecology of P. fuscus support the hypothesis that in coral reef systems, small piscivores, because of their high metabolism and activity, are probably important regulators of coral reef fish community composition.

  5. Evaluating risk communication: examining target audience perceptions about four presentation formats for fish consumption health advisory information.

    PubMed

    Connelly, N A; Knuth, B A

    1998-10-01

    Information format can influence the extent to which target audiences understand and respond to risk-related information. This study examined four elements of risk information presentation format. Using printed materials, we examined target audience perceptions about: (a) reading level; (b) use of diagrams vs. text; (c) commanding versus cajoling tone; and (d) use of qualitative vs. quantitative information presented in a risk ladder. We used the risk communication topic of human health concerns related to eating noncommercial Great Lakes fish affected by chemical contaminants. Results from the comparisons of specific communication formats indicated that multiple formats are required to meet the needs of a significant percent of anglers for three of the four format types examined. Advisory text should be reviewed to ensure the reading level is geared to abilities of the target audience. For many audiences, a combination of qualitative and quantitative information, and a combination of diagrams and text may be most effective. For most audiences, a cajoling rather than commanding tone better provides them with the information they need to make a decision about fish consumption. Segmenting audiences regarding information needs and communication formats may help clarify which approaches to take with each audience.

  6. Characterization of the quality of water, bed sediment, and fish in Mittry Lake, Arizona, 2014–15

    USGS Publications Warehouse

    Hermosillo, Edyth; Coes, Alissa L.

    2017-03-01

    Water, bed-sediment, and fish sampling was conducted in Mittry Lake, Arizona, in 2014–15 to establish current water-quality conditions of the lake. The parameters of temperature, dissolved-oxygen concentration, specific conductance, and alkalinity were measured in the field. Water samples were collected and analyzed for dissolved major ions, dissolved trace elements, dissolved nutrients, dissolved organic carbon, dissolved pesticides, bacteria, and suspended-sediment concentrations. Bed-sediment and fish samples were analyzed for trace elements, halogenated compounds, total mercury, and methylmercury.U.S. Environmental Protection Agency secondary maximum contaminant levels in drinking water were exceeded for sulfate, chloride, and manganese in the water samples. Trace-element concentrations were relatively similar between the inlet, middle, and outlet locations. Concentrations for nutrients in all water samples were below the Arizona Department of Environmental Quality’s water-quality standards for aquatic and wildlife uses, and all bacteria levels were below the Arizona Department of Environmental Quality’s recommended recreational water-quality criteria. Three out of 81 pesticides were detected in the water samples.Trace-element concentrations in bed sediment were relatively consistent between the inlet, middle, and outlet locations. Lead, manganese, nickel, and zinc concentrations, however, decreased from the inlet to outlet locations. Concentrations for lead, nickel, and zinc in some bed-sediment samples exceeded consensus-based sediment-quality guidelines probable effect concentrations. Eleven out of 61 halogenated compounds were detected in bed sediment at the inlet location, whereas three were detected at the middle location, and five were detected at the outlet location. No methylmercury was detected in bed sediment. Total mercury was detected in bed sediment at concentrations below the consensus-based sediment-quality guidelines probable effect

  7. Perceptions of the risks and benefits of fish consumption: Individual choices to reduce risk and increase health benefits

    PubMed Central

    Burger, Joanna; Gochfeld, Michael

    2014-01-01

    Studies of fish consumption often focus on awareness of and adherence to advisories, how much fish people eat, and contaminant levels in those fish. This paper examines knowledge and accuracy of risks and benefits of fish consumption among fishers and other recreationists in the New York Bight, indicative of whether they could make sound dietary decisions. While most respondents knew about health risks (70%) and benefits (94%) of consuming fish, far fewer could name specific risks and benefits. Less than 25% of respondents mentioned mercury and less than 15% mentioned that pregnant women and children were at risk. Far fewer people mentioned polychlorinated biphenyls (PCBs). Nearly 70% said it was healthy to eat fish, and 45% were aware that fish were rich in healthful oils. Despite the lack of details about what specific risks and benefits of fish, well over a third did not feel they needed more information. Other respondents had basic questions, but did not pose specific questions about the fish they caught or ate that would have clarified their individual risk-balancing decisions. Knowledge of which fish were high in contaminants did not match the mercury or PCB levels in those fish. There was a disconnect between the information base about specific risks and benefits of fish consumption, levels of mercury and PCBs in fish, and the respondent’s desire for more information. These data indicate that respondents did not have enough accurate information about contaminants in fish to make informed risk-balancing decisions. PMID:19193369

  8. Quantifying multi-habitat support of Great Lakes fishes

    EPA Science Inventory

    Recent advances in trophic ecology have revealed the interconnectedness of diverse habitats in support of aquatic food webs. Understanding the degree to which different habitats support fish can be valuable for fisheries management and ecosystem protection. For example, stable is...

  9. A Longitudinal Study of Mercury Exposure Associated with Consumption of Freshwater Fish from a Reservoir in Rural South Central USA

    PubMed Central

    Dong, Zhao; Jim, Rebecca C.; Hatley, Earl L.; Backus, Ann S. N.; Shine, James P.; Spengler, John D.; Schaider, Laurel A.

    2015-01-01

    Methylmercury (MeHg) exposure through fish consumption is a worldwide health concern. Saltwater fish account for most dietary MeHg exposure in the general U.S. population, but less is known about seasonal variations in MeHg exposure and fish consumption among millions of freshwater anglers. This longitudinal study examined associations between MeHg exposure and fish consumption in a rural, low-income population relying on a freshwater reservoir (Oklahoma, USA) for recreational and subsistence fishing. We interviewed 151 participants, primarily anglers and their families, seasonally for one year using 90-day recall food frequency questionnaires to assess general and species-specific fish consumption, and tested hair biomarker samples for total mercury (THghair). Mean THghair was 0.27 μg/g (n=595, range: 0.0044–3.1 μg/g), with 4% of participants above U.S. EPA's guideline for women of childbearing age and children. Mean fish consumption was 58 g/d (95% CI: 49–67 g/d), within the range previously reported for recreational freshwater anglers and above the national average. Unlike the general U.S. population, freshwater species contributed the majority of fish consumption (69%) and dietary Hg exposure (60%) among participants, despite relatively low THg in local fish. THghair increased with fish consumption, age, and education, and was higher among male participants and lowest in winter. Our results suggest that future studies of anglers should consider seasonality in fish consumption and MeHg exposure and include household members who share their catch. Efforts to evaluate benefits of reducing Hg emissions should consider dietary patterns among consumers of fish from local freshwater bodies. PMID:25460632

  10. Steel Creek fish: L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1987

    SciTech Connect

    Paller, M.H.; Heuer, J.H.; Kissick, L.A.

    1988-03-01

    Fish samples were collected from Steel Creek during 1986 and 1987 following the impoundment of the headwaters of the stream to form L-Lake, a cooling reservoir for L-Reactor which began operating late in 1985. Electrofishing and ichthyoplankton sample stations were located throughout the creek. Fykenetting sample stations were located in the creek mouth and just above the Steel Creek swamp. Larval fish and fish eggs were collected with 0.5 m plankton nets. Multivariate analysis of the electrofishing data suggested that the fish assemblages in Steel Creek exhibited structural differences associated with proximity to L-Lake, and habitat gradients of current velocity, depth, and canopy cover. The Steel Creek corridor, a lotic reach beginning at the base of the L-Lake embankment was dominated by stream species and bluegill. The delta/swamp, formed where Steel Creek enters the Savannah River floodplain, was dominated by fishes characteristic of slow flowing waters and heavily vegetated habitats. The large channel draining the swamp supported many of the species found in the swamp plus riverine and anadromous forms.

  11. Climate change expands the spatial extent and duration of preferred thermal habitat for lake Superior fishes.

    PubMed

    Cline, Timothy J; Bennington, Val; Kitchell, James F

    2013-01-01

    Climate change is expected to alter species distributions and habitat suitability across the globe. Understanding these shifting distributions is critical for adaptive resource management. The role of temperature in fish habitat and energetics is well established and can be used to evaluate climate change effects on habitat distributions and food web interactions. Lake Superior water temperatures are rising rapidly in response to climate change and this is likely influencing species distributions and interactions. We use a three-dimensional hydrodynamic model that captures temperature changes in Lake Superior over the last 3 decades to investigate shifts in habitat size and duration of preferred temperatures for four different fishes. We evaluated habitat changes in two native lake trout (Salvelinus namaycush) ecotypes, siscowet and lean lake trout, Chinook salmon (Oncorhynchus tshawytscha), and walleye (Sander vitreus). Between 1979 and 2006, days with available preferred thermal habitat increased at a mean rate of 6, 7, and 5 days per decade for lean lake trout, Chinook salmon, and walleye, respectively. Siscowet lake trout lost 3 days per decade. Consequently, preferred habitat spatial extents increased at a rate of 579, 495 and 419 km(2) per year for the lean lake trout, Chinook salmon, and walleye while siscowet lost 161 km(2) per year during the modeled period. Habitat increases could lead to increased growth and production for three of the four fishes. Consequently, greater habitat overlap may intensify interguild competition and food web interactions. Loss of cold-water habitat for siscowet, having the coldest thermal preference, could forecast potential changes from continued warming. Additionally, continued warming may render more suitable conditions for some invasive species.

  12. Climate warming reduces fish production and benthic habitat in Lake Tanganyika, one of the most biodiverse freshwater ecosystems

    PubMed Central

    Gergurich, Elizabeth L.; Kraemer, Benjamin M.; McGlue, Michael M.; McIntyre, Peter B.; Russell, James M.; Simmons, Jack D.; Swarzenski, Peter W.

