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Sample records for bird population trends

  1. Population trends from the North American Breeding Bird Survey

    USGS Publications Warehouse

    Peterjohn, B.G.; Sauer, J.R.; Robbins, C.S.

    1995-01-01

    INTRODUCTION: Most Neotropical migrant birds are difficult to count accurately and are moderately common over large breeding distributions. Consequently, little historical information exists on their large-scale population changes, and most of this information is anecdotal. Surveys begun in this century such as Breeding Bird Censuses and Christmas Bird Counts have the potential to provide this information, but only the North American Breeding Bird Survey (BBS) achieves the extensive continental coverage necessary to document population changes for most Neotropical migrant birds. Conservationists and ecologists have begun to use BBS data to estimate population trends, but there is still widespread confusion over exactly what these data show regarding population changes. In this chapter, we review the current state of knowledge regarding population changes in Neotropical migrant birds and the methods used to analyze these changes. The primary emphasis is on the BBS (Robbins et al. 1986) because this survey provides the best available data for estimating trends of Neotropical migrants on a continental scale. To address questions about methods of analyzing survey data, we review and compare some alternative methods of analyzing BBS data. We also discuss the effectiveness of the BBS in sampling Neotropical migrant species, and review possibilities for use of alternative data sets to verify trends from the BBS.

  2. Terrestrial bird population trends on Aguiguan (Goat Island), Mariana Islands

    USGS Publications Warehouse

    Amidon, Fred; Camp, Richard J.; Marshall, Ann P.; Pratt, Thane K.; Williams, Laura; Radley, Paul; Cruz, Justine B.

    2014-01-01

    The island of Aguiguan is part of the Mariana archipelago and currently supports populations of four endemic species, including one endemic genus, Cleptornis. Bird population trends since 1982 were recently assessed on the neighbouring islands of Saipan, Tinian, and Rota indicating declines in some native species. Point-transect surveys were conducted in 2008 by the U.S. Fish and Wildlife Service to assess population densities and trends on Aguiguan. Densities for six of the nine native birds—White-throated Ground-dove Gallicolumba xanthonura, Collared Kingfisher Todiramphus chloris, Rufous Fantail Rhipidura rufifrons, Golden White-eye Cleptornis marchei, Bridled White-eye Zosterops conspicillatus and Micronesian Starling Aplonis opaca—and the non-native bird—Island Collared-dove Streptopelia bitorquata—were significantly greater in 2008 than in 1982. No differences in densities were detected among the surveys for Mariana Fruit-dove Ptilinopus roseicapilla, and Micronesian MyzomelaMyzomela rubratra. Three federally and locally listed endangered birds—Nightingale Reed-warbler Acrocephalus luscinius, Mariana Swiftlet Collocalia bartschi, and Micronesian Megapode Megapodius laperous)—were either not detected during the point-transect counts, the surveys were not appropriate for the species, or the numbers of birds detected were too small to estimate densities. The factors behind the increasing trends for some species are unknown but may be related to increased forest cover on the island since 1982. With declining trends for some native species on neighbouring islands, the increasing and stable trends on Aguiguan is good news for forest bird populations in the region, as Aguiguan populations can help support conservation efforts on other islands in the archipelago.

  3. Population trends of woodland birds from the North American Breeding Bird Survey

    USGS Publications Warehouse

    Peterjohn, B.G.; Sauer, J.R.

    1994-01-01

    Population trends of woodland birds were summarized from BBS data over 1966-1991, 1966-1979, and 1982-1991. For the entire woodland bird assemblage, increasing species outnumbered decreasing species in all regions except central North America during 1966-1991. However, the proportion of decreasing species increased in most regions during the 19821991 interval. This population trend was most apparent for Neotropical migrants with 15 increasing and 2 decreasing species during 1966-1979 but only 4 increasing and 16 decreasing species during 1980-1991. Short-distance migrants and permanent residents had nearly equal numbers of increasing and decreasing species during both intervals.

  4. Double sampling to estimate density and population trends in birds

    USGS Publications Warehouse

    Bart, Jonathan; Earnst, Susan L.

    2002-01-01

    We present a method for estimating density of nesting birds based on double sampling. The approach involves surveying a large sample of plots using a rapid method such as uncorrected point counts, variable circular plot counts, or the recently suggested double-observer method. A subsample of those plots is also surveyed using intensive methods to determine actual density. The ratio of the mean count on those plots (using the rapid method) to the mean actual density (as determined by the intensive searches) is used to adjust results from the rapid method. The approach works well when results from the rapid method are highly correlated with actual density. We illustrate the method with three years of shorebird surveys from the tundra in northern Alaska. In the rapid method, surveyors covered ~10 ha h-1 and surveyed each plot a single time. The intensive surveys involved three thorough searches, required ~3 h ha-1, and took 20% of the study effort. Surveyors using the rapid method detected an average of 79% of birds present. That detection ratio was used to convert the index obtained in the rapid method into an essentially unbiased estimate of density. Trends estimated from several years of data would also be essentially unbiased. Other advantages of double sampling are that (1) the rapid method can be changed as new methods become available, (2) domains can be compared even if detection rates differ, (3) total population size can be estimated, and (4) valuable ancillary information (e.g. nest success) can be obtained on intensive plots with little additional effort. We suggest that double sampling be used to test the assumption that rapid methods, such as variable circular plot and double-observer methods, yield density estimates that are essentially unbiased. The feasibility of implementing double sampling in a range of habitats needs to be evaluated.

  5. American Exceptionalism: Population Trends and Flight Initiation Distances in Birds from Three Continents

    PubMed Central

    Møller, Anders Pape; Samia, Diogo S. M.; Weston, Mike A.; Guay, Patrick-Jean; Blumstein, Daniel T.

    2014-01-01

    Background All organisms may be affected by humans' increasing impact on Earth, but there are many potential drivers of population trends and the relative importance of each remains largely unknown. The causes of spatial patterns in population trends and their relationship with animal responses to human proximity are even less known. Methodology/Principal Finding We investigated the relationship between population trends of 193 species of bird in North America, Australia and Europe and flight initiation distance (FID); the distance at which birds take flight when approached by a human. While there is an expected negative relationship between population trend and FID in Australia and Europe, we found the inverse relationship for North American birds; thus FID cannot be used as a universal predictor of vulnerability of birds. However, the analysis of the joint explanatory ability of multiple drivers (farmland breeding habitat, pole-most breeding latitude, migratory habit, FID) effects on population status replicated previously reported strong effects of farmland breeding habitat (an effect apparently driven mostly by European birds), as well as strong effects of FID, body size, migratory habit and continent. Farmland birds are generally declining. Conclusions/Significance Flight initiation distance is related to population trends in a way that differs among continents opening new research possibilities concerning the causes of geographic differences in patterns of anti-predator behavior. PMID:25226165

  6. Bird population trends detected by the North American breeding bird survey

    USGS Publications Warehouse

    Bystrak, D.R.; Robbins, C.S.

    1977-01-01

    Continental populations of most bird species have remained quite stable since 1966, but there have been many regional changes associated with migration disasters, breeding failures and range expansions, and a few dramatic increases in populations of introduced species. These changes often are better represented by curvilinear than by linear regressions.

  7. Oak Ridge Reservation Bird Records and Population Trends

    SciTech Connect

    Roy, W. Kelly; Giffen, Neil R.; Wade, Murray; Haines, Angelina; Evans, James W.; Jett, Robert Trent

    2014-11-01

    Bird data have been collected through surveys, environmental assessments, and other observations for decades in the Oak Ridge National Environmental Research Park, located on the US Department of Energy s Oak Ridge Reservation (ORR) in East Tennessee. Birds were recorded in a variety of habitats, including wetlands, interior forests, grasslands, ponds, corridors, forest edges, and more. Most of the information was gathered from waterfowl surveys conducted from 1990 to 2008, from Partners in Flight (PIF) breeding bird surveys conducted from 1995 to 2013, and from past publications and research on Reservation birds. We have also included our own observations and, in a few instances, credible observations of ORR birds of which we have been made aware through eBird or discussions with area ornithologists and bird watchers. For the period 1950 2014, we were able to document 228 species of birds on the ORR. Several of these species are known from historic records only, while others were not known to have ever occurred on the Reservation until recently. This report does not include PIF breeding bird data from the 2014 season or any records after July 2014. Twenty-two species approximately 10% of the total number of species observed have state-listed status in Tennessee as endangered, threatened, or in need of management. Of the 228 species we documented, 120 are believed to be breeding birds on the ORR.

  8. Oak Ridge Reservation Bird Records and Population Trends

    SciTech Connect

    Roy, W. K.; Giffen, N. R.; Wade, M. C.; Haines, A. M.; Evans, J. W.; Jett, R. T.

    2014-09-01

    Bird data have been collected through surveys, environmental assessments, and other observations for decades in the Oak Ridge National Environmental Research Park, located on the US Department of Energy’s Oak Ridge Reservation (ORR) in East Tennessee. Birds were recorded in a variety of habitats, including wetlands, interior forests, grasslands, ponds, corridors, forest edges, and more. Most of the information was gathered from waterfowl surveys conducted from 1990 to 2008, from Partners in Flight (PIF) breeding bird surveys conducted from 1995 to 2013, and from past publications and research on Reservation birds. We have also included our own observations and, in a few instances, credible observations of ORR birds of which we have been made aware through eBird or discussions with area ornithologists and bird watchers. For the period 1950-2014, we were able to document 228 species of birds on the ORR. Several of these species are known from historic records only, while others were not known to have ever occurred on the Reservation until recently. This report does not include PIF breeding bird data from the 2014 season or any records after July 2014. Twenty-two species--approximately 10% of the total number of species observed--have state-listed status in Tennessee as endangered, threatened, or in need of management. Of the 228 species we documented, 120 are believed to be breeding birds on the ORR.

  9. Estimates of avian population trends from the North American Breeding Bird Survey

    USGS Publications Warehouse

    Geissler, P.H.; Noon, B.R.

    1981-01-01

    One of the major purposes of bird population studies is to document changes in population size over a period of years. The traditional method used in Europe and North America to detect population change is to calculate annual ratios. However, this method can produce spurious results when ratios are accumulated over many years. Consequently, new methods of computing trends are needed. Several new methods of estimating population trends are developed and illustrated with data from the North American Breeding Bird Survey (BBS). Each method is compared in terms of its assumptions, biases, and limitations. On the basis of these comparisons we recommend one method that we feel most accurately detects true population trends. Both the biological and statistical justifications for the model selection are presented. Trends estimated with this model are then presented for two species.

  10. Population trends of forest birds at Hakalau Forest National Wildlife Refuge, Hawai'i

    USGS Publications Warehouse

    Camp, Richard J.; Pratt, Thane K.; Gorresen, P. Marcos; Jeffrey, John J.; Woodworth, Bethany L.

    2010-01-01

    The Hakalau Forest National Wildlife Refuge was established to protect native Hawaiian forest birds, particularly endangered species. Management for forest restoration on the refuge has consisted mainly of removing feral ungulates, controlling invasive alien plants, and reforesting former pastures. To assess effects of this habitat improvement for forest birds, we estimated density annually by distance sampling and examined population trends for native and alien passerines over the 21 years since the refuge was established. We examined long-term trends and recent short-term trajectories in three study areas: (1) reforested pastureland, (2) heavily grazed open forest that was recovering, and (3) lightly grazed closed forest that was relatively intact. Three species of native birds and two species of alien birds had colonized the reforested pasture and were increasing. In the open forest, densities of all eight native species were either stable or increasing. Long-term trends for alien birds were also generally stable or increasing. Worryingly, however, during the most recent 9 years, in the open forest trajectories of native species were decreasing or inconclusive, but in the reforested pasture they generally increased. The closed forest was surveyed in only the most recent 9 years, and trajectories of native species there were mixed. Overall, long-term population trends in Hakalau are stable or increasing, contrasting with declines in most other areas of Hawai'i over the same period. However, more recent mixed results may indicate emergent problems for this important bird area.

  11. Population trends of North American sea ducks based on Christmas Bird Count and Breeding Bird Survey data

    USGS Publications Warehouse

    Niven, D.K.; Sauer, J.R.; Butcher, G.S.

    2005-01-01

    Due to the difficulty of conducting range-wide surveys of either breeding or wintering populations, few data are available to assess the population trends of sea ducks with confidence. We analyze sea duck data from the Audubon Christmas Bird Count (CBC) using hierarchical modeling methods that control for varying effort among circles and over time. These procedures allow us to assess early-winter relative density patterns among states and Bird Conservation Regions (BCRs) while also assessing trends in these regions and across the species North American range. Over the interval 1966-2003, continent-wide declines were observed in 1 of 11 species. Where sufficient data exist, we compare CBC results to estimates of population change derived from the USGS Breeding Bird Survey. The CBC does not effectively sample offshore populations of sea ducks; however, the CBC data can be used to assist in development of species-specific surveys, and CBC data can be used in combination with additional offshore sampling programs to better sample sea duck species.

  12. Population trends of black terns from the North American Breeding Bird Survey, 1966-1996

    USGS Publications Warehouse

    Peterjohn, B.G.; Sauer, J.R.

    1997-01-01

    Data from the North American Breeding Bird Survey indicate a survey-wide decline in Black Terns (Chlidonias niger) at an average rate of 3.1% annually during 1966-1996. Black Terns in Canada decreased at an average annual rate of 3.5% during this interval, while the United States population showed no significant trends. The long-term declines largely reflect trends prior to 1980, when the continental, Canadian, and United States populations decreased at average annual rates of 7.5%, 5.6%, and 11.9%, respectively. Most population trends were reversed during the 1990s, causing trend estimates over the 1980-1996 interval to become more positive. Associations between patterns of change in Black Terns, Mallards (Anas platyrhynchos), and numbers of ponds in the northern Great Plains suggest some relationships exist between habitat availability and the population trajectories.

  13. Population trends of Black Terns from the North American Breeding Bird Survey, 1966-1996

    USGS Publications Warehouse

    Peterjohn, B.G.; Sauer, J.R.

    1997-01-01

    Data from the North American Breeding Bird Survey indicate a survey-wide decline in Black Terns (Chlidonias niger) at an average rate of 3.1% annually during 1966-1996. Black Terns in Canada decreased at an average annual rate of 3.5% during this interval, while the United States population showed no significant trends. These long-term declines largely reflect trends prior to 1980, when the continental, Canadian, and United States populations decreased at average annual rates of 7.5%, 5.6%, and 11.9%, respectively. Most population trends were reversed during the 1990s, causing trend estimates over the 1980-1996 interval to become more positive. Associations between patterns of change in Black Terns, Mallards (Anas platyrhynchos), and numbers of ponds in the northern Great Plains suggest some relationships exist between habitat availability and the population trajectories.

  14. Mourning dove population trend estimates from Call-Count and North American Breeding Bird Surveys

    USGS Publications Warehouse

    Sauer, J.R.; Dolton, D.D.; Droege, S.

    1994-01-01

    The mourning dove (Zenaida macroura) Callcount Survey and the North American Breeding Bird Survey provide information on population trends of mourning doves throughout the continental United States. Because surveys are an integral part of the development of hunting regulations, a need exists to determine which survey provides precise information. We estimated population trends from 1966 to 1988 by state and dove management unit, and assessed the relative efficiency of each survey. Estimates of population trend differ (P lt 0.05) between surveys in 11 of 48 states; 9 of 11 states with divergent results occur in the Eastern Management Unit. Differences were probably a consequence of smaller sample sizes in the Callcount Survey. The Breeding Bird Survey generally provided trend estimates with smaller variances than did the Callcount Survey. Although the Callcount Survey probably provides more withinroute accuracy because of survey methods and timing, the Breeding Bird Survey has a larger sample size of survey routes and greater consistency of coverage in the Eastern Unit.

  15. Disentangling the relative importance of changes in climate and land-use intensity in driving recent bird population trends.

    PubMed

    Eglington, Sarah M; Pearce-Higgins, James W

    2012-01-01

    Threats to biodiversity resulting from habitat destruction and deterioration have been documented for many species, whilst climate change is regarded as increasingly impacting upon species' distribution and abundance. However, few studies have disentangled the relative importance of these two drivers in causing recent population declines. We quantify the relative importance of both processes by modelling annual variation in population growth of 18 farmland bird species in the UK as a function of measures of land-use intensity and weather. Modelled together, both had similar explanatory power in accounting for annual fluctuations in population growth. When these models were used to retrodict population trends for each species as a function of annual variation in land-use intensity and weather combined, and separately, retrodictions incorporating land-use intensity were more closely linked to observed population trends than retrodictions based only on weather, and closely matched the UK farmland bird index from 1970 onwards. Despite more stable land-use intensity in recent years, climate change (inferred from weather trends) has not overtaken land-use intensity as the dominant driver of bird populations. PMID:22479304

  16. An evaluation of marine bird population trends following the Exxon Valdez oil spill, Prince William Sound, Alaska.

    PubMed

    Lance, B K; Irons, D B; Kendall, S J; McDonald, L L

    2001-04-01

    We examined post-spill trends (1989-1998) of marine bird populations in Prince William Sound (PWS) following the Exxon Valdez oil spill (EVOS) to evaluate recovery of injured taxa. Two criteria were employed. First, we examined population trends of injured taxa only in the oiled area of PWS using regression models. Second, we examined population trends of injured taxa in the oiled area relative to the unoiled area using homogeneity of the slopes tests. We considered a population recovering if there was a positive trend using either criteria. We considered a population not recovering if there was no trend using either criteria or a negative trend in the oiled area. A significant negative trend in the oiled area relative to the unoiled area was considered a continuing and increasing effect. Most taxa for which injury was previously demonstrated were not recovering and some taxa showed evidence of increasing effects nine years after the oil spill. Four taxa (loons Gavia spp, Harlequin Duck Histrionicus histrionicus, Bufflehead Bucephala spp, and North-western Crow Corvus caurinus) showed weak to very weak evidence of recovery. None of these taxa showed positive trends in both winter and summer. Nine taxa (grebes Podiceps spp, cormorants Phalacrocorax spp, Black Oystercatcher Haematopus bachmani, Mew Gull Larus canus, Glaucous-winged Gull Larus glaucescens, terns Sterna spp, murres Uria spp, Pigeon Guillemot Cepphus columba, and murrelets Brachyramphus spp) showed no evidence of recovery during summer or winter. Four taxa (scoters Melanitta spp, mergansers Mergus spp, goldeneyes Bucephala spp, and Black-legged Kittiwaka Rissa tridactyla) showed evidence of continuing, increasing effects. We showed evidence of slow recovery, lack of recovery, and divergent population trends in many taxa which utilize shoreline and nearshore habitats where oil is likely to persist. Potential lingering spill effects and natural variability appear to be acting in concert in delaying

  17. Population Trends of Central European Montane Birds Provide Evidence for Adverse Impacts of Climate Change on High-Altitude Species

    PubMed Central

    Flousek, Jiří; Telenský, Tomáš; Hanzelka, Jan; Reif, Jiří

    2015-01-01

    Climate change is among the most important global threats to biodiversity and mountain areas are supposed to be under especially high pressure. Although recent modelling studies suggest considerable future range contractions of montane species accompanied with increased extinction risk, data allowing to test actual population consequences of the observed climate changes and identifying traits associated to their adverse impacts are very scarce. To fill this knowledge gap, we estimated long-term population trends of montane birds from 1984 to 2011 in a central European mountain range, the Giant Mountains (Krkonoše), where significant warming occurred over this period. We then related the population trends to several species' traits related to the climate change effects. We found that the species breeding in various habitats at higher altitudes had more negative trends than species breeding at lower altitudes. We also found that the species moved upwards as a response to warming climate, and these altitudinal range shifts were associated with more positive population trends at lower altitudes than at higher altitudes. Moreover, long-distance migrants declined more than residents or species migrating for shorter distances. Taken together, these results indicate that the climate change, besides other possible environmental changes, already influences populations of montane birds with particularly adverse impacts on high-altitude species such as water pipit (Anthus spinoletta). It is evident that the alpine species, predicted to undergo serious climatically induced range contractions due to warming climate in the future, already started moving along this trajectory. PMID:26426901

  18. Current land bird distribution and trends in population abundance between 1982 and 2012 on Rota, Mariana Islands

    USGS Publications Warehouse

    Camp, Richard J.; Brinck, Kevin W.; Gorresen, P. Marcos; Amidon, Fred A.; Radley, Paul M.; Berkowitz, S. Paul; Banko, Paul C.

    2015-01-01

    The western Pacific island of Rota is the fourth largest human-inhabited island in the Mariana archipelago and designated an Endemic Bird Area. Between 1982 and 2012, 12 point-transect distance-sampling surveys were conducted to assess bird population status. Surveys did not consistently sample the entire island; thus, we used a ratio estimator to estimate bird abundances in strata not sampled during every survey. Trends in population size were reliably estimated for 11 of 13 bird species, and 7 species declined over the 30-y time series, including the island collared-dove Streptopelia bitorquata, white-throated ground-dove Gallicolumba xanthonura, Mariana fruit-dove Ptilinopus roseicapilla, collared kingfisher Todiramphus chloris orii, Micronesian myzomela Myzomela rubratra, black drongo Dicrurus macrocercus, and Mariana crow Corvus kubaryi. The endangered Mariana crow (x̄  =  81 birds, 95% CI 30–202) declined sharply to fewer than 200 individuals in 2012, down from 1,491 birds in 1982 (95% CI  =  815–3,115). Trends increased for white tern Gygis alba, rufous fantail Rhipidura rufifrons mariae, and Micronesian starling Aplonis opaca. Numbers of the endangered Rota white-eye Zosterops rotensis declined from 1982 to the late 1990s but returned to 1980s levels by 2012, resulting in an overall stable trend. Trends for the yellow bittern Ixobrychus sinensis were inconclusive. Eurasian tree sparrow Passer montanus trends were not assessed; however, their numbers in 1982 and 2012 were similar. Occupancy models of the 2012 survey data revealed general patterns of land cover use and detectability among 12 species that could be reliably modeled. Occupancy was not assessed for the Eurasian tree sparrow because of insufficient detections. Based on the 2012 survey, bird distribution and abundance across Rota revealed three general patterns: 1) range restriction, including Mariana crow, Rota white-eye, and Eurasian tree sparrow; 2) widespread distribution, low

  19. Population trends of the loggerhead shrike from the North American Breeding Bird Survey

    USGS Publications Warehouse

    Peterjohn, B.G.; Sauer, J.R.

    1995-01-01

    North American Breeding Bird Survey data indicated a general decline in Loggerhead Shrike (Lanius ludovicianus) populations during 1966-1993. At the continental level, shrikes declined at an average rate of 2.9% per year. Average rates of regional declines varied from 2.5-3.4% annually. These declines were prevalent in most states, provinces, and physiographic strata. Only the Edwards Plateau, High Plains, and Great Plains Roughlands strata, and Colorado, Louisiana, Montana, and South Dakota apparently have stable breeding populations. Severe winter weather during 1976-1979 may have contributed to this decline in the eastern half of the continent, combining with other factors during the winter and breeding seasons that have been implicated in the rangewide decline of this species.

  20. Northern bobwhite, gray partridge, and ring-necked pheasant population trends (1966-1988) from the North American Breeding Bird Survey

    USGS Publications Warehouse

    Droege, S.; Sauer, J.R.

    1990-01-01

    We use North American Breeding Bird Survey data to estimate population trends for 1966-1988 for northern bobwhite (Colinus virginianus), ring-necked pheasant (Phasianus colchicus), and gray partridge (Perdix perdix). Bobwhite populations have undergone widespread declines, pheasant have undergone major declines in eastern North America with mixed trends elsewhere, gray partridge have undergone primarily population increases. We present suggestions for further uses of these data.

  1. Population status of North American grassland birds from the North American Breeding Bird Survey

    USGS Publications Warehouse

    Peterjohn, B.; Sauer, J.R.

    1999-01-01

    We summarize population trends for grassland birds from 1966 to 1996 using data from the North American Breeding Bird Survey. Collectively, grassland birds showed the smallest percentage of species that increased of any Breeding Bird Survey bird group, and population declines prevailed throughout most of North America. Although 3 grassland bird species experienced significant population increases between 1966 and 1996, 13 species declined significantly and 9 exhibited non-significant trend estimates. We summarize the temporal and geographic patterns of the trends for grassland bird species and discuss factors that have contributed to these trends.

  2. Population trends of grassland birds in North America are linked to the prevalence of an agricultural epizootic in Europe.

    PubMed

    Nocera, Joseph J; Koslowsky, Hannah M

    2011-03-22

    Globalization of trade has dramatic socioeconomic effects, and, intuitively, significant ecological effects should follow. However, few quantitative examples exist of the interrelationship of globalization, socioeconomics, and ecological patterns. We present a striking illustration of a cascade in which bovine spongiform encephalopathy (BSE; "mad cow disease") outbreaks in Europe exerted pressure on global beef markets, subsequently affecting North American hayfields and grassland bird populations. We examined competing models, which linked the prevalence of BSE in five focal countries, volume of beef exports to those countries from North America, and the amount of hayfield harvested and the abundance of grassland birds in North America. We found that (i) imports from North America increased 1 y after BSE outbreaks; (ii) probably because fewer cattle remained, the hay harvest in North America was reduced 2 y after the outbreak; (iii) the reduced hay harvest yielded a positive response in grassland bird populations 3 y after the outbreak. PMID:21383197

  3. Population trends of grassland birds in North America are linked to the prevalence of an agricultural epizootic in Europe

    PubMed Central

    Nocera, Joseph J.; Koslowsky, Hannah M.

    2011-01-01

    Globalization of trade has dramatic socioeconomic effects, and, intuitively, significant ecological effects should follow. However, few quantitative examples exist of the interrelationship of globalization, socioeconomics, and ecological patterns. We present a striking illustration of a cascade in which bovine spongiform encephalopathy (BSE; “mad cow disease”) outbreaks in Europe exerted pressure on global beef markets, subsequently affecting North American hayfields and grassland bird populations. We examined competing models, which linked the prevalence of BSE in five focal countries, volume of beef exports to those countries from North America, and the amount of hayfield harvested and the abundance of grassland birds in North America. We found that (i) imports from North America increased 1 y after BSE outbreaks; (ii) probably because fewer cattle remained, the hay harvest in North America was reduced 2 y after the outbreak; (iii) the reduced hay harvest yielded a positive response in grassland bird populations 3 y after the outbreak. PMID:21383197

  4. Change Points in the Population Trends of Aerial-Insectivorous Birds in North America: Synchronized in Time across Species and Regions.

    PubMed

    Smith, Adam C; Hudson, Marie-Anne R; Downes, Constance M; Francis, Charles M

    2015-01-01

    North American populations of aerial insectivorous birds are in steep decline. Aerial insectivores (AI) are a group of bird species that feed almost exclusively on insects in flight, and include swallows, swifts, nightjars, and flycatchers. The causes of the declines are not well understood. Indeed, it is not clear when the declines began, or whether the declines are shared across all species in the group (e.g., caused by changes in flying insect populations) or specific to each species (e.g., caused by changes in species' breeding habitat). A recent study suggested that population trends of aerial insectivores changed for the worse in the 1980s. If there was such a change point in trends of the group, understanding its timing and geographic pattern could help identify potential causes of the decline. We used a hierarchical Bayesian, penalized regression spline, change point model to estimate group-level change points in the trends of 22 species of AI, across 153 geographic strata of North America. We found evidence for group-level change points in 85% of the strata. Change points for flycatchers (FC) were distinct from those for swallows, swifts and nightjars (SSN) across North America, except in the Northeast, where all AI shared the same group-level change points. During the 1980s, there was a negative change point across most of North America, in the trends of SSN. For FC, the group-level change points were more geographically variable, and in many regions there were two: a positive change point followed by a negative change point. This group-level synchrony in AI population trends is likely evidence of a response to a common environmental factor(s) with similar effects on many species across broad spatial extents. The timing and geographic patterns of the change points that we identify here should provide a spring-board for research into the causes behind aerial insectivore declines. PMID:26147572

  5. Change Points in the Population Trends of Aerial-Insectivorous Birds in North America: Synchronized in Time across Species and Regions

    PubMed Central

    Smith, Adam C.; Hudson, Marie-Anne R.; Downes, Constance M.; Francis, Charles M.

    2015-01-01

    North American populations of aerial insectivorous birds are in steep decline. Aerial insectivores (AI) are a group of bird species that feed almost exclusively on insects in flight, and include swallows, swifts, nightjars, and flycatchers. The causes of the declines are not well understood. Indeed, it is not clear when the declines began, or whether the declines are shared across all species in the group (e.g., caused by changes in flying insect populations) or specific to each species (e.g., caused by changes in species’ breeding habitat). A recent study suggested that population trends of aerial insectivores changed for the worse in the 1980s. If there was such a change point in trends of the group, understanding its timing and geographic pattern could help identify potential causes of the decline. We used a hierarchical Bayesian, penalized regression spline, change point model to estimate group-level change points in the trends of 22 species of AI, across 153 geographic strata of North America. We found evidence for group-level change points in 85% of the strata. Change points for flycatchers (FC) were distinct from those for swallows, swifts and nightjars (SSN) across North America, except in the Northeast, where all AI shared the same group-level change points. During the 1980s, there was a negative change point across most of North America, in the trends of SSN. For FC, the group-level change points were more geographically variable, and in many regions there were two: a positive change point followed by a negative change point. This group-level synchrony in AI population trends is likely evidence of a response to a common environmental factor(s) with similar effects on many species across broad spatial extents. The timing and geographic patterns of the change points that we identify here should provide a spring-board for research into the causes behind aerial insectivore declines. PMID:26147572

  6. Access to bird population data

    USGS Publications Warehouse

    Martin, E.; Peterjohn, B.G.; Koneff, M.D.

    2001-01-01

    Access to bird population data is critical for effective conservation planning and implementation. Although a tremendous volume of baseline data exists, it is often diffusely distributed and inaccessible to the resource manager and decision maker. A mechanism that facilitates assembly, documentation and delivery of avian data in a user-friendly manner is needed in order to integrate bird-related information resources across agencies and organizations. To address this fundamental need, the National Biological Information Infrastructure (NBII), in partnership with the U.S. Geological Survey's Patuxent Wildlife Research Center and the U.S. Fish and Wildlife Service, is developing a web-based interactive system that will focus on access to bird population and habitat data used in bird management and conservation. This system, known as the NBII Bird Conservation Node, will support planning and evaluation of bird conservation activities within the context of the North American Bird Conservation Initiative (NABCI), a framework for collaboration among organizations interested in bird conservation across North America. Initial development of the NBII Bird Conservation Node will focus on creating a prototype mapping application that will provide interactive access to data from the North American Breeding Bird Survey, the Colonial Waterbird Survey, the Breeding Waterfowl Population and Habitat Survey, and the Atlantic Flyway Mid-winter Waterfowl Survey. This prototype mapping application, to be available on-line at http://www.nbii.gov by Sep 2001, will lay the foundation for establishment of a Migratory Bird Data Center at Patuxent Wildlife Research Center, and will provide an opportunity for linking to and establishing partnerships with other sources of bird population and habitat data available over the Internet.

  7. Monitoring bird populations with Breeding Bird Survey and atlas data

    USGS Publications Warehouse

    Robbins, C.S.; Droege, S.; Sauer, J.R.

    1989-01-01

    The principal means of monitoring avian species in North America since 1966 is the Breeding Bird Survey (BBS). Nearly 2000 random roadside rouleS of 50 3-minule stops each are run once each summer by experienced observers. Two-year and 10ng-lerm population trends have been calculated for 250 of the more common species. We show how Breeding Bird Atlas dala for lWO periods of time can also be used to calculale population nends, and we compare atlas neRds with those from the BBS. If coverage is inlensive and consistent belWeen time periods, atlas dala may be useful for monitoring species that are not adequalely sampled by the BBS.

  8. Marine bird and sea otter population abundance of Prince william sound, Alaska: Trends following the t/v Exxon Valdez oil spill, 1989-93. Restoration project 93045. Exxon Valdez oil spill restoration project final report

    SciTech Connect

    Agler, B.A.; Seiser, P.E.; Kendall, S.J.; Irons, D.B.

    1994-05-01

    We conducted small boat surveys to estimate marine bird and sea otter (Enhdra lutris) populations in Prince William Sound, Alaska during March and July 1993, using methods developed for the 1989-91 surveys (Klosiewski and Laing 1994). During 1993, we recorded 65 birds and 13 mammal species. We estimated that 402,760 + or - 167,697 marine birds were in the Sound during March 1993, an increase of >200,000 birds over 1990 and 1991. To examine trends in our marine bird population estimates from 1989-93, we assumed that in the absence of oil spill effects, population estimates in the oiled zone would change at the same rate as those in the unoiled zone. For Prince William Sound as a whole, we examined population trends from 1989-1993, using regression analyses. We also examined the relative abundance of the species groups seen in Prince William Sound from 1972 to 1993. Sea otter populations in 1993 were estimated at 6,813 + or - 1,861 for March and 8,216 + or - 2,435 for July. We found no difference in the rate of change between the oiled and unoiled zones from 1989-93 for either the March or July population estimates. There was no significant trend in the total number of sea otters in Prince William Sound from 1989-93.

  9. Bias of animal population trend estimates

    USGS Publications Warehouse

    Geissler, P.H.; Link, W.A.

    1988-01-01

    A computer simulation study of the population trend estimator used for the Mourning Dove Call-Count Survey, Woodcock Singing Ground Survey, Breeding Bird Survey and other surveys concluded that the estimator had negligible bias in most situations but that observer covariables should not be used with less than five years of data. With rare species (e.g. two birds per route), at least five years should be used. The estimator is seriously biased towards not detecting population changes with very rare species (e.g. 0.3 birds per route). Other technical recommendations are made.

  10. Population Trends and Prospects.

    ERIC Educational Resources Information Center

    Mauldin, W. Parker

    1980-01-01

    Future trends in population are described as they relate to developed and developing nations. It is suggested that for the next 20 years there will be a decrease in population growth rates for all areas of the world except Africa. (Author/SA)

  11. Use of North American Breeding Bird Survey data to estimate population change for bird conservation regions

    USGS Publications Warehouse

    Sauer, J.R.; Fallon, J.E.; Johnson, R.

    2003-01-01

    Conservation planning requires information at a variety of geographic scales, and it is often unclear whether surveys designed for other purposes will provide appropriate information for management at various scales. We evaluated the use of the North American Breeding Bird Survey (BBS) to meet information needs for conservation planning in Bird Conservation Regions (BCRs). The BBS originally was developed to provide regional estimates for states, provinces, physiographic regions, and larger areas. Many analyses have used physiographic regions within states/provinces as strata. We evaluated potential consequences of using BCRs instead of the BBS physiographic regions, testing for spatial differences in sample intensity within states and provinces. We reclassified the BBS survey routes to BCRs and conducted route regression trend (interval-specific population change) analyses for a variety of regions and time intervals. Our results were similar to those based on traditional BBS regions and suggest minimal consequences of the reclassification for the BBS sample. We summarized population change within BCRs and assessed the efficiency of the BBS in estimating population change for 421 species surveyed. As would be expected from an omnibus survey, many species appeared to be poorly monitored by the BBS, with 42% of species encountered at <1 bird per route from the survey, and 28% of trend estimates too imprecise to detect a 3% per year change over 35 years. Our results indicated that the quality of the survey for estimation of population change varied among BCRs. Population trends of species were heterogeneous over space and time, varying among BCRs for 76% of species and over time for 39% of species. Regional heterogeneity also existed in trends of species groups from the BBS. While 49% of all species in the survey had increasing populations, grassland breeding birds showed consistent declines, with only 18% of species having positive trend estimates. Bird Conservation

  12. Can Ingestion of Lead Shot and Poisons Change Population Trends of Three European Birds: Grey Partridge, Common Buzzard, and Red Kite?

    PubMed Central

    Meyer, Carolyn B.; Meyer, Joseph S.; Francisco, Alex B.; Holder, Jennifer; Verdonck, Frederik

    2016-01-01

    Little is known about the magnitude of the effects of lead shot ingestion alone or combined with poisons (e.g., in bait or seeds/granules containing pesticides) on population size, growth, and extinction of non-waterbird avian species that ingest these substances. We used population models to create example scenarios demonstrating how changes in these parameters might affect three susceptible species: grey partridge (Perdix perdix), common buzzard (Buteo buteo), and red kite (Milvus milvus). We added or subtracted estimates of mortality due to lead shot ingestion (4–16% of mortality, depending on species) and poisons (4–46% of mortality) reported in the UK or France to observed mortality of studied populations after models were calibrated to observed population trends. Observed trends were decreasing for partridge (in continental Europe), stable for buzzard (in Germany), and increasing for red kite (in Wales). Although lead shot ingestion and poison at modeled levels did not change the trend direction for the three species, they reduced population size and slowed population growth. Lead shot ingestion at modeled rates reduced population size of partridges by 10%, and when combined with bait and pesticide poisons, by 18%. For buzzards, decrease in mean population size by lead shot and poisons combined was much smaller (≤ 1%). The red kite population has been recovering; however, modeled lead shot ingestion reduced its annual growth rate from 6.5% to 4%, slowing recovery. If mortality from poisoned baits could be removed, the kite population could potentially increase at a rapid annual rate of 12%. The effects are somewhat higher if ingestion of these substances additionally causes sublethal reproductive impairment. These results have uncertainty but suggest that declining or recovering populations are most sensitive to lead shot or poison ingestion, and removal of poisoned baits can have a positive impact on recovering raptor populations that frequently feed

  13. Can Ingestion of Lead Shot and Poisons Change Population Trends of Three European Birds: Grey Partridge, Common Buzzard, and Red Kite?

    PubMed

    Meyer, Carolyn B; Meyer, Joseph S; Francisco, Alex B; Holder, Jennifer; Verdonck, Frederik

    2016-01-01

    Little is known about the magnitude of the effects of lead shot ingestion alone or combined with poisons (e.g., in bait or seeds/granules containing pesticides) on population size, growth, and extinction of non-waterbird avian species that ingest these substances. We used population models to create example scenarios demonstrating how changes in these parameters might affect three susceptible species: grey partridge (Perdix perdix), common buzzard (Buteo buteo), and red kite (Milvus milvus). We added or subtracted estimates of mortality due to lead shot ingestion (4-16% of mortality, depending on species) and poisons (4-46% of mortality) reported in the UK or France to observed mortality of studied populations after models were calibrated to observed population trends. Observed trends were decreasing for partridge (in continental Europe), stable for buzzard (in Germany), and increasing for red kite (in Wales). Although lead shot ingestion and poison at modeled levels did not change the trend direction for the three species, they reduced population size and slowed population growth. Lead shot ingestion at modeled rates reduced population size of partridges by 10%, and when combined with bait and pesticide poisons, by 18%. For buzzards, decrease in mean population size by lead shot and poisons combined was much smaller (≤ 1%). The red kite population has been recovering; however, modeled lead shot ingestion reduced its annual growth rate from 6.5% to 4%, slowing recovery. If mortality from poisoned baits could be removed, the kite population could potentially increase at a rapid annual rate of 12%. The effects are somewhat higher if ingestion of these substances additionally causes sublethal reproductive impairment. These results have uncertainty but suggest that declining or recovering populations are most sensitive to lead shot or poison ingestion, and removal of poisoned baits can have a positive impact on recovering raptor populations that frequently feed on

  14. Winter bird population studies and project prairie birds for surveying grassland birds

    USGS Publications Warehouse

    Twedt, D.J.; Hamel, P.B.; Woodrey, M.S.

    2008-01-01

    We compared 2 survey methods for assessing winter bird communities in temperate grasslands: Winter Bird Population Study surveys are area-searches that have long been used in a variety of habitats whereas Project Prairie Bird surveys employ active-flushing techniques on strip-transects and are intended for use in grasslands. We used both methods to survey birds on 14 herbaceous reforested sites and 9 coastal pine savannas during winter and compared resultant estimates of species richness and relative abundance. These techniques did not yield similar estimates of avian populations. We found Winter Bird Population Studies consistently produced higher estimates of species richness, whereas Project Prairie Birds produced higher estimates of avian abundance for some species. When it is important to identify all species within the winter bird community, Winter Bird Population Studies should be the survey method of choice. If estimates of the abundance of relatively secretive grassland bird species are desired, the use of Project Prairie Birds protocols is warranted. However, we suggest that both survey techniques, as currently employed, are deficient and recommend distance- based survey methods that provide species-specific estimates of detection probabilities be incorporated into these survey methods.

  15. Killdeer population trends in North America

    USGS Publications Warehouse

    Sanzenbacher, Peter; Haig, Susan M.