    2016-01-01

    Warming climates are rapidly transforming lake ecosystems worldwide, but the breadth of changes in tropical lakes is poorly documented. Sustainable management of freshwater fisheries and biodiversity requires accounting for historical and ongoing stressors such as climate change and harvest intensity. This is problematic in tropical Africa, where records of ecosystem change are limited and local populations rely heavily on lakes for nutrition. Here, using a ∼1,500-y paleoecological record, we show that declines in fishery species and endemic molluscs began well before commercial fishing in Lake Tanganyika, Africa’s deepest and oldest lake. Paleoclimate and instrumental records demonstrate sustained warming in this lake during the last ∼150 y, which affects biota by strengthening and shallowing stratification of the water column. Reductions in lake mixing have depressed algal production and shrunk the oxygenated benthic habitat by 38% in our study areas, yielding fish and mollusc declines. Late-20th century fish fossil abundances at two of three sites were lower than at any other time in the last millennium and fell in concert with reduced diatom abundance and warming water. A negative correlation between lake temperature and fish and mollusc fossils over the last ∼500 y indicates that climate warming and intensifying stratification have almost certainly reduced potential fishery production, helping to explain ongoing declines in fish catches. Long-term declines of both benthic and pelagic species underscore the urgency of strategic efforts to sustain Lake Tanganyika’s extraordinary biodiversity and ecosystem services. PMID:27503877

  13. Climate warming reduces fish production and benthic habitat in Lake Tanganyika, one of the most biodiverse freshwater ecosystems

    USGS Publications Warehouse

    Cohen, Andrew S.; Gergurich, Elizabeth L.; Kraemer, Benjamin M.; McGlue, Michael M.; McIntyre, Peter B.; Russell, James M.; Simmons, Jack D.; Swarzenski, Peter W.

    2016-01-01

    Warming climates are rapidly transforming lake ecosystems worldwide, but the breadth of changes in tropical lakes is poorly documented. Sustainable management of freshwater fisheries and biodiversity requires accounting for historical and ongoing stressors such as climate change and harvest intensity. This is problematic in tropical Africa, where records of ecosystem change are limited and local populations rely heavily on lakes for nutrition. Here, using a ∼1,500-y paleoecological record, we show that declines in fishery species and endemic molluscs began well before commercial fishing in Lake Tanganyika, Africa’s deepest and oldest lake. Paleoclimate and instrumental records demonstrate sustained warming in this lake during the last ∼150 y, which affects biota by strengthening and shallowing stratification of the water column. Reductions in lake mixing have depressed algal production and shrunk the oxygenated benthic habitat by 38% in our study areas, yielding fish and mollusc declines. Late-20th century fish fossil abundances at two of three sites were lower than at any other time in the last millennium and fell in concert with reduced diatom abundance and warming water. A negative correlation between lake temperature and fish and mollusc fossils over the last ∼500 y indicates that climate warming and intensifying stratification have almost certainly reduced potential fishery production, helping to explain ongoing declines in fish catches. Long-term declines of both benthic and pelagic species underscore the urgency of strategic efforts to sustain Lake Tanganyika’s extraordinary biodiversity and ecosystem services.

  14. Socio-Economics of Lake Victoria's Fisheries: An Analysis of the Shifting Roles and Status of Women Fish Traders

    ERIC Educational Resources Information Center

    Craig, Heather

    2007-01-01

    Fishing industries around the world are currently undergoing a process of industrialization and commercialization. A similar story is unfolding in many fishing communities: large-scale industrial fishers who possess enormous capital and advanced technologies are threatening the lives of small-scale fisherfolk. The fishing industry in Lake Victoria…

  15. Pleistocene desiccation in East Africa bottlenecked but did not extirpate the adaptive radiation of Lake Victoria haplochromine cichlid fishes.

    PubMed

    Elmer, Kathryn R; Reggio, Chiara; Wirth, Thierry; Verheyen, Erik; Salzburger, Walter; Meyer, Axel

    2009-08-11

    The Great Lakes region of East Africa, including Lake Victoria, is the center of diversity of the mega-diverse cichlid fishes (Perciformes: Teleostei). Paleolimnological evidence indicates dramatic desiccation of this lake ca. 18,000-15,000 years ago. Consequently, the hundreds of extant endemic haplochromine species in the lake must have either evolved since then or refugia must have existed, within that lake basin or elsewhere, from which Lake Victoria was recolonized. We studied the population history of the Lake Victoria region superflock (LVRS) of haplochromine cichlids based on nuclear genetic analysis (12 microsatellite loci from 400 haplochomines) of populations from Lake Kivu, Lake Victoria, and the connected and surrounding rivers and lakes. Population genetic analyses confirmed that Lake Kivu haplochromines colonized Lake Victoria. Coalescent analyses show a 30- to 50-fold decline in the haplochromine populations of Lake Victoria, Lake Kivu, and the region ca. 18,000-15,000 years ago. We suggest that this coincides with drastic climatic and geological changes in the late Pleistocene. The most recent common ancestor of the Lake Victoria region haplochromines was estimated to have existed about 4.5 million years ago, which corresponds to the first radiation of cichlids in Lake Tanganyika and the origin of the tribe Haplochrominii. This relatively old evolutionary origin may explain the high levels of polymorphism still found in modern haplochromines. This degree of polymorphism might have acted as a "genetic reservoir" that permitted the explosive radiation of hundreds of haplochromines and their array of contemporary adaptive morphologies.

  16. High levels, partitioning and fish consumption based water guidelines of perfluoroalkyl acids downstream of a former firefighting training facility in Canada.

    PubMed

    Bhavsar, Satyendra P; Fowler, Craig; Day, Sarah; Petro, Steve; Gandhi, Nilima; Gewurtz, Sarah B; Hao, Chunyan; Zhao, Xiaoming; Drouillard, Ken G; Morse, Dave

    2016-09-01

    High levels of perfluoroalkyl acids (PFAAs), especially perfluorooctane sulfonic acid (PFOS), have been observed at locations in/around/downstream of the sites where PFOS-based firefighting foam was used repeatedly for a prolonged period. In this study, we conducted a detailed investigation of PFAA contamination in the Lake Niapenco area in Ontario, Canada, where among the highest ever reported levels of PFOS were recently measured in amphipods, fish and snapping turtle plasma. Levels and distribution of PFAAs in water, sediment and fish samples collected from the area varied widely. An upstream pond beside a former firefighting training area (FFTA) was confirmed as the source of PFAAs even 20years after the last use of the foam at the FFTA. Recent PFOS concentration in water (~60ng/L) at Lake Niapenco, about 14km downstream of the pond, was still 3-7× higher than the background levels. For PFOS, Log KD ranged 1.3-2.5 (mean±SE: 1.7±0.1), Log BAFs ranged 2.4-4.7 (3.4±0.05), and Log BSAFs ranged 0.7-2.9 (1.7±0.05). Some fish species-specific differences in BAF and BSAF were observed. At Log BAF of 4.7, fish PFOS levels at Lake Niapenco could reach 15,000ng/g, 100× greater than a "do not eat" advisory benchmark, without exceeding the current drinking water guideline of 300ng/L. A fish consumption based water guideline was estimated at 1-15ng/L, which is likely applicable worldwide given that the Log BAFs observed in this study were comparable to those previously reported in the literature. It appears that PFAA in the downstream waters increased between 2011 and 2015; however, further monitoring is required to confirm this trend.

  17. Simulation of Fish, Mud, and Crystal Lakes and the shallow ground-water system, Dane County, Wisconsin

    USGS Publications Warehouse

    Krohelski, James T.; Lin, Yu-Feng; Rose, William J.; Hunt, Randall J.

    2002-01-01

    Model results suggest that the increase in regional ground-water recharge resulted in increased ground-water flow to the lake, which in turn resulted in increased lake stages. Simulation results of withdrawal of water from Fish Lake at 500 gallons per minute, assuming 1990?98 climatic conditions, indicate that after 1 year of pumping the stage of Fish and Mud Lakes would be reduced more than 1 foot and the stage of Crystal Lake would be reduced by less than 0.2 foot. When pumping is stopped, the lake stages would recover to near pre-pumping levels within about 3 years. When pumping is extended to 5 years, Fish and Mud Lake stage would be reduced by a maximum of 3.8 feet and Crystal Lake stage is reduced a maximum of 0.8 feet. After 4 years of recovery, Fish and Mud Lake stages are within 0.9 foot of prepumping levels and Crystal Lake stage is within 0.7 foot.

  18. Fish consumption and contaminant exposure among Montreal-area sportfishers: pilot study.

    PubMed

    Kosatsky, T; Przybysz, R; Shatenstein, B; Weber, J P; Armstrong, B

    1999-02-01

    A 1995 pilot study assessed sport fish consumption and contaminant exposure among Montreal-area residents fishing the frozen St. Lawrence River. Interviews conducted among 223 ice fishers met on-site were used to create an index of estimated exposure to fish-borne contaminants. A second-stage assessment of sport fish consumption and tissue contaminant burdens included 25 interviewees at the highest level of estimated contaminant exposure (of 38, or 66% of those solicited) and 15 low-exposure fishers (of 41, or 37% of those solicited). High-level fisher-consumers reported eating 0. 92+/-0.99 sport fish meals/week during the previous 3 weeks compared to 0.38+/-0.21 (P<0.05) for the low-level group. Based on the product of consumption frequency times mass of sport fish meals consumed, high-level consumers ate a mean of 18.3 kg of sport fish annually versus 3.3 kg for the low-level consumers. Tissue contaminant assessments showed significant (P<0.05) groupwise differences: 0-1 cm hair mercury (median 0.73 microgram/g for the high versus 0.23 microgram/g for the low group), lipid-adjusted plasma PCB congeners (Aroclor 1260: median 0.77 microgram/g versus 0.47 microgram/g), and lipid-adjusted plasma DDE (median 0.35 microgram/g versus 0.26 microgram/g). No participant had a hair mercury or plasma DDE concentration above Health Canada recommendations but 2/25 high-level participants (8%) had plasma Aroclor 1260 concentrations above recommended limits. The results of this pilot study suggest that a small number of Montreal-area sportfishers consume their catch as often as three times weekly and that those consuming sport fish frequently have significantly higher tissue levels of mercury, PCBs, and DDE than do infrequent consumers. On the other hand, compared to other groups in Quebec, such as the Inuit or commercial fishers on the North Shore of the Gulf of St. Lawrence, Montreal-area sportfishers eat less fish and have lower tissue concentrations of fish

  19. Developing fish trophic interaction indicators of climate change for the Great Lakes

    USGS Publications Warehouse

    Kraus, Richard T.; Knight, Carey T.; Gorman, Ann Marie; Kocovsky, Patrick M.; Weidel, Brian C.; Rogers, Mark W.

    2016-01-01

    This project addressed regional climate change effects on aquatic food webs in the Great Lakes. We sought insights by examining Lake Erie as a representative system with a high level of anthropogenic impacts, strong nutrient gradients, seasonal hypoxia, and spatial overlap of cold- and cool-water fish guilds. In Lake Erie and in large embayments throughout the Great Lakes basin, this situation is a concern for fishery managers, as climate change may exacerbate hypoxia and reduce habitat volume for some species. We examined fish community composition, fine-scale distribution, prey availability, diets, and biochemical tracers for dominant fishes from study areas with medium-high nutrient levels (mesotrophic, Fairport study area), and low nutrient levels (oligotrophic, Erie study area). This multi-year database (2011-2013) provides the ability to contrast years with wide variation in rainfall, winter ice-cover, and thermal stratification. In addition, multiple indicators of dietary and distributional responses to environmental variability will allow resource managers to select the most informative approach for addressing specific climate change questions. Our results support the incorporation of some relatively simple and cost-efficient approaches into existing agency monitoring programs to track the near-term condition status of fish and fish community composition by functional groupings. Other metrics appear better suited for understanding longer-term changes, and may take more resources to implement on an ongoing basis. Although we hypothesized that dietary overlap and similarity in selected species would be sharply different during thermal stratification and hypoxic episodes, we found little evidence of this. Instead, to our surprise, this study found that fish tended to aggregate at the edges of hypoxia, highlighting potential spatial changes in catch efficiency of the fishery. This work has had several positive impacts on a wide range of resource management and

  20. Rapid sympatric ecological differentiation of crater lake cichlid fishes within historic times

    PubMed Central

    2010-01-01

    Background After a volcano erupts, a lake may form in the cooled crater and become an isolated aquatic ecosystem. This makes fishes in crater lakes informative for understanding sympatric evolution and ecological diversification in barren environments. From a geological and limnological perspective, such research offers insight about the process of crater lake ecosystem establishment and speciation. In the present study we use genetic and coalescence approaches to infer the colonization history of Midas cichlid fishes (Amphilophus cf. citrinellus) that inhabit a very young crater lake in Nicaragua-the ca. 1800 year-old Lake Apoyeque. This lake holds two sympatric, endemic morphs of Midas cichlid: one with large, hypertrophied lips (~20% of the total population) and another with thin lips. Here we test the associated ecological, morphological and genetic diversification of these two morphs and their potential to represent incipient speciation. Results Gene coalescence analyses [11 microsatellite loci and mitochondrial DNA (mtDNA) sequences] suggest that crater lake Apoyeque was colonized in a single event from the large neighbouring great lake Managua only about 100 years ago. This founding in historic times is also reflected in the extremely low nuclear and mitochondrial genetic diversity in Apoyeque. We found that sympatric adult thin- and thick-lipped fishes occupy distinct ecological trophic niches. Diet, body shape, head width, pharyngeal jaw size and shape and stable isotope values all differ significantly between the two lip-morphs. The eco-morphological features pharyngeal jaw shape, body shape, stomach contents and stable isotopes (δ15N) all show a bimodal distribution of traits, which is compatible with the expectations of an initial stage of ecological speciation under disruptive selection. Genetic differentiation between the thin- and thick-lipped population is weak at mtDNA sequence (FST = 0.018) and absent at nuclear microsatellite loci (FST < 0

  1. L-Lake fish: L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1991

    SciTech Connect

    Sayers, R.E. Jr.; Mealing, H.G. III

    1992-04-01

    The L Lake Biological Monitoring Program was designed to meet environmental regulatory requirements associated with the re-start of L-Reactor and address portions of Section 316(a) of the Clean Water Act, which requires an applicant for a discharge permit to provide scientific evidence that the discharge causes no significant impact on the indigenous ecosystem. The Department of Energy (DOE) must demonstrate that the discharge of L-Reactor effluent into L Lake will not inhibit the eventual establishment of a ``Balanced Biological Community`` (BBC) in at least 50% of the lake.

  2. CREATION OF A GEOGRAPHIC INFORMATION SYSTEM TO IDENTIFY AT-RISK POPULATIONS IN NEW JERSEY AND NEW YORK FOR CONSUMPTION OF CONTAMINATED FISH AND SEAFOOD

    EPA Science Inventory

    Project Objective: To identify at-risk populations, particularly women of child bearing years and young children, for consumption of contaminated fish and seafood via the use of geographically and demographically defined seafood consumption patterns and fish/seafood contaminatio...

  3. Visual Sensitivity of Deepwater Fishes in Lake Superior

    PubMed Central

    Harrington, Kelly A.; Hrabik, Thomas R.; Mensinger, Allen F.

    2015-01-01

    The predator-prey interactions in the offshore food web of Lake Superior have been well documented, but the sensory systems mediating these interactions remain unknown. The deepwater sculpin, (Myoxocephalus thompsoni), siscowet (Salvelinus namaycush siscowet), and kiyi (Coregonus kiyi) inhabit low light level environments. To investigate the potential role of vision in predator-prey interactions, electroretinography was used to determine visual sensitivity for each species. Spectral sensitivity curves revealed peak sensitivity at 525 nm for each species which closely corresponds to the prevalent downwelling light spectrum at depth. To determine if sufficient light was available to mediate predator-prey interactions, visual sensitivity was correlated with the intensity of downwelling light in Lake Superior to construct visual depth profiles for each species. Sufficient daytime irradiance exists for visual interactions to approximately 325 m for siscowet and kiyi and 355 m for the deepwater sculpin during summer months. Under full moon conditions, sufficient irradiance exists to elicit ERG response to light available at approximately 30 m for the siscowet and kiyi and 45 m for the deepwater sculpin. Visual interactions are therefore possible at the depths and times when these organisms overlap in the water column indicating that vision may play a far greater role at depth in deep freshwater lakes than had been previously documented. PMID:25646781

  4. Persistent Organic Pollutants and Biomarkers of Diabetes Risk in a Cohort of Great Lakes Sport Caught Fish Consumers

    PubMed Central

    Turyk, Mary; Fantuzzi, Giamila; Persky, Victoria; Freels, Sally; Lambertino, Anissa; Pini, Maria; Rhodes, Davina H.; Anderson, Henry A.

    2015-01-01

    Background Exposure to persistent organic pollutants (POPs) is associated with increased diabetes risk, although the mechanism of action is not well delineated. Methods We investigated established diabetes biomarkers that could implicate potential mechanistic pathways, including C-reactive protein (CRP), a marker of systemic inflammation; gamma glutamyl transferase (GGT), a liver enzyme associated with oxidative stress; and adiponectin, an adipokine modulating glucose regulation and fatty acid oxidation. These biomarkers as well as hemoglobin A1c (HA1c), and POPs [polychlorinated biphenyls (PCBs), p,p-dichlorodiphenyldichloroethylene (DDE) and polybrominated diphenyl ethers (PBDEs)] were measured in a cohort of Great Lakes sport caught fish (GLSCF) consumers. We examined associations of POPs and fish consumption with HA1c and incident diabetes, and evaluated mediation and moderation by diabetes biomarkers. Results Odds of incident diabetes were elevated with exposure to DDE and PCBs. DDE and PCB 118 were positively, and fish meals were inversely, associated with HA1c. CRP was inversely associated with saltwater and total fish meals, particularly in persons with higher adiposity, but did not mediate the associations of fish meals with HA1c. There were few associations of adiponectin, CRP and GGT with POPs, with the exception of positive associations of GGT with PCB 118 and with PBDEs in older persons, and a positive association of adiponectin with PBDEs. Adiponectin, CRP and GGT did not mediate associations of DDE and PCBs with HA1c or incident diabetes. However, the association of DDE with HA1c was stronger in persons with higher CRP, GGT and BMI, and lower adiponectin, while the association of PCB 118 with HA1c was stronger in persons with higher GGT. Conclusions These findings suggest that adiponectin, CRP and GGT did not mediate effects of POPs on diabetes or HA1c. However, POPs may have stronger effects on blood glucose in persons at higher risk for diabetes

  5. Fishing, fish consumption, and awareness about warnings in a university community in central New Jersey in 2007, and comparisons with 2004.

    PubMed

    Burger, Joanna

    2008-09-01

    Fish are a healthy source of protein, but the risks from consuming fish have become a national concern. Over the past 7 years, there have been a number of national advisories regarding saltwater fish. Fish consumption patterns and public knowledge about advisories and warnings have been examined for at-risk populations, but there is little information about the latter for a general population, or of temporal trends in such information acquisition. Information about the benefits and health risks of consuming fish, health warnings from the New Jersey Department of Environmental Protection and the Food and Drug Administration, belief in these warnings, and trust in different sources of information were examined in a sample of 460 people within a university community in central New Jersey in 2007. The null hypothesis of no differences in fishing, consumption, and knowledge about advisories as a function of age, gender, ethnicity, and education was tested. In 2007, only 30% of the study population fished, and 83% of the study population ate fish, either commercial or self-caught. There were differences in fishing behavior, consumption patterns, and awareness of advisories as a function of gender, ethnicity, age, and education. Most notably, nearly twice as many men as women fished, Whites fished more and Blacks and Indian/Pakistanis fished less than other ethnic groups, and people aged 23-35 fished more than did others. About 8% of fish meals were from self-caught fish, 32% were eaten in restaurants, and 60% were of fish bought in stores and cooked at home. Men ate more meals of self-caught fish than did females, and Asians ate more meals of fish in restaurants, and Blacks ate more meals of store-bought fish than other ethnic groups. The total number of fish meals consumed per month increased significantly with age. Overall, more people had heard about the benefits (92%) than the risks (78%) of fish consumption. When asked whom they trust for information about health

  6. Occurrence of pesticides in fish tissues, water and soil sediment from Manzala Lake and River Nile.

    PubMed

    Osfor, M M; Abd el Wahab, A M; el Dessouki, S A

    1998-02-01

    Pesticides constitute the major source of potential environmental hazard to man and animal as they are present and concentrated in the food chain. This study was conducted on 136 samples of water, sediment and fish for detection and determination of pesticide residues in this ecosystem. Highly significant differences were found in levels of Indian, heptachlor, endrin, dieldrin, P,P'-DDE and propoxur in River Nile water when compared with that of Manzala Lake. Levels of Indian, endrin, malathion and diazinon were significantly higher in soil sediment of Manzala Lake, while the levels of heptachlor, aldrine, P,P'-DDE, DDT, parathion, propoxur and zectran were significantly higher in soil sediment of River Nile. Boury fish of Manzala Lake contained higher levels of heptachlor, aldrin, P,P'-DDE and malathion, while boury fish of River Nile contained a higher level of zectran only. This survey, thus indicated that Manzala Lake and even the River Nile which was used as control are heavily contaminated with chlorinated hydrocarbons (Indian, heptachlor, aldrin, endrin, dieldrin, P,P'-DDE and DDT), organic phosphorus compounds (malathion, dimethoat, diazinon and parathion) and carbamate pesticides (propoxur and zectran).