    2001-01-01

    Killdeers (Charadrius vociferus) are considered a common species that inhabits a wide range of wetland and upland habitats throughout much of North America, yet recent information suggests that they may be declining regionally, if not throughout much of their range. To address this issue, we examined population trends of this species at multiple spatial and temporal scales using data from two major avian survey efforts, the Breeding Bird Survey (BBS) and Christmas Bird Count (CBC). A summary of BBS trends indicates significant long-term (1966a??1996) declines in breeding populations across North America. Geographic regions driving this decline were Canada, western survey regions of the continent, and select southeastern states. In contrast, over the same time period, Killdeer populations increased in some midwestern states, particularly those in the Great Lakes region. Recent BBS trends (1986a??1996) indicate highly significant declines across most areas of North America surveyed. Trends from CBC data (1959a??1988) indicate declines at a smaller spatial scale. While the ability of current major avian survey efforts to detect population trends for Killdeer and other shorebird species warrants further examination, significant negative trends in Killdeer populations indicates the need to further investigate the status of this species.

  16. Agricultural intensification and the collapse of Europe's farmland bird populations.

    PubMed

    Donal, P F; Gree, R E; Heath, M F

    2001-01-01

    The populations of farmland birds in Europe declined markedly during the last quarter of the 20th century, representing a severe threat to biodiversity. Here, we assess whether declines in the populations and ranges of farmland birds across Europe reflect differences in agricultural intensity, which arise largely through differences in political history. Population and range changes were modelled in terms of a number of indices of agricultural intensity. Population declines and range contractions were significantly greater in countries with more intensive agriculture, and significantly higher in the European Union (EU) than in former communist countries. Cereal yield alone explained over 30% of the variation in population trends. The results suggest that recent trends in agriculture have had deleterious and measurable effects on bird populations on a continental scale. We predict that the introduction of EU agricultural policies into former communist countries hoping to accede to the EU in the near future will result in significant declines in the important bird populations there. PMID:12123294

  17. [Population trends and poverty].

    PubMed

    Olmedo, C

    1998-04-01

    Implications of population growth in Ecuador for the quality of life of the poor population are analyzed. It is argued that if the gross national product (GNP) were to grow at a sustained annual rate of 5% or more, demographic trends would not present a significant obstacle to reducing poverty. National economic projections are for growth of only 2.5-3.5% annually. The continuing rapid growth of the poor population despite general slowing of demographic growth, the young age structure, the need for increased formal education to enable the poor to overcome their poverty, and the effect of unemployment on the dependency ratio will tend to hamper improvements in average productivity and per capita GNP. The need for spending on education, health, basic services, and housing will divert funds away from productive investment, generating a direct negative impact on economic growth. Over half of Ecuadorian children suffer from some degree of malnutrition, indicating that food production is inadequate to meet demand. The export-oriented agricultural policy and poor weather have led to a chronic shortage of basic foods. Progressive increase and diversification of agricultural production, along with maintenance of low prices and substantial increases in income levels and agricultural productivity, will be required if the entire population is to be fed adequately. Intense efforts will be needed from all sectors to bring demographic growth into balance with economic and development needs. PMID:12178231

  18. Migratory diversity predicts population declines in birds.

    PubMed

    Gilroy, James J; Gill, Jennifer A; Butchart, Stuart H M; Jones, Victoria R; Franco, Aldina M A

    2016-03-01

    Declines in migratory species are a pressing concern worldwide, but the mechanisms underpinning these declines are not fully understood. We hypothesised that species with greater within-population variability in migratory movements and destinations, here termed 'migratory diversity', might be more resilient to environmental change. To test this, we related map-based metrics of migratory diversity to recent population trends for 340 European breeding birds. Species that occupy larger non-breeding ranges relative to breeding, a characteristic we term 'migratory dispersion', were less likely to be declining than those with more restricted non-breeding ranges. Species with partial migration strategies (i.e. overlapping breeding and non-breeding ranges) were also less likely to be declining than full migrants or full residents, an effect that was independent of migration distance. Recent rates of advancement in Europe-wide spring arrival date were greater for partial migrants than full migrants, suggesting that migratory diversity may also help facilitate species responses to climate change. PMID:26807694

  19. Estimating population trends with a linear model

    USGS Publications Warehouse

    Bart, J.; Collins, B.; Morrison, R.I.G.

    2003-01-01

    We describe a simple and robust method for estimating trends in population size. The method may be used with Breeding Bird Survey data, aerial surveys, point counts, or any other program of repeated surveys at permanent locations. Surveys need not be made at each location during each survey period. The method differs from most existing methods in being design based, rather than model based. The only assumptions are that the nominal sampling plan is followed and that sample size is large enough for use of the t-distribution. Simulations based on two bird data sets from natural populations showed that the point estimate produced by the linear model was essentially unbiased even when counts varied substantially and 25% of the complete data set was missing. The estimating-equation approach, often used to analyze Breeding Bird Survey data, performed similarly on one data set but had substantial bias on the second data set, in which counts were highly variable. The advantages of the linear model are its simplicity, flexibility, and that it is self-weighting. A user-friendly computer program to carry out the calculations is available from the senior author.

  20. Population and habitat assessment: Monitoring bird populations over large areas: Introduction

    USGS Publications Warehouse

    Sauer, J.R.; Cooper, R.J.

    2000-01-01

    Monitoring provides essential information about status and change in bird populations. For Neotropical Migrant Birds (NTMBs), the North American Breeding Bird Survey (BBS) has been particularly influential in documenting regional population change and often is cited as justification for management actions. However, as with most bird surveys, the design of the BBS, and the geographic scale of the information, often limits its use either in evaluating the response of bird populations to management, or in identifying causes of population change.

  1. Monitoring grizzly bear population trends

    USGS Publications Warehouse

    Eberhardt, L.L.; Knight, R.R.; Blanchard, B.M.

    1986-01-01

    A simple different equation model was developed to provide additional perspective on observed mortality and trend data on Yellowstone grizzly bears (Ursus arctos horribilis). Records of mortalities of adult females from 1959 to 1985 were utilized, in conjunction with data on females with cubs. The overall downward trend of observed numbers of females with cubs generally agrees with the model calculations but does not adequately reflect mortality from 1970 to 1974. The model may be useful in developing a composite index of population trend.

  2. BirdVis: visualizing and understanding bird populations.

    PubMed

    Ferreira, Nivan; Lins, Lauro; Fink, Daniel; Kelling, Steve; Wood, Chris; Freire, Juliana; Silva, Cláudio

    2011-12-01

    Birds are unrivaled windows into biotic processes at all levels and are proven indicators of ecological well-being. Understanding the determinants of species distributions and their dynamics is an important aspect of ecology and is critical for conservation and management. Through crowdsourcing, since 2002, the eBird project has been collecting bird observation records. These observations, together with local-scale environmental covariates such as climate, habitat, and vegetation phenology have been a valuable resource for a global community of educators, land managers, ornithologists, and conservation biologists. By associating environmental inputs with observed patterns of bird occurrence, predictive models have been developed that provide a statistical framework to harness available data for predicting species distributions and making inferences about species-habitat associations. Understanding these models, however, is challenging because they require scientists to quantify and compare multiscale spatialtemporal patterns. A large series of coordinated or sequential plots must be generated, individually programmed, and manually composed for analysis. This hampers the exploration and is a barrier to making the cross-species comparisons that are essential for coordinating conservation and extracting important ecological information. To address these limitations, as part of a collaboration among computer scientists, statisticians, biologists and ornithologists, we have developed BirdVis, an interactive visualization system that supports the analysis of spatio-temporal bird distribution models. BirdVis leverages visualization techniques and uses them in a novel way to better assist users in the exploration of interdependencies among model parameters. Furthermore, the system allows for comparative visualization through coordinated views, providing an intuitive interface to identify relevant correlations and patterns. We justify our design decisions and present case

  3. Modern population trends in Bangladesh.

    PubMed

    Abul-basher, M M

    1985-01-01

    Population growth trends in Bangladesh in the 1871-1981 period were analyzed, with emphasis on fertility and mortality differentials, to provide a basis for population planning. Following proclamation of British Imperial Rule in 1857, mortality rates in Bangladesh began to decline as a result of preventive measures against natural disasters such as draught and famine, but the fertility rate remained unaltered. The demographic pattern was unstable over time, reflecting the impact of the influenza epidemic of 1918-19, war, migration, and economic development. Population growth accelerated greatly during the 1961-74 period, when industrialization emerged and job opportunities were created in the urban centers. Economic hardship, food shortages, and the introduction of family planning curbed urban growth drastically and total growth to some extent in 1974-81. On the average, growth has been higher in the Dhaka and Chittagong Divisions of Bangladesh than in the Khulna and Rajshahi Divisions. Differences in population growth among the regions are attributable largely to internal and external migration. The regression polynomial model best fits past population trends in Bangladesh and can reproduce the observed population by 99.60%. This polynomial is most suitable for graduation and prediction of population trends. PMID:12280834

  4. Power to detect trends in abundance of secretive marsh birds: effects of species traits and sampling effort

    USGS Publications Warehouse

    Steidl, Robert J.; Conway, Courtney J.; Litt, Andrea R.

    2013-01-01

    Standardized protocols for surveying secretive marsh birds have been implemented across North America, but the efficacy of surveys to detect population trends has not been evaluated. We used survey data collected from populations of marsh birds across North America and simulations to explore how characteristics of bird populations (proportion of survey stations occupied, abundance at occupied stations, and detection probability) and aspects of sampling effort (numbers of survey routes, stations/route, and surveys/station/year) affect statistical power to detect trends in abundance of marsh bird populations. In general, the proportion of survey stations along a route occupied by a species had a greater relative effect on power to detect trends than did the number of birds detected per survey at occupied stations. Uncertainty introduced by imperfect detection during surveys reduced power to detect trends considerably, but across the range of detection probabilities for most species of marsh birds, variation in detection probability had only a minor influence on power. For species that occupy a relatively high proportion of survey stations (0.20), have relatively high abundances at occupied stations (2.0 birds/station), and have high detection probability (0.50), ≥40 routes with 10 survey stations per route surveyed 3 times per year would provide an 80% chance of detecting a 3% annual decrease in abundance after 20 years of surveys. Under the same assumptions but for species that are less common, ≥100 routes would be needed to achieve the same power. Our results can help inform the design of programs to monitor trends in abundance of marsh bird populations, especially with regards to the amount of sampling effort necessary to meet programmatic goals.

  5. Modeling trends from North American Breeding Bird Survey data: a spatially explicit approach

    USGS Publications Warehouse

    Bled, Florent; Sauer, John R.; Pardieck, Keith L.; Doherty, Paul; Royle, J. Andy

    2013-01-01

    Population trends, defined as interval-specific proportional changes in population size, are often used to help identify species of conservation interest. Efficient modeling of such trends depends on the consideration of the correlation of population changes with key spatial and environmental covariates. This can provide insights into causal mechanisms and allow spatially explicit summaries at scales that are of interest to management agencies. We expand the hierarchical modeling framework used in the North American Breeding Bird Survey (BBS) by developing a spatially explicit model of temporal trend using a conditional autoregressive (CAR) model. By adopting a formal spatial model for abundance, we produce spatially explicit abundance and trend estimates. Analyses based on large-scale geographic strata such as Bird Conservation Regions (BCR) can suffer from basic imbalances in spatial sampling. Our approach addresses this issue by providing an explicit weighting based on the fundamental sample allocation unit of the BBS. We applied the spatial model to three species from the BBS. Species have been chosen based upon their well-known population change patterns, which allows us to evaluate the quality of our model and the biological meaning of our estimates. We also compare our results with the ones obtained for BCRs using a nonspatial hierarchical model (Sauer and Link 2011). Globally, estimates for mean trends are consistent between the two approaches but spatial estimates provide much more precise trend estimates in regions on the edges of species ranges that were poorly estimated in non-spatial analyses. Incorporating a spatial component in the analysis not only allows us to obtain relevant and biologically meaningful estimates for population trends, but also enables us to provide a flexible framework in order to obtain trend estimates for any area.

  6. Bird population density estimated from acoustic signals

    USGS Publications Warehouse

    Dawson, D.K.; Efford, M.G.

    2009-01-01

    Many animal species are detected primarily by sound. Although songs, calls and other sounds are often used for population assessment, as in bird point counts and hydrophone surveys of cetaceans, there are few rigorous methods for estimating population density from acoustic data. 2. The problem has several parts - distinguishing individuals, adjusting for individuals that are missed, and adjusting for the area sampled. Spatially explicit capture-recapture (SECR) is a statistical methodology that addresses jointly the second and third parts of the problem. We have extended SECR to use uncalibrated information from acoustic signals on the distance to each source. 3. We applied this extension of SECR to data from an acoustic survey of ovenbird Seiurus aurocapilla density in an eastern US deciduous forest with multiple four-microphone arrays. We modelled average power from spectrograms of ovenbird songs measured within a window of 0??7 s duration and frequencies between 4200 and 5200 Hz. 4. The resulting estimates of the density of singing males (0??19 ha -1 SE 0??03 ha-1) were consistent with estimates of the adult male population density from mist-netting (0??36 ha-1 SE 0??12 ha-1). The fitted model predicts sound attenuation of 0??11 dB m-1 (SE 0??01 dB m-1) in excess of losses from spherical spreading. 5.Synthesis and applications. Our method for estimating animal population density from acoustic signals fills a gap in the census methods available for visually cryptic but vocal taxa, including many species of bird and cetacean. The necessary equipment is simple and readily available; as few as two microphones may provide adequate estimates, given spatial replication. The method requires that individuals detected at the same place are acoustically distinguishable and all individuals vocalize during the recording interval, or that the per capita rate of vocalization is known. We believe these requirements can be met, with suitable field methods, for a significant

  7. Evaluation of Two Methods to Estimate and Monitor Bird Populations

    PubMed Central

    Taylor, Sandra L.; Pollard, Katherine S.

    2008-01-01

    Background Effective management depends upon accurately estimating trends in abundance of bird populations over time, and in some cases estimating abundance. Two population estimation methods, double observer (DO) and double sampling (DS), have been advocated for avian population studies and the relative merits and short-comings of these methods remain an area of debate. Methodology/Principal Findings We used simulations to evaluate the performances of these two population estimation methods under a range of realistic scenarios. For three hypothetical populations with different levels of clustering, we generated DO and DS population size estimates for a range of detection probabilities and survey proportions. Population estimates for both methods were centered on the true population size for all levels of population clustering and survey proportions when detection probabilities were greater than 20%. The DO method underestimated the population at detection probabilities less than 30% whereas the DS method remained essentially unbiased. The coverage probability of 95% confidence intervals for population estimates was slightly less than the nominal level for the DS method but was substantially below the nominal level for the DO method at high detection probabilities. Differences in observer detection probabilities did not affect the accuracy and precision of population estimates of the DO method. Population estimates for the DS method remained unbiased as the proportion of units intensively surveyed changed, but the variance of the estimates decreased with increasing proportion intensively surveyed. Conclusions/Significance The DO and DS methods can be applied in many different settings and our evaluations provide important information on the performance of these two methods that can assist researchers in selecting the method most appropriate for their particular needs. PMID:18728775

  8. Temporal Trends in Metal Pollution: Using Bird Excrement as Indicator

    PubMed Central

    Berglund, Åsa M. M.; Rainio, Miia J.; Eeva, Tapio

    2015-01-01

    Past mining and smelting activities have resulted in metal polluted environments all over the world, but long-term monitoring data is often scarce, especially in higher trophic levels. In this study we used bird (Parus major and Ficedula hypoleuca) excrement to monitor metal pollution in the terrestrial environment following 16 years of continuously reduced emissions from a copper/nickel smelter in Finland. In the early 1990s, lead and cadmium concentrations dropped significantly in excrement, but the reduction did not directly reflect the changes in atmospheric emission from the smelter. This is likely due to a continuous contribution of metals also from the soil pool. We conclude that bird excrement can be used to assess changes in the environment as a whole but not specifically changes in atmospheric emission. Inter-annual variation in excrement concentration of especially copper and nickel demonstrates the importance of long-term monitoring to discern significant trends. PMID:25680108

  9. North American Bird Banding and quantitative population ecology

    USGS Publications Warehouse

    Nichols, J.D.; Tautin, J.

    2008-01-01

    Early bird-banding programs in North America were developed to provide descriptions of bird migration and movement patterns. This initial interest in description quickly evolved into more quantitative interests in two ways. There was (1) interest in quantifying migration and movement patterns, and (2) rapid recognition that re-observations of marked birds provided information about other parameters relevant to population dynamics. These included survival rate, recruitment rate, and population size. The evolution of methods for estimating population size, survival, recruitment, and movement is reviewed and we show it to be closely tied to bird-banding data. These estimation methods have been used with bird-banding data to draw important inferences about evolutionary ecology, population ecology, and population management. Illustrative examples of such inferences are provided.

  10. Population trends and management opportunities for neotropical migrants

    USGS Publications Warehouse

    Robbins, C.S.; Sauer, J.R.; Peterjohn, B.G.

    1993-01-01

    The Breeding Bird Survey shows that certain Neotropical migrant songbird populations have been declining over the past 26 years. Among them are forest birds that require extensive forest on the breeding grounds and also forested habitats on tropical wintering grounds. Other species have shown significant declines only since the early 1980's. Birds with broader habitat tolerance, such as those that winter commonly in agricultural and early-successional habitats as well as primary forest, show fewer consistent declines. Several grassland species have also been declining for more than two decades. Populations of many other Neotropical migrants have been stable or increasing over these periods. Examples of 26-year population trends are given. A dozen recommendations are given for managing nesting habitat for Neotropical migrants.

  11. Combining Breeding Bird Survey and Christmas Bird Count data to evaluate seasonal components of population change in Northern Bobwhite

    USGS Publications Warehouse

    Link, W.A.; Sauer, J.R.; Niven, D.K.

    2008-01-01

    Annual surveys of wildlife populations provide information about annual rates of change in populations but provide no information about when such changes occur. However, by combining data from 2 annual surveys, conducted in different parts of the year, seasonal components of population change can be estimated. We describe a hierarchical model for simultaneous analysis of 2 continent-scale monitoring programs. The Christmas Bird Count is an early winter survey, whereas the North American Breeding Bird Survey is conducted in June. Combining information from these surveys permits estimation of seasonal population variance components and improves estimation of long-term population trends. The composite analysis also controls for survey-specific sampling effects. We applied the model to estimation of population change in northern bobwhites (Colinus virginianus). Over the interval 1969?2004, bobwhite populations declined, with trend estimate of -3.56% per year (95% CI = [-3.80%, -3.32%]) in the surveyed portion of their range. Our analysis of seasonal population variance components indicated that northern bobwhite populations changed more in the winter and spring portion of the year than in the summer and fall portion of the year.

  12. Bird populations on the Island of Tinian: persistence despite wholesale loss of native forests

    USGS Publications Warehouse

    Camp, Richard J.; Amidon, Frederick A.; Marshall, Ann P.; Pratt, Thane K.

    2012-01-01

    Bird habitat on the island of Tinian, Mariana Islands, has been substantially altered, and only around 5% of the island has native forest today. The modern bird fauna is likely to be a subset of the original avifauna where only species tolerant to native forest loss and human disturbance have survived. Avian surveys were conducted on the island in 2008 by the U.S. Fish and Wildlife Service to provide current densities and abundances of the remaining species, and assess population trends using data collected from previous surveys. During the three surveys (1982, 1996, and 2008), 18 species were detected, and abundances and trends were assessed for 11 species. Five of the nine native species and one alien bird have increased since 1982. Three native birds—Mariana Fruit-Dove (Ptilinopus roseicapilla), Micronesian Honeyeater (Myzomela rubratra), and Tinian Monarch (Monarcha takatsukasae)—have decreased since 1982. Trends for the remaining two birds (one native and one alien) were considered relatively stable. Only five birds, including the Tinian Monarch, showed significant differences among regions of Tinian by year. Increased development on Tinian may result in increases in habitat clearing and expansion of human-dominated habitats, and declines in some bird populations would likely continue or be exacerbated with these actions. Expanded development activities on Tinian would also mean increased cargo movement between Guam and Tinian, elevating the probability of transporting the Brown Tree Snake (Boiga irregularis) to Tinian, which would lead to precipitous decreases and extinctions.

  13. Hawaiian forest bird trends: using log-linear models to assess long-term trends is supported by model diagnostics and assumptions (reply to Freed and Cann 2013)

    USGS Publications Warehouse

    Camp, Richard J.; Pratt, Thane K.; Gorresen, P. Marcos; Woodworth, Bethany L.; Jeffrey, John J.

    2014-01-01

    Freed and Cann (2013) criticized our use of linear models to assess trends in the status of Hawaiian forest birds through time (Camp et al. 2009a, 2009b, 2010) by questioning our sampling scheme, whether we met model assumptions, and whether we ignored short-term changes in the population time series. In the present paper, we address these concerns and reiterate that our results do not support the position of Freed and Cann (2013) that the forest birds in the Hakalau Forest National Wildlife Refuge (NWR) are declining, or that the federally listed endangered birds are showing signs of imminent collapse. On the contrary, our data indicate that the 21-year long-term trends for native birds in Hakalau Forest NWR are stable to increasing, especially in areas that have received active management.

  14. Interannual variation and long-term trends in proportions of resident individuals in partially migratory birds.

    PubMed

    Meller, Kalle; Vähätalo, Anssi V; Hokkanen, Tatu; Rintala, Jukka; Piha, Markus; Lehikoinen, Aleksi

    2016-03-01

    Partial migration - a part of a population migrates and another part stays resident year-round on the breeding site - is probably the most common type of migration in the animal kingdom, yet it has only lately garnered more attention. Theoretical studies indicate that in partially migratory populations, the proportion of resident individuals (PoR) should increase in high latitudes in response to the warming climate, but empirical evidence exists for few species. We provide the first comprehensive overview of the environmental factors affecting PoR and the long-term trends in PoR by studying 27 common partially migratory bird species in Finland. The annual PoR values were calculated by dividing the winter bird abundance by the preceding breeding abundance. First, we analysed whether early-winter temperature, winter temperature year before or the abundance of tree seeds just before overwintering explains the interannual variation in PoR. Secondly, we analysed the trends in PoR between 1987 and 2011. Early-winter temperature explained the interannual variation in PoR in the waterbirds (waterfowl and gulls), most likely because the temperature affects the ice conditions and thereby the feeding opportunities for the waterbirds. In terrestrial species, the abundance of seeds was the best explanatory variable. Previous winter's temperature did not explain PoR in any species, and thus, we conclude that the variation in food availability caused the interannual variation in PoR. During the study period, PoR increased in waterbirds, but did not change in terrestrial birds. Partially migratory species living in physically contrasting habitats can differ in their annual and long-term population-level behavioural responses to warming climate, possibly because warm winter temperatures reduce ice cover and improve the feeding possibilities of waterbirds but do not directly regulate the food availability for terrestrial birds. PMID:26718017

  15. Modeling seasonal interactions in the population dynamics of migratory birds

    USGS Publications Warehouse

    Runge, M.C.; Marra, P.P.

    2005-01-01

    Understanding the population dynamics of migratory birds requires understanding the relevant biological events that occur during breeding, migratory, and overwintering periods. The few available population models for passerine birds focus on breeding-season events, disregard or oversimplify events during nonbreeding periods, and ignore interactions that occur between periods of the annual cycle. Identifying and explicitly incorporating seasonal interactions into population models for migratory birds could provide important insights about when population limitation actually occurs in the annual cycle. We present a population model for the annual cycle of a migratory bird, based on the American Redstart (Setophaga ruticilla) but more generally applicable, that examines the importance of seasonal interactions by incorporating: (1) density dependence during the breeding and winter seasons, (2) a carry-over effect of winter habitat on breeding-season productivity, and (3) the effects of behavioral dominance on seasonal and habitat specific demographic rates. First, we show that habitat availability on both the wintering and breeding grounds can strongly affect equilibrium population size and sex ratio. Second, sex ratio dynamics, as mediated by behavioral dominance, can affect all other aspects of population dynamics. Third, carry-over effects can be strong, especially when winter events are limiting. These results suggest that understanding the population dynamics of migratory birds may require more consideration of the seasonal interactions induced by carry-over effects and density dependence in multiple seasons. This model provides a framework in which to explore more fully these seasonal dynamics and a context for estimation of life history parameters.

  16. Assessing vulnerability of marine bird populations to offshore wind farms.

    PubMed

    Furness, Robert W; Wade, Helen M; Masden, Elizabeth A

    2013-04-15

    Offshore wind farms may affect bird populations through collision mortality and displacement. Given the pressures to develop offshore wind farms, there is an urgent need to assess population-level impacts on protected marine birds. Here we refine an approach to assess aspects of their ecology that influence population vulnerability to wind farm impacts, also taking into account the conservation importance of each species. Flight height appears to be a key factor influencing collision mortality risk but improved data on flight heights of marine birds are needed. Collision index calculations identify populations of gulls, white-tailed eagles, northern gannets and skuas as of particularly high concern in Scottish waters. Displacement index calculations identify populations of divers and common scoters as most vulnerable to population-level impacts of displacement, but these are likely to be less evident than impacts of collision mortality. The collision and displacement indices developed here for Scottish marine bird populations could be applied to populations elsewhere, and this approach will help in identifying likely impacts of future offshore wind farms on marine birds and prioritising monitoring programmes, at least until data on macro-avoidance rates become available. PMID:23454414

  17. Hawaii Forest Bird Interagency Database Project: Collecting, Understanding, and Sharing Population Data on Hawaiian Forest Birds

    USGS Publications Warehouse

    Pratt, Thane K.; Woodworth, Bethany L.; Camp, Richard J.; Gorresen, P. Marcos

    2006-01-01

    The forest birds of the Hawaiian Islands are distinguished by the diversity of endemic forms derived from a small number of ancestral colonists. However, the avifauna has been decimated by human activities both before and after Western contact. At least 71 species or subspecies disappeared before the arrival of Capt. James Cook in 1778, and an additional 24 went extinct after 1778, of which 11 were lost since the 1960s alone. Many of the remaining Hawaiian bird populations are declining or are in danger of extinction. Vigorous efforts to survey and monitor bird populations over the past 3 decades have generated considerable information from which to assess the current status of the Hawaiian forest birds.

  18. Development of a practical modeling framework for estimating the impact of wind technology on bird populations

    SciTech Connect

    Morrison, M.L.; Pollock, K.H.

    1997-11-01

    One of the most pressing environmental concerns related to wind project development is the potential for avian fatalities caused by the turbines. The goal of this project is to develop a useful, practical modeling framework for evaluating potential wind power plant impacts that can be generalized to most bird species. This modeling framework could be used to get a preliminary understanding of the likelihood of significant impacts to birds, in a cost-effective way. The authors accomplish this by (1) reviewing the major factors that can influence the persistence of a wild population; (2) briefly reviewing various models that can aid in estimating population status and trend, including methods of evaluating model structure and performance; (3) reviewing survivorship and population projections; and (4) developing a framework for using models to evaluate the potential impacts of wind development on birds.

  19. Bird population and habitat surveys in urban areas

    USGS Publications Warehouse

    DeGraaf, R.M.; Geis, A.D.; Healy, P.A.

    1991-01-01

    Breeding bird populations in six habitats in Columbia. MD, were studied to develop procedures suitable for measuring bird use of residential areas and to identify habitat characteristics that define the distribution of various common bird species. A procedure to measure bird use based on 4-min transect counts on plots measuring 91 m ? 91 m proved better than point counts. Transect counts reduced many of the problems associated with counting birds in urban areas, such as varying noise and visibility. Eighty percent of observations were recorded in the first 4 min. Habitat measurement procedures were examined also. It was found that a subsample of woody tree and shrub crown volumes made on 0.2 ha was highly correlated with similar measures made on 0.8-ha plots.

  20. Bird populations in relation to changes in land use

    USGS Publications Warehouse

    Warbach, O.

    1958-01-01

    Changes in breeding-bird populations on a 210-acre farm area were observed from 1947 to 1952. During this period, clearing, drainage, and planting changed the area from a partially abandoned farm with only 34 acres in cultivation to a modem conservation farm. Number of bird species nesting in the area was about 10 per cent lower in the last three years than in the first three years; number of nesting pairs declined about 40 per cent. The greatest decline was in species characteristic of brushy habitat; these were the most abundant birds on the area at the start of the study. For these species, approximately eight acres of planted hedges and field borders did not serve as an adequate substitute for 63 acres of brushy fields. Other birds were so limited in number during the breeding season that it is unsafe to conclude what effect agricultural practices had on their populations.

  1. Do Major Roads Reduce Gene Flow in Urban Bird Populations?

    PubMed Central

    Zhang, Shuping; Suo, Mingli; Liu, Shenglin; Liang, Wei

    2013-01-01

    Background Although the negative effects of roads on the genetics of animal populations have been extensively reported, the question of whether roads reduce gene flow in volant, urban bird populations has so far not been addressed. In this study, we assess whether highways decreased gene flow and genetic variation in a small passerine bird, the tree sparrow (Passer montanus). Methodology We assessed genetic differences among tree sparrows (Passer montanus) sampled at 19 sites within Beijing Municipality, China, using 7 DNA microsatellites as genetic markers. Results AMOVA showed that genetic variation between sites, between urban and rural populations, and between opposite sides of the same highway, were very weak. Mantel tests on all samples, and on urban samples only, indicated that the age and number of highways, and the number of ordinary roads, were uncorrelated with genetic differences (FST) among tree sparrows from different urban sites. Birds sampled at urban sites had similar levels of genetic diversity to those at rural sites. There was, however, evidence of some weak genetic structure between urban sites. Firstly, there were significant genetic differences (FST) between birds from opposite sides of the same highway, but no significant FST values between those from sites that were not separated by highways. Secondly, birds from eleven urban sites had loci that significantly deviated from the Hardy–Weinberg equilibrium but no such deviation was found in birds from rural sites. Conclusion We cannot, therefore, conclusively reject the hypothesis that highways have no effect on the gene flow of tree sparrow populations. Furthermore, since the significance of these results may increase with time, we suggested that research on the influence of highways on gene flow in urban bird populations needs to be conducted over several decades. PMID:24204724

  2. Power to detect trend in short-term time series of bird abundance

    USGS Publications Warehouse

    Thogmartin, W.E.; Gray, B.R.; Gallagher, M.; Young, N.; Rohweder, J.J.; Knutson, M.G.

    2007-01-01

    Avian point counts for population monitoring are often collected over a short timespan (e.g., 3-5 years). We examined whether power was adequate (power ???0.80) in short-duration studies to warrant the calculation of trend estimates. We modeled power to detect trends in abundance indices of eight bird species occurring across three floodplain habitats (wet prairie, early successional forest, and mature forest) as a function of trend magnitude, sample size, and species-specific sampling and among-year variance components. Point counts (5 min) were collected from 365 locations distributed among 10 study sites along the lower Missouri River; counts were collected over the period 2002 to 2004. For all study species, power appeared adequate to detect trends in studies of short duration (three years) at a single site when exponential declines were relatively large in magnitude (more than -5% year-1) and the sample of point counts per year was ???30. Efforts to monitor avian trends with point counts in small managed lands (i.e., refuges and parks) should recognize this sample size restriction by including point counts from offsite locations as a means of obtaining sufficient numbers of samples per strata. Trends of less than -5% year-1 are not likely to be consistently detected for most species over the short term, but short-term monitoring may still be useful as the basis for comparisons with future surveys. ?? The Cooper Ornithological Society 2007.

  3. Measuring Global Trends in the Status of Biodiversity: Red List Indices for Birds

    PubMed Central

    2004-01-01

    The rapid destruction of the planet's biodiversity has prompted the nations of the world to set a target of achieving a significant reduction in the rate of loss of biodiversity by 2010. However, we do not yet have an adequate way of monitoring progress towards achieving this target. Here we present a method for producing indices based on the IUCN Red List to chart the overall threat status (projected relative extinction risk) of all the world's bird species from 1988 to 2004. Red List Indices (RLIs) are based on the number of species in each Red List category, and on the number changing categories between assessments as a result of genuine improvement or deterioration in status. The RLI for all bird species shows that their overall threat status has continued to deteriorate since 1988. Disaggregated indices show that deteriorations have occurred worldwide and in all major ecosystems, but with particularly steep declines in the indices for Indo-Malayan birds (driven by intensifying deforestation of the Sundaic lowlands) and for albatrosses and petrels (driven by incidental mortality in commercial longline fisheries). RLIs complement indicators based on species population trends and habitat extent for quantifying global trends in the status of biodiversity. Their main weaknesses are that the resolution of status changes is fairly coarse and that delays may occur before some status changes are detected. Their greatest strength is that they are based on information from nearly all species in a taxonomic group worldwide, rather than a potentially biased subset. At present, suitable data are only available for birds, but indices for other taxonomic groups are in development, as is a sampled index based on a stratified sample from all major taxonomic groups. PMID:15510230

  4. Populations of migratory bird species that did not show a phenological response to climate change are declining.

    PubMed

    Møller, Anders Pape; Rubolini, Diego; Lehikoinen, Esa

    2008-10-21

    Recent rapid climatic changes are associated with dramatic changes in phenology of plants and animals, with optimal timing of reproduction advancing considerably in the northern hemisphere. However, some species may not have advanced their timing of breeding sufficiently to continue reproducing optimally relative to the occurrence of peak food availability, thus becoming mismatched compared with their food sources. The degree of mismatch may differ among species, and species with greater mismatch may be characterized by declining populations. Here we relate changes in spring migration timing by 100 European bird species since 1960, considered as an index of the phenological response of bird species to recent climate change, to their population trends. Species that declined in the period 1990-2000 did not advance their spring migration, whereas those with stable or increasing populations advanced their migration considerably. On the other hand, population trends during 1970-1990 were predicted by breeding habitat type, northernmost breeding latitude, and winter range (with species of agricultural habitat, breeding at northern latitudes, and wintering in Africa showing an unfavorable conservation status), but not by change in migration timing. The association between population trend in 1990-2000 and change in migration phenology was not confounded by any of the previously identified predictors of population trends in birds, or by similarity in phenotype among taxa due to common descent. Our findings imply that ecological factors affecting population trends can change over time and suggest that ongoing climatic changes will increasingly threaten vulnerable migratory bird species, augmenting their extinction risk. PMID:18849475

  5. Population Trends and the Status of Population Policy in Africa.

    ERIC Educational Resources Information Center

    Rogge, John R.

    1982-01-01

    The major trend towards worldwide easing of the birthrate does not include the current population patterns in Africa. The population policies of African nations range along a continuum from totally pronatal to strongly antinatal. However, even antinatal policies have had little effect on the overall spiralling upward population trend. (JA)

  6. Seasonal distribution of bird populations at the Patuxent Research Refuge

    USGS Publications Warehouse

    Stewart, R.E.; Cope, J.B.; Robbins, C.S.; Brainerd, J.W.

    2000-01-01

    A detailed study of seasonal changes in bird populationswas made at the Patuxent Research Refuge, located between Bowie and Laurel, Maryland during the years 1936-1949. The history of the Refuge is reviewed and its physical and biological characteristlcs summarized.. The methods of study used during the investigation mcluded: periodic censuses of a representative 304-acre study area over a two-year period; a census of the breeding population of the entire. Refuge during one year; detailed population studies of representative habitats during the breeding season; censuses of the wintering population of. the entire Refuge during two years; general surveys of wintering populations for seven years; and general observations of seasonal changes in bird populatlons over a fourteen-year period, including data from an extensive banding program and from many special types of censuses. The phenology of the Refuge is described in conslderable detail throughout the year, with special attention given to major fluctuatIons in bIrd populations as correlated with climatic changes and with seasonal aspectlon. of the vegetation. The component specIes of birds m the more important migration waves are listed. Figures approximating the Refuge breeding and wmtering populations are given, while indices representing the relative abundance of bird populations, based on figures from the two-year seasonal populatlon study, were obtained for the entire year. The greatest variety of species as well as the greatest number of individuals occurred on the Refuge during the migration .periods in spring and fall, the variety of species being slightly higher in spring than in fa!l, while the population of individuals was considerably higher in fall. Wmtering and breeding populations were low and relatively stable compared to the populations at other seasons.The ecological affinities of the bird populations differed greatly from one season to another. Species characteristic of edge habitats were much

  7. Temporal Variation in Population Size of European Bird Species: Effects of Latitude and Marginality of Distribution

    PubMed Central

    Cuervo, José J.; Møller, Anders P.

    2013-01-01

    In the Northern Hemisphere, global warming has been shown to affect animal populations in different ways, with southern populations in general suffering more from increased temperatures than northern populations of the same species. However, southern populations are also often marginal populations relative to the entire breeding range, and marginality may also have negative effects on populations. To disentangle the effects of latitude (possibly due to global warming) and marginality on temporal variation in population size, we investigated European breeding bird species across a latitudinal gradient. Population size estimates were regressed on years, and from these regressions we obtained the slope (a proxy for population trend) and the standard error of the estimate (SEE) (a proxy for population fluctuations). The possible relationships between marginality or latitude on one hand and slopes or SEE on the other were tested among populations within species. Potentially confounding factors such as census method, sampling effort, density-dependence, habitat fragmentation and number of sampling years were controlled statistically. Population latitude was positively related to regression slopes independent of marginality, with more positive slopes (i.e., trends) in northern than in southern populations. The degree of marginality was positively related to SEE independent of latitude, with marginal populations showing larger SEE (i.e., fluctuations) than central ones. Regression slopes were also significantly related to our estimate of density-dependence and SEE was significantly affected by the census method. These results are consistent with a scenario in which southern and northern populations of European bird species are negatively affected by marginality, with southern populations benefitting less from global warming than northern populations, thus potentially making southern populations more vulnerable to extinction. PMID:24147048

  8. America's Changing Population: Demographic Trends.

    ERIC Educational Resources Information Center

    Morrison, Peter A.

    1981-01-01

    Surveys the importance of migration trends in the United States away from the Northeastern urban areas into the sunbelt states of the West and Southwest. Emphasis is placed on ways in which this demographic transformation disturbs social, economic, and political arrangements. (DB)

  9. Overview of national bird population monitoring programs and databases

    USGS Publications Warehouse

    Butcher, G.S.; Peterjohn, B.; Ralph, C.J.

    1993-01-01

    A number of programs have been set up to monitor populations of nongame migratory birds. We review these programs and their purposes and provide information on obtaining data or results from these programs. In addition, we review recommendations for improving these programs.

  10. [Population policies and population trends in China].

    PubMed

    Pressat, R

    1983-04-01

    Although relatively little has been known about the Chinese population in recent centuries, figures are available for more remote times. In the year 2 the Chinese population was recorded at 60 million. In 1928, when the last pre-Revolution census was conducted, China had a population of 475 million. The population was not believed to have grown very much due to internal disorders, war, and foreigh invasion, but the 1953 census counted 582 million to which were added 18 million to include Taiwan and overseas Chinese. The figure of 600 million appears to mark the beginning of concern over demographic problems. The crude birth rate was estimated at 37/1000 and the death rate at 17/1000. The 1953 census was conducted with Soviet aid and was given some publicity. The period 1953-58 was marked by a mortality decline and a steady fertility rate, but the population is believed to have declined from 647 million in 1958 to 643 million in 1962, the end of the Great Leap Forward. A census suppressed until recently gave a total of 694 million for 1964. Population growth was considerable from 1961-66. In the 1st part of the Cultural Revolution from 1966-70, no effort was made to control population growth; in 1971, the crude birth rate was estimated at 30-35/1000, the mortality rate was 8/1000, and the growth rate was 2.6%. 1971-79 marked the 1st phase of birth limitation, which became more pressing with time. The population was counted at 1 billion 8 million in 1982, with a birth rate of 21/1000, a death rate of 6/1000, and a growth rate of 1.5%. Because of China's comprehensive system of population registration, the results of the 1982 census were not completely unexpected. Wide differences in growth rates were noted between provinces, and the minorities grew at a faster rate than the Han majority. Immediately after the Revolution, population was relatively neglected in China in favor of greater attention to economic growth. The 1st warnings about the consequences of overly

  11. Wildlife population trends in protected areas predicted by national socio-economic metrics and body size.

    PubMed

    Barnes, Megan D; Craigie, Ian D; Harrison, Luke B; Geldmann, Jonas; Collen, Ben; Whitmee, Sarah; Balmford, Andrew; Burgess, Neil D; Brooks, Thomas; Hockings, Marc; Woodley, Stephen

    2016-01-01

    Ensuring that protected areas (PAs) maintain the biodiversity within their boundaries is fundamental in achieving global conservation goals. Despite this objective, wildlife abundance changes in PAs are patchily documented and poorly understood. Here, we use linear mixed effect models to explore correlates of population change in 1,902 populations of birds and mammals from 447 PAs globally. On an average, we find PAs are maintaining populations of monitored birds and mammals within their boundaries. Wildlife population trends are more positive in PAs located in countries with higher development scores, and for larger-bodied species. These results suggest that active management can consistently overcome disadvantages of lower reproductive rates and more severe threats experienced by larger species of birds and mammals. The link between wildlife trends and national development shows that the social and economic conditions supporting PAs are critical for the successful maintenance of their wildlife populations. PMID:27582180

  12. Climate Change Influences on Antarctic Bird Populations

    NASA Astrophysics Data System (ADS)

    Korczak-Abshire, Małgorzata

    2010-01-01

    Rapid changes in the major environmental variables like: temperature, wind and precipitation have occurred in the Antarctic region during the last 50 years. In this very sensitive region, even small changes can potentially lead to major environmental perturbations. Then the climate change poses a new challenge to the survival of Antarctic wildlife. As important bioindicators of changes in the ecosystem seabirds and their response to the climate perturbations have been recorded. Atmospheric warming and consequent changes in sea ice conditions have been hypothesized to differentially affect predator populations due to different predator life-history strategies and substantially altered krill recruitment dynamics.