  7. Reproduction and distribution of fishes in a cooling lake: Wisconsin power plant impact study

    SciTech Connect

    Rondorf, D.W.; Kitchell, J.F.

    1985-06-01

    Spatial and temporal patterns during reproduction and early-life history of fishes were studied in a manmade cooling lake. Lake Columbia, impounded in 1974, near Portage, Wisconsin, has an area of 190 ha, a mean depth of 2.1 m, and a 15C temperature gradient derived from the thermal effluent of a 527-MW fossil-fueled generating station that began operating in 1975. The lake was initially colonized by fishes when filled with Wisconsin River water. Observations suggest a decline of species diversity of the fish community due to direct action of upper lethal temperatures, absence of colonization by warm-water, lake-dwelling species, and lack of recruitment for certain species. Spatial and temporal patterns of spawning of black crappie were altered by a rapid rise in water temperatures following plant startup after a three-week shutdown. Elevated temperatures subsequently shortened the spawning season, induced resorption of ova, and caused loss of secondary sexual characteristics. After initially drifting with water current, juvenile stages of sunfish and gizzard shad responded to changes in the thermal gradient by horizontal and vertical shifts in abundance.

  8. Fish, a Mediterranean source of n-3 PUFA: benefits do not justify limiting consumption.

    PubMed

    Gil, Angel; Gil, Fernando

    2015-04-01

    Fish is an important source of energy, high-quality proteins, fat, vitamins and minerals. Within lipids, n-3 long-chain PUFA (n-3 LC PUFA), mainly EPA and DHA, play an important role in health promotion and disease prevention. In contrast to the potential health benefits of dietary fish intake, certain chemical pollutants, namely heavy metals and some organic compounds, contained in seafood have emerged as an issue of concern, particularly for frequent fish consumers and sensitive groups of populations. The present review summarises the health benefits and risks of fish consumption. n-3 LC-PUFA are key compounds of cell membranes and play an important role in human health from conception through every stage of human development, maturation and ageing. DHA has a major role in the development of brain and retina during fetal development and the first 2 years of life and positively influences neurodevelopment, mainly visual acuity and cognitive functions. n-3 LC-PUFA are also effective in preventing cardiovascular events (mainly stroke and acute myocardial infarction) especially in persons with high cardiovascular risk. By contrast, there is convincing evidence of adverse neurological/neurodevelopmental outcomes in infants and young children associated with methylmercury exposure during fetal development due to maternal fish consumption during pregnancy. Dioxins and polychlorinated biphenyls present in contaminated fish may also develop a risk for both infants and adults. However, for major health outcomes among adults, the vast majority of epidemiological studies have proven that the benefits of fish intake exceed the potential risks with the exception of a few selected species in sensitive populations.

  9. Predictability of littoral-zone fish communities through ontogeny in Lake Texoma, Oklahoma-Texas, USA

    USGS Publications Warehouse

    Eggleton, M.A.; Ramirez, R.; Hargrave, C.W.; Gido, K.B.; Masoner, J.R.; Schnell, G.D.; Matthews, W.J.

    2005-01-01

    We sampled larval, juvenile and adult fishes from littoral-zone areas of a large reservoir (Lake Texoma, Oklahoma-Texas) (1) to characterize environmental factors that influenced fish community structure, (2) to examine how consistent fish-environment relationships were through ontogeny (i.e., larval vs. juvenile and adult), and (3) to measure the concordance of larval communities sampled during spring to juvenile and adult communities sampled at the same sites later in the year. Larval, juvenile and adult fish communities were dominated by Atherinidae (mainly inland silverside, Menidia beryllina) and Moronidae (mainly juvenile striped bass, Morone saxatilis) and were consistently structured along a gradient of site exposure to prevailing winds and waves. Larval, juvenile and adult communities along this gradient varied from atherinids and moronids at highly exposed sites to mostly centrarchids (primarily Lepomis and Micropterus spp.) at protected sites. Secondarily, zooplankton densities, water clarity, and land-use characteristics were related to fish community structure. Rank correlation analyses and Mantel tests indicated that the spatial consistency and predictability of fish communities was high as larval fishes sampled during spring were concordant with juvenile and adult fishes sampled at the same sites during summer and fall in terms of abundance, richness, and community structure. We propose that the high predictability and spatial consistency of littoral-zone fishes in Lake Texoma was a function of relatively simple communities (dominated by 1-2 species) that were structured by factors, such as site exposure to winds and waves, that varied little through time. ?? Springer 2005.

  10. Radionuclide concentrations in fish collected from Jemez, Nambe, and San Ildefonso Tribal Lakes

    SciTech Connect

    Fresquez, P.R.; Armstrong, D.R.; Salazar, J.G.

    1995-02-01

    Radionuclide concentrations ({sup 90}Sr, {sup 137}Cs, {sup 238}Pu, {sup 239}Pu,and total uranium) were determined in fish collected from Jemez, Nambe, and San Ildefonso tribal lakes. With the exception of {sup 137}Cs, all other radionuclides were not significantly different in (stocked) rainbow trout collected from Jemez and Nambe as compared with game fish collected from Abiquiu, Heron, and El Vado Reservoirs. Although {sup 137}Cs levels in trout from Jemez (3.2 {times} 10{sup -2} pCi per dry gram) and Nambe (7.5 {times} 10{sup -2} pCi per dry gram) were significantly higher than {sup 137}Cs concentrations in fish from Abiquiu, Heron, and El Vado, they were still well below the regional statistical (worldwide fallout) reference level (i.e., < 28 {times} 10{sup -2} pCi per dry gram). Game and nongame fish collected from San Ildefonso contained higher and significantly higher concentrations of uranium, respectively, as compared with fish collected from Abiquiu, Heron, and El Vado. The higher uranium concentrations in fish from San Ildefonso as compared with fish from Abiquiu, Heron, and El Vado were attributed to the higher natural soil uranium contents in the area as compared with the geology of the area upstream of San Ildefonso. The effective (radiation) dose equivalent (EDE) from consuming 46 lb of game fish from Jemez, Nambe, and San Ildefonso lakes, after natural background has been subtracted, was 0.013 ({+-}0.002), 0.019 ({+-}0.012), and 0.017 ({+-}0.028) mrem/yr, respectively. Similarly, the EDE from consuming nongame fish from San Ildefonso was 0.0092 ({+-}0.0084) mrem/yr. The highest calculated dose, based on the mean + 2 standard deviation (95% confidence level), was 0.073 mrem/yr; this was <0.08% of the International Commission on Radiological Protection permissible dose limit for protecting members of the public.

  11. 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.

  12. Nearshore energy subsidies support Lake Michigan fishes and invertebrates following major changes in food web structure

    USGS Publications Warehouse

    Turschak, Benjamin A; Bunnell, David B.; Czesny, Sergiusz J.; Höök, Tomas O.; Janssen, John; Warner, David M.; Bootsma, Harvey A

    2014-01-01

    Aquatic food webs that incorporate multiple energy channels (e.g. nearshore benthic or pelagic) with varying productivity and turnover rates convey stability to biological communities by providing multiple independent energy sources. Within the Lake Michigan food web, invasive dreissenid mussels have caused rapid changes to food web structure and potentially altered the channels through which consumers acquire energy. We used stable C and N isotopes to determine how Lake Michigan food web structure has changed in the past decade, coincident with the expansion of dreissenid mussels, decreased pelagic phytoplankton production and increased nearshore benthic algal production. Fish and invertebrate samples collected from sites around Lake Michigan were analyzed to determine taxa-specific 13C:12C (delta 13C) and 15N:14N (delta 15N) ratios. Sampling took place during two distinct periods, 2002-2003 and 2010-2012, that spanned the period of dreissenid expansion, and included nearshore, pelagic and profundal fish and invertebrate taxa. Magnitude and direction of the 13C shift indicated significantly greater reliance upon nearshore benthic energy sources among nearly all fish taxa as well as profundal invertebrates. Although the mechanisms underlying this 13C shift likely varied among species, possible causes include the transport of benthic algal production to offshore waters and an increased reliance on nearshore prey items. Delta 15N shifts were more variable and of smaller magnitude across taxa although declines in delta 15N among some pelagic fishes may indicate a shift to alternative prey resources. Lake Michigan fishes and invertebrates appear to have responded to dreissenid induced changes in nutrient and energy pathways by switching from pelagic to alternative nearshore energy subsidies. Although large shifts in energy allocation (i.e. pelagic to nearshore benthic) resulting from invasive species appear to have affected total production at upper trophic

  13. Nearshore energy subsidies support Lake Michigan fishes and invertebrates following major changes in food web structure.

    PubMed

    Turschak, Benjamin A; Bunnell, David; Czesny, Sergiusz; Höök, Tomas O; Janssen, John; Warner, David; Bootsma, Harvey A

    2014-05-01

    Aquatic food webs that incorporate multiple energy channels (e.g., nearshore benthic and pelagic) with varying productivity and turnover rates convey stability to biological communities by providing independent energy sources. Within the Lake Michigan food web, invasive dreissenid mussels have caused rapid changes to food web structure and potentially altered the channels through which consumers acquire energy. We used stable C and N isotopes to determine how Lake Michigan food web structure has changed in the past decade, coincident with the expansion of dreissenid mussels, decreased pelagic phytoplankton production, and increased nearshore benthic algal production. Fish and invertebrate samples collected from sites around Lake Michigan were analyzed to determine taxa-specific 13C:12C (delta13C) and 15N:14N (delta15N) ratios. Sampling took place during two distinct periods, 2002-2003 and 2010-2012, that spanned the period of dreissenid expansion, and included nearshore, pelagic and profundal fish and invertebrate taxa. The magnitude and direction of the delta13C shift indicated significantly greater reliance upon nearshore benthic energy sources among nearly all fish taxa as well as profundal invertebrates following dreissenid expansion. Although the mechanisms underlying this delta13C shift likely varied among species, possible causes include the transport of benthic algal production to offshore waters and increased feeding on nearshore prey items by pelagic and profundal species. delta15N shifts were more variable and of smaller magnitude across taxa, although declines in delta15N among some pelagic fishes suggest a shift to alternative prey resources. Lake Michigan fishes and invertebrates appear to have responded to dreissenid-induced changes in nutrient and energy pathways by switching from pelagic to alternative nearshore energy subsidies. Although large shifts in energy allocation (i.e., pelagic to nearshore benthic) resulting from invasive species appear

  14. Communicating methylmercury risks and fish consumption benefits to vulnerable childbearing populations.

    PubMed

    Kuntz, Sandra W; Ricco, Jason A; Hill, Wade G; Anderko, Laura

    2010-01-01

    Methylmercury is a known neurotoxin especially harmful to the fetus, infant, and child. Preventing exposure to this environmental toxin is best accomplished through consumer messages specifically adapted for local populations. Health care providers play an important role in the dissemination of information. The purpose of this article is to review the benefits and risks of fish consumption and identify strategies for presenting effective risk communication messages to vulnerable groups, particularly women of childbearing age.

  15. [Ectoparasite infection of some fish species in lake Pleshcheev].

    PubMed

    Zharikova, T I; Stepanova, M A; Zhokhov, A E

    2002-01-01

    Ectoparasites have been investigated on gills of the ruff, perch, white bream, roach, bream, ide, and European cisco from the Pleshcheevo lake. 13 parasite species were found: Dactylogyrus falcatus, D. distinguendus, D. cornoides, D. cornu, D. sphyrna, D. robustus, D. amphibothrium, Ancyrocephalus paradoxus, Argulus foliaceus, Ergasilus sieboldi, Achtheres percarum, Ancyrocephalus percae, and Rhipidocotyle companula. A reliable negative correlation between the number of monogeneans An. paradoxus and the copepods Ac. percarum on the perch. D. falcatus, the specific monogenean of the bream, was found on the roach. The comparison of the obtained data with those of 1939 has shown the decrease of oxyphilic copepods E. seiboldi, that prove the increasing eutrophication.

  16. High prevalence of non-synonymous substitutions in mtDNA of cichlid fishes from Lake Victoria.

    PubMed

    Shirai, Kazumasa; Inomata, Nobuyuki; Mizoiri, Shinji; Aibara, Mitsuto; Terai, Yohey; Okada, Norihiro; Tachida, Hidenori

    2014-12-01

    When a population size is reduced, genetic drift may fix slightly deleterious mutations, and an increase in nonsynonymous substitution is expected. It has been suggested that past aridity has seriously affected and decreased the populations of cichlid fishes in Lake Victoria, while geographical studies have shown that the water levels in Lake Tanganyika and Lake Malawi have remained fairly constant. The comparably stable environments in the latter two lakes might have kept the populations of cichlid fishes large enough to remove slightly deleterious mutations. The difference in the stability of cichlid fish population sizes between Lake Victoria and the Lakes Tanganyika and Malawi is expected to have caused differences in the nonsynonymous/synonymous ratio, ω (=dN/dS), of the evolutionary rate. Here, we estimated ω and compared it between the cichlids of the three lakes for 13 mitochondrial protein-coding genes using maximum likelihood methods. We found that the lineages of the cichlids in Lake Victoria had a significantly higher ω for several mitochondrial loci. Moreover, positive selection was indicated for several codons in the mtDNA of the Lake Victoria cichlid lineage. Our results indicate that both adaptive and slightly deleterious molecular evolution has taken place in the Lake Victoria cichlids' mtDNA genes, whose nonsynonymous sites are generally conserved.

  17. (90)Sr in fish from the southern Baltic Sea, coastal lagoons and freshwater lake.

    PubMed

    Zalewska, Tamara; Saniewski, Michał; Suplińska, Maria; Rubel, Barbara

    2016-07-01

    Activity concentrations of radioactive (90)Sr were studied in four fish species: herring, flounder, sprat and cod caught in the southern Baltic Sea in two periods: 2005-2009 and 2013-2014. The study included also perch from the coastal lagoons - Vistula Lagoon and Szczcin Lagoon and a freshwater lake - Żarnowieckie Lake as well as additional lake species: pike and bream. (90)Sr activity concentrations were compared in relation to species and to particular tissue: muscle, whole fish (eviscerated) and bones. In 2014, in the Baltic, the maximal (90)Sr concentrations were found in fishbones: herring - 0.39 Bq kg(-1) w.w., cod - 0.48 Bq kg(-1) w.w., and flounder - 0.54 Bq kg(-1) w.w. In the whole fish the maximal concentrations were found in flounder - 0.16 Bq kg(-1) w.w. and cod - 0.15 Bq kg(-1) w.w., while in herring - 0.022 Bq kg(-1) w.w. and sprat - 0.026 Bq kg(-1) w.w. they stayed at lower level. Relatively high (90)Sr concentrations were detected in whole fish from freshwater Lake Żarnowieckie: perch - 0.054 Bq kg(-1) w.w., pike - 0.062 Bq kg(-1) w.w. and bream - 0.140 Bq kg(-1) w.w. Concentration ratio (CR) determined for particular fish tissues and for whole eviscerated fish in relation to (90)Sr concentrations in seawater and lake water were showing significant variability unlike the corresponding (137)Cs concentration ratios which are stable and specific for fish species. The study corroborates with the conviction of the growing role of (90)Sr in the overall radioactivity in the southern Baltic Sea as compared to (137)Cs.

  18. Impacts of warm winters and extreme rainstorms on the base consumption in a limed lake, southern Norway.

    PubMed

    Andersen, Dag O

    2003-09-01

    The chemical composition of a limed lake, the two main inlets and the outlet was monitored during a period of 3 years. The winters of 1991-1992 and 1992-1993 were unusually warm while the winter of 1993-1994 was more normal. The lake surface water was wind exposed in the warm winters and as a consequence of frequent turnovers the acid input from the catchment mixed with the whole lake water body. In the winter of 1993-1994, the lake was ice-covered for approximately 4 months. During this period the drainage water from the catchment flowed to the outlet of the lake in the upper 2-3 m of the water column and only some of the acid input was neutralised. This is compared to a complete neutralisation in the winter of 1992-1993. The in-lake loss of alkalinity during this warm winter was approximately 29 microeq/l (November-June) compared to approximately 7 microeq/l lakewater in 1993-1994. Acid drainage from the catchment induced by an extraordinary rainstorm with heavy sea-salt deposition contributed to the in-lake alkalinity consumption in spring 1993. As winter temperatures above 0 degrees C and more frequent rainstorms may be common due to expected global warming, future increased lime consumption in-lakes may be projected in acidified areas as southern Norway.

  19. Fish oil consumption prevents glucose intolerance and hypercorticosteronemy in footshock-stressed rats

    PubMed Central

    2011-01-01

    Background Environmental stress plays an important role in the development of glucose intolerance influencing lipid and glucose metabolism through sympathetic nervous system, cytokines and hormones such as glucocorticoids, catecholamines and glucagon. Otherwise, fish oil prevents glucose intolerance and insulin resistance. Although the mechanisms involved are not fully understood, it is known that sympathetic and HPA responses are blunted and catecholamines and glucocorticoids concentrations can be modulated by fish consumption. The aim of the present study was to evaluate whether fish oil, on a normal lipidic diet: 1) could prevent the effect of footshock-stress on the development of glucose intolerance; 2) modified adiponectin receptor and serum concentration; and 3) also modified TNF-α, IL-6 and interleukin-10 (IL-10) levels in adipose tissue and liver. The study was performed in thirty day-old male Wistar randomly assigned into four groups: no stressed (C) and stressed (CS) rats fed with control diet, and no stressed (F) and stressed (FS) rats fed with a fish oil rich diet. The stress was performed as a three daily footshock stress sessions. Results Body weight, carcass fat and protein content were not different among groups. FS presented a reduction on the relative weight of RET. Basal serum glucose levels were higher in CS and FS but 15 min after glucose load just CS remained with higher levels than other groups. Serum corticosterone concentration was increased in CS, this effect was inhibited in FS. However, 15 min after footshock-stress, corticosterone levels were similar among groups. IL-6 was increased in EPI of CS but fish oil consumption prevented IL-6 increase in FS. Similar levels of TNF-α and IL-10 in RET, EPI, and liver were observed among groups. Adipo R1 protein concentration was not different among groups. Footshock-stress did not modify AdipoR2 concentration, but fish oil diet increases AdipoR2 protein concentration. Conclusions Footshock

  20. Fishing farmers or farming fishers? Fishing typology of inland small-scale fishing households and fisheries management in singkarak lake, west sumatra, indonesia.