  13. Flood trends and population dynamics

    NASA Astrophysics Data System (ADS)

    Di Baldassarre, G.

    2012-04-01

    Since the earliest recorded civilizations, such as those in Mesopotamia and Egypt that developed in the fertile floodplains of the Tigris and Euphrates and Nile rivers, humans tend to settle in flood prone areas as they offer favorable conditions for economic development. However, floodplains are also exposed to flood disasters that might cause severe socio-economic and environmental damages not to mention losses of human lives. A flood event turns to be a disaster when it coincides with a vulnerable environment exceeding society's capacity to manage the adverse consequences. This presentation discusses the link between hydrological risk and population change by referring to the outcomes of scientific works recently carried out in Africa and Europe. More specifically, it is shown that the severity of flood disasters, currently affecting more than 100 million people a year, might be seriously exacerbated because of population change. In fact, flood exposure and/or vulnerability might increase because of rapid population growth (and its spatial and temporal dynamics, e.g. urbanization) in the African continent and because of population ageing in many European countries. Lastly, timely and economically sustainable actions to mitigate this increasing hydrological risk are critically evaluated.

  14. Demographic routes to variability and regulation in bird populations.

    PubMed

    Sæther, Bernt-Erik; Grøtan, Vidar; Engen, Steinar; Coulson, Tim; Grant, Peter R; Visser, Marcel E; Brommer, Jon E; Rosemary Grant, B; Gustafsson, Lars; Hatchwell, Ben J; Jerstad, Kurt; Karell, Patrik; Pietiäinen, Hannu; Roulin, Alexandre; Røstad, Ole W; Weimerskirch, Henri

    2016-01-01

    There is large interspecific variation in the magnitude of population fluctuations, even among closely related species. The factors generating this variation are not well understood, primarily because of the challenges of separating the relative impact of variation in population size from fluctuations in the environment. Here, we show using demographic data from 13 bird populations that magnitudes of fluctuations in population size are mainly driven by stochastic fluctuations in the environment. Regulation towards an equilibrium population size occurs through density-dependent mortality. At small population sizes, population dynamics are primarily driven by environment-driven variation in recruitment, whereas close to the carrying capacity K, variation in population growth is more strongly influenced by density-dependent mortality of both juveniles and adults. Our results provide evidence for the hypothesis proposed by Lack that population fluctuations in birds arise from temporal variation in the difference between density-independent recruitment and density-dependent mortality during the non-breeding season. PMID:27328710

  15. Demographic routes to variability and regulation in bird populations

    PubMed Central

    Sæther, Bernt-Erik; Grøtan, Vidar; Engen, Steinar; Coulson, Tim; Grant, Peter R.; Visser, Marcel E.; Brommer, Jon E.; Rosemary Grant, B.; Gustafsson, Lars; Hatchwell, Ben J.; Jerstad, Kurt; Karell, Patrik; Pietiäinen, Hannu; Roulin, Alexandre; Røstad, Ole W.; Weimerskirch, Henri

    2016-01-01

    There is large interspecific variation in the magnitude of population fluctuations, even among closely related species. The factors generating this variation are not well understood, primarily because of the challenges of separating the relative impact of variation in population size from fluctuations in the environment. Here, we show using demographic data from 13 bird populations that magnitudes of fluctuations in population size are mainly driven by stochastic fluctuations in the environment. Regulation towards an equilibrium population size occurs through density-dependent mortality. At small population sizes, population dynamics are primarily driven by environment-driven variation in recruitment, whereas close to the carrying capacity K, variation in population growth is more strongly influenced by density-dependent mortality of both juveniles and adults. Our results provide evidence for the hypothesis proposed by Lack that population fluctuations in birds arise from temporal variation in the difference between density-independent recruitment and density-dependent mortality during the non-breeding season. PMID:27328710

  16. Geographic patterns in population trends of neotropical migrants in North America

    USGS Publications Warehouse

    Sauer, J.R.; Droege, S.

    1992-01-01

    We use the route-regression method to estimate the population trends of 100 species of Neotropical migrants using data from the North American Breeding Bird Survey (BBS). We examine long-term (1966-1988) and recent (1978-1988) trends. In the long-term, more species of Neotropical migrants were increasing than were decreasing in the eastern and western parts of the continent, but recent trends indicate that more species decreased than increased in their population index in the east. Recent population declines in the eastern part of the continent were primarily associated with bird species that breed in forested habitat. No association was detected between changes in forest acreages by state and population trends of Neotropical migrants in the United States and Canada.

  17. Appendix A: other methods for estimating trends of Arctic birds

    USGS Publications Warehouse

    Bart, Jonathan; Brown, Stephen; Morrison, R.I. Guy; Smith, Paul A.

    2012-01-01

    The Arctic PRISM was designed to determine shorebird population size and trend. During an extensive peer review of PRISM, some reviewers suggested that measuring demographic rates or monitoring shorebirds on migration would be more appropriate than estimating population size on the breeding grounds. However, each method has its own limitations. For demographic monitoring, an unbiased estimate based on a large sample of first-year survivorship would be extremely difficult for shorebirds in the arctic because the needed sample size would be unobtainable (in Canada at least) and the level of effort that would need to be expended (both financial and human resource-wise) would far exceed that of the current Arctic PRISM methodology. For migration monitoring, issues such as changes in use of monitored to non-monitored sites, residency times, and detection rates introduce bias that has not yet been resolved. While we believe demographic and migration monitoring are very valuable and are already components of the PRISM approach (e.g., Tier 2 sites focus on the collection of demographic data), we do not believe that either is likely to achieve the PRISM accuracy target of an 80% power to detect a 50% decline.

  18. Estimating population trends with a linear model: technical comments

    USGS Publications Warehouse

    Sauer, J.R.; Link, W.A.; Royle, J. Andrew

    2004-01-01

    Controversy has sometimes arisen over whether there is a need to accommodate the limitations of survey design in estimating population change from the count data collected in bird surveys. Analyses of surveys such as the North American Breeding Bird Survey (BBS) can be quite complex; it is natural to ask if the complexity is necessary, or whether the statisticians have run amok. Bart et al. (2003) propose a very simple analysis involving nothing more complicated than simple linear regression, and contrast their approach with model-based procedures. We review the assumptions implicit to their proposed method, and document that these assumptions are unlikely to be valid for surveys such as the BBS. One fundamental limitation of a purely design-based approach is the absence of controls for factors that influence detection of birds at survey sites. We show that failure to model observer effects in survey data leads to substantial bias in estimation of population trends from BBS data for the 20 species that Bart et al. (2003) used as the basis of their simulations. Finally, we note that the simulations presented in Bart et al. (2003) do not provide a useful evaluation of their proposed method, nor do they provide a valid comparison to the estimating- equations alternative they consider.

  19. Loss of sagebrush ecosystems and declining bird populations in the Intermountain West: Priority research issues and information needs

    USGS Publications Warehouse

    U.S. Geological Survey

    2002-01-01

    Sagebrush lands in the Intermountain West are declining rapidly in quality and extent. Consequently, populations of many bird species dependent on these ecosystems also are declining. The greater sage-grouse has been petitioned for listing as a threatened and endangered species, and other species of sagebrush-obligate birds have special conservation status in most states. We identified the primary issues and information needs during a multi-agency workshop, conducted in response to concerns by management agencies related to declining bird population trends in sagebrush habitats. Priority needs were to (1) obtain a better understanding of bird response to habitat and landscape features, (2) develop monitoring designs to sample habitats and bird populations, (3) determine the effects of land use on sagebrush habitats and dependent bird species, and (4) identify linkages between breeding and wintering ranges. This agenda will identify causes and mechanisms of population declines in birds dependent on sagebrush ecosystems and will lead to better management of the ecosystems upon which they depend.

  20. Population models for passerine birds: structure, parameterization, and analysis

    USGS Publications Warehouse

    Noon, B.R.; Sauer, J.R.

    1992-01-01

    Population models have great potential as management tools, as they use infonnation about the life history of a species to summarize estimates of fecundity and survival into a description of population change. Models provide a framework for projecting future populations, determining the effects of management decisions on future population dynamics, evaluating extinction probabilities, and addressing a variety of questions of ecological and evolutionary interest. Even when insufficient information exists to allow complete identification of the model, the modelling procedure is useful because it forces the investigator to consider the life history of the species when determining what parameters should be estimated from field studies and provides a context for evaluating the relative importance of demographic parameters. Models have been little used in the study of the population dynamics of passerine birds because of: (1) widespread misunderstandings of the model structures and parameterizations, (2) a lack of knowledge of life histories of many species, (3) difficulties in obtaining statistically reliable estimates of demographic parameters for most passerine species, and (4) confusion about functional relationships among demographic parameters. As a result, studies of passerine demography are often designed inappropriately and fail to provide essential data. We review appropriate models for passerine bird populations and illustrate their possible uses in evaluating the effects of management or other environmental influences on population dynamics. We identify environmental influences on population dynamics. We identify parameters that must be estimated from field data, briefly review existing statistical methods for obtaining valid estimates, and evaluate the present status of knowledge of these parameters.

  1. Forest management under uncertainty for multiple bird population objectives

    USGS Publications Warehouse

    Moore, C.T.; Plummer, W.T.; Conroy, M.J.

    2005-01-01

    We advocate adaptive programs of decision making and monitoring for the management of forest birds when responses by populations to management, and particularly management trade-offs among populations, are uncertain. Models are necessary components of adaptive management. Under this approach, uncertainty about the behavior of a managed system is explicitly captured in a set of alternative models. The models generate testable predictions about the response of populations to management, and monitoring data provide the basis for assessing these predictions and informing future management decisions. To illustrate these principles, we examine forest management at the Piedmont National Wildlife Refuge, where management attention is focused on the recovery of the Red-cockaded Woodpecker (Picoides borealis) population. However, managers are also sensitive to the habitat needs of many non-target organisms, including Wood Thrushes (Hylocichla mustelina) and other forest interior Neotropical migratory birds. By simulating several management policies on a set of-alternative forest and bird models, we found a decision policy that maximized a composite response by woodpeckers and Wood Thrushes despite our complete uncertainty regarding system behavior. Furthermore, we used monitoring data to update our measure of belief in each alternative model following one cycle of forest management. This reduction of uncertainty translates into a reallocation of model influence on the choice of optimal decision action at the next decision opportunity.

  2. [Population trends in Andorra and Monaco].

    PubMed

    Lluelles, M J; Sanguin A-l

    1995-01-01

    Population trends in the micro-states of Andorra and Monaco are described and compared. The authors note that the population of Andorra has increased twelvefold since 1947 due to the development of a tax-free economy and a winter sports industry, whereas Monaco, on a much smaller territorial space, has remained relatively demographically stable. PMID:12156750

  3. Consistent response of bird populations to climate change on two continents.

    PubMed

    Stephens, Philip A; Mason, Lucy R; Green, Rhys E; Gregory, Richard D; Sauer, John R; Alison, Jamie; Aunins, Ainars; Brotons, Lluís; Butchart, Stuart H M; Campedelli, Tommaso; Chodkiewicz, Tomasz; Chylarecki, Przemysław; Crowe, Olivia; Elts, Jaanus; Escandell, Virginia; Foppen, Ruud P B; Heldbjerg, Henning; Herrando, Sergi; Husby, Magne; Jiguet, Frédéric; Lehikoinen, Aleksi; Lindström, Åke; Noble, David G; Paquet, Jean-Yves; Reif, Jiri; Sattler, Thomas; Szép, Tibor; Teufelbauer, Norbert; Trautmann, Sven; van Strien, Arco J; van Turnhout, Chris A M; Vorisek, Petr; Willis, Stephen G

    2016-04-01

    Global climate change is a major threat to biodiversity. Large-scale analyses have generally focused on the impacts of climate change on the geographic ranges of species and on phenology, the timing of ecological phenomena. We used long-term monitoring of the abundance of breeding birds across Europe and the United States to produce, for both regions, composite population indices for two groups of species: those for which climate suitability has been either improving or declining since 1980. The ratio of these composite indices, the climate impact indicator (CII), reflects the divergent fates of species favored or disadvantaged by climate change. The trend in CII is positive and similar in the two regions. On both continents, interspecific and spatial variation in population abundance trends are well predicted by climate suitability trends. PMID:27034371

  4. Consistent response of bird populations to climate change on two continents

    USGS Publications Warehouse

    Stephens, Philip A.; Mason, Lucy R.; Green, Rhys E.; Gregory, Richard D.; Sauer, John R.; Alison, Jamie; Aunins, Ainars; Brotons, Lluís; Butchart, Stuart H.M.; Campedelli, Tommaso; Chodkiewicz, Tomasz; Chylarecki, Przemyslaw; Crowe, Olivia; Elts, Jaanus; Escandell, Virginia; Foppen, Ruud P.B.; Heldbjerg, Henning; Herrando, Sergi; Husby, Magne; Jiguet, Frédéric; Lehikoinen, Aleksi; Lindström, Åke; Noble, David G.; Paquet, Jean-Yves; Reif, Jiri; Sattler, Thomas; Szép, Tibor; Teufelbauer, Norbert; Trautmann, Sven; Van Strien, Arco; van Turnhout, Chris A.M.; Vorisek, Petr; Willis, Stephen G.

    2016-01-01

    Global climate change is a major threat to biodiversity. Large-scale analyses have generally focused on the impacts of climate change on the geographic ranges of species and on phenology, the timing of ecological phenomena. We used long-term monitoring of the abundance of breeding birds across Europe and the United States to produce, for both regions, composite population indices for two groups of species: those for which climate suitability has been either improving or declining since 1980. The ratio of these composite indices, the climate impact indicator (CII), reflects the divergent fates of species favored or disadvantaged by climate change. The trend in CII is positive and similar in the two regions. On both continents, interspecific and spatial variation in population abundance trends are well predicted by climate suitability trends.

  5. Forest Bird Distribution, Density and Trends in the Ka'u Region of Hawai'i Island

    USGS Publications Warehouse

    Gorresen, P. Marcos; Camp, Richard J.; Pratt, Thane K.

    2007-01-01

    An accurate and current measure of population status and trend is necessary for conservation and management efforts. Scott and Kepler (1985) provided a comprehensive review of the status of native Hawaiian birds based on the extensive Hawaii Forest Bird Survey (HFBS) of the main islands (Scott et al. 1986). At that time, they documented declining populations and decreasing ranges for most species, and the extinction of several species over the previous 50 years. Many native bird species continue to decline throughout Hawai`i (Camp et al. In review, Gorresen et al. In prep.). The focus of this study is the mid-to-high elevation rainforest on the southeast windward slopes of Mauna Loa Volcano (Figure 1). Known as Ka`u, the region encompasses forest lands protected by Kamehameha Schools, The Nature Conservancy, Hawai`i Volcanoes National Park (HVNP), and the State of Hawai'i's Ka`u Forest Reserve, Kapapala Forest Reserve and Kapapala Cooperative Game Management Area,. Together these lands support one of three main concentrations of native forest birds on the Hawai`i Island (the other two being centered on the Hakalau Forest National Wildlife Refuge and Kulani-Keauhou area in the north and central windward part of the island, respectively.) Because this region harbors important populations of native and endangered forest birds in some of the best remaining forest habitat on the island, it has been a focus of forest bird surveys since the 1970s. The Ka`u region was first quantitatively surveyed in 1976 by the Hawaii Forest Bird Survey (Scott et al. 1986). Surveys were conducted by State of Hawai`i Division of Forestry and Wildlife in 1993 and 2002 and by the U.S. National Park Service and the U.S. Geological Survey in 2004 and 2005. In this report, we present analyses of the density, distribution and trends of native and introduced forest bird within the Ka`u region of Hawai`i Island. The analyses cover only those species with sufficient detections to model detection

  6. Recovery Trends in Marine Mammal Populations

    PubMed Central

    Magera, Anna M.; Mills Flemming, Joanna E.; Kaschner, Kristin; Christensen, Line B.; Lotze, Heike K.

    2013-01-01

    Marine mammals have greatly benefitted from a shift from resource exploitation towards conservation. Often lauded as symbols of conservation success, some marine mammal populations have shown remarkable recoveries after severe depletions. Others have remained at low abundance levels, continued to decline, or become extinct or extirpated. Here we provide a quantitative assessment of (1) publicly available population-level abundance data for marine mammals worldwide, (2) abundance trends and recovery status, and (3) historic population decline and recent recovery. We compiled 182 population abundance time series for 47 species and identified major data gaps. In order to compare across the largest possible set of time series with varying data quality, quantity and frequency, we considered an increase in population abundance as evidence of recovery. Using robust log-linear regression over three generations, we were able to classify abundance trends for 92 spatially non-overlapping populations as Significantly Increasing (42%), Significantly Decreasing (10%), Non-Significant Change (28%) and Unknown (20%). Our results were comparable to IUCN classifications for equivalent species. Among different groupings, pinnipeds and other marine mammals (sirenians, polar bears and otters) showed the highest proportion of recovering populations, likely benefiting from relatively fast life histories and nearshore habitats that provided visibility and protective management measures. Recovery was less frequent among cetaceans, but more common in coastal than offshore populations. For marine mammals with available historical abundance estimates (n = 47), larger historical population declines were associated with low or variable recent recoveries so far. Overall, our results show that many formerly depleted marine mammal populations are recovering. However, data-deficient populations and those with decreasing and non-significant trends require attention. In particular, increased

  7. Status and trends of the land bird avifauna on Tinian and Aguiguan, Mariana Islands.

    USGS Publications Warehouse

    Camp, Richard J.; Pratt, Thane K.; Amidon, Fred; Marshall, Ann P.; Kremer, Shelly; Laut, Megan

    2012-01-01

    Avian surveys were conducted on the islands of Tinian and Aguiguan, Marianas Islands, in 2008 by the U.S. Fish and Wildlife Service to provide current baseline densities and abundances and assess population trends using data collected from previous surveys. On Tinian, during the three surveys (1982, 1996, and 2008), 18 species were detected, and abundances and trends were assessed for 12 species. Half of the 10 native species—Yellow Bittern (Ixobrychus sinensis), White-throated Ground-Dove (Gallicolumba xanthonura), Collared Kingfisher (Todiramphus chloris), Rufous Fantail (Rhipidura rufifrons), and Micronesian Starling (Aplonis opaca)—and one alien bird—Island Collared-Dove (Streptopelia bitorquata)—have increased since 1982. Three native birds—Mariana Fruit-Dove (Ptilinopus roseicapilla), Micronesian Honeyeater (Myzomela rubratra), and Tinian Monarch (Monarcha takatsukasae)—have decreased since 1982. Trends for the remaining two native birds—White Tern (Gygis alba) and Bridled White-eye (Zosterops saypani)—and one alien bird—Eurasian Tree Sparrow (Passer montanus)—were considered relatively stable. Only five birds—White-throated Ground-Dove, Mariana Fruit-Dove, Tinian Monarch, Rufous Fantail, and Bridled White-eye—showed significant differences among regions of Tinian by year. Tinian Monarch was found in all habitat types, with the greatest monarch densities observed in limestone forest, secondary forest, and tangantangan (Leucaena leucocephala) thicket and the smallest densities found in open fields and urban/residential habitats. On Aguiguan, 19 species were detected on one or both of the surveys (1982 and 2008), and abundance estimates were produced for nine native and one alien species. Densities for seven of the nine native birds—White-throated Ground-Dove, Mariana Fruit-Dove, Collared Kingfisher, Rufous Fantail, Bridled White-eye, Golden White-eye (Cleptornis marchei), and Micronesian Starling—and the alien bird— Island

  8. USING POPULATION MODELS TO EVALUATE RISK IN POPULATION OF BIRDS

    EPA Science Inventory

    Wildlife populations are exposed to varying habitat structure and quality, as well as an array of human-induced environmental stressors. Predicting the consequences to a real population of one perturbation (e.g. a pesticide application) without considering other human activities ...

  9. Noninvasive methods for monitoring bear population trends

    USGS Publications Warehouse

    Kendall, Katherine

    2010-01-01

    The U.S. Geological Survey began a grizzly bear research project in 2009 in the Northern Continental Divide Ecosystem (NCDE) of northwestern Montana. This work uses hair collection and DNA analysis methods similar to those used in the 2004 Northern Divide Grizzly Bear Project. However, instead of producing a snapshot of population size, the objectives of this new work are to estimate population growth rates by collecting hair at natural bear rubs along trails, roads, and fence and power lines. This approach holds promise of providing reliable estimates of population trends in an efficient, cost-effective, and unobtrusive way.

  10. Extinction risk to bird populations caused by DDT exposure.

    PubMed

    Nakamaru, Mayuko; Iwasa, Yoh; Nakanishi, Junko

    2003-10-01

    The impact of toxic chemicals on wild animals and plants can be quantified in terms of the enhanced risk of population extinction. To illustrate a method for doing this, we estimated such impact for two bird species: herring gull (Larus argentatus) in Long Island, NY, and sparrowhawk (Accipiter nisus) in eastern England, when they were exposed to DDT (p,p(')-dichlorodiphenyltrichloroethane) and its metabolites (called DDTs). The method we used is based on a formula of the mean time to population extinction derived for a stochastic differential equation (the canonical model). The intrinsic rate of natural population growth was estimated from an exponentially growing population, and the intensity of the environmental fluctuation was estimated from the magnitude of population size fluctuation. The effect of exposure to DDTs in reducing the population growth rate was evaluated based on an age-structured population model, by assuming that age-specific fertility is density-dependent and sensitive to DDTs exposure, but age-specific survivorship is not. The results are expressed in terms of the risk equivalent--the decrease in carrying capacity K that causes the same enhancement of extinction risk as chemical exposure at a given level. The risk equivalent can be used in mitigation banking. PMID:12946395

  11. Effects of DDT on bird population of scrub forest

    USGS Publications Warehouse

    Robbins, C.S.; Stewart, R.E.

    1949-01-01

    An oil spray of DDT was applied at the rate of five pounds per acre to a 90-acre tract of 5-year-old scrub and sapling growth at Beltsville, Maryland. Bird population studies were carried on in a 30-acre plot at the center of the sprayed area, and in a 30-acre check area of the same habitat one-half mile away. Of the five commonest species in the sprayed area, the Maryland yellowthroat, prairie warbler, and house wren were reduced 80 per cent, and the red-eyed towhee was apparently reduced 35 per cent; while no appreciable change in the numbers of yellow-breasted chats was noted. The total decrease for the five commonest species, which represented 77 per cent of the original population, was 65 per cent.

  12. Hatching failure increases with severity of population bottlenecks in birds

    PubMed Central

    Briskie, James V.; Mackintosh, Myles

    2004-01-01

    Severe bottlenecks can reduce genetic diversity and increase inbreeding as individuals are forced to mate with close relatives, but it is unknown at what minimum population size the negative fitness consequences of bottlenecks are expressed. The New Zealand avifauna contains a large number of species that have gone through bottlenecks of varying severity, providing an exceptional opportunity to test this question by using the comparative method. Using decreased hatchability as a measure of fitness costs, we found that hatching failure was significantly greater among both native and introduced species that had passed through bottlenecks of <150 individuals. Comparisons between pre- and postbottleneck populations of introduced species suggest that hatching problems arise even in populations founded by <600 individuals. Our study confirms that hatching failure is widespread and persistent among birds passing through severe bottlenecks and that the population sizes at which this fitness cost is expressed are several times greater than the number of individuals currently used to found most new populations of endangered species. We recommend that conservation managers revise the protocols they use for reintroductions or they may unwittingly reduce the long-term viability of the species they are trying to save. PMID:14699045

  13. Global population trends and policy options.

    PubMed

    Ezeh, Alex C; Bongaarts, John; Mberu, Blessing

    2012-07-14

    Rapid population growth is a threat to wellbeing in the poorest countries, whereas very low fertility increasingly threatens the future welfare of many developed countries. The mapping of global trends in population growth from 2005-10 shows four distinct patterns. Most of the poorest countries, especially in sub-Saharan Africa, are characterised by rapid growth of more than 2% per year. Moderate annual growth of 1-2% is concentrated in large countries, such as India and Indonesia, and across north Africa and western Latin America. Whereas most advanced-economy countries and large middle-income countries, such as China and Brazil, are characterised by low or no growth (0-1% per year), most of eastern Europe, Japan, and a few western European countries are characterised by population decline. Countries with rapid growth face adverse social, economic, and environmental pressures, whereas those with low or negative growth face rapid population ageing, unsustainable burdens on public pensions and health-care systems, and slow economic growth. Countries with rapid growth should consider the implementation of voluntary family planning programmes as their main policy option to reduce the high unmet need for contraception, unwanted pregnancies, and probirth reproductive norms. In countries with low or negative growth, policies to address ageing and very low fertility are still evolving. Further research into the potential effect of demographic policies on other social systems, social groups, and fertility decisions and trends is therefore recommended. PMID:22784532

  14. Recent Trends in Bird Abundance on Rhode Island Salt Marshes

    EPA Science Inventory

    Salt marsh habitat is under pressure from development on the landward side, and sea level rise from the seaward side. The resulting loss of habitat is potentially disastrous for salt marsh dependent species. To assess the population status of three species of salt marsh dependent...

  15. Uncommon breeding birds in North Dakota: Population estimates and frequencies of occurrence

    USGS Publications Warehouse

    Igl, L.D.; Johnson, D.H.; Kantrud, H.A.

    1999-01-01

    Breeding bird populations were surveyed on 128 randomly selected quarter-sections throughout North Dakota in 1967, 1992, and 1993. Population estimates and frequencies of occurrence are reported for 92 uncommon breeding bird species with statewide frequencies of less than 10%.

  16. Marine bird populations of Prince William Sound, Alaska, before and after the Exxon Valdez oil spill. Bird study number 2. Exxon Valdez oil spill state/federal natural resource damage assessment final report

    SciTech Connect

    Klosiewski, S.P.; Laing, K.K.

    1994-06-01

    We estimated the summer and winter abundance of marine birds in Prince William Sound, Alaska, following the 1989 Exxon Valdez oil spill, examined changes in population size between pre-spill and post-spill surveys, and compared pre- to post-oil spill population trends in the oiled zone of the Sound relative to trends in the unoiled zone. Ninety-nine species of birds were observed on surveys. Estimated populations of 15 to 32 species/species groups demonstrated declines over the 17-19 year period between pre- and post-spill surveys. However, because of the long time period between surveys, we could not directly associate overall population declines with the oil spill.

  17. Effects of habitat change along Breeding Bird Survey routes in the central Appalachians on Cerulean Warbler population

    USGS Publications Warehouse

    McElhone, P.; Wood, P.W.; Dawson, D.

    2007-01-01

    The cerulean warbler (Dendroica cerulea) is one of the highest priority bird species in the eastern United States because populations have declined 4.3% annually during 1966?2005 based on Breeding Bird Survey (BBS) data. Habitat loss and fragmentation due to land use changes is thought to be one of the major factors contributing to the decline. BBS routes, the primary source for monitoring bird population trends, include 50 sampling stops every 0.8 km. Although data from BBS routes are extrapolated to determine regional trends in bird populations, it is important to understand the effects of habitat changes at the stop-level along BBS routes. Route-level analysis of habitat changes may mask important changes that are occurring at a smaller scale particularly for the cerulean warbler which displays several micro-scale habitat preferences. We are examining cerulean warbler habitat and population changes in its core breeding range of the Ohio Hills and Cumberland Plateau physiographic regions. We quantified land cover changes within 300 m of BBS routes in the core cerulean warbler breeding range of Ohio, West Virginia, and Kentucky by digitizing aerial photographs from two time periods: the 1980s and 2004. We also quantified land cover changes within 300 m of BBS routes with the National Land Cover Dataset (NLCD) from 1992 and 2001. The hand-digitized aerial photos will be compared with the NLCD to determine how similar the two methods are in quantifying land cover changes. We then compared stop-level land cover changes with stop level changes in cerulean warbler detections within the same time periods along the BBS routes. This will allow for a more detailed analysis of how well habitat changes along BBS routes reflect the changes in cerulean warbler populations.

  18. Painted Bunting Breeding Bird Survey trends associated with landscape changes in Georgia and South Carolina

    USGS Publications Warehouse

    Meyers, J.M.

    2000-01-01

    Landscape changes during the first 3 decades of the Breeding Bird Survey (BBS) may account for the Painted Bunting's declining population trend. In the southeastern U.S., it is estimated that this bunting has declined 3.5 % per year since 1966. I collected landscape data centered on identical 5-stop areas (n = 33, 306 ha each) of the BBS during early (1960s - 1970s) and late decades (1980s - 1990s). Peak 30-yr counts for Painted Buntings were found at the center of the 5-stop areas. I used stepwise multiple regression analysis to model the mean number of Painted Buntings (in the area during 3 yr, dependent variable) associated with landscape metrics (independent variables). During the early decades the average amount of edge on developed land (p = 0.10), average patch size of agriculture land (p = 0.01), average size of shrub-scrub and young forest (p = 0.09), and average amount of edge for emergent wetlands (p = 0.03) explained 40% of the variation in Painted Buntings counts. In the late decades average amount of edge on developed land (p = 0.04) and average amount of edge on emergent wetlands (p = 0.005) explained 35% of the variation in Painted Bunting counts. Large losses of agricultural land (proportion = 0.177 to 0.094), which was developed or converted to intensively managed pin plantations, may have reduced potential bunting breeding habitat. Shrub-scrub and young forest habitat was constant (proportion = 0.136 to 0.134) but did not affect mean counts of buntings in the late decades. Protected emergent wetlands remained constnat also from the early to late decades (proportion = 0.056 to 0.06) and may provide habitat to maintain a smaller Painted Bunting population. At this time, it's unclear how develped land, which is increasing (proportion = 0.036 to 0.088), may be affecting the Painted Bunting population in GS and SC.

  19. Some consequences of using counts of birds banded as indices to populations

    USGS Publications Warehouse

    Sauer, J.R.; Link, W.A.

    2004-01-01

    In mist-net studies, it is often difficult to use capture-recapture methods to estimate number of birds present. Many investigators use number of birds captured as an index of population size. We investigate the consequences of using indices of bird abundance as surrogates for population size in hypothesis tests. Unless all of the birds present are captured, indices are biased estimates of local population size, and the amount of bias depends on the proportion of birds captured. We demonstrate the potential effects of bias on hypothesis tests based on indices. The bias generally causes type I error rates to be inflated. Investigators should either estimate the proportion of animals captured using capture-recapture methods or demonstrate that results of hypothesis tests based on indices are not consequences of bias in the indices.

  20. Regional Distribution Shifts Help Explain Local Changes in Wintering Raptor Abundance: Implications for Interpreting Population Trends

    PubMed Central

    Paprocki, Neil; Heath, Julie A.; Novak, Stephen J.

    2014-01-01

    Studies of multiple taxa across broad-scales suggest that species distributions are shifting poleward in response to global climate change. Recognizing the influence of distribution shifts on population indices will be an important part of interpreting trends within management units because current practice often assumes that changes in local populations reflect local habitat conditions. However, the individual- and population-level processes that drive distribution shifts may occur across a large, regional scale and have little to do with the habitats within the management unit. We examined the latitudinal center of abundance for the winter distributions of six western North America raptor species using Christmas Bird Counts from 1975–2011. Also, we considered whether population indices within western North America Bird Conservation Regions (BCRs) were explained by distribution shifts. All six raptors had significant poleward shifts in their wintering distributions over time. Rough-legged Hawks (Buteo lagopus) and Golden Eagles (Aquila chrysaetos) showed the fastest rate of change, with 8.41 km yr−1 and 7.74 km yr−1 shifts, respectively. Raptors may be particularly responsive to warming winters because of variable migration tendencies, intraspecific competition for nesting sites that drives males to winter farther north, or both. Overall, 40% of BCR population trend models were improved by incorporating information about wintering distributions; however, support for the effect of distribution on BCR indices varied by species with Rough-legged Hawks showing the most evidence. These results emphasize the importance of understanding how regional distribution shifts influence local-scale population indices. If global climate change is altering distribution patterns, then trends within some management units may not reflect changes in local habitat conditions. The methods used to monitor and manage bird populations within local BCRs will fundamentally change as

  1. Latent population responses of summer birds to a catastrophic, climatological event

    USGS Publications Warehouse

    Knopf, Fritz L.; Sedgwick, James A.

    1987-01-01

    Catastrophic events can create ecological crunches for avian populations. Ornithologists generally assume that such events elicit immediate, dramatic declines in populations followed by rapid recolonization of a site with habitat recovery. Despite total inundation of habitats within the South Platte floodplain of eastern Colorado during the 1983 breeding season, populations of Brown Thrashers (Toxostoma rufum) and Rufoussided Towhees (Pipilo erythrophthalmus) did not decline significantly from 1982 densities. However, populations of both species declined significantly in 1984 and towhee populations remained low in 1985. These observations support speculations from recent studies of shrubsteppe bird populations that site tenacity may play a stronger role in determining annual densities of breeding birds than previously realized.

  2. Estimating regional landbird populations from enhanced North American Breeding Bird Surveys

    USGS Publications Warehouse

    Twedt, Daniel J.

    2015-01-01

    Estimating the size of bird populations is central to effective conservation planning and prudent management. I updated estimated regional bird populations for the East Gulf Coastal Plain of Mississippi using data from 275 North American Breeding Bird Surveys from 2009 to 2013. However, regional bird populations estimated from count surveys of breeding birds may be biased due to lack of empirical knowledge of the distance at which a species is effectively detected and the probability of detecting a species if it is present. I used data recorded within two distance classes (0–50 m and >50–400 m) and three 1-min time intervals on 130 Breeding Bird Surveys to estimate detection probability and effective detection distance for 77 species. Incorporating these empirical estimates of detection probability and detection distance resulted in estimated regional populations for these species that were markedly greater than regional populations estimated without species-specific estimates of detection parameters. Using the same Breeding Bird Survey data, I also estimated probability of site occupancy for 66 species and extrapolated this to the proportion of area occupied in the East Gulf Coastal Plain of Mississippi. I combined the area occupied with the reported range of breeding territory size for 54 species to obtain independent estimates of regional bird populations. Although the true population of these species is unknown, estimated populations that incorporated empirical estimates of detection probability and detection distance were more likely to be within the range of independently estimated, occupancy-based, regional population estimates than were population estimates that lacked empirical detection and distance information.

  3. Women, population and development trends since 1984.

    PubMed

    Ware, H

    1989-01-01

    This paper review progress over the past 5 years with respect to the 6 recommendations adopted at the International Conference on Population 1984, which specifically address the situation of women. They include: 1) integrating women into development, 2) women's economic participation, 3) education, training, and employment, 4) raising the age at marriage, 5) the active involvement of men in all areas of family responsibility, and 6) the ratification of the Convention on the Elimination of All Forms of Discrimination against Women. Several important areas potentially relevant to population issues which were omitted from the Conference recommendations are identified and discussed--namely, the situation of women (in particular, older women, women who are the sole supporters of families, and women and migration) and the situation of women in times of severe economic adversity. Finally, progress made with respect to data on women is highlighted, and caution is advised with respect to continued calls for new data. In contrast to the Nairobi Forward-Looking Strategies for the Advancement of Women, the recommendations are noted for implying an almost unresolvable conflict between women's biological and economic roles. However, it is pointed out that the goals of the Convention on the Elimination of All Forms of Discrimination against Women for full equality of men and women would require that the same choices be available to both sexes with respect to labor force participation. While it is too soon to have a clear perspective on the pace and direction of change during the past 5 years, the author finds it impossible to be optimistic about current trends because, in too many areas, progress regarding women has either stagnated or moved into reverse gear. The disappointing record is partially attributed to the tendency for policy makers to see the promotion of economic growth through sound economic policy and advancing the status of women as competing rather than

  4. Contaminant effects on Great Lakes' fish-eating birds: a population perspective

    USGS Publications Warehouse

    Heinz, G.H.

    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

  5. Reproduction and population levels of Peruvian Guano Birds, 1980 to 1986

    NASA Astrophysics Data System (ADS)

    Tovar, H.; GuilléN, V.; Cabrera, D.

    1987-12-01

    The three species of guano birds, guanay cormorant (Phalacrocorax bougainvillii), Peruvian booby (Sula variegate), and Peruvian pelican (Pelecanus occidentalis thagus), depend mainly on the Peruvian anchovy (Engraulis ringens) for sustenance. A naturally occurring limitation on the population size of these birds is the oceanographic phenomenon known as "El Niño". The industrialization of the anchovy fishery during the 1960s and 1970s has also affected seabird populations: The annual extraction of huge volumes offish has decreased the availability of food for the guano birds, causing large population fluctuations and considerable changes in the relative abundance of the birds. Because of its great intensity and duration, the 1982-1983 El Niño caused high avian mortality, depressing populations to levels from which they have not yet recovered.

  6. Global population collapse in a superabundant migratory bird and illegal trapping in China.

    PubMed

    Kamp, Johannes; Oppel, Steffen; Ananin, Alexandr A; Durnev, Yurii A; Gashev, Sergey N; Hölzel, Norbert; Mishchenko, Alexandr L; Pessa, Jorma; Smirenski, Sergey M; Strelnikov, Evgenii G; Timonen, Sami; Wolanska, Kolja; Chan, Simba

    2015-12-01

    Persecution and overexploitation by humans are major causes of species extinctions. Rare species, often confined to small geographic ranges, are usually at highest risk, whereas extinctions of superabundant species with very large ranges are rare. The Yellow-breasted Bunting (Emberiza aureola) used to be one of the most abundant songbirds of the Palearctic, with a very large breeding range stretching from Scandinavia to the Russian Far East. Anecdotal information about rapid population declines across the range caused concern about unsustainable trapping along the species' migration routes. We conducted a literature review and used long-term monitoring data from across the species' range to model population trend and geographical patterns of extinction. The population declined by 84.3-94.7% between 1980 and 2013, and the species' range contracted by 5000 km. Quantitative evidence from police raids suggested rampant illegal trapping of the species along its East Asian flyway in China. A population model simulating an initial harvest level of 2% of the population, and an annual increase of 0.2% during the monitoring period produced a population trajectory that matched the observed decline. We suggest that trapping strongly contributed to the decline because the consumption of Yellow-breasted Bunting and other songbirds has increased as a result of economic growth and prosperity in East Asia. The magnitude and speed of the decline is unprecedented among birds with a comparable range size, with the exception of the Passenger Pigeon (Ectopistes migratorius), which went extinct in 1914 due to industrial-scale hunting. Our results demonstrate the urgent need for an improved monitoring of common and widespread species' populations, and consumption levels throughout East Asia. PMID:26059233

  7. A method of studying wild bird populations by mist-netting and banding

    USGS Publications Warehouse

    Stamm, D.D.; Davis, D.E.; Robbins, C.S.

    1960-01-01

    1. Progress is reported toward development of a method of bird-population study based on mist-netting and banding. A definite pattern of arrangement and schedule of operation are presented. 2. Nets were operated for a total of 4200 net-hours during which 966 captures were made (23.0 birds per 100 net-hours). A total of 431 adult breeding birds were banded and 38 per cent of them were recaptured. 3. A breeding bird census was made simultaneously in the same area by the Williams spot-mapping technique. 4. Estimates of population by recapture agreed closely with the spot-mappmg census. 5. Some birds are demonstrated to have overlapping home-ranges much larger than their singing territories. 6. Recruitment and net-shyness distort recapture estimates of population .but the method allows detection and assessment of their influence in the population dealt with here. 7. The method produced integrated information on population density and dynamics, movement and behavior. 8. The procedure is especially well adapted to studies of disease agents in bird populations. 9. A simple scheme for description of the habitat in terms of relative abundance and frequency of occurrence of tree species was used.

  8. Temporally increasing spatial synchrony of North American temperature and bird populations

    NASA Astrophysics Data System (ADS)

    Koenig, Walter D.; Liebhold, Andrew M.

    2016-06-01

    The ecological impacts of modern global climate change are detectable in a wide variety of phenomena, ranging from shifts in species ranges to changes in community composition and human disease dynamics. So far, however, little attention has been given to temporal changes in spatial synchrony--the coincident change in abundance or value across the landscape--despite the importance of environmental synchrony as a driver of population trends and the central role of environmental variability in population rescue and extinction. Here we demonstrate that across North America, spatial synchrony of a significant proportion of 49 widespread North American wintering bird species has increased over the past 50 years--the period encompassing particularly intense anthropogenic effects in climate--paralleling significant increases in spatial synchrony of mean maximum air temperature. These results suggest the potential for increased spatial synchrony in environmental factors to be affecting a wide range of ecological phenomena. These effects are likely to vary, but for North American wildlife species, increased spatial synchrony driven by environmental factors may be the basis for a previously unrecognized threat to their long-term persistence in the form of more synchronized population dynamics reducing the potential for demographic rescue among interacting subpopulations.