    PubMed

    Yuerlita; Perret, Sylvain Roger; Shivakoti, Ganesh P

    2013-07-01

    Technical and socio-economic characteristics are known to determine different types of fishers and their livelihood strategies. Faced with declining fish and water resources, small-scale fisheries engage into transformations in livelihood and fishing practices. The paper is an attempt to understand these changes and their socio-economic patterns, in the case of Singkarak Lake in West Sumatra, Indonesia. Based upon the hypothesis that riparian communities have diverse, complex yet structured and dynamic livelihood systems, the paper's main objective is to study, document and model the actual diversity in livelihood, practices and performance of inland small-scale fisheries along the Singkarak Lake, to picture how households are adapted to the situation, and propose an updated, workable model (typology) of those for policy. Principal component analysis and cluster analysis were used to develop a typology of fishing households. The results show that small-scale fishers can be classified into different types characterized by distinct livelihood strategies. Three household types are identified, namely "farming fishers" households (type I, 30 %), "fishing farmers" households (type II, 30 %), and "mainly fishers" households (type III, 40 %). There are significant differences among these groups in the number of boats owned, annual fishing income, agriculture income and farming experience. Type I consists of farming fishers, well equipped, with high fishing costs and income, yet with the lowest return on fishing assets. They are also landowners with farming income, showing the lowest return on land capital. Type II includes poor fishing farmers, landowners with higher farming income; they show the highest return on land asset. They have less fishing equipment, costs and income. Type III (mainly fishers) consists of poorer, younger fishers, with highest return on fishing assets and on fishing costs. They have little land, low farming income, and diversified livelihood

  1. Fishing Farmers or Farming Fishers? Fishing Typology of Inland Small-Scale Fishing Households and Fisheries Management in Singkarak Lake, West Sumatra, Indonesia

    NASA Astrophysics Data System (ADS)

    Yuerlita; Perret, Sylvain Roger; Shivakoti, Ganesh P.

    2013-07-01

    Technical and socio-economic characteristics are known to determine different types of fishers and their livelihood strategies. Faced with declining fish and water resources, small-scale fisheries engage into transformations in livelihood and fishing practices. The paper is an attempt to understand these changes and their socio-economic patterns, in the case of Singkarak Lake in West Sumatra, Indonesia. Based upon the hypothesis that riparian communities have diverse, complex yet structured and dynamic livelihood systems, the paper's main objective is to study, document and model the actual diversity in livelihood, practices and performance of inland small-scale fisheries along the Singkarak Lake, to picture how households are adapted to the situation, and propose an updated, workable model (typology) of those for policy. Principal component analysis and cluster analysis were used to develop a typology of fishing households. The results show that small-scale fishers can be classified into different types characterized by distinct livelihood strategies. Three household types are identified, namely "farming fishers" households (type I, 30 %), "fishing farmers" households (type II, 30 %), and "mainly fishers" households (type III, 40 %). There are significant differences among these groups in the number of boats owned, annual fishing income, agriculture income and farming experience. Type I consists of farming fishers, well equipped, with high fishing costs and income, yet with the lowest return on fishing assets. They are also landowners with farming income, showing the lowest return on land capital. Type II includes poor fishing farmers, landowners with higher farming income; they show the highest return on land asset. They have less fishing equipment, costs and income. Type III (mainly fishers) consists of poorer, younger fishers, with highest return on fishing assets and on fishing costs. They have little land, low farming income, and diversified livelihood

  2. Relative importance of phosphorus, fish biomass, and watershed land use as drivers of phytoplankton abundance in shallow lakes.

    PubMed

    Gorman, Matt W; Zimmer, Kyle D; Herwig, Brian R; Hanson, Mark A; Wright, Robert G; Vaughn, Sean R; Younk, Jerry A

    2014-01-01

    Phytoplankton abundance in shallow lakes is potentially influenced by ambient phosphorus concentrations, nutrient loading accentuated by human activities in lake watersheds, and abundance of planktivorous and benthivorous fish. However, few studies have simultaneously assessed the relative importance of these factors influencing phytoplankton abundance over large spatial scales. We assessed relative influences of watershed characteristics, total phosphorus concentrations, and fish biomass on phytoplankton abundance in 70 shallow lakes in western Minnesota (USA) during summer 2005 and 2006. Our independent variables included total phosphorus (TP), benthivore biomass, planktivore biomass, summed planktivore and benthivore biomass (summed fish), areal extent of agriculture in the watershed, region (prairie versus parkland lakes), and year. Predictive models containing from one to three independent variables were compared using an information theoretic approach. The most parsimonious model consisted of TP and summed fish, and had over 10,000-fold greater support compared to models using just TP or summed fish, or models comprised of other variables. We also found no evidence that relative importance of predictor variables differed between regions or years, and parameter estimates of TP and summed fish were temporally and spatially consistent. TP and summed fish were only weakly correlated, and the model using both variables was a large improvement over using either variable alone. This indicates these two variables can independently increase phytoplankton abundance, which emphasizes the importance of managing both nutrients and fish when trying to control phytoplankton abundance in shallow lakes.

  3. Estimating Monthly Water Withdrawals, Return Flow, and Consumptive Use in the Great Lakes Basin

    USGS Publications Warehouse

    Shaffer, Kimberly H.; Stenback, Rosemary S.

    2010-01-01

    Water-resource managers and planners require water-withdrawal, return-flow, and consumptive-use data to understand how anthropogenic (human) water use affects the hydrologic system. Water models like MODFLOW and GSFLOW use calculations and input values (including water-withdrawal and return flow data) to simulate and predict the effects of water use on aquifer and stream conditions. Accurate assessments of consumptive use, interbasin transfer, and areas that are on public supply or sewer are essential in estimating the withdrawal and return-flow data needed for the models. As the applicability of a model to real situations depends on accurate input data, limited or poor water-use data hampers the ability of modelers to simulate and predict hydrologic conditions. Substantial differences exist among the many agencies nationwide that are responsible for compiling water-use data including what data are collected, how the data are organized, how often the data are collected, quality assurance, required level of accuracy, and when data are released to the public. This poster presents water-use information and estimation methods summarized from recent U.S. Geological Survey (USGS) reports with the intent to assist water-resource managers and planners who need estimates of monthly water withdrawals, return flows, and consumptive use. This poster lists references used in Shaffer (2009) for water withdrawals, consumptive use, and return flows. Monthly percent of annual withdrawals and monthly consumptive-use coefficients are used to compute monthly water withdrawals, consumptive use, and return flow for the Great Lakes Basin.

  4. Identification of Cryptosporidium Species in Fish from Lake Geneva (Lac Léman) in France.

    PubMed

    Certad, Gabriela; Dupouy-Camet, Jean; Gantois, Nausicaa; Hammouma-Ghelboun, Ourida; Pottier, Muriel; Guyot, Karine; Benamrouz, Sadia; Osman, Marwan; Delaire, Baptiste; Creusy, Colette; Viscogliosi, Eric; Dei-Cas, Eduardo; Aliouat-Denis, Cecile Marie; Follet, Jérôme

    2015-01-01

    Cryptosporidium, a protozoan parasite that can cause severe diarrhea in a wide range of vertebrates including humans, is increasingly recognized as a parasite of a diverse range of wildlife species. However, little data are available regarding the identification of Cryptosporidium species and genotypes in wild aquatic environments, and more particularly in edible freshwater fish. To evaluate the prevalence of Cryptosporidiumspp. in fish from Lake Geneva (Lac Léman) in France, 41 entire fish and 100 fillets (cuts of fish flesh) were collected from fishery suppliers around the lake. Nested PCR using degenerate primers followed by sequence analysis was used. Five fish species were identified as potential hosts of Cryptosporidium: Salvelinus alpinus, Esox lucius, Coregonus lavaretus, Perca fluviatilis, and Rutilus rutilus. The presence of Cryptosporidium spp. was found in 15 out of 41 fish (37%), distributed as follows: 13 (87%) C. parvum, 1 (7%) C. molnari, and 1 (7%) mixed infection (C. parvum and C. molnari). C. molnari was identified in the stomach, while C. parvum was found in the stomach and intestine. C. molnari was also detected in 1 out of 100 analyzed fillets. In order to identify Cryptosporidium subtypes, sequencing of the highly polymorphic 60-kDa glycoprotein (gp60) was performed. Among the C. parvum positive samples, three gp60 subtypes were identified: IIaA15G2R1, IIaA16G2R1, and IIaA17G2R1. Histological examination confirmed the presence of potential developmental stages of C. parvum within digestive epithelial cells. These observations suggest that C. parvum is infecting fish, rather than being passively carried. Since C. parvum is a zoonotic species, fish potentially contaminated by the same subtypes found in terrestrial mammals would be an additional source of infection for humans and animals, and may also contribute to the contamination of the environment with this parasite. Moreover, the risk of human transmission is strengthened by the

  5. Identification of Cryptosporidium Species in Fish from Lake Geneva (Lac Léman) in France

    PubMed Central

    Certad, Gabriela; Dupouy-Camet, Jean; Gantois, Nausicaa; Hammouma-Ghelboun, Ourida; Pottier, Muriel; Guyot, Karine; Benamrouz, Sadia; Osman, Marwan; Delaire, Baptiste; Creusy, Colette; Viscogliosi, Eric; Aliouat-Denis, Cecile Marie; Follet, Jérôme

    2015-01-01

    Cryptosporidium, a protozoan parasite that can cause severe diarrhea in a wide range of vertebrates including humans, is increasingly recognized as a parasite of a diverse range of wildlife species. However, little data are available regarding the identification of Cryptosporidium species and genotypes in wild aquatic environments, and more particularly in edible freshwater fish. To evaluate the prevalence of Cryptosporidiumspp. in fish from Lake Geneva (Lac Léman) in France, 41 entire fish and 100 fillets (cuts of fish flesh) were collected from fishery suppliers around the lake. Nested PCR using degenerate primers followed by sequence analysis was used. Five fish species were identified as potential hosts of Cryptosporidium: Salvelinus alpinus, Esox lucius, Coregonus lavaretus, Perca fluviatilis, and Rutilus rutilus. The presence of Cryptosporidium spp. was found in 15 out of 41 fish (37%), distributed as follows: 13 (87%) C. parvum, 1 (7%) C. molnari, and 1 (7%) mixed infection (C. parvum and C. molnari). C. molnari was identified in the stomach, while C. parvum was found in the stomach and intestine. C. molnari was also detected in 1 out of 100 analyzed fillets. In order to identify Cryptosporidium subtypes, sequencing of the highly polymorphic 60-kDa glycoprotein (gp60) was performed. Among the C. parvum positive samples, three gp60 subtypes were identified: IIaA15G2R1, IIaA16G2R1, and IIaA17G2R1. Histological examination confirmed the presence of potential developmental stages of C. parvum within digestive epithelial cells. These observations suggest that C. parvum is infecting fish, rather than being passively carried. Since C. parvum is a zoonotic species, fish potentially contaminated by the same subtypes found in terrestrial mammals would be an additional source of infection for humans and animals, and may also contribute to the contamination of the environment with this parasite. Moreover, the risk of human transmission is strengthened by the