  9. Impact of Spring Bird Migration on the Range Expansion of Ixodes scapularis Tick Population.

    PubMed

    Wu, Xiaotian; Röst, Gergely; Zou, Xingfu

    2016-01-01

    Many observational studies suggest that seasonal migratory birds play an important role in spreading Ixodes scapularis, a vector of Lyme disease, along their migratory flyways, and they are believed to be responsible for geographic range expansion of I. scapularis in Canada. However, the interplay between the dynamics of I. scapularis on land and migratory birds in the air is not well understood. In this study, we develop a periodic delay meta-population model which takes into consideration the local landscape for tick reproduction within patches and the times needed for ticks to be transported by birds between patches. Assuming that the tick population is endemic in the source region, we find that bird migration may boost an already established tick population at the subsequent region and thus increase the risk to humans, or bird migration may help ticks to establish in a region where the local landscape is not appropriate for ticks to survive in the absence of bird migration, imposing risks to public health. This theoretical study reveals that bird migration plays an important role in the geographic range expansion of I. scapularis, and therefore our findings may suggest some strategies for Lyme disease prevention and control. PMID:26688012

  10. Population trends of North American shorebirds based on the International Shorebird Survey

    USGS Publications Warehouse

    Howe, M.A.; Geissler, P.H.; Harrington, B.A.

    1989-01-01

    Shorebirds (Charadiiformes) are prime candidates for population decline because of their dependence on wetlands that are being lost at a rapid pace. Thirty-six of the 49 species of shorebirds that breed in North America spend most of the year in Latin America. Because populations of most species breed and winter at remote sites , it may be feasible to monitor their numbers at migration stopovers. In this study, we used statistical trend analysis methods, developed for the North American Breeding Bird Survey, to analyze data on shorebird populations during south-bound migration in the United States. Survey data were collected by volunteers in the International Shorebird Survey (ISS). Methodological concerns over both the ISS and the trend analysis procedures are discussed in detail and biological interpretations of the results are suggested.

  11. Winter marine bird and sea otter abundance of Prince William Sound, Alaska: Trends following the t/v Exxon Valdez oil spill from 1990-94. Restoration project 94159. Exxon Valdez oil spill restoration project final report

    SciTech Connect

    Agler, B.A.; Seiser, P.E.; Kendall, S.J.; Irons, D.B.

    1995-05-01

    We conducted small boat surveys to determine population abundance of marine birds and sea otters (Enhydra lutris) in Prince William Sound, Alaska during March 1994. We observed 45 bird and 8 mammal species in Prince William Sound, and we estimated that 320,470 + or - 63,640 marine birds were present. We estimated trends in the March population estimates from 1990-94 by determining whether estimates in the oiled zone changed at the same rate as those in the unoiled zone. For Prince William Sound as a whole, we also examined the population trends from 1990-94 using regression analyses. We found significant positive trends for harlequin duck (Histrionicus), goldeneye, merganser, bald eagle (Haliaeetus leucocephalus), black-legged kittiwake (Rissa tridactyla) and gull (Larus and Rissa spp.) populations. We also examined the relative abundance of marine bird species groups from 1972 to 1994. During March 1994, we estimated that the sea otter population was 7,746 + or - 2,073 otters. We found no difference in the rate of change between the oiled and unoiled zones from 1990-94, and there was no significant trend in the total number of sea otters in Prince William Sound from 1990-94.

  12. A comparison of landscapes occupied by increasing and decreasing populations of grassland birds.

    PubMed

    Veech, Joseph A

    2006-10-01

    For several decades, many grassland bird species have been declining in abundance throughout the Midwest and Great Plains regions of the United States, possibly due to loss of natural grassland habitat and increasing urbanization. I used 20 years of data from the North American Breeding Bird Survey to identify increasing, decreasing, and stable populations of 36 grassland-nesting bird species. I characterized the immediate landscape (circle with radius = 30 km) surrounding each population based on data from the National Resources Inventory. For each landscape, I calculated the proportion of eight different land-cover types: restored grassland, rangeland, cultivated cropland, pasture, noncultivated cropland, forest, urban land, and water. Using a null model, I compared landscape composition of increasing, decreasing, and stable populations. As predicted on the basis of the habitat preferences of grassland birds, increasing populations inhabited landscapes that contained significantly more restored grassland and rangeland but significantly less forest land and urban land than landscapes inhabited by decreasing populations. There was no significant difference in the proportion of cropland within the landscapes of increasing and decreasing populations, although cropland composed a large proportion (>30%) of many landscapes. In contrast, restored grassland typically composed a very small proportion (<3.5%) of total land cover, yet it was significantly more common in the landscapes of increasing than decreasing populations. These results suggest that grassland birds may benefit from government initiatives, such as the Conservation Reserve Program, that promote the restoration of grassland at a landscape scale. PMID:17002760

  13. Limited catching bias in a wild population of birds with near-complete census information.

    PubMed

    Simons, Mirre J P; Winney, Isabel; Nakagawa, Shinichi; Burke, Terry; Schroeder, Julia

    2015-08-01

    Animal research often relies on catching wild animals; however, individuals may have different trappability, and this can generate bias. We studied bias in mist netting, the main method for catching wild birds. The unusually high resighting rate in our study population-house sparrows (Passer domesticus) on Lundy Island (England)-allowed us to obtain accurate estimates of the population size. This unique situation enabled us to test for catching bias in mist netting using deviations from the expected Poisson distribution. There was no evidence that a fraction of the birds in the population consistently remained uncaught. However, we detected a different bias: More birds than expected were captured only once within a year. This bias probably resulted from a mixture of fieldworkers sometimes ignoring rapid recaptures and birds becoming net shy after their first capture. We had sufficient statistical power with the available data to detect a substantial uncaught fraction. Therefore, our data are probably unbiased toward catching specific individuals from our population. Our analyses demonstrate that intensively monitored natural insular populations, in which population size can be estimated precisely, provide the potential to address important unanswered questions without concerns about a fraction of the population remaining uncaught. Our approach can help researchers to test for catching bias in closely monitored wild populations for which reliable estimates of population size and dispersal are available. PMID:26380681

  14. Developing accurate survey methods for estimating population sizes and trends of the critically endangered Nihoa Millerbird and Nihoa Finch.

    USGS Publications Warehouse

    Gorresen, P. Marcos; Camp, Richard J.; Brinck, Kevin W.; Farmer, Chris

    2012-01-01

    Point-transect surveys indicated that millerbirds were more abundant than shown by the striptransect method, and were estimated at 802 birds in 2010 (95%CI = 652 – 964) and 704 birds in 2011 (95%CI = 579 – 837). Point-transect surveys yielded population estimates with improved precision which will permit trends to be detected in shorter time periods and with greater statistical power than is available from strip-transect survey methods. Mean finch population estimates and associated uncertainty were not markedly different among the three survey methods, but the performance of models used to estimate density and population size are expected to improve as the data from additional surveys are incorporated. Using the pointtransect survey, the mean finch population size was estimated at 2,917 birds in 2010 (95%CI = 2,037 – 3,965) and 2,461 birds in 2011 (95%CI = 1,682 – 3,348). Preliminary testing of the line-transect method in 2011 showed that it would not generate sufficient detections to effectively model bird density, and consequently, relatively precise population size estimates. Both species were fairly evenly distributed across Nihoa and appear to occur in all or nearly all available habitat. The time expended and area traversed by observers was similar among survey methods; however, point-transect surveys do not require that observers walk a straight transect line, thereby allowing them to avoid culturally or biologically sensitive areas and minimize the adverse effects of recurrent travel to any particular area. In general, pointtransect surveys detect more birds than strip-survey methods, thereby improving precision and resulting population size and trend estimation. The method is also better suited for the steep and uneven terrain of Nihoa

  15. A retrospective perspective: evaluating population changes by repeating historic bird surveys

    USGS Publications Warehouse

    Igl, L.D.; Johnson, D.H.

    2005-01-01

    Acquiring an accurate picture of the changes in bird populations often involves a tradeoff between the time and effort required to complete the surveys and the number of years spent surveying the bird populations. An alternative approach to long-term monitoring efforts is to collect current data and contrast those with data collected earlier in a similar fashion on the same study site(s). To evaluate changes in bird populations, we repeated two extensive surveys, one in North Dakota (1967 vs. 1992-1993) and the other in the Platte River Valley of Nebraska (1979-1980 vs. 2001), where large areas of native vegetation had been converted to agriculture. We use these examples and others from the literature to illustrate the advantages and disadvantages of using historical data as a frame of reference for population changes.

  16. Breeding bird populations and habitat associations within the Savannah River Site (SRS).

    SciTech Connect

    Gauthreaux, Sidney, A.; Steven J. Wagner.

    2005-06-29

    Gauthreaux, Sidney, A., and Steven J. Wagner. 2005. Breeding bird populations and habitat associations within the Savannah River Site (SRS). Final Report. USDA Forest Service, Savannah River, Aiken, SC. 48 pp. Abstract: During the 1970's and 1980's a dramatic decline occurred in the populations of Neotropical migratory birds, species that breed in North America and winter south of the border in Central and South America and in the Caribbean. In 1991 an international initiative was mounted by U. S. governmental land management agencies, nongovernmental conservation agencies, and the academic and lay ornithological communities to understand the decline of Neotropical migratory birds in the Americas. In cooperation with the USDA Forest Service - Savannah River (FS - SR) we began 1992 a project directed to monitoring population densities of breeding birds using the Breeding Bird Census (BBC) methodology in selected habitats within the Savannah River Site SRS. In addition we related point count data on the occurrence of breeding Neotropical migrants and other bird species to the habitat data gathered by the Forest Inventory and Analysis (FIA) program of the USDA Forest Service and data on habitat treatments within forest stands.

  17. Global Population Trends: Challenges Facing World Leaders.

    ERIC Educational Resources Information Center

    Scommegna, Paola, Ed.

    This pamphlet explores the dynamics of world population, highlighting steps world leaders can take to address population problems and improve the lives of people worldwide. With jet-age transportation and electronic communication, economic and social interdependence of nations is greater than ever before and is likely to increase in the future.…

  18. Limited catching bias in a wild population of birds with near-complete census information

    PubMed Central

    Simons, Mirre J P; Winney, Isabel; Nakagawa, Shinichi; Burke, Terry; Schroeder, Julia

    2015-01-01

    Animal research often relies on catching wild animals; however, individuals may have different trappability, and this can generate bias. We studied bias in mist netting, the main method for catching wild birds. The unusually high resighting rate in our study population—house sparrows (Passer domesticus) on Lundy Island (England)—allowed us to obtain accurate estimates of the population size. This unique situation enabled us to test for catching bias in mist netting using deviations from the expected Poisson distribution. There was no evidence that a fraction of the birds in the population consistently remained uncaught. However, we detected a different bias: More birds than expected were captured only once within a year. This bias probably resulted from a mixture of fieldworkers sometimes ignoring rapid recaptures and birds becoming net shy after their first capture. We had sufficient statistical power with the available data to detect a substantial uncaught fraction. Therefore, our data are probably unbiased toward catching specific individuals from our population. Our analyses demonstrate that intensively monitored natural insular populations, in which population size can be estimated precisely, provide the potential to address important unanswered questions without concerns about a fraction of the population remaining uncaught. Our approach can help researchers to test for catching bias in closely monitored wild populations for which reliable estimates of population size and dispersal are available. PMID:26380681

  19. From daily movements to population distributions: weather affects competitive ability in a guild of soaring birds.

    PubMed

    Shepard, Emily L C; Lambertucci, Sergio A

    2013-11-01

    The ability of many animals to access and exploit food is dependent on the ability to move. In the case of scavenging birds, which use soaring flight to locate and exploit ephemeral resources, the cost and speed of movement vary with meteorological factors. These factors are likely to modify the nature of interspecific interactions, as well as individual movement capacity, although the former are less well understood. We used aeronautical models to examine how soaring performance varies with weather within a guild of scavenging birds and the consequences this has for access to a common resource. Birds could be divided broadly into those with low wing loading that are more competitive in conditions with weak updraughts and low winds (black vultures and caracaras), and those with high wing loading that are well adapted for soaring in strong updraughts and moderate to high winds (Andean condors). Spatial trends in meteorological factors seem to confine scavengers with high wing loading to the mountains where they out-compete other birds; a trend that is borne out in worldwide distributions of the largest species. However, model predictions and carcass observations suggest that the competitive ability of these and other birds varies with meteorological conditions in areas where distributions overlap. This challenges the view that scavenging guilds are structured by fixed patterns of dominance and suggests that competitive ability varies across spatial and temporal scales, which may ultimately be a mechanism promoting diversity among aerial scavengers. PMID:24026471

  20. From daily movements to population distributions: weather affects competitive ability in a guild of soaring birds

    PubMed Central

    Shepard, Emily L. C.; Lambertucci, Sergio A.

    2013-01-01

    The ability of many animals to access and exploit food is dependent on the ability to move. In the case of scavenging birds, which use soaring flight to locate and exploit ephemeral resources, the cost and speed of movement vary with meteorological factors. These factors are likely to modify the nature of interspecific interactions, as well as individual movement capacity, although the former are less well understood. We used aeronautical models to examine how soaring performance varies with weather within a guild of scavenging birds and the consequences this has for access to a common resource. Birds could be divided broadly into those with low wing loading that are more competitive in conditions with weak updraughts and low winds (black vultures and caracaras), and those with high wing loading that are well adapted for soaring in strong updraughts and moderate to high winds (Andean condors). Spatial trends in meteorological factors seem to confine scavengers with high wing loading to the mountains where they out-compete other birds; a trend that is borne out in worldwide distributions of the largest species. However, model predictions and carcass observations suggest that the competitive ability of these and other birds varies with meteorological conditions in areas where distributions overlap. This challenges the view that scavenging guilds are structured by fixed patterns of dominance and suggests that competitive ability varies across spatial and temporal scales, which may ultimately be a mechanism promoting diversity among aerial scavengers. PMID:24026471

  1. Dynamics of a recovering Arctic bird population: the importance of climate, density dependence, and site quality.

    PubMed

    Bruggeman, Jason E; Swem, Ted; Andersen, David E; Kennedy, Patricia L; Nigro, Debora

    2015-10-01

    Intrinsic and extrinsic factors affect vital rates and population-level processes, and understanding these factors is paramount to devising successful management plans for wildlife species. For example, birds time migration in response, in part, to local and broadscale climate fluctuations to initiate breeding upon arrival to nesting territories, and prolonged inclement weather early in the breeding season can inhibit egg-laying and reduce productivity. Also, density-dependent regulation occurs in raptor populations, as territory size is related to resource availability. Arctic Peregrine Falcons (Falco peregrinus tundrius; hereafter Arctic peregrine) have a limited and northern breeding distribution, including the Colville River Special Area (CRSA) in the National Petroleum Reserve-Alaska, USA. We quantified influences of climate, topography, nest productivity, prey habitat, density dependence, and interspecific competition affecting Arctic peregrines in the CRSA by applying the Dail-Madsen model to estimate abundance and vital rates of adults on nesting cliffs from 1981 through 2002. Arctic peregrine abundance increased throughout the 1980s, which spanned the population's recovery from DDT-induced reproductive failure, until exhibiting a stationary trend in the 1990s. Apparent survival rate (i.e., emigration; death) was negatively correlated with the number of adult Arctic peregrines on the cliff the previous year, suggesting effects of density-dependent population regulation. Apparent survival and arrival rates (i.e., immigration; recruitment) were higher during years with earlier snowmelt and milder winters, and apparent survival was positively correlated with nesting season maximum daily temperature. Arrival rate was positively correlated with average Arctic peregrine productivity along a cliff segment from the previous year and initial abundance was positively correlated with cliff height. Higher cliffs with documented higher productivity (presumably

  2. Estimating population change from count data: application to the North American Breeding Bird Survey

    USGS Publications Warehouse

    Link, W.A.; Sauer, J.R.

    1998-01-01

    For birds and many other animal taxa, surveys that collect count data form a primary source of information on population change. Because counts are only indices to population size, care must be taken in using them in analyses of population change. Temporal or geographic differences in the proportion of animals counted can be misinterpreted as differences in population size. Therefore, temporally or geographically varying factors that influence the proportion of animals counted must be incorporated as covariables in the analysis of population parameters from count data. We describe the North American Breeding Bird Survey (BBS) for illustration. The BBS is a major, landscape-level survey of birds in North America; it is typical of many count surveys, in that the same sample units (survey routes) are sampled each year, and change is modeled on these routes over time. We identify covariables related to observer ability, the omission of which can bias estimation of population change from BBS data. Controlling for observer effects or other potential sources of confounding requires the specification of models relating counts to population size. We begin with a partial model specification relating expected counts to population sizes; we describe estimators currently in use in relation to this partial specification. Additional assumptions lead to a class of over-dispersed multinomial models, for which we describe estimators of population change and procedures for parsimonious model selection. We illustrate the use of over-dispersed multinomial models by an application to data for Carolina Wren (Thryothorus ludovicianus).

  3. Population trends among Jamaican reef corals

    NASA Astrophysics Data System (ADS)

    Porter, James W.; Woodley, Jeremy D.; Jason Smith, G.; Neigel, Joseph E.; Battey, James F.; Dallmeyer, Dorinda G.

    1981-11-01

    Disturbance has been cited as a potentially important agent in structuring ecological communities by modifying the effects of competition1-5. Catastrophic disturbance has also been proposed as a factor promoting the coexistence of competing species in highly diverse tropical ecosystems such as rain forests and coral reefs2,6-11. Here we describe patterns of recruitment and mortality among reef corals over 4 yr at several depths on the reefs of Discovery Bay, Jamaica, which were struck by Hurricane Alien on 6 August 198012. Photographic quadrats monitored since 1976 on a shallow water reef showed a negative correlation between coral abundance and mortality which was not offset by compensatory patterns of recruitment. This slow trend in the disproportionate reduction of rarer, competitively inferior species was reversed by Hurricane Alien, with storm-induced mortality being greatest in the most abundant species. On deeper reef stations, undisturbed by the storm, slower rates of colony loss were compensated for by commensurate rates of colony recruitment. Thus, patterns of differential mortality and recruitment contribute to the maintenance of high species diversity in this tropical marine ecosystem.

  4. Estimating trends in alligator populations from nightlight survey data

    USGS Publications Warehouse

    Fujisaki, Ikuko; Mazzotti, F.J.; Dorazio, R.M.; Rice, K.G.; Cherkiss, M.; Jeffery, B.

    2011-01-01

    Nightlight surveys are commonly used to evaluate status and trends of crocodilian populations, but imperfect detection caused by survey- and location-specific factors makes it difficult to draw population inferences accurately from uncorrected data. We used a two-stage hierarchical model comprising population abundance and detection probability to examine recent abundance trends of American alligators (Alligator mississippiensis) in subareas of Everglades wetlands in Florida using nightlight survey data. During 2001-2008, there were declining trends in abundance of small and/or medium sized animals in a majority of subareas, whereas abundance of large sized animals had either demonstrated an increased or unclear trend. For small and large sized class animals, estimated detection probability declined as water depth increased. Detection probability of small animals was much lower than for larger size classes. The declining trend of smaller alligators may reflect a natural population response to the fluctuating environment of Everglades wetlands under modified hydrology. It may have negative implications for the future of alligator populations in this region, particularly if habitat conditions do not favor recruitment of offspring in the near term. Our study provides a foundation to improve inferences made from nightlight surveys of other crocodilian populations. ?? 2011 US Government.

  5. Estimating trends in alligator populations from nightlight survey data

    USGS Publications Warehouse

    Fujisaki, Ikuko; Mazzotti, Frank J.; Dorazio, Robert M.; Rice, Kenneth G.; Cherkiss, Michael; Jeffery, Brian

    2011-01-01

    Nightlight surveys are commonly used to evaluate status and trends of crocodilian populations, but imperfect detection caused by survey- and location-specific factors makes it difficult to draw population inferences accurately from uncorrected data. We used a two-stage hierarchical model comprising population abundance and detection probability to examine recent abundance trends of American alligators (Alligator mississippiensis) in subareas of Everglades wetlands in Florida using nightlight survey data. During 2001–2008, there were declining trends in abundance of small and/or medium sized animals in a majority of subareas, whereas abundance of large sized animals had either demonstrated an increased or unclear trend. For small and large sized class animals, estimated detection probability declined as water depth increased. Detection probability of small animals was much lower than for larger size classes. The declining trend of smaller alligators may reflect a natural population response to the fluctuating environment of Everglades wetlands under modified hydrology. It may have negative implications for the future of alligator populations in this region, particularly if habitat conditions do not favor recruitment of offspring in the near term. Our study provides a foundation to improve inferences made from nightlight surveys of other crocodilian populations.

  6. Recent status and trends of the land bird avifauna on Saipan, Mariana Islands, with emphasis on the endangered Nightingale Reed-warbler Acrocephalus luscinia

    USGS Publications Warehouse

    Camp, R.J.; Pratt, T.K.; Marshall, A.P.; Amidon, F.; Williams, L.L.

    2009-01-01

    The avifauna of the Mariana Islands, an archipelago in the western Pacific, faces the threats of rapid economic development and the spread of non-native species, particularly a devastating predator, Brown Tree Snake Boiga irregularis. In this paper, we examine the status and trends of the land bird fauna of Saipan Island based on three island-wide surveys conducted in 1982, 1997, and 2007. During this period, the human population on Saipan increased more than four-fold and much of the island has been developed. The surveys employed standard point-transect methods based on Distance Sampling. Remarkably, we found nearly all species of land birds - 11 native species and three introduced species - to be common or abundant. The exception was the Micronesian Megapode Megapodius laperouse, a historically rare species that was not observed on the 2007 survey, although it does persist on Saipan and other Mariana islands. A comparison of species densities among the three surveys showed that seven species, mainly fruit and seed-eaters, had increased and three species of insectivorous birds had decreased - Rufous Fantail Rhipidura rufifrons, Nightingale Reed-warbler Acrocephalus luscinia, and Golden White-eye Cleptornis marchei. Of these three, Nightingale Reed-warbler is listed as Endangered on the IUCN Red List and as an Endangered Species by the U.S. Fish and Wildlife Service. Reed-warbler densities on Saipan decreased by more than half between 1982 and 2007. Although point transect sampling worked well for this species, density estimates and trends assessment could be improved by reallocating sampling stations among habitats and by more frequent sampling. ?? BirdLife International 2009.

  7. Habitat-Specific Population Growth of a Farmland Bird

    PubMed Central

    Arlt, Debora; Forslund, Pär; Jeppsson, Tobias; Pärt, Tomas

    2008-01-01

    Background To assess population persistence of species living in heterogeneous landscapes, the effects of habitat on reproduction and survival have to be investigated. Methodology/Principal Findings We used a matrix population model to estimate habitat-specific population growth rates for a population of northern wheatears Oenanthe oenanthe breeding in farmland consisting of a mosaic of distinct habitat (land use) types. Based on extensive long-term data on reproduction and survival, habitats characterised by tall field layers (spring- and autumn-sown crop fields, ungrazed grasslands) displayed negative stochastic population growth rates (log λs: −0.332, −0.429, −0.168, respectively), that were markedly lower than growth rates of habitats characterised by permanently short field layers (pastures grazed by cattle or horses, and farmyards, log λs: −0.056, +0.081, −0.059). Although habitats differed with respect to reproductive performance, differences in habitat-specific population growth were largely due to differences in adult and first-year survival rates, as shown by a life table response experiment (LTRE). Conclusions/Significance Our results show that estimation of survival rates is important for realistic assessments of habitat quality. Results also indicate that grazed grasslands and farmyards may act as source habitats, whereas crop fields and ungrazed grasslands with tall field layers may act as sink habitats. We suggest that the strong decline of northern wheatears in Swedish farmland may be linked to the corresponding observed loss of high quality breeding habitat, i.e. grazed semi-natural grasslands. PMID:18714351

  8. The effects of predation by wading birds (Ardeidae) and blue crabs ( Callinectes sapidus) on the population size structure of the common mummichog, Fundulus heteroclitus

    NASA Astrophysics Data System (ADS)

    Kneib, R. T.

    1982-02-01

    Preliminary observations suggested that predation by herons and egretsaffected the size structure of a mummichog ( Fundulus heteroclitus) population in Tar Landing Marsh, North Carolina. The hypothesis was tested by placing 300 mummichogs represented equally in three size classes into each half of an enclosed, divided, high marsh pool. Nylon cord was strung in a grid over one side to inhibit predation by wading birds. Although mummichog losses were higher in the side of the pool which was open to bird predation, the same trend in size-specific losses also occurred in the bird-exclusion side. Repeating the experiment after the removal of several blue crabs ( Callinectes sapidus) improved mummichog survivorship and suggested that crabs and not birds were responsible for the fish losses previously observed. In a final experiment, birds were excluded and crabs were removed from one side but added to the other side of the pool. After 24 days losses due to C. sapidus occurred in all mummichog size classes, but size-specific predation by blue crabs produced the highest losses (90%) among the largest (>70 mm total length) fish. Blue crab predation on mummichog populations may influence the community structure of salt marsh infauna and may also function in the movement of marsh production to open coastal waters.

  9. Very Low Population Structure in a Highly Mobile and Wide-Ranging Endangered Bird Species

    PubMed Central

    Kvistad, Lynna; Ingwersen, Dean; Pavlova, Alexandra; Bull, James K.; Sunnucks, Paul

    2015-01-01

    The loss of biodiversity following fragmentation and degradation of habitat is a major issue in conservation biology. As competition for resources increases following habitat loss and fragmentation, severe population declines may occur even in common, highly mobile species; such demographic decline may cause changes within the population structure of the species. The regent honeyeater, Anthochaera phrygia, is a highly nomadic woodland bird once common in its native southeast Australia. It has experienced a sharp decline in abundance since the late 1970s, following clearing of large areas of its preferred habitat, box-ironbark woodland, within the last 200 years. A captive breeding program has been established as part of efforts to restore this species. This study used genetic data to examine the range-wide population structure of regent honeyeaters, including spatial structure, its change through time, sex differences in philopatry and mobility, and genetic differences between the captive and wild populations. There was low genetic differentiation between birds captured in different geographic areas. Despite the recent demographic decline, low spatial structure appears to have some temporal consistency. Both sexes appear to be highly mobile, and there does not seem to be significant genetic differentiation between the captive and wild populations. We conclude that management efforts for survival of this species, including habitat protection, restoration, and release of captive-bred birds into the wild, can treat the species as effectively a single genetic population. PMID:26649426

  10. Very Low Population Structure in a Highly Mobile and Wide-Ranging Endangered Bird Species.

    PubMed

    Kvistad, Lynna; Ingwersen, Dean; Pavlova, Alexandra; Bull, James K; Sunnucks, Paul

    2015-01-01

    The loss of biodiversity following fragmentation and degradation of habitat is a major issue in conservation biology. As competition for resources increases following habitat loss and fragmentation, severe population declines may occur even in common, highly mobile species; such demographic decline may cause changes within the population structure of the species. The regent honeyeater, Anthochaera phrygia, is a highly nomadic woodland bird once common in its native southeast Australia. It has experienced a sharp decline in abundance since the late 1970s, following clearing of large areas of its preferred habitat, box-ironbark woodland, within the last 200 years. A captive breeding program has been established as part of efforts to restore this species. This study used genetic data to examine the range-wide population structure of regent honeyeaters, including spatial structure, its change through time, sex differences in philopatry and mobility, and genetic differences between the captive and wild populations. There was low genetic differentiation between birds captured in different geographic areas. Despite the recent demographic decline, low spatial structure appears to have some temporal consistency. Both sexes appear to be highly mobile, and there does not seem to be significant genetic differentiation between the captive and wild populations. We conclude that management efforts for survival of this species, including habitat protection, restoration, and release of captive-bred birds into the wild, can treat the species as effectively a single genetic population. PMID:26649426

  11. Quantifying the detrimental impacts of land-use and management change on European forest bird populations.

    PubMed

    Wade, Amy S I; Barov, Boris; Burfield, Ian J; Gregory, Richard D; Norris, Ken; Butler, Simon J

    2013-01-01

    The ecological impacts of changing forest management practices in Europe are poorly understood despite European forests being highly managed. Furthermore, the effects of potential drivers of forest biodiversity decline are rarely considered in concert, thus limiting effective conservation or sustainable forest management. We present a trait-based framework that we use to assess the detrimental impact of multiple land-use and management changes in forests on bird populations across Europe. Major changes to forest habitats occurring in recent decades, and their impact on resource availability for birds were identified. Risk associated with these changes for 52 species of forest birds, defined as the proportion of each species' key resources detrimentally affected through changes in abundance and/or availability, was quantified and compared to their pan-European population growth rates between 1980 and 2009. Relationships between risk and population growth were found to be significantly negative, indicating that resource loss in European forests is an important driver of decline for both resident and migrant birds. Our results demonstrate that coarse quantification of resource use and ecological change can be valuable in understanding causes of biodiversity decline, and thus in informing conservation strategy and policy. Such an approach has good potential to be extended for predictive use in assessing the impact of possible future changes to forest management and to develop more precise indicators of forest health. PMID:23704997

  12. The dynamics, transmission, and population impacts of avian malaria in native hawaiian birds: A modeling approach

    USGS Publications Warehouse

    Samuel, M.D.; Hobbelen, P.H.F.; Decastro, F.; Ahumada, J.A.; Lapointe, D.A.; Atkinson, C.T.; Woodworth, B.L.; Hart, P.J.; Duffy, D.C.

    2011-01-01

    We developed an epidemiological model of avian malaria (Plasmodium relictum) across an altitudinal gradient on the island of Hawaii that includes the dynamics of the host, vector, and parasite. This introduced mosquito-borne disease is hypothesized to have contributed to extinctions and major shifts in the altitudinal distribution of highly susceptible native forest birds. Our goal was to better understand how biotic and abiotic factors influence the intensity of malaria transmission and impact on susceptible populations of native Hawaiian forest birds. Our model illustrates key patterns in the malaria-forest bird system: high malaria transmission in low-elevation forests with minor seasonal or annual variation in infection;episodic transmission in mid-elevation forests with site-to-site, seasonal, and annual variation depending on mosquito dynamics;and disease refugia in high-elevation forests with only slight risk of infection during summer. These infection patterns are driven by temperature and rainfall effects on parasite incubation period and mosquito dynamics across an elevational gradient and the availability of larval habitat, especially in mid-elevation forests. The results from our model suggest that disease is likely a key factor in causing population decline or restricting the distribution of many susceptible Hawaiian species and preventing the recovery of other vulnerable species. The model also provides a framework for the evaluation of factors influencing disease transmission and alternative disease control programs, and to evaluate the impact of climate change on disease cycles and bird populations. ??2011 by the Ecological Society of America.

  13. Chapter 8. Effects of fire on bird populations in mixed-grass prairie

    USGS Publications Warehouse

    Johnson, D.H.

    1997-01-01

    The mixed-grass prairie is one of the largest ecosystems in North America, originally covering about 69 million hectares (Bragg and Steuter 1995). Although much of the natural vegetation has been replaced by cropland and other uses (Samson and Knopf 1994, Bragg and Steuter 1995), significant areas have been preserved in national wildlife refuges, waterfowl production areas, state game management areas, and nature preserves. Mixed-grass prairie evolved with fire (Bragg 1995), and fire is frequently used as a management tool for prairie (Berkey et al. 1993). Much of the mixed-grass prairie that has been protected is managed to enhance the reproductive success of waterfowl and other gamebirds, but nongame birds now are receiving increasing emphasis. Despite the importance of the area to numerous species of birds and the aggressive management applied to many sites, relatively little is known about the effects of fire on the suitability of mixed-grass prairie for breeding birds. Several studies have examined effects of fire on breeding birds in the tallgrass prairie (e.g., Tester and Marshall 1961, Eddleman 1974, Halvorsen and Anderson 1983, Westenmeier and Buhnerkempe 1983, Zimmerman 1992, Herkert 1994), in western sagebrush grasslands (Peterson and Best 1987), and in shrubsteppe (Bock and Bock 1987). Studies of fire effects in the mixed-grass prairie are limited. Huber and Steuter (1984) examined the effects on birds during the breeding season following an early-May prescribed burn on a 122-ha site in South Dakota. They contrasted the bird populations on that site to those on a nearby 462-ha unburned site that had been lightly grazed by bison (Bison bison). Pylypec (1991) monitored breeding bird populations occurring in fescue prairies of Canada on a single 12.9-ha burned area and on an adjacent 5.6-ha unburned fescue prairie for three years after a prescribed burn. This chapter describes the effects of prescribed fire on common terrestrial birds at a mixed

  14. Effects of fire on bird populations in mixed-grass prairie: Chapter 8

    USGS Publications Warehouse

    Johnson, Douglas H.

    1997-01-01

    The mixed-grass prairie is one of the largest ecosystems in North America, originally covering about 69 million hectares (Bragg and Steuter 1995). Although much of the natural vegetation has been replaced by cropland and other uses (Samson and Knopf 1994, Bragg and Steuter 1995), significant areas have been preserved in national wildlife refuges, waterfowl production areas, state game management areas, and nature preserves. Mixed-grass prairie evolved with fire (Bragg 1995), and fire is frequently used as a management tool for prairie (Berkey et al. 1993). Much of the mixed-grass prairie that has been protected is managed to enhance the reproductive success of waterfowl and other gamebirds, but nongame birds now are receiving increasing emphasis. Despite the importance of the area to numerous species of birds and the aggressive management applied to many sites, relatively little is known about the effects of fire on the suitability of mixed-grass prairie for breeding birds. Several studies have examined effects of fire on breeding birds in the tallgrass prairie (e.g., Tester and Marshall 1961, Eddleman 1974, Halvorsen and Anderson 1983, Westenmeier and Buhnerkempe 1983, Zimmerman 1992, Herkert 1994), in western sagebrush grasslands (Peterson and Best 1987), and in shrubsteppe (Bock and Bock 1987). Studies of fire effects in the mixed-grass prairie are limited. Huber and Steuter (1984) examined the effects on birds during the breeding season following an early-May prescribed burn on a 122-ha site in South Dakota. They contrasted the bird populations on that site to those on a nearby 462-ha unburned site that had been lightly grazed by bison (Bison bison). Pylypec (1991) monitored breeding bird populations occurring in fescue prairies of Canada on a single 12.9-ha burned area and on an adjacent 5.6-ha unburned fescue prairie for three years after a prescribed burn. This chapter describes the effects of prescribed fire on common terrestrial birds at a mixed

  15. Comparison of neotropical winter bird populations in isolated patches versus extensive forest

    USGS Publications Warehouse

    Robbins, C.S.; Dowell, B.A.; Dawson, D.K.; Colon, J.; Espinoza, F.; Rodriguez, J.; Sutton, R.; Vargas, T.

    1987-01-01

    Wintering birds were captured with mist nets at 12 pairs of forested sites in the New World tropics in 1984 and 1985 to compare populations in small isolated woodlands (generally 5-50 ha) with those in extensive forests (> 1,000 ha). Net-hours of effort were similar in large and small sites, as were total birds captured and banded, but species composition was very different. Members of the Todidae, Dendrocolaptidae, Formicariidae and Thraupinae were significantly more common in extensive forest than in small isolated tracts, indicating that these birds are especially vulnerable to effects of forest fragmentation. However, in winter many species of North American migrants, even species that are restricted to extensive forest during the breeding season, were just as common in small forest fragments as in extensive forest. A high percentage of the North American migrants banded in January 1984 (40 to 50 % for some species) were recaptured in 1985.

  16. Microsatellite variation in the yellowhammer Emberiza citrinella: population structure of a declining farmland bird.

    PubMed

    Lee, P L; Bradbury, R B; Wilson, J D; Flanagan, N S; Richardson, L; Perkins, A J; Krebs, J R

    2001-07-01

    In recent years, there has been much concern in the UK about population declines of widespread species in agricultural habitats. Conservation-orientated research on declining birds has focused on vital rates of survival and productivity. However, the environmental factors which may influence movements between populations of widespread species is poorly understood. Population genetic structure is an indirect description of dispersal between groups of individuals. To attempt to develop an understanding of genetic structuring in a widespread, but declining, farmland bird, we therefore investigated the yellowhammer, Emberiza citrinella, population in England and Wales using microsatellite data. Our first aim was to investigate whether there was genetic substructuring in the population. A second aim was to investigate if there was a relationship between genetic distances and various environmental variables. Finally, we analysed the microsatellite data for evidence of loss of genetic variation due to population decline. Our data showed a slight but significant structure within the yellowhammer population. This therefore cannot be considered a panmictic population. Our example from South Cumbria implies that high-altitude barriers may have a slight influence on population structure. However, on the whole, genetic distances between sample sites were not significantly correlated with geographical distances, degrees of population connectivity, high altitudes, or differences in precipitation between sites. Finally, we detected departures from mutation-drift equilibrium (excess heterozygosity), which is indicative of a loss of genetic variation through recent decline. PMID:11472532

  17. An assessment of bird habitat quality using population growth rates

    USGS Publications Warehouse

    Knutson, M.G.; Powell, L.A.; Hines, R.K.; Friberg, M.A.; Niemi, G.J.

    2006-01-01

    Survival and reproduction directly affect population growth rate (lambda) making lambda a fundamental parameter for assessing habitat quality. We used field data, literature review, and a computer simulation to predict annual productivity and lambda for several species of landbirds breeding in floodplain and upland forests in the Midwestern United States. We monitored 1735 nests of 27 species; 760 nests were in the uplands and 975 were in the floodplain. Each type of forest habitat (upland and floodplain) was a source habitat for some species. Despite a relatively low proportion of regional forest cover, the majority of species had stable or increasing populations in all or some habitats, including six species of conservation concern. In our search for a simple analog for lambda, we found that only adult apparent survival, juvenile survival, and annual productivity were correlated with lambda; daily nest survival and relative abundance estimated from point counts were not. Survival and annual productivity are among the most costly demographic parameters to measure and there does not seem to be a low-cost alternative. In addition, our literature search revealed that the demographic parameters needed to model annual productivity and lambda were unavailable for several species. More collective effort across North America is needed to fill the gaps in our knowledge of demographic parameters necessary to model both annual productivity and lambda. Managers can use habitat-specific predictions of annual productivity to compare habitat quality among species and habitats for purposes of evaluating management plans.

  18. The effects of climate change on the phenology of selected Estonian plant, bird and fish populations.

    PubMed

    Ahas, Rein; Aasa, Anto

    2006-09-01

    This paper summarises the trends of 943 phenological time-series of plants, fishes and birds gathered from 1948 to 1999 in Estonia. More than 80% of the studied phenological phases have advanced during springtime, whereas changes are smaller during summer and autumn. Significant values of plant and bird phases have advanced 5-20 days, and fish phases have advanced 10-30 days in the spring period. Estonia's average air temperature has become significantly warmer in spring, while at the same time a slight decrease in air temperature has been detected in autumn. The growing season has become significantly longer in the maritime climate area of Western Estonia. The investigated phenological and climate trends are related primarily to changes in the North Atlantic Oscillation Index (NAOI) during the winter months. Although the impact of the winter NAOI on the phases decreases towards summer, the trends of the investigated phases remain high. The trends of phenophases at the end of spring and the beginning of summer may be caused by the temperature inertia of the changing winter, changes in the radiation balance or the direct consequences of human impacts such as land use, heat islands or air pollution. PMID:16738902

  19. Population genetic structure and long-distance dispersal of a recently expanding migratory bird.

    PubMed

    Ramos, Raül; Song, Gang; Navarro, Joan; Zhang, Ruiying; Symes, Craig T; Forero, Manuela G; Lei, Fumin

    2016-06-01

    Long-distance dispersal events and their derivable increases of genetic diversity have been highlighted as important ecological and evolutionary determinants that improve performances of range-expanding species. In the context of global environmental change, specific dispersal strategies have to be understood and foreseen if we like to prevent general biodiversity impoverishment or the spread of allochthonous diseases. We explored the genetic structure and potential population mixing on the recently range-expanding European bee-eater Merops apiaster. In addition, the species is suspected of harbouring and disseminating the most relevant disease for bees and apiculture, Nosema microsporidia. In agreement with complementary ringing recovery data and morphometric measurements, genetic results on two mitochondrial genes and 12 microsatellites showed a reasonably well-structured population partitioning along its breeding distribution. Microsatellite results indicated that not only did a few birds recently disperse long distance during their return migrations and change their natal breeding areas, but also that a group of allochthonous birds together founded a new colony. Although we did not provide evidence on the direct implication of birds in the widespread of Nosema parasites, our finding on the long-distance dispersal of bird flocks between remote breeding colonies adds concern about the role of European bee-eaters in the spread of such disease at a large, inter-continental scale. PMID:26994943

  20. Challenge infection as a means of determining the rate of disease resistant Trichomonas gallinae-free birds in a population

    USGS Publications Warehouse

    Kocan, R.M.; Knisley, J.O.

    1970-01-01

    Trichomonas gallinae-free pigeons and mourning doves were infected with the Jones' Barn strain of T. gallinae to determine the rate of disease resistant T. gallinae-free birds in each population. Although all birds became infected 88% of the pigeons were resistant to trichomoniasis while 82% of the mourning doves were resistant. It was concluded that these birds had been previously infected and spontaneously lost their trichomonad fauna while retaining their resistance to fatal infection.

  1. The early bird gets the shrimp: confronting assumptions of isotopic equilibrium and homogeneity in a wild bird population.

    PubMed

    Wunder, Michael B; Jehl, Joseph R; Stricker, Craig A

    2012-11-01

    1. Because stable isotope distributions in organic material vary systematically across energy gradients that exist in ecosystems, community and population structures, and in individual physiological systems, isotope values in animal tissues have helped address a broad range of questions in animal ecology. It follows that every tissue sample provides an isotopic profile that can be used to study dietary or movement histories of individual animals. Interpretations of these profiles depend on the assumption that metabolic pools are isotopically well mixed and in equilibrium with dietary resources prior to tissue synthesis, and they extend to the population level by assuming isotope profiles are identically distributed for animals using the same proximal dietary resource. As these assumptions are never fully met, studying structure in the variance of tissue isotope values from wild populations is informative. 2. We studied variation in δ(13) C, δ(15) N, δ(2) H and δ(18) O data for feathers from a population of eared grebes (Podiceps nigricollis) that migrate to Great Salt Lake each fall to moult feathers. During this time, they cannot fly and feed almost exclusively on superabundant brine shrimp (Artemia franciscana). The ecological simplicity of this situation minimized the usual spatial and trophic complexities often present in natural studies of feather isotope values. 3. Ranges and variances of isotope values for the feathers were larger than those from previously published studies that report feather isotopic variance, but they were bimodally distributed in all isotope dimensions. Isotope values for proximal dietary resources and local surface water show that some of the feathers we assumed to have been grown locally must have been grown before birds reached isotopic equilibrium with local diet or immediately prior to arrival at Great Salt Lake. 4. Our study provides novel insights about resource use strategies in eared grebes during migration. More generally

  2. The early bird gets the shrimp: Confronting assumptions of isotopic equilibrium and homogeneity in a wild bird population

    USGS Publications Warehouse

    Wunder, Michael B.; Jehl, Joseph R., Jr.; Stricker, Craig A.

    2012-01-01

    1. Because stable isotope distributions in organic material vary systematically across energy gradients that exist in ecosystems, community and population structures, and in individual physiological systems, isotope values in animal tissues have helped address a broad range of questions in animal ecology. It follows that every tissue sample provides an isotopic profile that can be used to study dietary or movement histories of individual animals. Interpretations of these profiles depend on the assumption that metabolic pools are isotopically well mixed and in equilibrium with dietary resources prior to tissue synthesis, and they extend to the population level by assuming isotope profiles are identically distributed for animals using the same proximal dietary resource. As these assumptions are never fully met, studying structure in the variance of tissue isotope values from wild populations is informative. 2. We studied variation in δ13C, δ15N, δ2H and δ18O data for feathers from a population of eared grebes (Podiceps nigricollis) that migrate to Great Salt Lake each fall to moult feathers. During this time, they cannot fly and feed almost exclusively on superabundant brine shrimp (Artemia franciscana). The ecological simplicity of this situation minimized the usual spatial and trophic complexities often present in natural studies of feather isotope values. 3. Ranges and variances of isotope values for the feathers were larger than those from previously published studies that report feather isotopic variance, but they were bimodally distributed in all isotope dimensions. Isotope values for proximal dietary resources and local surface water show that some of the feathers we assumed to have been grown locally must have been grown before birds reached isotopic equilibrium with local diet or immediately prior to arrival at Great Salt Lake. 4. Our study provides novel insights about resource use strategies in eared grebes during migration. More generally, it

  3. POPULATION TRENDS AND EDUCATIONAL CHANGE IN THE STATE OF WASHINGTON.

    ERIC Educational Resources Information Center

    MILLER, VINCENT A.; SCHMID, CALVIN F.

    THE IMPACT OF SOCIAL, ECONOMIC, AND POPULATION CHANGES IN THE STATE OF WASHINGTON WERE ANALYZED TO DETERMINE RELATIONSHIPS TO AND INFLUENCES UPON PUBLIC EDUCATIONAL TRENDS, ESPECIALLY WITH RESPECT TO PHYSICAL FACILITIES, CURRICULUMS, STAFF, FINANCES, AND ADMINISTRATION. FOR THE PURPOSE OF THIS STUDY, THE STATE WAS GROUPED INTO LOGICAL AND…

  4. Breeding Bird Survey and bird banding data: Applications to raptor research and management

    USGS Publications Warehouse

    Sauer, J.R.; Droege, S.; Bystrak, D.

    1991-01-01

    The Breeding Bird Survey (BBS) and Bird Banding Laboratory (BBL) are sources of information for raptor biologists. The BBS has been conducted each year since 1966 in the United States and Canada; historical bird banding records extend back to the early 20th century. BBS data can be used to document population trends and breeding distributions of many bird species. Banding data are generally collected for specific and local studies of bird populations or behavior. Past use of these data has been limited by their volume and relative inaccessibility. In this paper, we present an overview of BBS and BBL raptor data and their uses, limitations and availability.

  5. Regional analysis of population trajectories from the North American Breeding Bird Survey

    USGS Publications Warehouse

    Sauer, J.R.; Link, W.A.

    1999-01-01

    The North American Breeding Bird Survey (BBS) was started in 1966, and provides information on population change and distribution for most of the birds in North America. The geographic extent of the survey, and the logistical compromises needed to survey such a large area, present many challenges for estimation from BBS data. In this paper, we describe the survey and discuss some of the limitations of the survey design and implementation. Analysis of the survey has evolved over time as new statistical methods and insights into the analysis of count data are developed. Survey results and analysis tools for the BBS are now available over intemet; we present new methods that use generalized linear models for estimation of population change and empirical Bayes procedures for regional summaries.

  6. Hierarchical modelling and estimation of abundance and population trends in metapopulation designs.

    PubMed

    Kéry, Marc; Andrew Royle, J

    2010-03-01

    1. Population assessment in changing environments is challenging because factors governing abundance may also affect detectability and thus bias observed counts. We describe a hierarchical modelling framework for estimating abundance corrected for detectability in metapopulation designs, where observations of 'individuals' (e.g. territories) are replicated in space and time. We consider two classes of models; first, we regard the data as independent binomial counts and model abundance and detectability based on a product-binomial likelihood. Secondly, we use the more complex detection-non-detection data for each territory to form encounter history frequencies, and analyse the resulting multinomial/Poisson hierarchical model. Importantly, we extend both models to directly estimate population trends over multiple years. Our models correct for any time trends in detectability when assessing population trends in abundance. 2. We illustrate both models for a farmland and a woodland bird species, skylark Alauda arvensis and willow tit Parus montanus, by applying them to Swiss BBS data, where 268 1 km(2) quadrats were surveyed two to three times during 1999-2003. We fit binomial and multinomial mixture models where log(abundance) depended on year, elevation, forest cover and transect route length, and logit(detection) on year, season and search effort. 3. Parameter estimates were very similar between models with confidence intervals overlapping for most parameters. Trend estimates were similar for skylark (-0.074 +/- 0.041 vs. -0.047 +/- 0.019) and willow tit (0.044 +/- 0.046 vs. 0.047 +/- 0.018). As expected, the multinomial model gave more precise estimates, but also yielded lower abundance estimates for the skylark. This may be due to effects of territory misclassification (lumping error), which do not affect the binomial model. 4. Both models appear useful for estimating abundance and population trends free from distortions by detectability in metapopulation designs

  7. Surveys of forest bird populations found in the vicinity of proposed geothermal project subzones in the district of Puna, Hawaii

    SciTech Connect

    Jacobi, J.D.; Reynolds, M.; Ritchotte, G.; Nielsen, B.; Viggiano, A.; Dwyer, J.

    1994-10-01

    This report presents data on the distribution and status of forest bird species found within the vicinity of proposed geothermal resource development on the Island of Hawaii. Potential impacts of the proposed development on the native bird populations found in the project are are addressed.

  8. Population dynamics of neotropical migratory birds using agriculture-forest mosaics in Campeche, Mexico

    USGS Publications Warehouse

    Wilson, M.H.; Berlanga, M.; Dawson, D.; Wood, P.; Sauer, J.; Robbins, C.S.

    1995-01-01

    In many areas of the tropics, forests are being converted to agriculture and other uses at a rapid rate. Previous research has documented that forest-breeding migratory birds are distributed across a wide variety of habitat types during midwinter. However, to evaluate the relative importance of different habitat types to wintering birds, we need to examine habitat-specific estimates of survival. During the winter of 1992-1993, mist nets, observations of individually marked birds and point counts were used to sample bird populations in a pasture-forest mosaic in southern Mexico. Sampling was conducted four times throughout the winter on a total of six grids. Twenty nets were run for two days in each grid. A total of 129 species were captured and 3,585 individuals banded. Neotropical migrants made up 31% of the species captured and 47% of the individuals banded. The banding data were used to estimate species richness for permanent and winter residents in different habitats and at different time periods. Capture-recapture models were used to estimate overwintering survival for selected species.

  9. Model to Track Wild Birds for Avian Influenza by Means of Population Dynamics and Surveillance Information

    PubMed Central

    Alba, Anna; Bicout, Dominique J.; Vidal, Francesc; Curcó, Antoni; Allepuz, Alberto; Napp, Sebastián; García-Bocanegra, Ignacio; Costa, Taiana; Casal, Jordi

    2012-01-01

    Design, sampling and data interpretation constitute an important challenge for wildlife surveillance of avian influenza viruses (AIV). The aim of this study was to construct a model to improve and enhance identification in both different periods and locations of avian species likely at high risk of contact with AIV in a specific wetland. This study presents an individual-based stochastic model for the Ebre Delta as an example of this appliance. Based on the Monte-Carlo method, the model simulates the dynamics of the spread of AIV among wild birds in a natural park following introduction of an infected bird. Data on wild bird species population, apparent AIV prevalence recorded in wild birds during the period of study, and ecological information on factors such as behaviour, contact rates or patterns of movements of waterfowl were incorporated as inputs of the model. From these inputs, the model predicted those species that would introduce most of AIV in different periods and those species and areas that would be at high risk as a consequence of the spread of these AIV incursions. This method can serve as a complementary tool to previous studies to optimize the allocation of the limited AI surveillance resources in a local complex ecosystem. However, this study indicates that in order to predict the evolution of the spread of AIV at the local scale, there is a need for further research on the identification of host factors involved in the interspecies transmission of AIV. PMID:22952962

  10. Genetic population structure and call variation in a passerine bird, the satin bowerbird, Ptilonorhynchus violaceus.

    PubMed

    Nicholls, J A; Austin, J J; Moritz, C; Goldizen, A W

    2006-06-01

    Geographic variation in vocalizations is widespread in passerine birds, but its origins and maintenance remain unclear. One hypothesis to explain this variation is that it is associated with geographic isolation among populations and therefore should follow a vicariant pattern similar to that typically found in neutral genetic markers. Alternatively, if environmental selection strongly influences vocalizations, then genetic divergence and vocal divergence may be disassociated. This study compared genetic divergence derived from 11 microsatellite markers with a metric of phenotypic divergence derived from male bower advertisement calls. Data were obtained from 16 populations throughout the entire distribution of the satin bowerbird, an Australian wet-forest-restricted passerine. There was no relationship between call divergence and genetic divergence, similar to most other studies on birds with learned vocalizations. Genetic divergence followed a vicariant model of evolution, with the differentiation of isolated populations and isolation-by-distance among continuous populations. Previous work on Ptilonorhynchus violaceus has shown that advertisement call structure is strongly influenced by the acoustic environment of different habitats. Divergence in vocalizations among genetically related populations in different habitats indicates that satin bowerbirds match their vocalizations to the environment in which they live, despite the homogenizing influence of gene flow. In combination with convergence of vocalizations among genetically divergent populations occurring in the same habitat, this shows the overriding importance that habitat-related selection can have on the establishment and maintenance of variation in vocalizations. PMID:16892977

  11. Birds, Birds, Birds!

    ERIC Educational Resources Information Center

    Braus, Judy, Ed.

    1992-01-01

    Ranger Rick's Nature Scope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. Contents are organized into the following sections: (1) "What Makes a Bird a Bird?," which provides…

  12. Estimation of Coast-Wide Population Trends of Marbled Murrelets in Canada Using a Bayesian Hierarchical Model.

    PubMed

    Bertram, Douglas F; Drever, Mark C; McAllister, Murdoch K; Schroeder, Bernard K; Lindsay, David J; Faust, Deborah A

    2015-01-01

    Species at risk with secretive breeding behaviours, low densities, and wide geographic range pose a significant challenge to conservation actions because population trends are difficult to detect. Such is the case with the Marbled Murrelet (Brachyramphus marmoratus), a seabird listed as 'Threatened' by the Species at Risk Act in Canada largely due to the loss of its old growth forest nesting habitat. We report the first estimates of population trend of Marbled Murrelets in Canada derived from a monitoring program that uses marine radar to detect birds as they enter forest watersheds during 923 dawn surveys at 58 radar monitoring stations within the six Marbled Murrelet Conservation Regions on coastal British Columbia, Canada, 1996-2013. Temporal trends in radar counts were analyzed with a hierarchical Bayesian multivariate modeling approach that controlled for variation in tilt of the radar unit and day of year, included year-specific deviations from the overall trend ('year effects'), and allowed for trends to be estimated at three spatial scales. A negative overall trend of -1.6%/yr (95% credibility interval: -3.2%, 0.01%) indicated moderate evidence for a coast-wide decline, although trends varied strongly among the six conservation regions. Negative annual trends were detected in East Vancouver Island (-9%/yr) and South Mainland Coast (-3%/yr) Conservation Regions. Over a quarter of the year effects were significantly different from zero, and the estimated standard deviation in common-shared year effects between sites within each region was about 50% per year. This large common-shared interannual variation in counts may have been caused by regional movements of birds related to changes in marine conditions that affect the availability of prey. PMID:26258803

  13. Estimation of Coast-Wide Population Trends of Marbled Murrelets in Canada Using a Bayesian Hierarchical Model

    PubMed Central

    Schroeder, Bernard K.; Lindsay, David J.; Faust, Deborah A.

    2015-01-01

    Species at risk with secretive breeding behaviours, low densities, and wide geographic range pose a significant challenge to conservation actions because population trends are difficult to detect. Such is the case with the Marbled Murrelet (Brachyramphus marmoratus), a seabird listed as ‘Threatened’ by the Species at Risk Act in Canada largely due to the loss of its old growth forest nesting habitat. We report the first estimates of population trend of Marbled Murrelets in Canada derived from a monitoring program that uses marine radar to detect birds as they enter forest watersheds during 923 dawn surveys at 58 radar monitoring stations within the six Marbled Murrelet Conservation Regions on coastal British Columbia, Canada, 1996–2013. Temporal trends in radar counts were analyzed with a hierarchical Bayesian multivariate modeling approach that controlled for variation in tilt of the radar unit and day of year, included year-specific deviations from the overall trend (‘year effects’), and allowed for trends to be estimated at three spatial scales. A negative overall trend of -1.6%/yr (95% credibility interval: -3.2%, 0.01%) indicated moderate evidence for a coast-wide decline, although trends varied strongly among the six conservation regions. Negative annual trends were detected in East Vancouver Island (-9%/yr) and South Mainland Coast (-3%/yr) Conservation Regions. Over a quarter of the year effects were significantly different from zero, and the estimated standard deviation in common-shared year effects between sites within each region was about 50% per year. This large common-shared interannual variation in counts may have been caused by regional movements of birds related to changes in marine conditions that affect the availability of prey. PMID:26258803

  14. No Association between Personality and Candidate Gene Polymorphisms in a Wild Bird Population

    PubMed Central

    Durieux, Gillian; Burke, Terry; Dugdale, Hannah L.

    2015-01-01

    Consistency of between-individual differences in behaviour or personality is a phenomenon in populations that can have ecological consequences and evolutionary potential. One way that behaviour can evolve is to have a genetic basis. Identifying the molecular genetic basis of personality could therefore provide insight into how and why such variation is maintained, particularly in natural populations. Previously identified candidate genes for personality in birds include the dopamine receptor D4 (DRD4), and serotonin transporter (SERT). Studies of wild bird populations have shown that exploratory and bold behaviours are associated with polymorphisms in both DRD4 and SERT. Here we tested for polymorphisms in DRD4 and SERT in the Seychelles warbler (Acrocephalus sechellensis) population on Cousin Island, Seychelles, and then investigated correlations between personality and polymorphisms in these genes. We found no genetic variation in DRD4, but identified four polymorphisms in SERT that clustered into five haplotypes. There was no correlation between bold or exploratory behaviours and SERT polymorphisms/haplotypes. The null result was not due to lack of power, and indicates that there was no association between these behaviours and variation in the candidate genes tested in this population. These null findings provide important data to facilitate representative future meta-analyses on candidate personality genes. PMID:26473495

  15. Migratory bird hunter opinions regarding potential management strategies for controlling light goose populations

    USGS Publications Warehouse

    Dinges, Andrew J.; Webb, Elisabeth B.; Vrtiska, Mark P.; Nilon, Charles H.; Wilhelm Stanis, Sonja A.

    2014-01-01

    We expanded the Nebraska Light Goose Conservation Order (LGCO) harvest survey (NE, USA) in spring 2012 to assess migratory bird hunter opinions regarding future management strategies for controlling light goose populations. Although hunters strongly agreed that population control of light geese was an important wildlife management issue, they were generally unsupportive of wildlife officials using forms of direct control methods to control light goose populations. Respondents who indicated participation in the 2012 LGCO were also less supportive of any form of direct control compared with migratory bird hunters who did not participate in the LGCO. When presented with alternative methods by wildlife officials for future light goose population control, respondents were most supportive of wildlife agencies selectively shooting light geese on migration and wintering areas and least supportive of wildlife officials using bait with approved chemicals to euthanize light geese. A clear understanding of public perception of various potential direct-control options will likely assist wildlife biologists in making informed decisions on how to proceed with population control of light geese.

  16. Rural and Nonmetropolitan Population Trends of Significance to National Population Policy.

    ERIC Educational Resources Information Center

    Beale, Calvin L.

    The purpose of this paper is to review recent trends in the rural and/or nonmetropolitan population and to indicate some of the linkages and implications for national population policy. The vast rural to urban migration of the last generation was necessary and rational, since most migrants believed they benefitted by moving. Although much of the…

  17. Assessment of bird populations in a high quality savanna/woodland: a banding approach

    USGS Publications Warehouse

    Wilmore, Sandra L.; Glowacki, Gary A.; Grundel, Ralph

    2005-01-01

    During the course of this six year study, the fall migration capture rate declined significantly, suggesting that reduced productivity may have occurred in bird populations. There was a positive response during the spring migration to earlier spring wildfires, indicated by high capture rates in 2000 and 2002 that corresponded with fires affecting most of the bird banding net locations. For several common species found at the Miller Woods site, the ratio of juveniles to adults was compared to ratios at other banding stations in the north central U.S. Breeding site fidelity was documented for 20 species, all common breeders. Variation in capture rates among net locations demonstrated the role of the shrub layer within the savanna habitat mosaic during migration stopover.

  18. Relationships between nesting populations of wading birds and wetland habitat features

    USGS Publications Warehouse

    Erwin, R.M.; Spendelow, J.A.; Geissler, P.H.; Williams, B.K.

    1986-01-01

    We used data from censuses of wading bird colonies on the Atlantic coast from Maine to Florida {1976-1977) to examine relationships between population sizes of wading birds {herons, egrets, ibises) and 9 key habitat features. Variables included features of the colony site {island size, dimensions, isolation from adjacent land) and surrounding (5 km circle) potential feeding habitat {wetland area). Measurements were made on nautical charts using a planimeter. For 122 colonies on islands, 5 multivariate procedures were used. Because of high correlations among habitat variables, a reduced regression model using only 4 variables performed best. The only variable that approached statistical significance (P = 0.06) was land-water interface distance (i.e., wetland 'edge' within the 5 km circle centered on the colony site).

  19. Population declines in North American birds that migrate to the neotropics

    USGS Publications Warehouse

    Robbins, C.S.; Sauer, J.R.; Greenberg, R.S.; Droege, S.

    1989-01-01

    Using data from the North American Breeding Bird Survey, we determined that most neotropical migrant bird species that breed in forests of the eastern United States and Canada have recently (1978-1987) declined in abundance after a period of stable or increasing populations. Most permanent residents and temperate-zone migrants did not show a general pattern of decrease during this period. Field data from Mexico were used to classify a subset of the neotropical migrants as using forest or scrub habitats during winter. Population declines during 1978-1987 were significantly greater among the forest-wintering species, while populations of scrub-wintering species increased. The same subset of neotropical migrants also showed overall declines in forest-breeding species, but no significant differences existed between species breeding in forest and scrub habitats. Neotropical migrant species that primarily use forested habitats in either wintering or breeding areas are declining, but a statistically significant association between habitat and population declines was detected only in the tropics.

  20. Older driver population and crash involvement trends, 1974-1988.

    PubMed

    Stutts, J C; Martell, C

    1992-08-01

    North Carolina motor vehicle crash data for even-numbered years 1974-1988, inclusive, are analyzed in conjunction with North Carolina population, licensed driver, and mileage data to examine trends in motor vehicle crash involvement by driver age, sex, and race. Crash rates per licensed driver are presented along with crash rates per estimated vehicle miles travelled calculated on the basis of induced exposure. Results focus particularly on older drivers. They show that older drivers' representation in the licensed driver population has increased at a greater rate than their representation in either the census or crash involvement populations. These trends are particularly strong for females and for nonwhites. Furthermore, crash rates have declined more for drivers aged 55 and older than for younger drivers. The greatest declines, both in terms of crashes per licensed driver and crashes per estimated miles travelled, have been experienced by drivers age 65 and older, particularly nonwhites. Males show higher overall crash rates per miles travelled than females, but this effect decreases with age and disappears entirely in the oldest age categories. Results are discussed in light of the changing nature of the overall driving population and the cohort of older drivers in particular. PMID:1605814

  1. Brominated flame retardant trends in aquatic birds from the Salish Sea region of the west coast of North America, including a mini-review of recent trends in marine and estuarine birds.

    PubMed

    Miller, Aroha; Elliott, John E; Elliott, Kyle H; Guigueno, Mélanie F; Wilson, Laurie K; Lee, Sandi; Idrissi, Abde

    2015-01-01

    Polybrominated diphenyl ethers (PBDEs) increased in many matrices during the 1990s and early 2000s. Since voluntary restrictions and regulations on PBDEs were implemented in North America circa early 2000s, decreases in PBDEs have occurred in many of these same matrices. To examine temporal trends in the North Pacific, we retrospectively analysed PBDEs and eight non-PBDE flame retardants (FR) in eggs of two aquatic bird species, great blue herons, Ardea herodias, and double-crested cormorants, Phalacrocorax auritus, collected along the British Columbia coast, Canada from 1979 to 2012. Increasing PBDE concentrations were observed in both species followed by significant decreases post-2000 for all dominant congeners and ΣPBDE. Non-PBDE FRs were generally undetected in cormorant eggs, or detected at very low levels in heron eggs, except for hexabromocyclododecane (HBCDD). HBCDD, currently unregulated in North America, was not detected in early sampling years; however low concentrations were observed in both species in recent sampling years (2003-2012). Dietary tracers (δ(13)C and δ(15)N) did not change significantly over time, indicating that temporal changes in PBDEs are likely caused by implemented regulations. A comparison with recently published temporal trends of ΣPBDE in marine birds from North America and Europe is given. PMID:25241209

  2. Evaluation of population-level ecological risks of dioxin-like polychlorinated biphenyl exposure to fish-eating birds in Tokyo Bay and its vicinity.

    PubMed

    Naito, Wataru; Murata, Mariko

    2007-01-01

    Population-level assessments of the ecological risks of dioxin-like polychlorinated biphenyl (PCB) exposure to fish-eating birds in Tokyo Bay and its vicinity were performed to judge the need for risk management measures to protect aquatic wildlife from dioxin-like PCB contamination. Egg mortality risk and changes in the population growth rate (lambda) in relation to the contamination levels of dioxin-like PCBs in eggs of gray heron (Ardea cinerea), great cormorant (Phalacrocorax carbo), osprey (Pandion halieaetus), and kingfisher (Alcedo atthis) were determined by integrating the results of exposure analysis, effect analysis, and a life-history model for each species. The egg mortality risks for the gray heron, great cormorant, osprey, and kingfisher populations were calculated to be 5.8, 6.8, 12, and less than 1%, respectively. The estimated lambda for those populations were calculated to be 1.061, 1.405, 1.024, and 1.131, respectively. The percentage changes in lambda for those populations were estimated to be 1.2, 2.0, 1.6, and less than 1%, respectively. Our results implied that the levels of dioxin-like PCBs observed in the Tokyo Bay area alone would not have significant population-level effects on the fish-eating bird populations. It is concluded that along with the trend toward decreasing dioxin and dioxin-like PCB levels in Tokyo Bay, no urgent need exists for risk-reduction measures to protect fish-eating bird populations against dioxin-like PCBs. PMID:17283596

  3. Dynamics of low and high pathogenic avian influenza in wild and domestic bird populations.

    PubMed

    Tuncer, Necibe; Torres, Juan; Martcheva, Maia; Barfield, Michael; Holt, Robert D

    2016-01-01

    This paper introduces a time-since-recovery structured, multi-strain, multi-population model of avian influenza. Influenza A viruses infect many species of wild and domestic birds and are classified into two groups based on their ability to cause disease: low pathogenic avian influenza (LPAI) and high pathogenic avian influenza (HPAI). Prior infection with LPAI provides partial immunity towards HPAI. The model introduced in this paper structures LPAI-recovered birds (wild and domestic) with time-since-recovery and includes cross-immunity towards HPAI that can fade with time. The model has a unique disease-free equilibrium (DFE), unique LPAI-only and HPAI-only equilibria and at least one coexistence equilibrium. We compute the reproduction numbers of LPAI ([Formula: see text]) and HPAI ([Formula: see text]) and show that the DFE is locally asymptotically stable when [Formula: see text] and [Formula: see text]. A unique LPAI-only (HPAI-only) equilibrium exists when [Formula: see text] ([Formula: see text]) and it is locally asymptotically stable if HPAI (LPAI) cannot invade the equilibrium, that is, if the invasion number [Formula: see text] ([Formula: see text]). We show using numerical simulations that the ODE version of the model, which is obtained by discarding the time-since-recovery structures (making cross-immunity constant), can exhibit oscillations, and also that the pathogens LPAI and HPAI can coexist with sustained oscillations in both populations. Through simulations, we show that even if both populations (wild and domestic) are sinks when alone, LPAI and HPAI can persist in both populations combined. Thus, reducing the reproduction numbers of LPAI and HPAI in each population to below unity is not enough to eradicate the disease. The pathogens can continue to coexist in both populations unless transmission between the populations is reduced. PMID:26667351

  4. Population trends of spanwise vortices in wall turbulence

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Christensen, K. T.

    2006-12-01

    The present effort documents the population trends of prograde and retrograde spanwise vortex cores in wall turbulence outside the buffer layer. Large ensembles of instantaneous velocity fields are acquired by particle-image velocimetry in the streamwise wall-normal plane of both turbulent channel flow at Re_tauequiv u_*delta/nu=570, 1185 and 1760 and a zero-pressure-gradient turbulent boundary layer at Re_tau=1400, 2350 and 3450. Substantial numbers of prograde spanwise vortices are found to populate the inner boundary of the log layer of both flows and most of these vortices have structural signatures consistent with the heads of hairpin vortices. In contrast, retrograde vortices are most prominent at the outer edge of the log layer, often nesting near clusters of prograde vortices. Appropriate Reynolds-number scalings for outer- and inner-scaled population densities of prograde and retrograde vortices are determined. However, the Re_tau=570 channel-flow case deviates from these scalings, indicating that it suffers from low-Re effects. When the population densities are recast in terms of fractions of resolved prograde and retrograde spanwise vortices, similarity is observed for 100 {<} y(+ {<} 0.8delta^+) in channel flow and in both flows for 100 {<} y(+ {<} 0.3delta^+) over the Re_tau range studied. The fraction of retrograde vortices increases slightly with Re_tau beyond the log layer in both flows, suggesting that they may play an increasingly important role at higher Reynolds numbers. Finally, while the overall prograde and retrograde population trends of channel flow and the boundary layer show little difference for y {<} 0.45delta, the retrograde populations differ considerably beyond this point, highlighting the influence of the opposing wall in channel flow.

  5. Experimental evaluation of population trend and harvest composition in a Wyoming cougar population

    USGS Publications Warehouse

    Anderson, C.R., Jr.; Lindzey, F.G.

    2005-01-01

    Cougar (Puma concolor) management has been hindered by inability to identify population trends. We documented changes in sex and age of harvested cougars during an experimentally induced reduction in population size and subsequent recovery to better understand the relationship between sex-age composition and population trend in exploited populations. The cougar population in the Snowy Range, southeast Wyoming, was reduced by increased harvest (treatment phase) from 58 independent cougars (>1 year old) (90% CI = 36-81) in the autumn of 1998 to 20 by the spring of 2000 (mean exploitation rate = 43%) and then increased to 46 by spring 2003 following 3 years of reduced harvests (mean exploitation rate = 18%). Pretreatment harvest composition was 63% subadults (1.0-2.5 years old), 23% adult males, and 14% adult females (2 seasons; n = 22). A reduction in subadult harvest, an initial increase followed by a reduction in adult male harvest, and a steady increase in adult female harvest characterized harvest composition trends during the treatment phase. Harvest composition was similar at high and low densities when harvest was light, but proportion of harvested subadult males increased at low density as they replaced adult males removed during the treatment period (high harvest). While sex ratio of harvested cougars alone appears of limited value in identifying population change, when combined with age class the 2 appear to provide an index to population change. Composition of the harvest can be applied to adaptively manage cougar populations where adequate sex and age data are collected from harvested animals.

  6. Observer differences in the North American Breeding Bird Survey

    USGS Publications Warehouse

    Sauer, J.R.; Peterjohn, B.G.; Link, W.A.

    1994-01-01

    Because count data collected in many bird surveys are only an index to population size, factors that can influence the counts must be identified and incorporated into analyses. Observer quality is often ignored in analyses of population changes from survey data, but observers differ in methods and capabilities and, hence, tend to count different numbers of birds. We assess the consequences of between-observer differences in counts for estimation of population trends in the North American Breeding Bird Survey. Observer differences in numbers of birds counted were found in 50% of the 369 species we examined. For many species, observers in later years tended to count more birds than observers in earlier years, suggesting an increase in observer quality over time. Analysis of population trends from 1966 through 1991 indicates that failure to include observers as covariables in the analysis results in an overly optimistic view of population trends.

  7. [Urbanization mechanisms in bird species: population systems transformations or adaptations at the individual level?].

    PubMed

    Fridman, V S; Eremkin, G S; Zakharova-Kubareva, N Iu

    2008-01-01

    The present research deals with urbanization of wild bird and mammal species. Forms and mechanisms of population steadiness in the urban landscape have been examined. The urbanization process turned out to be a directed change of the population system forming de novo in the urbolandscape leading to a sustainable organization peculiar for the particular environment. The population organization of different types in urbolandscape is found to provide its stability under conditions of directed and fast changes accompanied with instability and heterogenous structure of habitats. It is shown that the same type of population organization meets the corresponding demands among different species settling in the urban environment. Its features are "openness" and "flowage" of the groups, far order of settlement levels and other units of population system, constant movements of the individuals between the groups as a respond to the signals of urboenvironment significant changes. The "urban" variant of the population system organization turns out to be opposite to that of the same species in the non-urban habitats. After formation of the urban types by the species and successful developing of the town, the urban population becomes separated from the maternal local population and begins to exist independently in the urban landscape. The variety of adaptation aberrations in ecology, behavior, and mode of life of urban birds is the population system stability function in the urban landscape and is not a results of individual selection. It is shown that the urbanization process of the species goes firstly on the population level being the system structure transformation developed by the species towards the most stable state in the town (city) territory. Only after the appearance of stable urban population, the urban individuals show the rapid growth of different changes in ecology, behavior, mode of life that was traditionally described by naturalists as species adaptation to the

  8. Changes in size and trends of North American sea duck populations associated with North Pacific oceanic regime shifts

    USGS Publications Warehouse

    Flint, Paul L.

    2013-01-01

    Broad-scale multi-species declines in populations of North American sea ducks for unknown reasons is cause for management concern. Oceanic regime shifts have been associated with rapid changes in ecosystem structure of the North Pacific and Bering Sea. However, relatively little is known about potential effects of these changes in oceanic conditions on marine bird populations at broad scales. I examined changes in North American breeding populations of sea ducks from 1957 to 2011 in relation to potential oceanic regime shifts in the North Pacific in 1977, 1989, and 1998. There was strong support for population-level effects of regime shifts in 1977 and 1989, but little support for an effect of the 1998 shift. The continental-level effects of these regime shifts differed across species groups and time. Based on patterns of sea duck population dynamics associated with regime shifts, it is unclear if the mechanism of change relates to survival or reproduction. Results of this analysis support the hypothesis that population size and trends of North American sea ducks are strongly influenced by oceanic conditions. The perceived population declines appear to have halted >20 years ago, and populations have been relatively stable or increasing since that time. Given these results, we should reasonably expect dramatic changes in sea duck population status and trends with future oceanic regime shifts.

  9. Z chromosome divergence, polymorphism and relative effective population size in a genus of lekking birds.

    PubMed

    Oyler-McCance, S J; Cornman, R S; Jones, K L; Fike, J A

    2015-11-01

    Sex chromosomes contribute disproportionately to species boundaries as they diverge faster than autosomes and often have reduced diversity. Their hemizygous nature contributes to faster divergence and reduced diversity, as do some types of selection. In birds, other factors (mating system and bottlenecks) can further decrease the effective population size of Z-linked loci and accelerate divergence (Fast-Z). We assessed Z-linked divergence and effective population sizes for two polygynous sage-grouse species and compared them to estimates from birds with various mating systems. We found lower diversity and higher FST for Z-linked loci than for autosomes, as expected. The π(Z)/π(A) ratio was 0.38 in Centrocercus minimus, 0.48 in Centrocercus urophasianus and 0.59 in a diverged, parapatric population of C. urophasianus, a broad range given the mating system among these groups is presumably equivalent. The full data set had unequal males and females across groups, so we compared an equally balanced reduced set of C. minimus and individuals pooled from both C. urophasianus subgroups recovering similar estimates: 0.54 for C. urophasianus and 0.38 for C. minimus. We provide further evidence that N(eZ)/N(eA) in birds is often lower than expected under random mating or monogamy. The lower ratio in C. minimus could be a consequence of stronger selection or drift acting on Z loci during speciation, as this species differs strongly from C. urophasianus in sexually selected characters with minimal mitochondrial divergence. As C. minimus also exhibited lower genomic diversity, it is possible that a more severe demographic history may contribute to its lower ratio. PMID:26014526

  10. Z chromosome divergence, polymorphism and relative effective population size in a genus of lekking birds

    USGS Publications Warehouse

    Oyler-McCance, Sara J.; Cornman, Robert S.; Kenneth L. Jones; Fike, Jennifer

    2015-01-01

    Sex chromosomes contribute disproportionately to species boundaries as they diverge faster than autosomes and often have reduced diversity. Their hemizygous nature contributes to faster divergence and reduced diversity, as do some types of selection. In birds, other factors (mating system and bottlenecks) can further decrease the effective population size of Z-linked loci and accelerate divergence (Fast-Z). We assessed Z-linked divergence and effective population sizes for two polygynous sage-grouse species and compared them to estimates from birds with various mating systems. We found lower diversity and higher FST for Z-linked loci than for autosomes, as expected. The πZ/πA ratio was 0.38 in Centrocercus minimus, 0.48 in Centrocercus urophasianus and 0.59 in a diverged, parapatric population of C. urophasianus, a broad range given the mating system among these groups is presumably equivalent. The full data set had unequal males and females across groups, so we compared an equally balanced reduced set of C. minimus and individuals pooled from both C. urophasianus subgroups recovering similar estimates: 0.54 for C. urophasianus and 0.38 for C. minimus. We provide further evidence that NeZ/NeA in birds is often lower than expected under random mating or monogamy. The lower ratio in C. minimus could be a consequence of stronger selection or drift acting on Z loci during speciation, as this species differs strongly from C. urophasianus in sexually selected characters with minimal mitochondrial divergence. As C. minimus also exhibited lower genomic diversity, it is possible that a more severe demographic history may contribute to its lower ratio.

  11. Extra-pair paternity in birds: explaining variation between species and populations.

    PubMed

    Petrie, M; Kempenaers, B

    1998-02-01

    Molecular techniques used to assign paternity have revealed previously unknown incidences of extra-pair paternity in socially monogamous bird species. DNA fingerprinting has now been used sufficiently often for mating-system biologists to appreciate the natural variation in the frequency of broods showing extra-pair young. The variation between species and between populations of the same species is surprisingly marked. Explaining this variation may help us to understand the factors promoting sexual selection. Recent comparative studies and detailed behavioural studies suggest that factors such as breeding density, genetic variation in the population and the intensity of sexual conflicts determine the costs and benefits to males and females of engaging in extra-pair copulations, and therefore contribute to the variation among populations. PMID:21238200

  12. Population pressure on coral atolls: trends and approaching limits.

    PubMed

    Rapaport, M

    1990-09-01

    Trends and approaching limits of population pressure on coral atolls is discussed by examining the atoll environment in terms of the physical geography, the production systems, and resource distribution. Atoll populations are grouped as dependent and independent, and demographic trends in population growth, migraiton, urbanization, and political dependency are reviewed. Examination of the carrying capacity includes a dynamic model, the influences of the West, and philopsophical considerations. The carrying capacity is the "maximal population supportable in a given area". Traditional models are criticized because of a lack in accounting for external linkages. The proposed model is dynamic and considers perceived needs and overseas linkages. It also explains regional disparities in population distribution, and provides a continuing model for population movement from outer islands to district centers and mainland areas. Because of increased expectations and perceived needs, there is a lower carrying capacity for outlying areas, and expanded capacity in district centers. This leads to urbanization, emigration, and carrying capacity overshot in regional and mainland areas. Policy intervention is necessary at the regional and island community level. Atolls, which are islands surrounding deep lagoons, exist in archipelagoes across the oceans, and are rich in aquatic life. The balance in this small land area with a vulnerable ecosystem may be easily disturbed by scarce water supplies, barren soils, rising sea levels in the future, hurricanes, and tsunamis. Traditionally, fisheries and horticulture (pit-taro, coconuts, and breadfruit) have sustained populations, but modern influences such as blasting, reef mining, new industrial technologies, population pressure, and urbanization threaten the balance. Population pressure, which has lead to pollution, epidemics, malnutrition, crime, social disintegration, and foreign dependence, is evidenced in the areas of Tuvalu, Kiribati

  13. Abundance-area relationships in bird assemblages along an Afrotropical elevational gradient: space limitation in montane forest selects for higher population densities.

    PubMed

    Ferenc, Michal; Fjeldså, Jon; Sedláček, Ondřej; Motombi, Francis Njie; Djomo Nana, Eric; Mudrová, Karolína; Hořák, David

    2016-05-01

    The usual positive inter-specific relationship between range size and abundance of local populations can have notable exceptions in Afrotropical montane areas, where range-restricted bird species are unusually abundant. We tested how the area occupied locally by passerines and their geographic range size relate to local abundances along a tropical elevational gradient of Mt Cameroon, West-Central Africa. Data on bird assemblages were collected at six forested elevations (350, 650, 1100, 1500, 1850 m, 2200 m a.s.l.) using a standardised point count at 16 locations per elevation. Elevational ranges of birds were compiled from published sources and their geographic range sizes were determined as the occupancy of 1° x 1° grid cells. The observed relationship between local abundance and geographic range size within the entire passerine assemblage on Mt Cameroon disagrees with the most frequently reported positive pattern. However, the patterns differ among elevations, with positive trends of the abundance-range size relationship in lowland changing to negative trends towards higher elevations. Interestingly, the total assemblage abundances do not differ much among elevations and population size estimates of species occupying different parts of the gradient remain relatively constant. These patterns are caused by relatively high abundances of montane species, which might be a result of long-term ecological specialization and/or competitive release in species-poor montane locations and possibly facilitated by an extinction filter. Our data suggest that montane species' abilities to maintain dense populations might compensate for less area available near mountain tops and help these populations to circumvent extinction. PMID:26801494

  14. How a trend towards a stationary population affects consumer demand.

    PubMed

    Espenshade, T J

    1978-03-01

    Abstract During the great depression of the 1930seconomists in both the United States and Europe tried to analyse the economic consequences of declining rates of population growth. Not only were birth rates in many industrial countries at the lowest levels ever, but they coincided with high rates of unemployment. Of the many economists who held that demographic trends were partly responsible for the adverse economic conditions, a prominent example was John Maynard Keynes. According to his so-called stagnation thesis, population growth stimulates investment demand in two ways: more people need more goods and services and, hence, more investment in factories and machinery; and with population growing, businessmen are more likely to regard their investment misallocations as less serious than when the growth is slow or nil.(1)A minority of writers were more optimistic about the economic consequences of slower rates of population growth. For example, Thompson argued that with a lower ratio of consumers to producers the population would enjoy a higher standard of living and the education of children should improve.(2). PMID:22091937

  15. Are southern California's fragmented saltmarshes capable of sustaining endemic bird populations?

    USGS Publications Warehouse

    Powell, A.N.