  6. Recovery of a wild fish population from whole-lake additions of a synthetic estrogen.

    PubMed

    Blanchfield, Paul J; Kidd, Karen A; Docker, Margaret F; Palace, Vince P; Park, Brad J; Postma, Lianne D

    2015-03-03

    Despite widespread recognition that municipal wastewaters contain natural and synthetic estrogens, which interfere with development and reproduction of fishes in freshwaters worldwide, there are limited data on the extent to which natural populations of fish can recover from exposure to these compounds. We conducted whole-lake additions of an active component of the birth control pill (17α-ethynylestradiol; EE2) that resulted in the collapse of the fathead minnow (Pimephales promelas) population. Here we quantify physiological, population, and genetic characteristics of this population over the 7 years after EE2 additions stopped to determine if complete recovery was possible. By 3 years post-treatment, whole-body vitellogenin concentrations in male fathead minnow had returned to baseline, and testicular abnormalities were absent. In the spring of the fourth year, adult size-frequency distribution and abundance had returned to pretreatment levels. Microsatellite analyses clearly showed that postrecovery fish were descendants of the original EE2-treated population. Results from this whole-lake experiment demonstrate that fish can recover from EE2 exposure at the biochemical through population levels, although the timelines to do so are long for multigenerational exposures. These results suggest that wastewater treatment facilities that reduce discharges of estrogens and their mimics can improve the health of resident fish populations in their receiving environments.

  7. Levels of PCBs and trace metals in Crab Orchard Lake sediment, benthos, zooplankton, and fish

    SciTech Connect

    Kohler, C.C.; Heidinger, R.C.; Call, T.

    1990-02-01

    Concentrations of trace metals and PCBs in six species of fish, zooplankton, macrobenthos, sediment, and water were studied in Crab Orchard Lake, Williamson County, Illinois. Eleven sites were chosen throughout the lake, including one site (site 10) near an abandoned dumpsite of a former electrical transformer manufacturing facility. PCB levels in the selected components from site 10 were considerably higher than the other sites. Thirty-eight percent (17/45) of fish fillets from various species at this site exceeded the 2.00 mg/kg FDA guideline for PCBs. PCB concentrations in fish were variable, and little relationship existed between age or size and PCB concentrations in most species. Common carp and channel catfish had higher PCB levels than the other species examined. Trace metals were low in fish and other components analyzed and were comparable to literature values for the midwestern United States. Mercury was the only trace metal to exhibit a significant positive relationship with age or size of fish. Mercury was also the only trace metal to exhibit biomagnification.

  8. Aquatic Invertebrate Assemblages in Shallow Prairie Lakes: Fish and Environmental Influences

    USGS Publications Warehouse

    Paukert, C.P.; Willis, D.W.

    2003-01-01

    We sampled zooplankton and benthic macroinvertebrate assemblages in 30 shallow natural lakes to determine the effects of the environment (i.e., habitat and fish abundance) on invertebrates. Zooplankters were identified to genus, and up to 120 individuals per genus were measured. Macroinvertebrates were identified to order, class, or family. Fish communities were also sampled. Relative abundances of zooplankton and macroinvertebrates were low at increased chlorophyll a concentrations, although mean zooplankton length increased with total phosphorus, possibly because of an increased proportion of microzooplankton (rotifers and copepod nauplii) at higher phosphorus levels. Canonical correspondence analysis revealed that zooplankton and macroinvertebrate abundance was influenced by submersed vegetation coverage, whereas zooplankton abundance and size structure were also related to productivity (i.e., chlorophyll a and total phosphorus). However, relative abundance of fish species or fish feeding guilds was not strongly correlated with zooplankton or macroinvertebrate abundance or zooplankton size structure. Physical habitat (e.g., vegetation coverage) may exert substantial influences on invertebrate assemblages in these lakes, possibly providing a refuge from fish predation.

  9. A history of human impacts on the Lake Erie fish community

    USGS Publications Warehouse

    Reutter, Jeffrey M.; Hartman, Wilbur L.; Downhower, J.F.

    1988-01-01

    The fisheries scientist working in the island region of Lake Erie has access to an extremely large and diverse freshwater fish community. It is the intention of this essay to discuss briefly that community and the impacts of human activities to provide future students and researchers with both current and historical information. Human settlements and development within the basin are discussed, followed by a description of the major stresses on the community, the impacts of those stresses, and the resulting or present-day fish community.

  10. Metacercariae of Diplostomum spathaceum in the eyes of fishes from Yellowstone Lake, Wyoming.

    PubMed

    Dwyer, W P; Smith, C E

    1989-01-01

    Fish were collected from Yellowstone Lake, Wyoming (USA). Metacercariae of Diplostomum spathaceum was found in the lens of 11 of 12 longnose suckers (Catostomus catostomus). The mean number of metacercariae per sucker was 59 and the average age of the fish was 11.6 yr. There was no correlation between age and intensity of parasites (r = 0.24). Of 10 cutthroat trout (Salmo clarki) examined, there were metacercariae present in six. The metacercariae were found outside of the lens tissue in the trout; they occurred in the vitreous humor and the retina. These may be a different species from those found in the suckers.

  11. A shift in bloater consumption in Lake Michigan between 1993 and 2011 and its effects on Diporeia and Mysis prey

    USGS Publications Warehouse

    Pothoven, Steven A.; Bunnell, David B.

    2016-01-01

    Bioenergetics modeling was used to determine individual and population consumption by Bloater Coregonus hoyi in Lake Michigan during three time periods with variable Bloater density: 1993–1996 (high), 1998–2002 (intermediate), and 2009–2011 (low). Despite declines in Bloater abundance between 1993 and 2011, our results did not show any density-dependent compensatory response in annual individual consumption, specific consumption, or proportion of maximum consumption consumed. Diporeia spp. accounted for a steadily decreasing fraction of annual consumption, and Bloater were apparently unable to eat enough Mysis diluviana or other prey to account for the loss of Diporeia in the environment. The fraction of production of both Diporeia and Mysis that was consumed by the Bloater population decreased over time so that the consumption-to-production ratio for Diporeia + Mysis was 0.74, 0.26, and 0.14 in 1993–1996, 1998–2002, and 2009–2011, respectively. Although high Bloater numbers in the 1980s to 1990s may have had an influence on populations of Diporeia, Bloater were not the main factor driving Diporeia to a nearly complete disappearance because Diporeia continued to decline when Bloater predation demands were lessening. Thus, there appears to be a decoupling in the inverse relationship between predator and prey abundance in Lake Michigan. Compared with Alewife Alosa pseudoharengus, the other dominant planktivore in the lake, Bloater have a lower specific consumption and higher gross conversion efficiency (GCE), indicating that the lake can support a higher biomass of Bloater than Alewife. However, declines in Bloater GCE since the 1970s and the absence of positive responses in consumption variables following declines in abundance suggest that productivity in Lake Michigan might not be able to support the same biomass of Bloater as in the past.

  12. Teratogenic effects and monetary cost of selenium poisoning of fish in Lake Sutton, North Carolina.

    PubMed

    Lemly, A Dennis

    2014-06-01

    Selenium pollution from coal ash wastewater was investigated in Lake Sutton, NC. This lake has been continuously used as a cooling pond for a coal-fired power plant since 1972. Historic and recent levels of contamination in fish tissues (14-105µg Se/g dry weight in liver, 24-127 in eggs, 4-23 in muscle, 7-38 in whole-body) exceeded toxic thresholds and teratogenic effects were observed in fish collected in 2013. A high proportion (28.9 percent) of juvenile Lepomis spp. exhibited spinal and craniofacial malformations that were consistent with selenium poisoning. Teratogenic Deformity Index values indicated population-level impacts on the fishery. The partially monetized cost of resultant fishery losses was calculated at over $US 8.6 million annually, and over $US 217 million for the entire period of damage, which dates back to 1987 when chemical and biological monitoring began.

  13. Acute bioassays and hazard evaluation of representative contaminants detected in Great Lakes fish

    USGS Publications Warehouse

    Passino, Dora R. May; Smith, Stephen B.

    1987-01-01

    We have provided a hazard ranking for 19 classes of compounds representing many of the nearly 500 organic compounds identified by gas chromatography-mass spectrometry in lake trout (Salvelinus namaycush) and walleye (Stizostedion vitreum vitreum) from the Great Lakes and Lake St. Clair. We initially made a provisional hazard ranking based on available published and unpublished information on aquatic toxicity, bioaccumulation, occurrence and sources. Acute toxicity tests with Daphnia pulex at 17A°C in reconstituted hard water were performed with 30 compounds representative of the 19 classes that were highest in the provisional ranking. The resulting toxicity data, along with information on the compounds' occurrence in Great Lakes fish and their sources, were ranked and weighted and then used in calculating the revised hazard ranking. The 10 most hazardous classes, in descending order, are as follows (values shown are mean 48-h EC50s, in μ/ml): arene halides (e.g., polychlorinated biphenyls, DDT), 0.0011; phthalate esters, 0.133; chlorinated camphenes (toxaphene), 0.0082; polyaromatic hydrocarbons (PAHs; e.g., dimethylnaphthalene) and reduced derivatives, 1.01; chlorinated fused polycyclics (e.g., trans-nonachlor), 0.022; nitrogen-containing compounds (e.g., O-methylhydroxyl-amine), 1.35; alkyl halides (e.g., (bromomethyl)cyclohexene), 10.1; cyclic alkanes (e.g., cyclododecane), 20.9; silicon-containing compounds (e.g., dimethyldiethoxy silane), 1.25; and heterocyclic nitrogen compounds (e.g., nicotine), 2.48. We recommend that chronic bioassays be conducted with fish and invertebrates to determine the sublethal effects of the following classes of compounds, for which few toxicity data are available: PAHs, heterocyclic nitrogen compounds, other nitrogen-containing compounds, alkyl halides, cyclic alkanes and silicon-containing compounds. Information from these types of studies will aid researchers in determining the possible causal role these contaminants play in

  14. Fish Remains from Homestead Cave and Lake Levels of the Past 13,000 Years in the Bonneville Basin

    NASA Astrophysics Data System (ADS)

    Broughton, Jack M.; Madsen, David B.; Quade, Jay

    2000-05-01

    A late Quaternary ichthyofauna from Homestead Cave, Utah, provides a new source of information on lake history in the Bonneville basin. The fish, represented by 11 freshwater species, were accumulated between ˜11,200 and ˜1000 14C yr B.P. by scavenging owls. The 87Sr/ 86Sr ratio of Lake Bonneville varied with its elevation; 87Sr/ 86Sr values of fish from the lowest stratum of the cave suggest they grew in a lake near the terminal Pleistocene Gilbert shoreline. In the lowest deposits, a decrease in fish size and an increase in species tolerant of higher salinities or temperatures suggest multiple die-offs associated with declining lake levels. An initial, catastrophic, post-Provo die-off occurred at 11,300-11,200 14C yr B.P. and was followed by at least one rebound or recolonization of fish populations, but fish were gone from Lake Bonneville sometime before ˜10,400 14C yr B.P. This evidence is inconsistent with previous inferences of a near desiccation of Lake Bonneville between 13,000 and 12,000 14C yr B.P. Peaks in Gila atraria frequencies in the upper strata suggest the Great Salt Lake had highstands at ˜3400 and ˜1000 14C yr B.P.