    2006-01-01

    Loss of coastal saltmarshes in southern California has been estimated at 75-90% since presettlement times. The remaining wetlands are mostly fragmented and degraded, and most frequently have harsh edges adjacent to urban landscapes. Non-migratory Belding's Savannah Sparrows (Passerculus sandwichensis beldingi) and Light-footed Clapper Rails (Rallus longirostris levipes) are endemic to saltmarshes in southern California and Baja California, Mexico. Population sizes of Belding's Savannah Sparrows show a positive relationship with saltmarsh area, but few large wetland fragments remain within their range in California. Belding's Savannah Sparrows are sensitive to fragmentation and isolation, with small isolated marshes acting as population sinks. In addition, this subspecies shows low genetic variability, limited dispersal, and small effective population sizes. Light-footed Clapper Rails are habitat specialists, found in marshes with good tidal flushing that support California cordgrass (Spartina foliosa) habitats. Light-footed Clapper rails also show low genetic variability and limited dispersal and the remnant populations of clapper rails are relatively isolated from one another. Large wetland complexes may serve as population sources for both species, while small, isolated marshes may act as population sinks but more research is needed to estimate and model the dynamics of these two metapopulations. Mitigation for wetland loss and restoration projects should not be evaluated simply by presence of rare bird species alone, but instead efforts should be made to determine population sustainability.

  16. Strategic Grassland Bird Conservation throughout the annual cycle: Linking policy alternatives, landowner decisions, and biological population outcomes

    USGS Publications Warehouse

    Drum, Ryan G.; Ribic, Christine; Koch, Katie; Lonsdorf, Eric V.; Grant, Edward C.; Ahlering, Marissa; Barnhill, Laurel; Dailey, Thomas; Lor, Socheata; Mueller, Connie; Pavlacky, D.C., Jr.; Rideout, Catherine; Sample, David W.

    2015-01-01

    Grassland bird habitat has declined substantially in the United States. Remaining grasslands are increasingly fragmented, mostly privately owned, and vary greatly in terms of habitat quality and protection status. A coordinated strategic response for grassland bird conservation is difficult, largely due to the scope and complexity of the problem, further compounded by biological, sociological, and economic uncertainties. We describe the results from a collaborative Structured Decision Making (SDM) workshop focused on linking social and economic drivers of landscape change to grassland bird population outcomes. We identified and evaluated alternative strategies for grassland bird conservation using a series of rapid prototype models. We modeled change in grassland and agriculture cover in hypothetical landscapes resulting from different landowner decisions in response to alternative socio-economic conservation policy decisions. Resulting changes in land cover at all three stages of the annual cycle (breeding, wintering, and migration) were used to estimate changes in grassland bird populations. Our results suggest that successful grassland bird conservation may depend upon linkages with ecosystem services on working agricultural lands and grassland-based marketing campaigns to engage the public. With further development, spatial models that link landowner decisions with biological outcomes can be essential tools for making conservation policy decisions. A coordinated non-traditional partnership will likely be necessary to clearly understand and systematically respond to the many conservation challenges facing grassland birds.

  17. Strategic Grassland Bird Conservation throughout the Annual Cycle: Linking Policy Alternatives, Landowner Decisions, and Biological Population Outcomes

    PubMed Central

    Drum, Ryan G.; Ribic, Christine A.; Koch, Katie; Lonsdorf, Eric; Grant, Evan; Ahlering, Marissa; Barnhill, Laurel; Dailey, Thomas; Lor, Socheata; Mueller, Connie; Pavlacky, David C.; Rideout, Catherine; Sample, David

    2015-01-01

    Grassland bird habitat has declined substantially in the United States. Remaining grasslands are increasingly fragmented, mostly privately owned, and vary greatly in terms of habitat quality and protection status. A coordinated strategic response for grassland bird conservation is difficult, largely due to the scope and complexity of the problem, further compounded by biological, sociological, and economic uncertainties. We describe the results from a collaborative Structured Decision Making (SDM) workshop focused on linking social and economic drivers of landscape change to grassland bird population outcomes. We identified and evaluated alternative strategies for grassland bird conservation using a series of rapid prototype models. We modeled change in grassland and agriculture cover in hypothetical landscapes resulting from different landowner decisions in response to alternative socio-economic conservation policy decisions. Resulting changes in land cover at all three stages of the annual cycle (breeding, wintering, and migration) were used to estimate changes in grassland bird populations. Our results suggest that successful grassland bird conservation may depend upon linkages with ecosystem services on working agricultural lands and grassland-based marketing campaigns to engage the public. With further development, spatial models that link landowner decisions with biological outcomes can be essential tools for making conservation policy decisions. A coordinated non-traditional partnership will likely be necessary to clearly understand and systematically respond to the many conservation challenges facing grassland birds. PMID:26569108

  18. Strategic Grassland Bird Conservation throughout the Annual Cycle: Linking Policy Alternatives, Landowner Decisions, and Biological Population Outcomes.

    PubMed

    Drum, Ryan G; Ribic, Christine A; Koch, Katie; Lonsdorf, Eric; Grant, Evan; Ahlering, Marissa; Barnhill, Laurel; Dailey, Thomas; Lor, Socheata; Mueller, Connie; Pavlacky, David C; Rideout, Catherine; Sample, David

    2015-01-01

    Grassland bird habitat has declined substantially in the United States. Remaining grasslands are increasingly fragmented, mostly privately owned, and vary greatly in terms of habitat quality and protection status. A coordinated strategic response for grassland bird conservation is difficult, largely due to the scope and complexity of the problem, further compounded by biological, sociological, and economic uncertainties. We describe the results from a collaborative Structured Decision Making (SDM) workshop focused on linking social and economic drivers of landscape change to grassland bird population outcomes. We identified and evaluated alternative strategies for grassland bird conservation using a series of rapid prototype models. We modeled change in grassland and agriculture cover in hypothetical landscapes resulting from different landowner decisions in response to alternative socio-economic conservation policy decisions. Resulting changes in land cover at all three stages of the annual cycle (breeding, wintering, and migration) were used to estimate changes in grassland bird populations. Our results suggest that successful grassland bird conservation may depend upon linkages with ecosystem services on working agricultural lands and grassland-based marketing campaigns to engage the public. With further development, spatial models that link landowner decisions with biological outcomes can be essential tools for making conservation policy decisions. A coordinated non-traditional partnership will likely be necessary to clearly understand and systematically respond to the many conservation challenges facing grassland birds. PMID:26569108

  19. Quantifying drivers of population dynamics for a migratory bird throughout the annual cycle.

    PubMed

    Rushing, Clark S; Ryder, Thomas B; Marra, Peter P

    2016-01-27

    Worldwide, migratory species are undergoing rapid declines but understanding the factors driving these declines is hindered by missing information about migratory connectivity and the lack of data to quantify environmental processes across the annual cycle. Here, we combined range-wide information about migratory connectivity with global remote-sensing data to quantify the relative importance of breeding and non-breeding environmental processes to persistent long-term population declines of a migratory songbird, the wood thrush (Hylocichla mustelina). Consistent with theoretical predictions about population limitation of migratory birds, our results suggest that habitat loss and climate have contributed to the observed declines in wood thrush breeding abundance, yet the relative importance of breeding versus non-breeding factors is population-specific. For example, high-abundance core breeding populations appear to be more limited by habitat loss, whereas low-abundance, peripheral populations appear to be limited by climate-driven seasonal interactions. Further, our analysis indicates that the relative impact of breeding habitat loss is at least three to six times greater than the impact of equivalent non-breeding habitat loss and therefore the steepest regional declines have likely been driven by the loss of breeding habitat. These results underscore the need for population-specific conservation strategies implemented throughout the annual cycle to reverse long-term declines. PMID:26817774

  20. Cecal populations of lactobacilli and bifidobacteria and Escherichia coli populations after in vivo Escherichia coli challenge in birds fed diets with purified lignin or mannanoligosaccharides.

    PubMed

    Baurhoo, B; Letellier, A; Zhao, X; Ruiz-Feria, C A

    2007-12-01

    Two experiments were conducted to evaluate lignin and mannanoligosaccharides as alternatives to antibiotic growth promoters in broilers. Dietary treatments for the 2 studies were 1) negative control (CTL-, antibiotic free); 2) positive control (CTL+, diet 1 + 11 mg of virginiamycin/kg); 3) mannanoligosaccharide (MOS; diet 1 + BioMos: 0.2% to 21 d and 0.1% thereafter); 4) LL (diet 1 + 1.25% Alcell lignin); and 5) HL (diet 1 + 2.5% Alcell lignin). In experiment 1, each treatment was assigned to 4 pen replicates (52 birds each). Body weight and feed intake were recorded weekly for 38 d. At 28 and 38 d, cecal contents were assayed for lactobacilli and bifidobacteria. Body weight and feed intake did not differ among dietary treatments. At d 38, the lactobacilli population was greatest (P < 0.05) in birds fed MOS, whereas LL-fed birds had greater (P < 0.05) lactobacilli load than those fed CTL+. Bifidobacteria load was greater (P < 0.05) in birds fed MOS or LL compared with those fed CTL+ at both d 28 and 38. However, at d 28 and 38, lactobacilli and bifidobacteria loads were lowest (P < 0.05) in CTL+ or HL-fed birds. In experiment 2, 21-d-old birds from the initial flock were transferred to cages for oral Escherichia coli (O2 and O88 serotypes) challenge (12 birds/treatment). After 3, 6, and 9 d, cecal loads of E. coli were determined. Birds fed HL had a lower E. coli load (P < 0.05) than birds fed CTL- or CTL+ at d 3, and lower than birds fed CTL- at d 6. At d 9, the E. coli load was lower (P < 0.05) in birds fed MOS or HL than in those fed the CTL- or CTL+ diets; LL-fed birds had lower E. coli load than those fed CTL-. Birds fed MOS or LL had a comparative advantage over CTL+ birds in increasing populations of lactobacilli and bifidobacteria and lowering E. coli loads after challenge. PMID:18029796

  1. Recent trends of the population in the Soviet Union.

    PubMed

    Kono, S

    1990-10-01

    The author, who attended a UN seminar held in the USSR, reports on the recent trends of population dynamics in the host country, the 3rd most populous nation in the world. In 1989, the USSR's population was 286.72 million, up from 262.44 million in 1979. 51.4% of the population lives in the Russian Soviet Federated Socialist Republic, an intriguing fact considering that there are a total of 15 republics in the USSR. Moreover, 3 republics (Russia, the Ukraine, and Byelorussia) account for 73.2% of the country's total population. The author questions reports that the Ukraine is seeking independence, noting the similarity in ethnicity and language between the Ukrainians and Russians. However, the author acknowledges cultural differences between Russia and the Baltic republics (latvia, Lithuania, and Estonia). Differences also exist between republics concerning fertility rates. While Russia, Byelorussia, and the Baltic states have a total fertility of 2.1 (net replacement fertility), minority republics in the southern region have dramatically higher fertility rates: 5.5 for Tajik, 4.7 for Uzbek and Turkemia, and 4.1 in Kyrgyz. Another significant fact of the USSR's population dynamics is its stagnant, or even retarded, life expectancy. Between 1960-70, life expectancy was 64.4 for men and 73.4 for women. Between 1979-80, these figures dropped to 62.2 and 72.5, respectively. They somewhat recovered during 1985-86, increasing to 64.2 for men and 73.3 for women. Throughout the USSR, but especially in Russia, there is a wide disparity in the life expectancy between men and women (as high as 11.5 years in Russia from (1979-80). In his visit, the author found that Soviet demographers and statisticians spoke candidly and openly, reflecting the changes brought about by perestroika and glasnost. PMID:12316754

  2. Ranges of North American breeding birds: visualizing long-term population changes in North American breeding birds

    USGS Publications Warehouse

    Price, Jeff

    1995-01-01

    These maps show changes in the distribution and abundance patterns of some North American birds for the last 20 years. For each species there are four maps, each representing the average distribution and abundance pattern over the five-year periods 1970-1974, 1975-1979, 1980-1984, and 1985-1989. The maps are based on data collected by the USFWS/CWS Breeding Bird Survey (BBS). Only BBS routes that were run at least once during each of the five-year periods were used (about 1300 routes). The maps were created in the software package Surfer using a kriging technique to interpolate mean relative abundances for areas where no routes were run. On each map, a portion of northeast Canada was blanked out because there were not enough routes to allow for adequate interpolation. All of the maps in this presentation use the same color scale (shown below). The minimum value mapped was 0.5 birds per route, which represents the edge of the species range.

  3. High Genetic Diversity of Newcastle Disease Virus in Wild and Domestic Birds in Northeastern China from 2013 to 2015 Reveals Potential Epidemic Trends.

    PubMed

    Zhang, Pingze; Xie, Guangyao; Liu, Xinxin; Ai, Lili; Chen, Yanyu; Meng, Xin; Bi, Yuhai; Chen, Jianjun; Sun, Yuzhang; Stoeger, Tobias; Ding, Zhuang; Yin, Renfu

    2016-03-01

    Newcastle disease (ND), caused by the virulent Newcastle disease virus (NDV), is one of the most important viral diseases of birds globally, but little is currently known regarding enzootic trends of NDV in northeastern China, especially for class I viruses. Thus, we performed a surveillance study for NDV in northeastern China from 2013 to 2015. A total 755 samples from wild and domestic birds in wetlands and live bird markets (LBMs) were collected, and 10 isolates of NDV were identified. Genetic and phylogenetic analyses showed that five isolates from LBMs belong to class I subgenotype 1b, two (one from wild birds and one from LBMs) belong to the vaccine-like class II genotype II, and three (all from wild birds) belong to class II subgenotype Ib. Interestingly, the five class I isolates had epidemiological connections with viruses from southern, eastern, and southeastern China. Our findings, together with recent prevalence trends of class I and virulent class II NDV in China, suggest possible virus transmission between wild and domestic birds and the potential for an NDV epidemic in the future. PMID:26712543

  4. Hair mercury levels in Amazonian populations: spatial distribution and trends

    PubMed Central

    2009-01-01

    Background Mercury is present in the Amazonian aquatic environments from both natural and anthropogenic sources. As a consequence, many riverside populations are exposed to methylmercury, a highly toxic organic form of mercury, because of their intense fish consumption. Many studies have analysed this exposure from different approaches since the early nineties. This review aims to systematize the information in spatial distribution, comparing hair mercury levels by studied population and Amazonian river basin, looking for exposure trends. Methods The reviewed papers were selected from scientific databases and online libraries. We included studies with a direct measure of hair mercury concentrations in a sample size larger than 10 people, without considering the objectives, approach of the study or mercury speciation. The results are presented in tables and maps by river basin, displaying hair mercury levels and specifying the studied population and health impact, if any. Results The majority of the studies have been carried out in communities from the central Amazonian regions, particularly on the Tapajós River basin. The results seem quite variable; hair mercury means range from 1.1 to 34.2 μg/g. Most studies did not show any significant difference in hair mercury levels by gender or age. Overall, authors emphasized fish consumption frequency as the main risk factor of exposure. The most studied adverse health effect is by far the neurological performance, especially motricity. However, it is not possible to conclude on the relation between hair mercury levels and health impact in the Amazonian situation because of the relatively small number of studies. Conclusions Hair mercury levels in the Amazonian regions seem to be very heterogenic, depending on several factors. There is no obvious spatial trend and there are many areas that have never been studied. Taking into account the low mercury levels currently handled as acceptable, the majority of the Amazonian

  5. Epidemiology of the Emergent Disease Paridae pox in an Intensively Studied Wild Bird Population

    PubMed Central

    Lachish, Shelly; Lawson, Becki; Cunningham, Andrew A.; Sheldon, Ben C.

    2012-01-01

    Paridae pox, a novel avipoxvirus infection, has recently been identified as an emerging infectious disease affecting wild tit species in Great Britain. The incursion of Paridae pox to a long-term study site where populations of wild tits have been monitored in detail for several decades provided a unique opportunity to obtain information on the local-scale epidemiological characteristics of this novel infection during a disease outbreak. Using captures of >8000 individual birds, we show that, within two years of initial emergence, Paridae pox had become established within the population of great tits (Parus major) reaching relatively high peak prevalence (10%), but was far less prevalent (<1%) in sympatric populations of several other closely related, abundant Paridae species. Nonlinear smoothing models revealed that the temporal pattern of prevalence among great tits was characterised by within-year fluctuations indicative of seasonal forcing of infection rates, which was likely driven by multiple environmental and demographic factors. There was individual heterogeneity in the course of infection and, although recovery was possible, diseased individuals were far less likely to be recaptured than healthy individuals, suggesting a survival cost of infection. This study demonstrates the value of long-term monitoring for obtaining key epidemiological data necessary to understand disease dynamics, spread and persistence in natural populations. PMID:23185230

  6. Second generation anticoagulant rodenticides in predatory birds: Probabilistic characterisation of toxic liver concentrations and implications for predatory bird populations in Canada.

    PubMed

    Thomas, Philippe J; Mineau, Pierre; Shore, Richard F; Champoux, Louise; Martin, Pamela A; Wilson, Laurie K; Fitzgerald, Guy; Elliott, John E

    2011-07-01

    Second-generation anticoagulant rodenticides (SGARs) are widely used to control rodent pests but exposure and poisonings occur in non-target species, such as birds of prey. Liver residues are often analysed to detect exposure in birds found dead but their use to assess toxicity of SGARs is problematic. We analysed published data on hepatic rodenticide residues and associated symptoms of anticoagulant poisoning from 270 birds of prey using logistic regression to estimate the probability of toxicosis associated with different liver SGAR residues. We also evaluated exposure to SGARs on a national level in Canada by analysing 196 livers from great horned owls (Bubo virginianus) and red-tailed hawks (Buteo jamaicensis) found dead at locations across the country. Analysis of a broader sample of raptor species from Quebec also helped define the taxonomic breadth of contamination. Calculated probability curves suggest significant species differences in sensitivity to SGARs and significant likelihood of toxicosis below previously suggested concentrations of concern (<0.1mg/kg). Analysis of birds from Quebec showed that a broad range of raptor species are exposed to SGARs, indicating that generalised terrestrial food chains could be contaminated in the vicinity of the sampled areas. Of the two species for which we had samples from across Canada, great horned owls are exposed to SGARs to a greater extent than red-tailed hawks and the liver residue levels were also higher. Using our probability estimates of effect, we estimate that a minimum of 11% of the sampled great horned owl population is at risk of being directly killed by SGARs. This is the first time the potential mortality impact of SGARs on a raptor population has been estimated. PMID:21481471

  7. Effects of five-year DDT application on breeding bird population

    USGS Publications Warehouse

    Robbins, C.S.; Springer, P.F.; Webster, C.G.

    1951-01-01

    Aerial applications of DDT in oil at the rate of 2 pounds per acre applied over a four-year interval on bottomland forest resulted in a 26 percent decrease in the breeding bird population by the fifth spring. The American redstart, parula warbler, and red-eyed vireo suffered decreases of 44 percent, 40. percent, and 28 percent, respectively, over the four-year period. Only the redstart decreased significantly immediately following application of the spray; a few days after the first, second, and fifth annual sprayings an average of 23 percent of redstart territories were deserted. No significant decrease was observed for other species, either immediately following spraying, or over the four-year period.

  8. Trends in the exploitation of South Atlantic shark populations.

    PubMed

    Barreto, Rodrigo; Ferretti, Francesco; Flemming, Joanna M; Amorim, Alberto; Andrade, Humber; Worm, Boris; Lessa, Rosangela

    2016-08-01

    Approximately 25% of globally reported shark catches occur in Atlantic pelagic longline fisheries. Strong declines in shark populations have been detected in the North Atlantic, whereas in the South Atlantic the situation is less clear, although fishing effort has been increasing in this region since the late 1970s. We synthesized information on shark catch rates (based on 871,177 sharks caught on 86,492 longline sets) for the major species caught by multiple fleets in the South Atlantic between 1979 and 2011. We complied records from fishing logbooks of fishing companies, fishers, and onboard observers that were supplied to Brazilian institutions. By using exploratory data analysis and literature sources, we identified 3 phases of exploitation in these data (Supporting Information). From 1979 to 1997 (phase A), 5 fleets (40 vessels) fished mainly for tunas. From 1998 to 2008 (phase B), 20 fleets (100 vessels) fished for tunas, swordfishes, and sharks. From 2008 to 2011 (phase C), 3 fleets (30 vessels) fished for multiple species, but restrictive measures were implemented. We used generalized linear models to standardize catch rates and identify trends in each of these phases. Shark catch rates increased from 1979 to 1997, when fishing effort was low, decreased from 1998 to 2008, when fishing effort increased substantially, and remained stable or increased from 2008 to 2011, when fishing effort was again low. Our results indicate that most shark populations affected by longlines in the South Atlantic are currently depleted, but these populations may recover if fishing effort is reduced accordingly. In this context, it is problematic that comprehensive data collection, monitoring, and management of these fisheries ceased after 2012. Concurrently with the fact that Brazil is newly identified by FAO among the largest (and in fastest expansion) shark sub-products consumer market worldwide. PMID:26634410

  9. Persistent impacts of West Nile virus on North American bird populations

    PubMed Central

    George, T. Luke; Harrigan, Ryan J.; LaManna, Joseph A.; DeSante, David F.; Saracco, James F.; Smith, Thomas B.

    2015-01-01

    Since its introduction to North America in 1999, West Nile virus (WNV) has had devastating impacts on native host populations, but to date these impacts have been difficult to measure. Using a continental-scale dataset comprised of a quarter-million birds captured over nearly two decades and a recently developed model of WNV risk, we estimated the impact of this emergent disease on the survival of avian populations. We find that populations were negatively affected by WNV in 23 of the 49 species studied (47%). We distinguished two groups of species: those for which WNV negatively impacted survival only during initial spread of the disease (n = 11), and those that show no signs of recovery since disease introduction (n = 12). Results provide a novel example of the taxonomic breadth and persistent impacts of this wildlife disease on a continental scale. Phylogenetic analyses further identify groups (New World sparrows, finches, and vireos) disproportionally affected by temporary or persistent WNV effects, suggesting an evolutionary dimension of disease risk. Identifying the factors affecting the persistence of a disease across host species is critical to mitigating its effects, particularly in a world marked by rapid anthropogenic change. PMID:26578774

  10. Predicting foraging wading bird populations in Everglades National Park from seasonal hydrologic statistics under different management scenarios

    NASA Astrophysics Data System (ADS)

    Kwon, Hyun-Han; Lall, Upmanu; Engel, Vic

    2011-09-01

    The ability to map relationships between ecological outcomes and hydrologic conditions in the Everglades National Park (ENP) is a key building block for their restoration program, a primary goal of which is to improve conditions for wading birds. This paper presents a model linking wading bird foraging numbers to hydrologic conditions in the ENP. Seasonal hydrologic statistics derived from a single water level recorder are well correlated with water depths throughout most areas of the ENP, and are effective as predictors of wading bird numbers when using a nonlinear hierarchical Bayesian model to estimate the conditional distribution of bird populations. Model parameters are estimated using a Markov chain Monte Carlo (MCMC) procedure. Parameter and model uncertainty is assessed as a byproduct of the estimation process. Water depths at the beginning of the nesting season, the average dry season water level, and the numbers of reversals from the dry season recession are identified as significant predictors, consistent with the hydrologic conditions considered important in the production and concentration of prey organisms in this system. Long-term hydrologic records at the index location allow for a retrospective analysis (1952-2006) of foraging bird numbers showing low frequency oscillations in response to decadal fluctuations in hydroclimatic conditions. Simulations of water levels at the index location used in the Bayesian model under alternative water management scenarios allow the posterior probability distributions of the number of foraging birds to be compared, thus providing a mechanism for linking management schemes to seasonal rainfall forecasts.

  11. Distribution and abundance of marine bird and pinniped populations within Port Foster, Deception Island, Antarctica

    NASA Astrophysics Data System (ADS)

    Kendall, Katrina A.; Ruhl, Henry A.; Wilson, Robert C.

    2003-06-01

    Seabirds and pinnipeds were surveyed during four cruises from March 1999 to November 2000 at Port Foster, Deception Island, Antarctica. Abundances and distributions of three species of pinnipeds, Arctocephalus gazella (Antarctic fur seals), Leptonychotes weddelli (Weddell seals), and Lobodon carcinophagus (crabeater seals), and 11 species of marine birds were documented within Port Foster. A. gazella was the dominant pinniped within Port Foster; its abundance has increased since the 1986/87 austral summer season. A. gazella were concentrated at the entrance to Port Foster. More pinnipeds were observed during the austral summer than during the spring. The most dominant seabird, Pygoscelis antarctica (chinstrap penguin), was concentrated along the rocky cliffs behind the beaches where A. gazella hauled out. Larus dominicanus (kelp gull) and Daption capense (cape petrel) were the most dominant flying seabirds. All other seabird species were more widely distributed around Port Foster than P. antarctica. There was no clear trend in abundances of seabirds over the study period. It is possible that the protected area of Port Foster provides refuge for vagrants of colonies along the outer periphery of the island and as a stopover point for migrating species.

  12. Polybrominated diphenyl ether trends in eggs of marine and freshwater birds from British Columbia, Canada, 1979-2002.

    PubMed

    Elliott, John E; Wilson, Laurie K; Wakeford, Bryan

    2005-08-01

    Temporal, spatial, and interspecific trends in polybrominated diphenyl ether (PBDE) flame retardants were determined in eggs of marine and freshwater bird species from the province of British Columbia, Canada. Temporal trends in the Fraser River estuary, 1983-2002, were examined by analysis of eggs of great blue herons (Ardea herodias) and from the Strait of Georgia marine ecosystem, 1979-2002, in eggs of double-crested cormorants (Phalacrocorax auritus). Results were compared to those from eggs of the osprey (Pandion haliaetus) taken along the lower Fraser River and along the Columbia River near Castlegar, British Columbia, and of a pelagic seabird, the Leach's storm-petrel (Oceanodroma leucorhoa), collected at a colony on the Queen Charlotte Islands. Mean concentration of sigmaPBDE, 455 microg/kg w.w., were highest in heron eggs collected in 2002 from the Fraser estuary. Concentrations in eggs of cormorants and ospreys taken from sites of varying urban influence tended to be about half that value. Leach's storm petrel eggs had only trace amounts of sigmaPBDE (3.38 microg/kg), despite having similar concentrations of PCBs and organochlorine pesticides to the other species. PBDEs increased exponentially with a doubling time of 5.7 years in eggs of both herons and cormorants. Over this period of increasing PBDEs, major chlorinated hydrocarbons, such as PCBs and DDE, were stable or decreased. The PBDE pattern was relatively consistent in most years and sites, with BDEs 47 > 100 > 99 > 153 > 154 > 28 > 183. This was interpreted as evidence of technical pentaBDE formulations as primary sources of the contamination, with the octaBDE formulations as secondary. Higher resolution analysis of a subsample of the eggs revealed the presence of up to nine other congeners, including BDE209 (range: 0.9-1.8 microg/kg), indicating exposure and uptake of decaBDE sourced congeners in North American foodchains. At some locations, concentrations of pentabrominated congeners and

  13. Bird community composition

    USGS Publications Warehouse

    Antrobus, T.J.; Guilfoyle, M.P.; Barrow, W.C., Jr.; Hamel, P.B.; Wakeley, J.S.

    2000-01-01

    Neotropical migrants are birds that breed in North America and winter primarily in Central and South America. Long-term population studies of birds in the Eastern United States indicated declines of some forest-dwelling birds, many of which winter in the Neotropics (Peterjohn and others 1995). These declines were attributed to loss of wintering and breeding habitat due to deforestation and fragmentation, respectively. Many species of Nearctic migrants--birds that breed in the northern regions of North America and winter in the Southern United States--are also experiencing population declines. Because large areas of undistrubed, older, bottomland hardwood forests oftern contain large numbers of habitat specialists, including forest-interior neotropical migrants and wintering Nearctic migrants, these forests may be critical in maintaining avian diversity. This study had two primary objectivs: (1) to create a baseline data set that can be used as a standard against which other bottomland hardwood forests can be compared, and (2) to establish long-term monitoring stations during both breeding and wintering seasons to discern population trends of avian species using bottomland hardwood forests.

  14. Changes in patch features may exacerbate or compensate for the effect of habitat loss on forest bird populations.

    PubMed

    Magrach, Ainhoa; Larrinaga, Asier R; Santamaría, Luis

    2011-01-01

    One and a half centuries after Darwin visited Chiloe Island, what he described as "…an island covered by one great forest…" has lost two-thirds of its forested areas. At this biodiversity hotspot, forest surface is becoming increasingly fragmented due to unregulated logging, clearing for pastures and replacement by exotic tree plantations. Decrease in patch size, increased isolation and "edge effects" can influence the persistence of forest species in remnant fragments. We assessed how these variables affect local density for six forest birds, chosen to include the most important seed dispersers (four species) and bird pollinators (two species, one of which acts also as seed disperser), plus the most common insectivore (Aphrastura spinicauda). Based on cue-count point surveys (8 points per fragment), we estimated bird densities for each species in 22 forest fragments of varying size, shape, isolation and internal-habitat structure (e.g. tree size and epiphyte cover). Bird densities varied with fragment connectivity (three species) and shape (three species), but none of the species was significantly affected by patch size. Satellite image analyses revealed that, from 1985 to 2008, forested area decreased by 8.8% and the remaining forest fragments became 16% smaller, 58-73% more isolated and 11-50% more regular. During that period, bird density estimates for the northern part of Chiloé (covering an area of 1214.75 km(2)) decreased for one species (elaenia), increased for another two (chucao and hummingbird) and did not vary for three (rayadito, thrust and blackbird). For the first three species, changes in patch features respectively exacerbated, balanced and overcame the effects of forest loss on bird population size (landscape-level abundance). Hence, changes in patch features can modulate the effect of habitat fragmentation on forest birds, suggesting that spatial planning (guided by spatially-explicit models) can be an effective tool to facilitate their

  15. Avian malaria in Hawaiian forest birds: Infection and population impacts across species and elevations

    USGS Publications Warehouse

    Samuel, Michael D.; Woodworth, Bethany L.; Atkinson, Carter T.; Hart, P. J.; LaPointe, Dennis

    2015-01-01

    Wildlife diseases can present significant threats to ecological systems and biological diversity, as well as domestic animal and human health. However, determining the dynamics of wildlife diseases and understanding the impact on host populations is a significant challenge. In Hawai‘i, there is ample circumstantial evidence that introduced avian malaria (Plasmodium relictum) has played an important role in the decline and extinction of many native forest birds. However, few studies have attempted to estimate disease transmission and mortality, survival, and individual species impacts in this distinctive ecosystem. We combined multi-state capture-recapture (longitudinal) models with cumulative age-prevalence (cross-sectional) models to evaluate these patterns in Apapane, Hawai‘i Amakihi, and Iiwi in low-, mid-, and high-elevation forests on the island of Hawai‘i based on four longitudinal studies of 3–7 years in length. We found species-specific patterns of malaria prevalence, transmission, and mortality rates that varied among elevations, likely in response to ecological factors that drive mosquito abundance. Malaria infection was highest at low elevations, moderate at mid elevations, and limited in high-elevation forests. Infection rates were highest for Iiwi and Apapane, likely contributing to the absence of these species in low-elevation forests. Adult malaria fatality rates were highest for Iiwi, intermediate for Amakihi at mid and high elevations, and lower for Apapane; low-elevation Amakihi had the lowest malaria fatality, providing strong evidence of malaria tolerance in this low-elevation population. Our study indicates that hatch-year birds may have greater malaria infection and/or fatality rates than adults. Our study also found that mosquitoes prefer feeding on Amakihi rather than Apapane, but Apapane are likely a more important reservoir for malaria transmission to mosquitoes. Our approach, based on host abundance and infection rates, may be an

  16. Smoking cessation and mortality trends among two United States populations.

    PubMed

    Enstrom, J E

    1999-09-01

    The long-term impact of smoking cessation on mortality is assessed among two U.S. populations: a large cohort of U.S. veterans aged 55-64 at entry and followed from 1954 through 1979 and the NHANES I Epidemiologic Followup Study (NHEFS) cohort of a national sample of U.S. adults aged 55-74 at entry and followed from 1971 through 1992. Direct and indirect survey data indicate that 50-70% of those who were current cigarette smokers at entry had quit smoking during the 19- to 26-year follow-up periods. The impact of smoking cessation on mortality among the cigarette smokers as a whole has been assessed by determining the time trend of the relative risk (RR) of death and 95% confidence interval (CI) for the cigarette smokers compared with never-smokers over the entire follow-up period in both cohorts. The total death rates for the 1954/57 U.S. veteran smokers as a whole (63,159 males) have converged only slightly toward those of never-smokers, from RR = 1.65 (1.58-1.72) during 1954-1959 to RR = 1.61 (1.58-1.63) during 1954-1979. The lung cancer death rates for 1954/57 smokers as a whole have not converged toward those of never-smokers, with RR = 10.89 (7.70-15.41) during 1954-1959 and RR = 11.10 (9.78-12.61) during 1954-1979. The total death rates for the 1971-1975 NHEFS smokers as a whole (694 males and 1116 females) have not converged toward those of never-smokers. For males, RR = 1.92 (1.46-2.52) during 1971-1982 and RR = 1.96 (1.63-2.36) during 1971-1992; for females, RR = 1.79 (1.31-2.46) during 1971-1982 and RR = 1.79 (1.47-2.17) during 1971-1992. The lung cancer death rates have diverged, based on small numbers of deaths. For males, RR = 15.76 (2.06-120.61) during 1971-1982 and RR = 22.20 (5.31-92.92) during 1971-1992; for females, RR = 2.92 (0.57-15.06) during 1971-1982 and RR = 4.74 (1.94-11.59) during 1971-1992. These trends are contrary to the substantial convergence predicted by the death rate trends among U.S. veterans who were former smokers at the

  17. Spatial and temporal trends of contaminants in eggs of wading birds from San Francisco Bay, California

    USGS Publications Warehouse

    Hothem, R.L.; Roster, D.L.; King, K.A.; Keldsen, T.J.; Marois, K.C.; Wainwright, S.E.

    1995-01-01

    Between 1989 and 1991, reproduction by black-crowned night-herons (Nycticorax nycticorax) and snowy egrets (Egretta thula) was studied at sites in San Francisco Bay. Eggs were collected from these and other bay sites and from South Wilbur Flood Area, a reference site in California's San Joaquin Valley. Eggs were analyzed for inorganic trace elements, organochlorine pesticides, and polychlorinated biphenyls (PCBs). Results were compared among sites and years and with results of previous studies. There was some evidence of impaired reproduction, but concentrations of contaminants were generally lower than threshold levels for such effects. Egg hatchability was generally good, with predation being the factor that most limited reproductive success. Mean PCB concentrations were generally higher in eggs from the south end of San Francisco Bay than from the north, but the only temporal change, an increase, was observed at Alcatraz Island. There were spatial differences for p,p'-DDE in night-heron eggs in 1990, but the highest mean concentration of DDE was in night-heron eggs from South Wilbur in 1991. Temporal declines in maximum concentrations of DDE in eggs were observed in the bay, but means did not change significantly over time, At Bair Island in the southern end of the bay, mean concentrations of mercury decreased while selenium increased in night-heron eggs over time, but there were no clear bay-wide spatial or temporal trends for either element.

  18. Spatial and temporal trends of contaminants in eggs of wading birds from San Francisco Bay, California

    SciTech Connect

    Hothem, R.L.; Marois, K.C.; Wainwright, S.E.; Roster, D.L.; King, K.A.; Keldsen, T.J.

    1995-08-01

    Between 1989 and 1991, reproduction by black-crowned night-herons (Nycticorax nycticorax) and snowy egrets (Egretta thula) was studied at sites in San Francisco Bay. Eggs were collected from these and other bay sites and from South Wilbur Flood Area, a reference site in California`s San Joaquin Valley. Eggs were analyzed for inorganic trace elements, organochlorine pesticides, and polychlorinated biphenyls (PCBs). Results were compared among sites and years and with results of previous studies. There was some evidence of impaired reproduction, but concentrations of contaminants were generally lower than threshold levels for such effects. Egg hatchability was generally good, with predation being the factor that most limited reproductive success. Mean PCB concentrations were generally higher in eggs from the south end of San Francisco Bay than from the north, but the only temporal change, an increase, was observed at Alcatraz Island. There were spatial differences for p,p{prime}-DDE in night-heron eggs in 1990, but the highest mean concentration of DDE was in night-heron eggs from South Wilbur in 1991. Temporal declines in maximum concentrations of DDE in eggs were observed in the bay, but means did not change significantly over time. At Bair Island in the southern end of the bay, mean concentrations of mercury decreased while selenium increased in night-heron eggs over time, but there were no clear bay-wide spatial or temporal trends for either element.

  19. Geographic variation in onset of singing among populations of two migratory birds

    NASA Astrophysics Data System (ADS)

    Gordo, Oscar; Sanz, Juan José; Lobo, Jorge M.

    2008-07-01

    Even though singing plays a major role in bird communication, environmental variables affecting the geographic patterns observed in the variation of singing onset within large areas have not previously been studied. The singing phenology of two long-distance migrants, the Cuckoo Cuculus canorus and the Nightingale Luscinia megarhynchos, recorded in thousands of sites throughout Spain, was related to a set of 51 explanatory variables by partial least squares regression. Observed variability in singing onset among localities follows spatial trends on an Iberian scale at 10 × 10 km resolution, and was well modelled by some environmental variables. Of these variables, climate was the most influential. Males of both species sang earlier in warmer and drier sites. Males who were near the Straits of Gibraltar and in the southern Iberian basins, which are geographic gradients closely related with climate in the Iberian Peninsula, were also heard earlier. Most environmental variables affected the singing activity of both species equally, i.e., the same environmental gradients are linked to singing onset. However, the models' predictions indicated differences in the geographical pattern in singing onset between both species, mainly related to their rates of progression during spring migration through Spain. Local variables, such as land uses, vegetation productivity or species abundance, played a minor role on singing onset spatial patterns. Therefore, models' composition supports the hypothesis that singing onset is a good proxy of arrival dates in migratory species, since those variables related to indirect effects on singing onset phenology through migratory progression and arrival to the breeding grounds showed the highest influence.

  20. State of Washington Population Trends, 1977. Washington State Information Report.

    ERIC Educational Resources Information Center

    Washington State Office of Program Planning and Fiscal Management, Olympia.

    As of April 1, 1977, Washington's population was estimated at 3,661,975--an increase of 248,725 since 1970. Prepared yearly, this report presents data on the official April 1 population estimates for cities, towns, and counties; components of population change; planned population forecasting activities; procedures which help make the housing unit…

  1. Chicago Children and Youth 1990-2010: Changing Population Trends and their Implications for Services

    ERIC Educational Resources Information Center

    Goerge, Robert; Dilts, John; Yang, Duck-Hye; Wasserman, Miriam; Clary, Anne

    2007-01-01

    This report draws on demographic data to examine and project trends in the size and composition of the child population in all seventy-seven Chicago communities up to the year 2010. The report highlights the changing age mix of Chicago children and provides some context in which to consider these demographic trends. It describes population changes…

  2. Mississippi's Farming & Nonfarming Population: A Comparison of Characteristics and Trends, 1950 to 1970.

    ERIC Educational Resources Information Center

    Bryant, Ellen S.

    Trends and changes in Mississippi farms, farmers, and farm populations were investigated for the period between 1950 and 1970 and comparisons were made between the farm population and that of the urban and rural nonfarm segments in terms of growth trends and 1970 characteristics. Data were drawn from both the Censuses of Agriculture (taken at five…

  3. Integrating paleoecology and genetics of bird populations in two sky island archipelagos

    PubMed Central

    McCormack, John E; Bowen, Bonnie S; Smith, Thomas B

    2008-01-01

    Background Genetic tests of paleoecological hypotheses have been rare, partly because recent genetic divergence is difficult to detect and time. According to fossil plant data, continuous woodland in the southwestern USA and northern Mexico became fragmented during the last 10,000 years, as warming caused cool-adapted species to retreat to high elevations. Most genetic studies of resulting 'sky islands' have either failed to detect recent divergence or have found discordant evidence for ancient divergence. We test this paleoecological hypothesis for the region with intraspecific mitochondrial DNA and microsatellite data from sky-island populations of a sedentary bird, the Mexican jay (Aphelocoma ultramarina). We predicted that populations on different sky islands would share common, ancestral alleles that existed during the last glaciation, but that populations on each sky island, owing to their isolation, would contain unique variants of postglacial origin. We also predicted that divergence times estimated from corrected genetic distance and a coalescence model would post-date the last glacial maximum. Results Our results provide multiple independent lines of support for postglacial divergence, with the predicted pattern of shared and unique mitochondrial DNA haplotypes appearing in two independent sky-island archipelagos, and most estimates of divergence time based on corrected genetic distance post-dating the last glacial maximum. Likewise, an isolation model based on multilocus gene coalescence indicated postglacial divergence of five pairs of sky islands. In contrast to their similar recent histories, the two archipelagos had dissimilar historical patterns in that sky islands in Arizona showed evidence for older divergence, suggesting different responses to the last glaciation. Conclusion This study is one of the first to provide explicit support from genetic data for a postglacial divergence scenario predicted by one of the best paleoecological records in the

  4. USE OF CITIZEN BIRD POPULATION MONITORING DATA FOR ECOLOGICAL RISK ASSESSMENT

    EPA Science Inventory

    Birds are among the most conspicuous and easily monitored indicators of environmental health and change. Although volunteer avian monitoring ('citizen science') programs provide unique opportunities to gather data at fine and broad geographic scales simultaneously, and over long...

  5. Genetically diverse coronaviruses in captive bird populations in a Brazilian zoological park.

    PubMed

    Cardoso, Tereza C; Teixeira, Maria Cecília B; Gomes, Deriane E; Jerez, Antônio José

    2011-02-01

    This study aimed to investigate the occurrence of coronaviruses (CoVs) in captive birds placed inside a zoological park in Brazil. The role of captive birds in the epidemiology of CoVs in the tropics is poorly understood. A total of 25 (n=25) different species were tested for viral RNA using individual fecal samples collected from healthy birds. Reverse transcription-polymerase chain reaction targeting the 3' untranslated region was used to detect CoV RNA, and positive samples were submitted for sequence analysis. The phylogenetic search revealed nine mutations in the black shouldered peafowl (Pavus cristatus) CoV sequence, which clustered separately from samples previously described in England. This is the first report on the detection of the CoV genome in captive birds in Brazil. PMID:21142971

  6. Quantitative assessment of the importance of phenotypic plasticity in adaptation to climate change in wild bird populations.

    PubMed

    Vedder, Oscar; Bouwhuis, Sandra; Sheldon, Ben C

    2013-07-01

    Predictions about the fate of species or populations under climate change scenarios typically neglect adaptive evolution and phenotypic plasticity, the two major mechanisms by which organisms can adapt to changing local conditions. As a consequence, we have little understanding of the scope for organisms to track changing environments by in situ adaptation. Here, we use a detailed individual-specific long-term population study of great tits (Parus major) breeding in Wytham Woods, Oxford, UK to parameterise a mechanistic model and thus directly estimate the rate of environmental change to which in situ adaptation is possible. Using the effect of changes in early spring temperature on temporal synchrony between birds and a critical food resource, we focus in particular on the contribution of phenotypic plasticity to population persistence. Despite using conservative estimates for evolutionary and reproductive potential, our results suggest little risk of population extinction under projected local temperature change; however, this conclusion relies heavily on the extent to which phenotypic plasticity tracks the changing environment. Extrapolating the model to a broad range of life histories in birds suggests that the importance of phenotypic plasticity for adjustment to projected rates of temperature change increases with slower life histories, owing to lower evolutionary potential. Understanding the determinants and constraints on phenotypic plasticity in natural populations is thus crucial for characterising the risks that rapidly changing environments pose for the persistence of such populations. PMID:23874152

  7. A Method for Investigating Population Declines of Migratory Birds Using Stable Isotopes: Origins of Harvested Lesser Scaup in North America

    PubMed Central

    Hobson, Keith A.; Wunder, Michael B.; Van Wilgenburg, Steven L.; Clark, Robert G.; Wassenaar, Leonard I.

    2009-01-01

    Background Elucidating geographic locations from where migratory birds are recruited into adult breeding populations is a fundamental but largely elusive goal in conservation biology. This is especially true for species that breed in remote northern areas where field-based demographic assessments are logistically challenging. Methodology/Findings Here we used hydrogen isotopes (δD) to determine natal origins of migrating hatch-year lesser scaup (Aythya affinis) harvested by hunters in the United States from all North American flyways during the hunting seasons of 1999–2000 (n = 412) and 2000–2001 (n = 455). We combined geospatial, observational, and analytical data sources, including known scaup breeding range, δD values of feathers from juveniles at natal sites, models of δD for growing-season precipitation, and scaup band-recovery data to generate probabilistic natal origin landscapes for individual scaup. We then used Monte Carlo integration to model assignment uncertainty from among individual δD variance estimates from birds of known molt origin and also from band-return data summarized at the flyway level. We compared the distribution of scaup natal origin with the distribution of breeding population counts obtained from systematic long-term surveys. Conclusions/Significance Our analysis revealed that the proportion of young scaup produced in the northern (above 60°N) versus the southern boreal and Prairie-Parkland region was inversely related to the proportions of breeding adults using these regions, suggesting that despite having a higher relative abundance of breeding adults, the northern boreal region was less productive for scaup recruitment into the harvest than more southern biomes. Our approach for evaluating population declines of migratory birds (particularly game birds) synthesizes all available distributional data and exploits the advantages of intrinsic isotopic markers that link individuals to geography. PMID:19946360

  8. Aging in France: Population Trends, Policy Issues, and Research Institutions

    ERIC Educational Resources Information Center

    Beland, Daniel; Durandal, Jean-Philippe Viriot

    2013-01-01

    Like in other advanced industrial countries, in France, demographic aging has become a widely debated research and policy topic. This article offers a brief overview of major aging-related trends in France. The article describes France's demographics of aging, explores key policy matters, maps the institutional field of French social gerontology…

  9. Effects of land use on bird populations and pest control services on coffee farms.

    PubMed

    Railsback, Steven F; Johnson, Matthew D

    2014-04-22

    Global increases in both agriculture and biodiversity awareness raise a key question: Should cropland and biodiversity habitat be separated, or integrated in mixed land uses? Ecosystem services by wildlife make this question more complex. For example, birds benefit agriculture by preying on pest insects, but other habitat is needed to maintain the birds. Resulting land use questions include what areas and arrangements of habitat support sufficient birds to control pests, whether this pest control offsets the reduced cropland, and the comparative benefits of "land sharing" (i.e., mixed cropland and habitat) vs. "land sparing" (i.e., separate areas of intensive agriculture and habitat). Such questions are difficult to answer using field studies alone, so we use a simulation model of Jamaican coffee farms, where songbirds suppress the coffee berry borer (CBB). Simulated birds select habitat and prey in five habitat types: intact forest, trees (including forest fragments), shade coffee, sun coffee, and unsuitable habitat. The trees habitat type appears to be especially important, providing efficient foraging and roosting sites near coffee plots. Small areas of trees (but not forest alone) could support a sufficient number of birds to suppress CBB in sun coffee; the degree to which trees are dispersed within coffee had little effect. In simulations without trees, shade coffee supported sufficient birds to offset its lower yield. High areas of both trees and shade coffee reduced pest control because CBB was less often profitable prey. Because of the pest control service provided by birds, land sharing was predicted to be more beneficial than land sparing in this system. PMID:24711377

  10. Effects of land use on bird populations and pest control services on coffee farms

    PubMed Central

    Railsback, Steven F.; Johnson, Matthew D.

    2014-01-01

    Global increases in both agriculture and biodiversity awareness raise a key question: Should cropland and biodiversity habitat be separated, or integrated in mixed land uses? Ecosystem services by wildlife make this question more complex. For example, birds benefit agriculture by preying on pest insects, but other habitat is needed to maintain the birds. Resulting land use questions include what areas and arrangements of habitat support sufficient birds to control pests, whether this pest control offsets the reduced cropland, and the comparative benefits of “land sharing” (i.e., mixed cropland and habitat) vs. “land sparing” (i.e., separate areas of intensive agriculture and habitat). Such questions are difficult to answer using field studies alone, so we use a simulation model of Jamaican coffee farms, where songbirds suppress the coffee berry borer (CBB). Simulated birds select habitat and prey in five habitat types: intact forest, trees (including forest fragments), shade coffee, sun coffee, and unsuitable habitat. The trees habitat type appears to be especially important, providing efficient foraging and roosting sites near coffee plots. Small areas of trees (but not forest alone) could support a sufficient number of birds to suppress CBB in sun coffee; the degree to which trees are dispersed within coffee had little effect. In simulations without trees, shade coffee supported sufficient birds to offset its lower yield. High areas of both trees and shade coffee reduced pest control because CBB was less often profitable prey. Because of the pest control service provided by birds, land sharing was predicted to be more beneficial than land sparing in this system. PMID:24711377

  11. Evidence for r- and K-selection in a wild bird population: a reciprocal link between ecology and evolution.

    PubMed

    Sæther, Bernt-Erik; Visser, Marcel E; Grøtan, Vidar; Engen, Steinar

    2016-04-27

    Understanding the variation in selection pressure on key life-history traits is crucial in our rapidly changing world. Density is rarely considered as a selective agent. To study its importance, we partition phenotypic selection in fluctuating environments into components representing the population growth rate at low densities and the strength of density dependence, using a new stochastic modelling framework. We analysed the number of eggs laid per season in a small song-bird, the great tit, and found balancing selection favouring large clutch sizes at small population densities and smaller clutches in years with large populations. A significant interaction between clutch size and population size in the regression for the Malthusian fitness reveals that those females producing large clutch sizes at small population sizes also are those that show the strongest reduction in fitness when population size is increased. This provides empirical support for ongoing r- and K-selection in this population, favouring phenotypes with large growth rates r at small population sizes and phenotypes with high competitive skills when populations are close to the carrying capacity K This selection causes long-term fluctuations around a stable mean clutch size caused by variation in population size, implying that r- and K-selection is an important mechanism influencing phenotypic evolution in fluctuating environments. This provides a general link between ecological dynamics and evolutionary processes, operating through a joint influence of density dependence and environmental stochasticity on fluctuations in population size. PMID:27122550

  12. Preliminary RSCCD Population Trends from the 1990 Census. Research, Planning, Resource Development Report.

    ERIC Educational Resources Information Center

    Slark, Julie; Nguyen, Huong

    Drawing from 1990 U.S. Censes data, a study was conducted of population trends in the Rancho Santiago Community College (California) District (RSCCD). Study findings included the following: (1) the population of the RSCCD increased by 32% from 1980 to 1990, larger than the statewide increase of 26%; (2) the 1990 RSCCD population was 482,224 and is…

  13. Population, consumption trends call for new environmental policies.

    PubMed

    1998-04-01

    This article highlights the need for new environmental policies. 38 industrialized countries gave commitments to protect the environment by reducing greenhouse gas emissions. But, a report on "Population Change, Resources, and the Environment" indicated that high levels of resource consumption in developed countries are a problem also, as are the complex environmental consequences of rapid population growth in developing countries. Global population is expected to include at least another 2 billion people by the mid-21st century. This growth will occur mostly in countries that lack the resources to invest in sound environmental policies and that may not adopt economic growth with little environmental impact. Additional population requires additional food, water, and shelter. The links between the environment and population include social structures, political systems, and lifestyles. Population is increasing the fastest in countries with the least efficient food production and distribution systems. Access to safe drinking water is constrained by poverty, poor infrastructure, and pollution of waterways and groundwater. A major share of economic growth will occur in cities. Population shifts to cities will create demand for health care and education, and encroach on surrounding farmland. Global marine fish stocks are being depleted. Logging and agriculture threaten forest resources. The report stresses that government policies that minimize the environmental impact of humans should promote recycling, eliminate subsidies that distort environmental costs of scarce resources, and implement better forest and fishery management. Politicians must think globally and act locally. PMID:12293547

  14. Population Trend of the World’s Monitored Seabirds, 1950-2010

    PubMed Central

    Karpouzi, Vasiliki; Pauly, Daniel

    2015-01-01

    Seabird population changes are good indicators of long-term and large-scale change in marine ecosystems, and important because of their many impacts on marine ecosystems. We assessed the population trend of the world’s monitored seabirds (1950–2010) by compiling a global database of seabird population size records and applying multivariate autoregressive state-space (MARSS) modeling to estimate the overall population trend of the portion of the population with sufficient data (i.e., at least five records). This monitored population represented approximately 19% of the global seabird population. We found the monitored portion of the global seabird population to have declined overall by 69.7% between 1950 and 2010. This declining trend may reflect the global seabird population trend, given the large and apparently representative sample. Furthermore, the largest declines were observed in families containing wide-ranging pelagic species, suggesting that pan-global populations may be more at risk than shorter-ranging coastal populations. PMID:26058068

  15. Seasonality of Ankle Swelling: Population Symptom Reporting Using Google Trends.

    PubMed

    Liu, Fangwei; Allan, G Michael; Korownyk, Christina; Kolber, Michael; Flook, Nigel; Sternberg, Harvey; Garrison, Scott

    2016-07-01

    In our experience, complaints of ankle swelling are more common in summer, typically from patients with no obvious cardiovascular disease. Surprisingly, this observation has never been reported. To objectively establish this phenomenon, we sought evidence of seasonality in the public's Internet searches for ankle swelling. Our data, obtained from Google Trends, consisted of all related Google searches in the United States from January 4, 2004, to January 26, 2016. Consistent with our expectations and confirmed by similar data for Australia, Internet searches for information on ankle swelling are highly seasonal (highest in midsummer), with seasonality explaining 86% of search volume variability. PMID:27401424

  16. MULTIPLE STRESSOR RISKS TO COMMON LOON AND OTHER PISCIVOROUS BIRD POPULATIONS

    EPA Science Inventory

    Mercury contamination remains a high priority issue for several EPA Program Offices andRegions because of widespread atmospheric deposition and concerns of accumulation through aquatic food webs. Although there is evidence of reduced productivity in some piscivorous birds and wid...

  17. North American Breeding Bird Survey annual summary 1990-1991

    USGS Publications Warehouse

    Peterjohn, B.G.; Sauer, J.R.

    1993-01-01

    The North American Breeding Bird Survey (BBS) was used to estimate continental and regional changes in bird populations during 1989-1990 and 1990-1991, placing these short-term changes within the context of population trends since 1966. For the entire survey area, 51.7% of the species exhibited increases in population size during 1989-1990, reversing the decreasing tendency exhibited by the majority of species during 1988-1989. A similar percentage (51.4%) of species with increasing populations was noted during 1990-1991. These percentages were also analyzed for 12 guilds of North American birds and 3 broad geographical regions. Many regional patterns exist in these population changes, reflecting the variability inherent in short-term population fluctuations. Two-year (1989-1990 and 1990-1991) changes and long-term (1966-1990) continental trends are provided for 255 species.

  18. State of Washington Population Trends, 1975. Washington State Information Report.

    ERIC Educational Resources Information Center

    Washington State Office of Program Planning and Fiscal Management, Olympia.

    As of April 1, 1975, Washington's population was estimated at 3,494,124--an increase of 80,874 since 1970. Prepared yearly, this report presents tabular data pertaining to: (1) current April 1 estimates for cities, towns, and counties; (2) current decline in household size; (3) the use of postal vacancy surveys in estimating vacancy rates; and (4)…

  19. Interpreting population estimates of birds following pesticide applications--behavior of male starlings exposed to an organophosphate pesticide

    USGS Publications Warehouse

    Grue, C.E.; Shipley, B.J.

    1981-01-01

    We determined activity budgets for 10 pairs of captive male Starlings between 7 May and 18 July 1980. Our objective was to quantify changes in behavior after exposure to an organophosphate (OP) pesticide and to assess the impact of changes in behavior on the interpretation of population estimates of birds following pesticide applications. We observed each pair of males for an hour at 07:30 and 09:30 for four days and classified their behavior into one of four categories: flying, perching, foraging, or singing and displaying. At 06:30 on day 2, one male received a single oral dose of 2.5 mg dicrotophos (3-hydroxy-N, N-dimethyl-cis-crotonamide dimethyl phosphate) per kg of body weight; the other male received an equivalent exposure of corn oil. Changes in the activity budgets of OP-dosed and control males were compared using t-tests. Activity of OP-dosed males was significantly (P _ 0.05) reduced within the 2-4 h following exposure. OP-dosed males spent more time perching (46.1%) than controls and less time flying (-96.6%), foraging (-28.5%), and singing and displaying (-49.5%). The frequency of perching (-75.3%), flying (-83.8%), foraging (-54.1%), and singing and displaying (- 59.2%) was significantly reduced. Activity in OP-dosed males returned to normal by 26-28 h posttreatment. Results suggest that movement and vocalization may be significantly reduced in birds exposed to organophosphate and carbamate pesticides. Conventional censusing techniques and population estimating procedures may, therefore, be inadequate to assess changes in bird populations after pesticide applications because of the difficulty in separating decreases in density due to mortality or emigration from reductions in activity.

  20. On the importance of controlling for effort in analysis of count survey data: Modeling population change from Christmas Bird Count data

    USGS Publications Warehouse

    Link, W.A.; Sauer, J.R.

    1999-01-01

    Count survey data are commonly used for estimating temporal and spatial patterns of population change. Since count surveys are not censuses, counts can be influenced by 'nuisance factors' related to the probability of detecting animals but unrelated to the actual population size. The effects of systematic changes in these factors can be confounded with patterns of population change. Thus, valid analysis of count survey data requires the identification of nuisance factors and flexible models for their effects. We illustrate using data from the Christmas Bird Count (CBC), a midwinter survey of bird populations in North America. CBC survey effort has substantially increased in recent years, suggesting that unadjusted counts may overstate population growth (or understate declines). We describe a flexible family of models for the effect of effort, that includes models in which increasing effort leads to diminishing returns in terms of the number of birds counted.

  1. Organohalogen exposure in a Eurasian Eagle owl (Bubo bubo) population from Southeastern Spain: temporal-spatial trends and risk assessment.

    PubMed

    Gómez-Ramírez, P; Martínez-López, E; García-Fernández, A J; Zweers, A J; van den Brink, N W

    2012-08-01

    Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine insecticides (OCs) were analysed in 58 Eurasian Eagle owl (Bubo bubo) unhatched eggs collected between 2004 and 2009 in Southeastern Spain. Levels of p,p'-DDE were found to be higher than in eggs laid by other European owls in the same decade, probably due to the greater agricultural activity in our study area. Compared to other European raptors, exposure to PCBs can be considered intermediate, but low to PBDEs. Land use differences and prey availability were the rationale to divide the study area in two subareas in further assessments. Temporal trends of HCB, p,p'-DDE, β-HCH, PCBs and PBDEs were significantly different in each subarea, generally increasing over time in the Southern but decreasing or remaining stable in the Northern. On the contrary, levels of cyclodienes tended to decrease in both subareas. Dietary shifts with a greater amount of birds are suggested as a cause for increasing organochlorine loads in raptors. This may explain the increasing trend in the Southern territories. However, due to the proximity of most of these nests to Cartagena, an important industrial city, increasing environmental pollution cannot be ruled out. Although average levels of the compounds analysed are below threshold levels, 17% of the samples exceeded 400 pg g(-1)ww (wet weight), the LOAEC for Total TEQs. Moreover, a negative correlation between TEQ concentrations and the metabolizable fraction of PCBs (F(prob)=0.0018) was found when TEQs values were above 10 pg g(-1)ww. This could be indicative of hepatic enzymes induction in the birds exposed at higher concentrations, which are mainly breeding in the Southern subarea. These females could be suffering from Ah-receptor-related toxic effects, some of which have been related to altered bird reproduction. Finally, a significant negative correlation between p,p'-DDE levels and eggshell thickness (r=-0.469, p<0.001) was observed, with

  2. [Macroeconomic recovery trends. Urban impact on the population].

    PubMed

    Perez Mendoza, J S

    1991-12-01

    Some reflections are presented on the impact of Mexico's macroeconomic policy on population dynamics and urban development in the immediate future as the opening and liberalization of the economic increasingly influence market forces. Although the actions envisaged in the macroeconomic policy are not yet consolidated, it is possible to foresee some of their consequences for the city and for population movement. It can be predicted that the macroeconomic policy will lead to greater economic growth and consolidation of the urban population because of positive expectations for stability and growth, and the resultant environment of confidence in the immediate future. A resurgence of private investment in goods and services directed primarily to private consumption will inevitable create demand for public investment in infrastructure and improved services. Demand for consumer durables in likely to rise, as is demand for housing. New residential zones are likely to appear and grow, changing the territorial configuration of urban areas. The urban administration should make some effort to control the growth. PMID:12317225

  3. Combining waterfowl and breeding bird survey data to estimate wood duck breeding population size in the Atlantic Flyway

    USGS Publications Warehouse

    Guthrie Zimmerman; Sauer, John; Fleming, Kathy; Link, William; Pamela R. Garrettson

    2015-01-01

    We combined data from the Atlantic Flyway Breeding Waterfowl Survey (AFBWS) and the North American Breeding Bird Survey (BBS) to estimate the number of wood ducks (Aix sponsa) in the United States portion of the Atlantic Flyway from 1993 to 2013. The AFBWS is a plot-based survey that covers most of the northern and central portions of the Flyway; when analyzed with adjustments for survey time of day effects, these data can be used to estimate population size. The BBS provides an index of wood duck abundance along roadside routes. Although factors influencing change in BBS counts over time can be controlled in BBS analysis, BBS indices alone cannot be used to derive population size estimates. We used AFBWS data to scale BBS indices for Bird Conservation Regions (BCR), basing the scaling factors on the ratio of estimated AFBWS population sizes to regional BBS indices for portions of BCRs that were common to both surveys. We summed scaled BBS results for portions of the Flyway not covered by the AFBWS with AFBWS population estimates to estimate a mean yearly total of 1,295,875 (mean 95% CI: 1,013,940–1,727,922) wood ducks. Scaling factors varied among BCRs from 16.7 to 148.0; the mean scaling factor was 68.9 (mean 95% CI: 53.5–90.9). Flyway-wide, population estimates from the combined analysis were consistent with alternative estimates derived from harvest data, and also provide population estimates within states and BCRs. We recommend their use in harvest and habitat management within the Atlantic Flyway.

  4. Abundance, distribution, and population trends of the iconic Hawaiian Honeycreeper, the ʻIʻiwi (Vestiaria coccinea) throughout the Hawaiian Islands

    USGS Publications Warehouse

    Paxton, Eben H.; Gorresen, P. Marcos; Camp, Richard J.

    2013-01-01

    Naturalists in the 1800s described the ʻIʻiwi (Vestiaria coccinea) as one of the most abundant forest birds, detected in forested areas from sea level to tree line across all the major Hawaiian Islands. However, in the late 1800s, ʻIʻiwi began to disappear from low elevation forests, and by the mid-1900s, the species was largely absent from low- and mid-elevation areas. Today, ʻIʻiwi are restricted to high-elevation forests on the islands of Hawaiʻi, east Maui, and Kauaʻi, with a few birds apparently persisting on Oʻahu, Molokaʻi, and west Maui. ʻIʻiwi are highly vulnerable to introduced disease, and the prevalence of avian malaria in low and mid-elevations is believed to be the cause of ʻIʻiwi being restricted to high elevations where temperatures are too cold for the development of the disease and its mosquito vector. With global warming, it is feared that the disease will move quickly into the high-elevation forests where the last ʻIʻiwi reside, threatening their viability. The U.S. Fish and Wildlife Service was petitioned to list the ʻIʻiwi as an Endangered Species in 2010, and this report provides a comprehensive review of the abundance, distribution, and trends using historical survey data as well as the most recently available survey information (up to 2012). We estimate the total population size of ‘I‘iwi at 550,972–659,864 (mean = 605,418) individuals. Of these, 90 percent are on the island of Hawaiʻi, followed by east Maui (about 10 percent), with less than 1 percent on Kauaʻi. ʻIʻiwi population trends vary across the islands. ʻIʻiwi population in Kauaʻi has experienced sharp declines, with a projected trend of 92 percent decline over a 25 year period based on the 2000–2012 surveys. On East Maui, the northeastern region has experienced declines (34 percent over a 25 year period), while the southeastern region has been stable to moderately increasing. On the island of Hawaiʻi, population trends are mixed. On the windward

  5. Monitoring trends in bat populations of the United States and territories: Problems and prospects

    USGS Publications Warehouse

    2003-01-01

    Bats are ecologically and economically important mammals. The life histories of bats (particularly their low reproductive rates and the need for some species to gather in large aggregations at limited numbers of roosting sites) make their populations vulnerable to declines. Many of the species of bats in the United States (U.S.) and territories are categorized as endangered or threatened, have been candidates for such categories, or are considered species of concern. The importance and vulnerability of bat populations makes monitoring trends in their populations a goal for their future management. However, scientifically rigorous monitoring of bat populations requires well-planned, statistically defensible efforts. This volume reports findings of an expert workshop held to examine the topic of monitoring populations of bats. The workshop participants included leading experts in sampling and analysis of wildlife populations, as well as experts in the biology and conservation of bats. Findings are reported in this volume under two sections. Part I of the report presents contributed papers that provide overviews of past and current efforts at monitoring trends in populations of bats in the U.S. and territories. These papers consider current techniques and problems, and summarize what is known about the status and trends in populations of selected groups of bats. The contributed papers in Part I also include a description of the monitoring program developed for bat populations in the United Kingdom, a critique of monitoring programs in wildlife in general with recommendations for survey and sampling strategies, and a compilation and analysis of existing data on trends in bats of the U.S. and territories. Efforts directed at monitoring bat populations are piecemeal and have shortcomings. In Part II of the report, the workshop participants provide critical analyses of these problems and develop recommendations for improving methods, defining objectives and priorities

  6. The role of selection and historical factors in driving population differentiation along an elevational gradient in an island bird.

    PubMed

    Bertrand, J A M; Delahaie, B; Bourgeois, Y X C; Duval, T; García-Jiménez, R; Cornuault, J; Pujol, B; Thébaud, C; Milá, B

    2016-04-01

    Adaptation to local environmental conditions and the range dynamics of populations can influence evolutionary divergence along environmental gradients. Thus, it is important to investigate patterns of both phenotypic and genetic variations among populations to reveal the respective roles of these two types of factors in driving population differentiation. Here, we test for evidence of phenotypic and genetic structure across populations of a passerine bird (Zosterops borbonicus) distributed along a steep elevational gradient on the island of Réunion. Using 11 microsatellite loci screened in 401 individuals from 18 localities distributed along the gradient, we found that genetic differentiation occurred at two spatial levels: (i) between two main population groups corresponding to highland and lowland areas, respectively, and (ii) within each of these two groups. In contrast, several morphological traits varied gradually along the gradient. Comparison of neutral genetic differentiation (FST ) and phenotypic differentiation (PST ) showed that PST largely exceeds FST at several morphological traits, which is consistent with a role for local adaptation in driving morphological divergence along the gradient. Overall, our results revealed an area of secondary contact midway up the gradient between two major, cryptic, population groups likely diverged in allopatry. Remarkably, local adaptation has shaped phenotypic differentiation irrespective of population history, resulting in different patterns of variation along the elevational gradient. Our findings underscore the importance of understanding both historical and selective factors when trying to explain variation along environmental gradients. PMID:26779843

  7. Accounting for Imperfect Detection Is Critical for Inferring Marine Turtle Nesting Population Trends

    PubMed Central

    Pfaller, Joseph B.; Bjorndal, Karen A.; Chaloupka, Milani; Williams, Kristina L.; Frick, Michael G.; Bolten, Alan B.

    2013-01-01

    Assessments of population trends based on time-series counts of individuals are complicated by imperfect detection, which can lead to serious misinterpretations of data. Population trends of threatened marine turtles worldwide are usually based on counts of nests or nesting females. We analyze 39 years of nest-count, female-count, and capture-mark-recapture (CMR) data for nesting loggerhead turtles (Caretta caretta) on Wassaw Island, Georgia, USA. Annual counts of nests and females, not corrected for imperfect detection, yield significant, positive trends in abundance. However, multistate open robust design modeling of CMR data that accounts for changes in imperfect detection reveals that the annual abundance of nesting females has remained essentially constant over the 39-year period. The dichotomy could result from improvements in surveys or increased within-season nest-site fidelity in females, either of which would increase detection probability. For the first time in a marine turtle population, we compare results of population trend analyses that do and do not account for imperfect detection and demonstrate the potential for erroneous conclusions. Past assessments of marine turtle population trends based exclusively on count data should be interpreted with caution and re-evaluated when possible. These concerns apply equally to population assessments of all species with imperfect detection. PMID:23638041

  8. Population trend of the Yellowstone grizzly bear as estimated from reproductive and survival rates

    USGS Publications Warehouse

    Eberhardt, L. L.; Blanchard, B. M.; Knight, R. R.

    1993-01-01

    The trend of the Yellowstone grizzly bear (Ursus arctos horribilis) population was estimated using reproductive rates calculated from 22 individual females and survival rates from 400 female bear-years. The point estimate of the rate of increase was 4.6%, with 95% confidence limits of 0 and 9%. Caution in interpreting this result is advised because of possible biases in the population parameter estimates. The main prospects for improving present knowledge of the population trend appear to be further study of possible biases in the parameter estimates, and the continued use of radiotelemetry to increase the number of samples on which the estimates are based.

  9. Developing indicators for European birds

    PubMed Central

    Gregory, Richard D; van Strien, Arco; Vorisek, Petr; Gmelig Meyling, Adriaan W; Noble, David G; Foppen, Ruud P.B; Gibbons, David W

    2005-01-01

    The global pledge to deliver ‘a significant reduction in the current rate of biodiversity loss by 2010’ is echoed in a number of regional and national level targets. There is broad consensus, however, that in the absence of conservation action, biodiversity will continue to be lost at a rate unprecedented in the recent era. Remarkably, we lack a basic system to measure progress towards these targets and, in particular, we lack standard measures of biodiversity and procedures to construct and assess summary statistics. Here, we develop a simple classification of biodiversity indicators to assist their development and clarify purpose. We use European birds, as example taxa, to show how robust indicators can be constructed and how they can be interpreted. We have developed statistical methods to calculate supranational, multi-species indices using population data from national annual breeding bird surveys in Europe. Skilled volunteers using standardized field methods undertake data collection where methods and survey designs differ slightly across countries. Survey plots tend to be widely distributed at a national level, covering many bird species and habitats with reasonable representation. National species' indices are calculated using log-linear regression, which allows for plot turnover. Supranational species' indices are constructed by combining the national species' indices weighted by national population sizes of each species. Supranational, multi-species indicators are calculated by averaging the resulting indices. We show that common farmland birds in Europe have declined steeply over the last two decades, whereas woodland birds have not. Evidence elsewhere shows that the main driver of farmland bird declines is increased agricultural intensification. We argue that the farmland bird indicator is a useful surrogate for trends in other elements of biodiversity in this habitat. PMID:15814345

  10. A Study of the Effects of Gas Well Compressor Noise on Breeding Bird Populations of the Rattlesnake Canyon Habitat Management Area, San Juan County, New Mexico

    SciTech Connect

    LaGory, K.E.; Chang, Young-Soo; Chun, K.C.; Reeves, T.; Liebich, R.; Smith, K.

    2001-06-04

    This report, conducted from May through July 2000, addressed the potential effect of compressor noise on breeding birds in gas-production areas administered by the FFO, specifically in the Rattlesnake Canyon Habitat Management Area northeast of Farmington, New Mexico. The study was designed to quantify and characterize noise output from these compressors and to determine if compressor noise affected bird populations in adjacent habitat during the breeding season.

  11. Persistence of an extreme male-biased adult sex ratio in a natural population of polyandrous bird.

    PubMed

    Kosztolányi, A; Barta, Z; Küpper, C; Székely, T

    2011-08-01

    In a number of insects, fishes and birds, the conventional sex roles are reversed: males are the main care provider, whereas females focus on matings. The reversal of typical sex roles is an evolutionary puzzle, because it challenges the foundations of sex roles, sexual selection and parental investment theory. Recent theoretical models predict that biased parental care may be a response to biased adult sex ratios (ASRs). However, estimating ASR is challenging in natural populations, because males and females often have different detectabilities. Here, we use demographic modelling with field data from 2101 individuals, including 579 molecularly sexed offspring, to provide evidence that ASR is strongly male biased in a polyandrous bird with male-biased care. The model predicts 6.1 times more adult males than females (ASR=0.860, proportion of males) in the Kentish plover Charadrius alexandrinus. The extreme male bias is consistent between years and concordant with experimental results showing strongly biased mating opportunity towards females. Based on these results, we conjecture that parental sex-role reversal may occur in populations that exhibit extreme male-biased ASR. PMID:21749544

  12. Temporal and latitudinal trends of p,p'-DDE in eggs and carcasses of North American birds from 1980 to 2005.

    PubMed

    Mora, Miguel A; Durgin, Bryce; Hudson, Lacy B; Jones, Edward

    2016-06-01

    The use of 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane (DDT) in agriculture in the United States and Canada was prohibited in the early 1970s; however, it continued to be used restrictively in Mexico until 2000. Forty years later, 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p'-DDE), continues to be detected in eggs and bird carcasses in North America. The use of DDE has been associated with reproductive failure of several avian species, primarily through eggshell thinning. To assess the temporal and latitudinal distribution of p,p'-DDE in North America, the authors examined DDE concentrations reported in bird tissues in the scientific literature published between 1980 and 2009. Overall, the majority of supported models suggested that DDE concentrations in birds were greater in the upper mid-latitudes (38°-48°) than in other parts of North America. However, spatial trends of DDE seemed to be influenced by regions with large amounts of data, such as the Great Lakes area. Concentrations of p,p'-DDE in eggs averaged 2.5 μg/g, 3.2 μg/g, and 29.5 μg/g wet weight in 1980 and decreased to 1.64 μg/g, 0.87 μg/g, and 1.01 μg/g wet weight by the mid-2000s for the central, eastern, and western North America regions, respectively. The results indicate that, over time, all DDE residues observed in birds have decreased significantly in North America. Environ Toxicol Chem 2016;35:1340-1348. © 2016 SETAC. PMID:26753749

  13. Recent population trends of mountain goats in the Olympic Mountains, Washington

    USGS Publications Warehouse

    Jenkins, Kurt J.; Happe, Patricia J.; Beirne, Katherine F.; Hoffman, Roger A.; Griffin, Paul C.; Baccus, William T.; Fieberg, John

    2012-01-01

    Mountain goats (Oreamnos americanus) were introduced in Washington's Olympic Mountains during the 1920s. The population subsequently increased in numbers and expanded in range, leading to concerns by the 1970s over the potential effects of non-native mountain goats on high-elevation plant communities in Olympic National Park. The National Park Service (NPS) transplanted mountain goats from the Olympic Mountains to other ranges between 1981 and 1989 as a means to manage overabundant populations, and began monitoring population trends of mountain goats in 1983. We estimated population abundance of mountain goats during 18–25 July 2011, the sixth survey of the time series, to assess current population status and responses of the population to past management. We surveyed 39 sample units, comprising 39% of the 59,615-ha survey area. We estimated a population of 344 ± 72 (90% confidence interval [CI]) mountain goats in the survey area. Retrospective analysis of the 2004 survey, accounting for differences in survey area boundaries and methods of estimating aerial detection biases, indicated that the population increased at an average annual rate of 4.9% since the last survey. That is the first population growth observed since the cessation of population control measures in 1990. We postulate that differences in population trends observed in western, eastern, and southern sections of the survey zone reflected, in part, a variable influence of climate change across the precipitation gradient in the Olympic Mountains.

  14. [Spatial distribution characteristics of urban potential population in Shenyang City based on QuickBird image and GIS].

    PubMed

    Li, Jun-Ying; Hu, Yuan-Man; Chen, Wei; Liu, Miao; Hu, Jian-Bo; Zhong, Qiao-Lin; Lu, Ning

    2012-06-01

    Population is the most active factor affecting city development. To understand the distribution characteristics of urban population is of significance for making city policy decisions and for optimizing the layout of various urban infrastructures. In this paper, the information of the residential buildings in Shenyang urban area was extracted from the QuickBird remote sensing images, and the spatial distribution characteristics of the population within the Third-Ring Road of the City were analyzed, according to the social and economic statistics data. In 2010, the population density in different types of residential buildings within the Third-Ring Road of the City decreased in the order of high-storey block, mixed block, mixed garden, old multi-storey building, high-storey garden, multi-storey block, multi-storey garden, villa block, shanty, and villa garden. The vacancy rate of the buildings within the Third-Ring Road was more than 30%, meaning that the real estate market was seriously overstocked. Among the five Districts of Shenyang City, Shenhe District had the highest potential population density, while Tiexi District and Dadong District had a lower one. The gravity center of the City and its five Districts was also analyzed, which could provide basic information for locating commercial facilities and planning city infrastructure. PMID:22937656

  15. Long-term consequences of high incubation temperature in a wild bird population.

    PubMed

    Nord, Andreas; Nilsson, Jan-Åke

    2016-04-01

    Because incubation by birds is energetically costly, parents frequently trade off investment in incubation against self-maintenance. This can be manifested by a reduction in incubation temperature, which comes at high somatic costs for nestlings. The extent to which these costs constrain fitness is poorly understood. We incubated wild blue tit clutches at three biologically relevant temperatures and subsequently recorded winter survival and survival to the breeding season. Fledglings from the coldest treatment (35.0°C) survived less well than other fledglings, but the proportion of winter and breeding survivors did not differ significantly between treatments. However, survival probability in both seasons increased with body mass at fledging in birds from low and mid incubation temperatures, but decreased with fledging body mass in the high-temperature treatment. Mid-temperature nestlings were heavier as adults, weighing 7% more than low- and high-temperature survivors. Thus, high incubation temperature can be beneficial in the short term, but costs of accelerated embryonic development may equal those of protracted development in the long term. Such hidden consequences of faster development could maintain natural selection for average incubation temperature. PMID:27048468

  16. VizieR Online Data Catalog: Stellar population trends in S0 galaxies (Chamberlain+, 2011)

    NASA Astrophysics Data System (ADS)

    Chamberlain, L. C. P.; Courteau, S.; McDonald, M.; Rose, J. A.

    2011-09-01

    We present stellar population age and metallicity trends for a sample of 59 S0 galaxies based on optical Sloan Digital Sky Survey (SDSS) and near-infrared (NIR) J and H photometry. When combined with optical g and r passband imaging data from the SDSS archive and stellar population models, we obtain radial age and metallicity trends out to at least five effective radii for most of the galaxies in our sample. The sample covers a range in stellar mass and light concentration. (6 data files).

  17. Long-term trends in first arrival and first egg laying dates of some migrant and resident bird species in northern Italy

    NASA Astrophysics Data System (ADS)

    Rubolini, Diego; Ambrosini, Roberto; Caffi, Mario; Brichetti, Pierandrea; Armiraglio, Stefano; Saino, Nicola

    2007-08-01

    Climate change is affecting the phenology of seasonal events in Europe and the Northern Hemisphere, as shown by several studies of birds’ timing of migration and reproduction. Here, we analyse the long-term (1982-2006) trends of first arrival dates of four long-distance migratory birds [swift ( Apus apus), nightingale ( Luscinia megarhynchos), barn swallow ( Hirundo rustica), and house martin ( Delichon urbicum)] and first egg laying dates of two migrant (swift, barn swallow) and two resident species [starling ( Sturnus vulgaris), Italian sparrow ( Passer italiae)] at a study site in northern Italy. We also addressed the effects of local weather (temperature and precipitation) and a climate index (the North Atlantic Oscillation, NAO) on the interannual variability of phenological events. We found that the swift and the barn swallow significantly advanced both arrival and laying dates, whereas all other species did not show any significant temporal trend in either arrival or laying date. The earlier arrival of swifts was explained by increasing local temperatures in April, whereas this was not the case for arrival dates of swallows and first egg laying dates of both species. In addition, arrival dates of house martins were earlier following high NAO winters, while nightingale arrival was earlier when local spring rainfall was greater. Finally, Italian sparrow onset of reproduction was anticipated by greater spring rainfall, but delayed by high spring NAO anomalies, and swift’s onset of reproduction was anticipated by abundant rainfall prior to reproduction. There were no significant temporal trends in the interval between onset of laying and arrival in either the swift or the barn swallow. Our findings therefore indicate that birds may show idiosyncratic responses to climate variability at different spatial scales, though some species may be adjusting their calendar to rapidly changing climatic conditions.