  15. Use of fish-otolith-length regressions to infer size of double-crested cormorant prey fish from recovered otoliths in Lake Ontario

    USGS Publications Warehouse

    Ross, Robert M.; Johnson, James H.; Adams, Connie M.

    2005-01-01

    To provide a method for estimating fish size from fish otoliths for forensic applications or other predictive uses, morphometric measurements were obtained from three centrarchid fishes (pumpkinseed [Lepomis gibbosus], rock bass [Ambloplites rupestris], and smallmouth bass [Micropterus dolomieu]), two percids (yellow perch [Perca flavescens] and walleye [Stizostedion vitreum]), and one clupeid (alewife [Alosa pseudoharengus]) from the eastern basin of Lake Ontario. These species are the principal or economically important prey of Double-crested Cormorants (Phalacrocorax auritus), whose diet can be determined from regurgitated digestive pellets containing fish otoliths. A fuller understanding of the ecosystem roles of cormorants requires estimation of prey-fish size, obtainable from regressions of otolith length on fish length. Up to 100 fish of each species were collected from eastern Lake Ontario and measured for total length and otolith length. Least-squares regressions of otolith length on fish length were calculated for all species, covering life-stage ranges of immature fish to large adults near maximum known size. The regressions with 95% confidence intervals may be applicable outside the Lake Ontario ecosystem if used with caution.

  16. Analysis of remote sensing data for geothermal exploration over Fish Lake Valley, Esmeralda County, Nevada

    NASA Astrophysics Data System (ADS)

    Littlefield, Elizabeth F.

    The purpose of this study was to identify and map hydrothermal alteration and geothermal deposits in northern Fish Lake Valley, Nevada using both visible, near, shortwave infrared (0.4-2.5 microm) and thermal infrared (8-12 microm) remote sensing data. Visible, near, and shortwave infrared data were collected by four airborne instruments including NASA's Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and MODIS-ASTER (MASTER) instruments, HyVista Corporation's HyMap sensor, and SpecTIR Corporation's ProSpecTIR instrument. MASTER also collected thermal infrared data over Fish Lake Valley. Hydrothermal alteration minerals and hot spring deposits were identified using diagnostic spectra extracted from the remote sensing data. Mapping results were verified in the field using a portable spectrometer. Two areas of opaline sinter and travertine deposits were identified west of the Fish Lake Valley playa. Field observation reveals the alternating nature of these beds, which likely reflects fluctuating hot spring fluid chemistries. Sinter and travertine were likely deposited around fault-related hot springs during the Pleistocene when the water table was higher. Previously undiscovered Miocene crystalline travertine was identified within the Emigrant Hills near Columbus Salt Marsh. Argillic alteration was mapped in parts of the ranges surrounding Fish Lake Valley. Kaolinite, and to a lesser extent, muscovite and montmorillonite, were used as indicator minerals for argillic alteration. In these regions, thermal fluids were likely discharged from faults to alter rhyolite tuff. Mineral maps were synthesized with previously published geologic data and used to delineate four new targets for future geothermal exploration. The abundant hot spring deposits along the edge of the Volcanic Hills combined with argillic alteration minerals mapped in the ranges suggest geothermal influence throughout much of the valley.

  17. Polychlorinated biphenyls in sediments and fish species from the Murchison Bay of Lake Victoria, Uganda.

    PubMed

    Ssebugere, Patrick; Sillanpää, Mika; Wang, Pu; Li, Yingming; Kiremire, Bernard T; Kasozi, Gabriel N; Zhu, Chaofei; Ren, Daiwei; Zhu, Nali; Zhang, Haidong; Shang, Hongtao; Zhang, Qinghua; Jiang, Guibin

    2014-06-01

    Polychlorinated biphenyls (PCBs) were determined in sediments and two fish species collected from the Murchison Bay in Lake Victoria, using high resolution gas chromatography coupled to a high resolution mass spectrometer. Total PCB concentrations (Σ18PCBs) varied widely with mean values ranging from 777 to 4325pg g(-1) dry weight (dw) for sediments and 80 to 779pg g(-1) wet weight (ww) for fish. The PCB levels in the sediments were significantly higher at the station closest to Nakivubo channel, presumably due to effluents discharged by the channel, which may contain domestically produced commercial PCB mixtures. For fish, the concentrations in Nile perch (Lates niloticus) were significantly greater than those in Nile tilapia (Oreochromis niloticus) at all study stations, possibly due to dietary differences among species. World Health Organization-toxic equivalents (WHO2005-TEQs) for the dioxin-like PCBs were 0.04-0.64pg g(-1) dw and 0.01-0.39pg g(-1) ww for sediments and fish, respectively. The non-ortho PCBs exhibited the highest contribution to the Σ12TEQs (>75%) compared to the mono-ortho PCBs in both fish species. The TEQs in the present study were lower than many reported worldwide in literature for fish and were within the permissible level recommended by the European Commission, implying that the fish did not pose health hazards related to PCBs to the consumers.

  18. Temporal variation in fish mercury concentrations within lakes from the western Aleutian Archipelago, Alaska

    USGS Publications Warehouse

    Kenney, Leah A.; Eagles-Smith, Collin A.; Ackerman, Joshua T.; von Hippel, Frank A.

    2014-01-01

    We assessed temporal variation in mercury (Hg) concentrations of threespine stickleback (Gasterosteus aculeatus) from Agattu Island, Aleutian Archipelago, Alaska. Total Hg concentrations in whole-bodied stickleback were measured at two-week intervals from two sites in each of two lakes from June 1 to August 10, 2011 during the time period when lakes were ice-free. Across all sites and sampling events, stickleback Hg concentrations ranged from 0.37–1.07 µg/g dry weight (dw), with a mean (± SE) of 0.55±0.01 µg/g dw. Mean fish Hg concentrations declined by 9% during the study period, from 0.57±0.01 µg/g dw in early June to 0.52±0.01 µg/g dw in mid-August. Mean fish Hg concentrations were 6% higher in Loon Lake (0.56±0.01 µg/g dw) than in Lake 696 (0.53±0.01 µg/g dw), and 4% higher in males (0.56±0.01 µg/g dw) than in females (0.54±0.01 µg/g dw). Loon Lake was distinguished from Lake 696 by the presence of piscivorous waterbirds during the breeding season. Mercury concentrations in stickleback from Agattu Island were higher than would be expected for an area without known point sources of Hg pollution, and high enough to be of concern to the health of piscivorous wildlife.

  19. Temporal Variation in Fish Mercury Concentrations within Lakes from the Western Aleutian Archipelago, Alaska

    PubMed Central

    Kenney, Leah A.; Eagles-Smith, Collin A.; Ackerman, Joshua T.; von Hippel, Frank A.

    2014-01-01

    We assessed temporal variation in mercury (Hg) concentrations of threespine stickleback (Gasterosteus aculeatus) from Agattu Island, Aleutian Archipelago, Alaska. Total Hg concentrations in whole-bodied stickleback were measured at two-week intervals from two sites in each of two lakes from June 1 to August 10, 2011 during the time period when lakes were ice-free. Across all sites and sampling events, stickleback Hg concentrations ranged from 0.37–1.07 µg/g dry weight (dw), with a mean (± SE) of 0.55±0.01 µg/g dw. Mean fish Hg concentrations declined by 9% during the study period, from 0.57±0.01 µg/g dw in early June to 0.52±0.01 µg/g dw in mid-August. Mean fish Hg concentrations were 6% higher in Loon Lake (0.56±0.01 µg/g dw) than in Lake 696 (0.53±0.01 µg/g dw), and 4% higher in males (0.56±0.01 µg/g dw) than in females (0.54±0.01 µg/g dw). Loon Lake was distinguished from Lake 696 by the presence of piscivorous waterbirds during the breeding season. Mercury concentrations in stickleback from Agattu Island were higher than would be expected for an area without known point sources of Hg pollution, and high enough to be of concern to the health of piscivorous wildlife. PMID:25029042

  20. Estimating Consumption to Biomass Ratio in Non-Stationary Harvested Fish Populations

    PubMed Central

    Wiff, Rodrigo; Roa-Ureta, Ruben H.; Borchers, David L.; Milessi, Andrés C.; Barrientos, Mauricio A.

    2015-01-01

    The food consumption to biomass ratio (C) is one of the most important population parameters in ecosystem modelling because its quantifies the interactions between predator and prey. Existing models for estimating C in fish populations are per-recruit cohort models or empirical models, valid only for stationary populations. Moreover, empirical models lack theoretical support. Here we develop a theory and derive a general modelling framework to estimate C in fish populations, based on length frequency data and the generalised von Bertalanffy growth function, in which models for stationary populations with a sta