  18. A statistical assessment of population trends for data deficient Mexican amphibians.

    PubMed

    Quintero, Esther; Thessen, Anne E; Arias-Caballero, Paulina; Ayala-Orozco, Bárbara

    2014-01-01

    Background. Mexico has the world's fifth largest population of amphibians and the second country with the highest quantity of threatened amphibian species. About 10% of Mexican amphibians lack enough data to be assigned to a risk category by the IUCN, so in this paper we want to test a statistical tool that, in the absence of specific demographic data, can assess a species' risk of extinction, population trend, and to better understand which variables increase their vulnerability. Recent studies have demonstrated that the risk of species decline depends on extrinsic and intrinsic traits, thus including both of them for assessing extinction might render more accurate assessment of threats. Methods. We harvested data from the Encyclopedia of Life (EOL) and the published literature for Mexican amphibians, and used these data to assess the population trend of some of the Mexican species that have been assigned to the Data Deficient category of the IUCN using Random Forests, a Machine Learning method that gives a prediction of complex processes and identifies the most important variables that account for the predictions. Results. Our results show that most of the data deficient Mexican amphibians that we used have decreasing population trends. We found that Random Forests is a solid way to identify species with decreasing population trends when no demographic data is available. Moreover, we point to the most important variables that make species more vulnerable for extinction. This exercise is a very valuable first step in assigning conservation priorities for poorly known species. PMID:25548736

  19. A statistical assessment of population trends for data deficient Mexican amphibians

    PubMed Central

    Thessen, Anne E.; Arias-Caballero, Paulina; Ayala-Orozco, Bárbara

    2014-01-01

    Background. Mexico has the world’s fifth largest population of amphibians and the second country with the highest quantity of threatened amphibian species. About 10% of Mexican amphibians lack enough data to be assigned to a risk category by the IUCN, so in this paper we want to test a statistical tool that, in the absence of specific demographic data, can assess a species’ risk of extinction, population trend, and to better understand which variables increase their vulnerability. Recent studies have demonstrated that the risk of species decline depends on extrinsic and intrinsic traits, thus including both of them for assessing extinction might render more accurate assessment of threats. Methods. We harvested data from the Encyclopedia of Life (EOL) and the published literature for Mexican amphibians, and used these data to assess the population trend of some of the Mexican species that have been assigned to the Data Deficient category of the IUCN using Random Forests, a Machine Learning method that gives a prediction of complex processes and identifies the most important variables that account for the predictions. Results. Our results show that most of the data deficient Mexican amphibians that we used have decreasing population trends. We found that Random Forests is a solid way to identify species with decreasing population trends when no demographic data is available. Moreover, we point to the most important variables that make species more vulnerable for extinction. This exercise is a very valuable first step in assigning conservation priorities for poorly known species. PMID:25548736

  20. Large-scale control site selection for population monitoring: an example assessing Sage-grouse trends

    USGS Publications Warehouse

    Fedy, Bradley C.; O'Donnell, Michael; Bowen, Zachary H.

    2015-01-01

    Human impacts on wildlife populations are widespread and prolific and understanding wildlife responses to human impacts is a fundamental component of wildlife management. The first step to understanding wildlife responses is the documentation of changes in wildlife population parameters, such as population size. Meaningful assessment of population changes in potentially impacted sites requires the establishment of monitoring at similar, nonimpacted, control sites. However, it is often difficult to identify appropriate control sites in wildlife populations. We demonstrated use of Geographic Information System (GIS) data across large spatial scales to select biologically relevant control sites for population monitoring. Greater sage-grouse (Centrocercus urophasianus; hearafter, sage-grouse) are negatively affected by energy development, and monitoring of sage-grouse population within energy development areas is necessary to detect population-level responses. Weused population data (1995–2012) from an energy development area in Wyoming, USA, the Atlantic Rim Project Area (ARPA), and GIS data to identify control sites that were not impacted by energy development for population monitoring. Control sites were surrounded by similar habitat and were within similar climate areas to the ARPA. We developed nonlinear trend models for both the ARPA and control sites and compared long-term trends from the 2 areas. We found little difference between the ARPA and control sites trends over time. This research demonstrated an approach for control site selection across large landscapes and can be used as a template for similar impact-monitoring studies. It is important to note that identification of changes in population parameters between control and treatment sites is only the first step in understanding the mechanisms that underlie those changes. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  1. Signature of a Pre-Human Population Decline in the Critically Endangered Reunion Island Endemic Forest Bird Coracina newtoni

    PubMed Central

    Salmona, Jordi; Salamolard, Marc; Fouillot, Damien; Ghestemme, Thomas; Larose, Jerry; Centon, Jean-François; Sousa, Vitor; Dawson, Deborah A.; Thebaud, Christophe; Chikhi, Lounès

    2012-01-01

    The exceptional biodiversity of Reunion Island is threatened by anthropogenic landscape changes that took place during the 350 years of human colonization. During this period the human population size increased dramatically from 250 to 800,000. The arrival of humans together with the development of agriculture, invasive species such as rats and cats, and deforestation has lead to the extinction of more than half of the original vertebrate species of the island. For the remaining species, significant work is being carried out to identify threats and conservation status, but little genetic work has been carried on some of the most endangered species. In the last decade theoretical studies have shown the ability of neutral genetic markers to infer the demographic history of endangered species and identify and date past population size changes (expansions or bottlenecks). In this study we provide the first genetic data on the critically endangered species the Reunion cuckoo-shrike Coracina newtoni. The Reunion cuckoo-shrike is a rare endemic forest bird surviving in a restricted 12-km2 area of forested uplands and mountains. The total known population consists of less than one hundred individuals out of which 45 were genotyped using seventeen polymorphic microsatellite loci. We found a limited level of genetic variability and weak population structure, probably due to the limited geographic distribution. Using Bayesian methods, we identified a strong decline in population size during the Holocene, most likely caused by an ancient climatic or volcanic event around 5000 years ago. This result was surprising as it appeared in apparent contradiction with the accepted theory of recent population collapse due to deforestation and predator introduction. These results suggest that new methods allowing for more complex demographic models are necessary to reconstruct the demographic history of populations. PMID:22916272

  2. The Bird.

    ERIC Educational Resources Information Center

    Hannon, Jean

    2001-01-01

    Students use a dead bird to learn about bird life, anatomy, and death. Students examine a bird body and discuss what happened to the bird. Uses outdoor education as a resource for learning about animals. (SAH)

  3. Bird Flu

    MedlinePlus

    ... viruses infect birds, including chickens, other poultry, and wild birds such as ducks. Most bird flu viruses ... become sick. It may also be possible to catch bird flu by eating poultry or eggs that ...

  4. Effects of lek count protocols on greater sage-grouse population trend estimates

    USGS Publications Warehouse

    Monroe, Adrian; Edmunds, David; Aldridge, Cameron

    2016-01-01

    Annual counts of males displaying at lek sites are an important tool for monitoring greater sage-grouse populations (Centrocercus urophasianus), but seasonal and diurnal variation in lek attendance may increase variance and bias of trend analyses. Recommendations for protocols to reduce observation error have called for restricting lek counts to within 30 minutes of sunrise, but this may limit the number of lek counts available for analysis, particularly from years before monitoring was widely standardized. Reducing the temporal window for conducting lek counts also may constrain the ability of agencies to monitor leks efficiently. We used lek count data collected across Wyoming during 1995−2014 to investigate the effect of lek counts conducted between 30 minutes before and 30, 60, or 90 minutes after sunrise on population trend estimates. We also evaluated trends across scales relevant to management, including statewide, within Working Group Areas and Core Areas, and for individual leks. To further evaluate accuracy and precision of trend estimates from lek count protocols, we used simulations based on a lek attendance model and compared simulated and estimated values of annual rate of change in population size (λ) from scenarios of varying numbers of leks, lek count timing, and count frequency (counts/lek/year). We found that restricting analyses to counts conducted within 30 minutes of sunrise generally did not improve precision of population trend estimates, although differences among timings increased as the number of leks and count frequency decreased. Lek attendance declined >30 minutes after sunrise, but simulations indicated that including lek counts conducted up to 90 minutes after sunrise can increase the number of leks monitored compared to trend estimates based on counts conducted within 30 minutes of sunrise. This increase in leks monitored resulted in greater precision of estimates without reducing accuracy. Increasing count

  5. Long-Term Trends and Role of Climate in the Population Dynamics of Eurasian Reindeer.

    PubMed

    Uboni, Alessia; Horstkotte, Tim; Kaarlejärvi, Elina; Sévêque, Anthony; Stammler, Florian; Olofsson, Johan; Forbes, Bruce C; Moen, Jon

    2016-01-01

    Temperature is increasing in Arctic and sub-Arctic regions at a higher rate than anywhere else in the world. The frequency and nature of precipitation events are also predicted to change in the future. These changes in climate are expected, together with increasing human pressures, to have significant impacts on Arctic and sub-Arctic species and ecosystems. Due to the key role that reindeer play in those ecosystems, it is essential to understand how climate will affect the region's most important species. Our study assesses the role of climate on the dynamics of fourteen Eurasian reindeer (Rangifer tarandus) populations, using for the first time data on reindeer abundance collected over a 70-year period, including both wild and semi-domesticated reindeer, and covering more than half of the species' total range. We analyzed trends in population dynamics, investigated synchrony among population growth rates, and assessed the effects of climate on population growth rates. Trends in the population dynamics were remarkably heterogeneous. Synchrony was apparent only among some populations and was not correlated with distance among population ranges. Proxies of climate variability mostly failed to explain population growth rates and synchrony. For both wild and semi-domesticated populations, local weather, biotic pressures, loss of habitat and human disturbances appear to have been more important drivers of reindeer population dynamics than climate. In semi-domesticated populations, management strategies may have masked the effects of climate. Conservation efforts should aim to mitigate human disturbances, which could exacerbate the potentially negative effects of climate change on reindeer populations in the future. Special protection and support should be granted to those semi-domesticated populations that suffered the most because of the collapse of the Soviet Union, in order to protect the livelihood of indigenous peoples that depend on the species, and the multi

  6. Long-Term Trends and Role of Climate in the Population Dynamics of Eurasian Reindeer

    PubMed Central

    Horstkotte, Tim; Kaarlejärvi, Elina; Sévêque, Anthony; Stammler, Florian; Olofsson, Johan; Forbes, Bruce C.; Moen, Jon

    2016-01-01

    Temperature is increasing in Arctic and sub-Arctic regions at a higher rate than anywhere else in the world. The frequency and nature of precipitation events are also predicted to change in the future. These changes in climate are expected, together with increasing human pressures, to have significant impacts on Arctic and sub-Arctic species and ecosystems. Due to the key role that reindeer play in those ecosystems, it is essential to understand how climate will affect the region’s most important species. Our study assesses the role of climate on the dynamics of fourteen Eurasian reindeer (Rangifer tarandus) populations, using for the first time data on reindeer abundance collected over a 70-year period, including both wild and semi-domesticated reindeer, and covering more than half of the species’ total range. We analyzed trends in population dynamics, investigated synchrony among population growth rates, and assessed the effects of climate on population growth rates. Trends in the population dynamics were remarkably heterogeneous. Synchrony was apparent only among some populations and was not correlated with distance among population ranges. Proxies of climate variability mostly failed to explain population growth rates and synchrony. For both wild and semi-domesticated populations, local weather, biotic pressures, loss of habitat and human disturbances appear to have been more important drivers of reindeer population dynamics than climate. In semi-domesticated populations, management strategies may have masked the effects of climate. Conservation efforts should aim to mitigate human disturbances, which could exacerbate the potentially negative effects of climate change on reindeer populations in the future. Special protection and support should be granted to those semi-domesticated populations that suffered the most because of the collapse of the Soviet Union, in order to protect the livelihood of indigenous peoples that depend on the species, and the multi

  7. Climate-driven fluctuation of a wild bird population over the past half millennium

    NASA Astrophysics Data System (ADS)

    Naef-Daenzer, B.; Luterbacher, J.; Nuber, M.; Rutishauser, Th.; Winkel, W.

    2009-04-01

    Mechanisms underlying climate-driven changes in ecosystem structure and function are poorly understood because hardly any ecological records start before the recent warming phase. We analyse an exceptional 100-year record of the great tit population (Parus major) and habitat phenology in Switzerland, and model climate-driven population fluctuations since AD 1500. Additional to high plasticity of the system, we find a significant influence of the large-scale atmospheric circulation (North-Atlantic Oscillation) on fitness-relevant life history traits and population dynamics. The multidecadal circulation impact resulted in low fecundity and population minima during the ‘Maunder Minimum' (1650-1720) and the Little Ice Age Type Event I (1810-1850), whereas the warming since 1975 is related with the highest productivity since 1500 and an unprecedented increase of the population.

  8. The European and Japanese outbreaks of H5N8 derive from a single source population providing evidence for the dispersal along the long distance bird migratory flyways

    PubMed Central

    Iqbal, Munir

    2015-01-01

    The origin of recent parallel outbreaks of the high pathogenicity H5N8 avian flu virus in Europe and in Japan can be traced to a single source population, which has most likely been spread by migratory birds. By using Bayesian coalescent methods to analyze the DNA sequences of the virus to find the times for divergence and combining this sequence data with bird migration data we can show the most likely locations and migratory pathways involved in the origin of the current outbreak. This population was most likely located in the Siberian summer breeding grounds of long-range migratory birds. These breeding grounds provide a connection between different migratory flyways and explain the current outbreaks in remote locations. By combining genetic methods and epidemiological data we can rapidly identify the sources and the dispersion pathways for novel avian influenza outbreaks. PMID:25945320

  9. The relative roles of cultural drift and acoustic adaptation in shaping syllable repertoires of island bird populations change with time since colonization.

    PubMed

    Potvin, Dominique A; Clegg, Sonya M

    2015-02-01

    In birds, song divergence often precedes and facilitates divergence of other traits. We assessed the relative roles of cultural drift, innovation, and acoustic adaptation in divergence of island bird dialects, using silvereyes (Zosterops lateralis). In recently colonized populations, syllable diversity was not significantly lower than source populations, shared syllables between populations decreased with increasing number of founder events, and dialect variation displayed contributions from both habitat features and drift. The breadth of multivariate space occupied by recently colonized Z. l. lateralis populations was comparable to evolutionarily old forms that have diverged over thousands to hundreds of thousands of years. In evolutionarily old subspecies, syllable diversity was comparable to the mainland and the amount of variation in syllable composition explained by habitat features increased by two- to threefold compared to recently colonized populations. Together these results suggest that cultural drift influences syllable repertoires in recently colonized populations, but innovation likely counters syllable loss from colonization. In evolutionarily older populations, the influence of acoustic adaptation increases, possibly favoring a high diversity of syllables. These results suggest that the relative importance of cultural drift and acoustic adaptation changes with time since colonization in island bird populations, highlighting the value of considering multiple mechanisms and timescale of divergence when investigating island song divergence. PMID:25496402

  10. Repeated inseminations required for natural fertility in a wild bird population.

    PubMed Central

    Török, János; Michl, Gábor; Garamszegi, László Zs; Barna, Judit

    2003-01-01

    In most bird species, pairs copulate many times before egg laying. The exact function of repeated inseminations (i.e. successful copulations) is unknown, but several suggestions have been made. We tested the hypothesis that repeated inseminations are required to ensure fertilization of eggs, by using an experimental method where free-ranging male collared flycatchers (Ficedula albicollis) were prevented from inseminating their mates. We show that egg fertility was lower when females had not copulated during the studied part of their fertile period. By counting sperm on the inner perivitelline layer of eggs, we estimated that a minimum of 86 sperm must reach the site of fertilization to ensure average fertility. Using the timing of inseminations and the numbers of sperm on successive eggs, we show that repeated copulations are necessary to achieve an average rate of fertilization of a single clutch. Our results thus provide evidence that repeated inseminations function to ensure fertilization success. We discuss possible constraints on sperm production and utilization that may have contributed to this pattern. PMID:12769465

  11. Distribution, diversity and drivers of blood-borne parasite co-infections in Alaskan bird populations.

    PubMed

    Oakgrove, Khouanchy S; Harrigan, Ryan J; Loiseau, Claire; Guers, Sue; Seppi, Bruce; Sehgal, Ravinder N M

    2014-09-01

    Avian species are commonly infected by multiple parasites, however few studies have investigated the environmental determinants of the prevalence of co-infection over a large scale. Here we believe that we report the first, detailed ecological study of the prevalence, diversity and co-infections of four avian blood-borne parasite genera: Plasmodium spp., Haemoproteus spp., Leucocytozoon spp. and Trypanosoma spp. We collected blood samples from 47 resident and migratory bird species across a latitudinal gradient in Alaska. From the patterns observed at collection sites, random forest models were used to provide evidence of associations between bioclimatic conditions and the prevalence of parasite co-infection distribution. Molecular screening revealed a higher prevalence of haematozoa (53%) in Alaska than previously reported. Leucocytozoons had the highest diversity, prevalence and prevalence of co-infection. Leucocytozoon prevalence (35%) positively correlated with Trypanosoma prevalence (11%), negatively correlated with Haemoproteus prevalence (14%) and had no correlation with Plasmodium prevalence (7%). We found temperature, precipitation and tree cover to be the primary environmental drivers that show a relationship with the prevalence of co-infection. The results provide insight into the impacts of bioclimatic drivers on parasite ecology and intra-host interactions, and have implications for the study of infectious diseases in rapidly changing environments. PMID:25014331

  12. Population structure and demographic trends of the registered Sahiwal cattle in Kenya.

    PubMed

    Kamiti, Duncan; Ilatsia, Evans; Bett, Rawlynce; Kahi, Alexander

    2016-06-01

    Sahiwal cattle breed is an important genetic resource that supports livelihoods of pastoralists in Kenya. However, information about its population structure, demographic trends, and genetic diversity is scarce. The objective of this study was to characterize the population structure, explore demographic trends, and evaluate genetic diversity parameters of the breed through pedigree analysis. Pedigree data from National Sahiwal Stud and Kenya Stud Book were combined and analyzed using POPREP software package. The number of registered breeding animals indicated a downward trend over time. Generation interval was longer by 3 years in males than in females. Average inbreeding coefficient was 0.58 % for all animals and 2.23 % for inbred animals. Average inbreeding between 1960 and 2008 for inbred animals decreased at -0.0012 % per year while for the entire breed increased at 0.025 % per year. Additive genetic relationship in the whole population was 0.87 %. The effective population size declined over time and was lower than that recommended to maintain genetic diversity in the long term. The breed was found to be losing genetic diversity over time, and therefore a strategy to reduce inbreeding rate and increase effective population size is recommended. PMID:27085712

  13. Restricted dispersal reduces the strength of spatial density dependence in a tropical bird population

    PubMed Central

    Burgess, Malcolm D; Nicoll, Malcolm A.C; Jones, Carl G; Norris, Ken

    2008-01-01

    Spatial processes could play an important role in density-dependent population regulation because the disproportionate use of poor quality habitats as population size increases is widespread in animal populations—the so-called buffer effect. While the buffer effect patterns and their demographic consequences have been described in a number of wild populations, much less is known about how dispersal affects distribution patterns and ultimately density dependence. Here, we investigated the role of dispersal in spatial density dependence using an extraordinarily detailed dataset from a reintroduced Mauritius kestrel (Falco punctatus) population with a territorial (despotic) breeding system. We show that recruitment rates varied significantly between territories, and that territory occupancy was related to its recruitment rate, both of which are consistent with the buffer effect theory. However, we also show that restricted dispersal affects the patterns of territory occupancy with the territories close to release sites being occupied sooner and for longer as the population has grown than the territories further away. As a result of these dispersal patterns, the strength of spatial density dependence is significantly reduced. We conclude that restricted dispersal can modify spatial density dependence in the wild, which has implications for the way population dynamics are likely to be impacted by environmental change. PMID:18285284

  14. Population size and trend of Yellow-billed Loons in northern Alaska

    USGS Publications Warehouse

    Earnst, Susan L.; Stehn, R.A.; Platte, Robert; Larned, W.W.; Mallek, E.J.

    2005-01-01

    The Yellow-billed Loon (Gavia adamsii) is of conservation concern due to its restricted range, small population size, specific habitat requirements, and perceived threats to its breeding and wintering habitat. Within the U.S., this species breeds almost entirely within the National Petroleum Reserve-Alaska, nearly all of which is open, or proposed to be opened, for oil development. Rigorous estimates of Yellow-billed Loon population size and trend are lacking but essential for informed conservation. We used two annual aerial waterfowl surveys, conducted 1986a??2003 and 1992a??2003, to estimate population size and trend on northern Alaskan breeding grounds. In estimating population trend, we used mixed-effects regression models to reduce bias and sampling error associated with improvement in observer skill and annual effects of spring phenology. The estimated population trend on Alaskan breeding grounds since 1986 was near 0 with an estimated annual change of a??0.9% (95% CI of a??3.6% to +1.8%). The estimated population size, averaged over the past 12 years and adjusted by a correction factor based on an intensive, lake-circling, aerial survey method, was 2221 individuals (95% CI of 1206a??3235) in early June and 3369 individuals (95% CI of 1910a??4828) in late June. Based on estimates from other studies of the proportion of loons nesting in a given year, it is likely that <1000 nesting pairs inhabit northern Alaska in most years. The highest concentration of Yellow-billed Loons occurred between the Meade and Ikpikpuk Rivers; and across all of northern Alaska, 53% of recorded sightings occurred within 12% of the area.

  15. Survey trends of North American shorebirds: Population declines or shifting distributions?

    USGS Publications Warehouse

    Bart, J.; Brown, S.; Harrington, B.; Morrison, R.I. Guy

    2007-01-01

    We analyzed data from two surveys of fall migrating shorebirds in central and eastern North America to estimate annual trends in means per survey and to determine whether trends indicate a change in population size or might have been caused by other factors. The analysis showed a broad decline in means per survey in Atlantic Canada and the northeastern United States (North Atlantic region). For example, 9 of 9 significant trends in this region were <1 (P=0.004), and the mean, annual rate of change among 30 species was 0.9783, a decline of -2.17% per year (P<0.001). Trends in the midwestern United States (Midwest region) showed no clear pattern. The mean among 29 species was 1.0090 (P=0.35). Only 4 of the trends were significant. Several hypotheses were evaluated to identify causes of the declining means per survey in the North Atlantic region. The most likely hypothesis appears to be a decline in the breeding populations that supply migrants to the North Atlantic region, but a change in movements, for example passing through the region more quickly in recent years, cannot be excluded as an explanation. Further surveys of arctic breeding areas coupled with analysis of long-term survey data from western North America would be helpful in determining whether the declines found in this analysis are also occurring in other areas. ?? Journal of Avian Biology.

  16. The New Population Debate: Two Views on Population Growth and Economic Development. Population Trends and Public Policy, Number 7.

    ERIC Educational Resources Information Center

    King, Timothy; Kelley, Allen C.

    Articles representing two views on the issue of rapid population growth and economic development are presented. Although the authors present different perspectives, they agree on many of the fundamentals. For example, both reject alarmism about impending "population explosions" and the use of population as a scapegoat for all Third World ills.…

  17. Environmental and genetic determinants of innovativeness in a natural population of birds.

    PubMed

    Quinn, John L; Cole, Ella F; Reed, Thomas E; Morand-Ferron, Julie

    2016-03-19

    Much of the evidence for the idea that individuals differ in their propensity to innovate and solve new problems has come from studies on captive primates. Increasingly, behavioural ecologists are studying innovativeness in wild populations, and uncovering links with functional behaviour and fitness-related traits. The relative importance of genetic and environmental factors in driving this variation, however, remains unknown. Here, we present the results of the first large-scale study to examine a range of causal factors underlying innovative problem-solving performance (PSP) among 831 great tits (Parus major) temporarily taken into captivity. Analyses show that PSP in this population: (i) was linked to a variety of individual factors, including age, personality and natal origin (immigrant or local-born); (ii) was influenced by natal environment, because individuals had a lower PSP when born in poor-quality habitat, or where local population density was high, leading to cohort effects. Links with many of the individual and environmental factors were present only in some years. In addition, PSP (iii) had little or no measurable heritability, as estimated by a Bayesian animal model; and (iv) was not influenced by maternal effects. Despite previous reports of links between PSP and a range of functional traits in this population, the analyses here suggest that innovativeness had weak if any evolutionary potential. Instead most individual variation was caused by phenotypic plasticity driven by links with other behavioural traits and by environmentally mediated developmental stress. Heritability estimates are population, time and context specific, however, and more studies are needed to determine the generality of these effects. Our results shed light on the causes of innovativeness within populations, and add to the debate on the relative importance of genetic and environmental factors in driving phenotypic variation within populations. PMID:26926275

  18. Hierarchical models and Bayesian analysis of bird survey information

    USGS Publications Warehouse

    Sauer, J.R.; Link, W.A.; Royle, J. Andrew

    2005-01-01

    Summary of bird survey information is a critical component of conservation activities, but often our summaries rely on statistical methods that do not accommodate the limitations of the information. Prioritization of species requires ranking and analysis of species by magnitude of population trend, but often magnitude of trend is a misleading measure of actual decline when trend is poorly estimated. Aggregation of population information among regions is also complicated by varying quality of estimates among regions. Hierarchical models provide a reasonable means of accommodating concerns about aggregation and ranking of quantities of varying precision. In these models the need to consider multiple scales is accommodated by placing distributional assumptions on collections of parameters. For collections of species trends, this allows probability statements to be made about the collections of species-specific parameters, rather than about the estimates. We define and illustrate hierarchical models for two commonly encountered situations in bird conservation: (1) Estimating attributes of collections of species estimates, including ranking of trends, estimating number of species with increasing populations, and assessing population stability with regard to predefined trend magnitudes; and (2) estimation of regional population change, aggregating information from bird surveys over strata. User-friendly computer software makes hierarchical models readily accessible to scientists.

  19. Candidate gene–environment interactions and their relationships with timing of breeding in a wild bird population

    PubMed Central

    Bourret, Audrey; Garant, Dany

    2015-01-01

    Monitoring and predicting evolutionary changes underlying current environmental modifications are complex challenges. Recent approaches to achieve these objectives include assessing the genetic variation and effects of candidate genes on traits indicating adaptive potential. In birds, for example, short tandem repeat polymorphism at four candidate genes (CLOCK, NPAS2, ADCYAP1, and CREB1) has been linked to variation in phenological traits such as laying date and timing of migration. However, our understanding of their importance as evolutionary predictors is still limited, mainly because the extent of genotype–environment interactions (GxE) related to these genes has yet to be assessed. Here, we studied a population of Tree swallow (Tachycineta bicolor) over 4 years in southern Québec (Canada) to assess the relationships between those four candidate genes and two phenological traits related to reproduction (laying date and incubation duration) and also determine the importance of GxE in this system. Our results showed that NPAS2 female genotypes were nonrandomly distributed across the study system and formed a longitudinal cline with longer genotypes located to the east. We observed relationships between length polymorphism at all candidate genes and laying date and/or incubation duration, and most of these relationships were affected by environmental variables (breeding density, latitude, or temperature). In particular, the positive relationships detected between laying date and both CLOCK and NPAS2 female genotypes were variable depending on breeding density. Our results suggest that all four candidate genes potentially affect timing of breeding in birds and that GxE are more prevalent and important than previously reported in this context. PMID:26380692

  20. Trends in the treatment of alcohol problems in the US general population, 1979 through 1990.

    PubMed Central

    Weisner, C; Greenfield, T; Room, R

    1995-01-01

    OBJECTIVES. The purpose of this study was to conduct a comprehensive analysis of alcohol-treatment service utilization trends in the general population during the 1980s. METHODS. Three national surveys of the US household population (1979, 1984, and 1990) were used for trend analysis of treatment utilization. Trends in demographic characteristics of persons with lifetime treatment rates and particular types of treatment were examined by means of logistic regression analysis, controlling for alcohol problem severity and other variables. RESULTS. Substantial increases in the numbers reporting treatment were found. In all surveys, Alcoholics Anonymous was the treatment used most frequently and its use increased most, especially for women. Men were more likely than women (odds ratio [OR] = 2.01, 95% confidence interval [CI] = 1.20, 5.39) and unmarried persons were twice as likely as married persons to have been treated [corrected]. Social consequences carried more predictive power than dependence symptoms. CONCLUSIONS. From a general population perspective, while overall treatment capacity has increased, the structural changes in the public/private balance of services have not positively affected the representation of women or other characteristics of the treatment population. PMID:7832262

  1. Population Change, Resources, and the Environment. Population Trends and Public Policy No. 4.

    ERIC Educational Resources Information Center

    Jacobsen, Judith, Ed.

    Intended for policymakers, this document focuses on environmental factors limiting the expansion of the world's food supply, the dilemma of fostering third world economic development, and prospects for energy development. The first of five parts gives an overview of a 1983 Population Reference Bureau conference which focused on current thinking…

  2. Influence of habitat amount, arrangement, and use on population trend estimates of male Kirtland's warblers

    USGS Publications Warehouse

    Donner, D.M.; Probst, J.R.; Ribic, C.A.

    2008-01-01

    Kirtland's warblers (Dendroica kirtlandii) persist in a naturally patchy environment of young, regenerating jack pine forests (i.e., 5-23 years old) created after wildfires and human logging activities. We examined how changing landscape structure from 26 years of forest management and wildfire disturbances influenced population size and spatial dispersion of male Kirtland's warblers within their restricted breeding range in northern Lower Michigan, USA. The male Kirtland's warbler population was six times larger in 2004 (1,322) compared to 1979 (205); the change was nonlinear with 1987 and 1994 identified as significant points of change. In 1987, the population trend began increasing after a slowly declining trend prior to 1987, and the rate of increase appeared to slow after 1994. Total amount of suitable habitat and the relative area of wildfire-regenerated habitat were the most important factors explaining population trend. Suitable habitat increased 149% primarily due to increasing plantations from forest management. The relative amount and location of wildfire-regenerated habitat modified the distribution of males among various habitat types, and the spatial variation in their abundance across the primary breeding range. These findings indicate that the Kirtland's warbler male population shifted its use of habitat types temporally and spatially as the population increased and as the relative availability of habitats changed through time. We demonstrate that researchers and managers need to consider not only habitat quality, but the temporal and the spatial context of habitat availability and population levels when making habitat restoration decisions. ?? 2008 Springer Science+Business Media B.V.

  3. Causes, trends, and policy of population migration and the floating population.

    PubMed

    Cai, F

    1996-01-01

    This study provides a discussion of migration theory, a description of the main characteristics of migrants and floating population in China, and a migration impact assessment and potential social policy directions. It is argued that the impetus for migration in China was the population distribution pattern and an uneven industrial structure that favored heavy industry. Another factor affecting migration is the gap in income between urban and rural areas, which has widened since reforms in the mid-1980s. The author finds the Todaro or the Harris-Todaro theories inappropriate for understanding migration in developing countries and flawed. Evidence about migrants' characteristics suggest that migration in China was part of a process governed by the laws of economic growth and market development. Legal migrants are defined as those who legally migrated according to the household registration system. China's development strategy during the 1950s relied on growth of capital-intensive heavy industry. The cost was underwritten by adoption of a price system that shifted the price of products in order to lower the cost of heavy industrial development. During 1952-78, agricultural output dropped sharply, but the employment structure changed very little and the rate of urbanization changed slightly. Regional inequality was obvious by 1978. As reform progressed, patterns emerged that favored eastern coastal development. Microlevel reform outdistanced macrolevel reform. Obstacles to migration were reduced: the breakup of the commune system and changes in the urban food supply system and housing. In 1990 there were 34.128 million migrants, of which 32.42% were interprovincial and 42.99% involved job-related shifts. In 1992, 8.1% of urban population were not registered; 94.909 million were floating population. Cities have established policies to match the size of the floating population to the current carrying capacity. PMID:12291970

  4. Temporal trends of perfluoroalkyl substances (PFAS) in eggs of coastal and offshore birds: Increasing PFAS levels associated with offshore bird species breeding on the Pacific coast of Canada and wintering near Asia.

    PubMed

    Miller, Aroha; Elliott, John E; Elliott, Kyle H; Lee, Sandi; Cyr, Francois

    2015-08-01

    Perfluoroalkyl substances (PFAS) such as perfluoroalkyl carboxylates (PFCAs) and perfluoroalkyl sulfonates (PFSAs) have become virtually ubiquitous throughout the environment, and, based on laboratory studies, have known toxicological consequences. Various national and international voluntary phase-outs and restrictions on these compounds have been implemented over the last 10 to 15 years. In the present study, we examine trends (1990/1991-2010/2011) in aquatic birds (ancient murrelet, Synthliboramphus antiquus [2009 only]; Leach's storm-petrels, Oceanodroma leucorhoa; rhinoceros auklets, Cerorhinca monocerata; double-crested cormorants, Phalacrocorax auritus; and great blue herons, Ardea herodias). The PFCA, PFSA, and stable isotope (δ(15) N and δ(13) C) data collected from these species from the Pacific coast of Canada, ranging over 20 to 30 years, were used to investigate temporal changes in PFAS coupled to dietary changes. Perfluorooctane sulfonic acid (PFOS), the dominant PFSA compound in all 4 species, increased and subsequently decreased in auklet and cormorant eggs in line with the manufacturing phase-out of PFOS and perfluorooctanoic acid (PFOA), but concentrations continuously increased in petrel eggs and remained largely unchanged in heron eggs. Dominant PFCA compounds varied between the offshore and coastal species, with increases seen in the offshore species and little or variable changes seen in the coastal species. Little temporal change was seen in stable isotope values, indicating that diet alone is not driving observed PFAS concentrations. PMID:25989421

  5. Heritability of fear of humans in urban and rural populations of a bird species.

    PubMed

    Carrete, Martina; Martínez-Padilla, Jesús; Rodríguez-Martínez, Sol; Rebolo-Ifrán, Natalia; Palma, Antonio; Tella, José L

    2016-01-01

    Flight initiation distance (FID), a measure of an animal's tolerance to human disturbance and a descriptor of its fear of humans, is increasingly employed for conservation purposes and to predict the response of species to urbanization. However, most work devoted to understanding variability in FID has been conducted at the population level and little is still known about inter-individual variability in this behaviour. We estimated the heritability of FID, a factor fundamental to understanding the strength and evolutionary consequences of selection of particular phenotypes associated with human disturbances. We used a population of burrowing owls (Athene cunicularia) monitored long-term and for which FID was previously shown to be highly consistent across an individual's lifespan. Heritability estimates varied between 0.37 and 0.80, depending on the habitat considered (urban-rural) and method used (parent-offspring regressions or animal models). These values are unusually high compared with those previously reported for other behavioural traits. Although more research is needed to fully understand the underlying causes of this resemblance between relatives, selection pressures acting on this behaviour should be seriously considered as an important evolutionary force in animal populations increasingly exposed to human disturbance worldwide. PMID:27499420

  6. Heritability of fear of humans in urban and rural populations of a bird species

    PubMed Central

    Carrete, Martina; Martínez-Padilla, Jesús; Rodríguez-Martínez, Sol; Rebolo-Ifrán, Natalia; Palma, Antonio; Tella, José L.

    2016-01-01

    Flight initiation distance (FID), a measure of an animal’s tolerance to human disturbance and a descriptor of its fear of humans, is increasingly employed for conservation purposes and to predict the response of species to urbanization. However, most work devoted to understanding variability in FID has been conducted at the population level and little is still known about inter-individual variability in this behaviour. We estimated the heritability of FID, a factor fundamental to understanding the strength and evolutionary consequences of selection of particular phenotypes associated with human disturbances. We used a population of burrowing owls (Athene cunicularia) monitored long-term and for which FID was previously shown to be highly consistent across an individual’s lifespan. Heritability estimates varied between 0.37 and 0.80, depending on the habitat considered (urban-rural) and method used (parent-offspring regressions or animal models). These values are unusually high compared with those previously reported for other behavioural traits. Although more research is needed to fully understand the underlying causes of this resemblance between relatives, selection pressures acting on this behaviour should be seriously considered as an important evolutionary force in animal populations increasingly exposed to human disturbance worldwide. PMID:27499420

  7. Agriculture modifies the seasonal decline of breeding success in a tropical wild bird population

    PubMed Central

    Cartwright, Samantha J; Nicoll, Malcolm A C; Jones, Carl G; Tatayah, Vikash; Norris, Ken

    2014-01-01

    Habitat conversion for agriculture is a major driver of biodiversity loss, but our understanding of the demographic processes involved remains poor. We typically investigate the impacts of agriculture in isolation even though populations are likely to experience multiple, concurrent changes in the environment (e.g. land and climate change). Drivers of environmental change may interact to affect demography, but the mechanisms have yet to be explored fully in wild populations. Here, we investigate the mechanisms linking agricultural land use with breeding success using long-term data for the formerly Critically Endangered Mauritius kestrel Falco punctatus, a tropical forest specialist that also occupies agricultural habitats. We specifically focused on the relationship between breeding success, agriculture and the timing of breeding because the latter is sensitive to changes in climatic conditions (spring rainfall) and enables us to explore the interactive effects of different (land and climate) drivers of environmental change. Breeding success, measured as egg survival to fledging, declines seasonally in this population, but we found that the rate of this decline became increasingly rapid as the area of agriculture around a nest site increased. If the relationship between breeding success and agriculture was used in isolation to estimate the demographic impact of agriculture, it would significantly under-estimate breeding success in dry (early) springs and over-estimate breeding success in wet (late) springs. Analysis of prey delivered to nests suggests that the relationship between breeding success and agriculture might be due, in part, to spatial variation in the availability of native, arboreal geckos. Synthesis and applications. Agriculture modifies the seasonal decline in breeding success in this population. As springs are becoming wetter in our study area and since the kestrels breed later in wetter springs, the impact of agriculture on breeding success will

  8. Conflicting Readmission Rate Trends in a High-Risk Population: Implications for Performance Measurement

    PubMed Central

    Vann, Julie C. Jacobson; Jackson, Carlos T.

    2015-01-01

    Abstract The 30-day readmission rate is a common performance indicator for hospitals and accountable care entities. There is reason to question whether measuring readmissions as a function of hospital discharges is an appropriate measure of performance for initiatives that aim to improve overall cost and quality outcomes in a population. The objectives of this study were to compare trends in 30-day readmission rates per discharge to population-based measures of hospital admission and readmission frequency in a high-risk statewide Medicaid population over a 5-year period of quality improvement and care management intervention. Further, this study aimed to examine case-mix changes among hospitalized beneficiaries over time. This was a retrospective analysis of North Carolina Medicaid paid claims 2008 through 2012 for beneficiaries with multiple chronic or catastrophic conditions. Thirty-day readmission rates per discharge trended upward from 18.3% in 2008 to 18.7% in 2012. However, the rate of 30-day readmissions per 1000 beneficiaries declined from 123.3 to 110.7. Overall inpatient admissions per 1000 beneficiaries decreased from 579.4 to 518.5. The clinical complexity of hospitalized patients increased over the 5-year period. Although rates of hospital admissions and readmissions fell substantially in this high-risk population over 5 years, the 30-day readmission rate trend appeared unfavorable when measured as a percent of hospital discharges. This may be explained by more complex patients requiring hospitalization over time. The choice of metrics significantly affects the perceived effectiveness of improvement initiatives. Emphasis on readmission rates per discharge may be misguided for entities with a population health management focus. (Population Health Management 2015;18:351–357) PMID:25607449

  9. Fertility rates and future population trends: will Europe's birth rate recover or continue to decline?

    PubMed

    Lutz, Wolfgang

    2006-02-01

    Europe has long completed its demographic transition from high birth and death rates to low birth and death rates. But the demographic transition paradigm that has been very useful for explaining global demographic trends during the 20th century and that still has strong predictive power when it comes to projecting future trends in countries that still have high fertility, has nothing to say about the future of fertility in Europe. The currently popular notion of a 'second demographic transition' is a useful way to describe a bundle of behavioural and normative changes that recently happened in Europe, but it has no predictive power. The social sciences have not yet come up with a useful theory to predict the future fertility level of post-demographic transition societies. We even do not know whether the trend will be up or down. Given the lack of a predictive theory, this paper will try to do two things: (i) Summarize different substantive arguments that would either suggest the assumption of a recovery of fertility rates in Europe or alternatively, imply further declines. (ii) Convert this discussion of the uncertainty of future fertility trends into probabilistic population projections for Europe, thus highlighting the implications of alternative fertility levels over the coming years. We will also discuss trade-offs between fertility and immigration, and the phenomenon that Europe now has entered a period of negative momentum of population growth. PMID:16466521

  10. [Population trends and behavioral observations of wintering common cranes (Grus grus) in Yancheng Nature Reserve].

    PubMed

    Li, Zhong-Qiu; Wang, Zhi; Ge, Chen

    2013-10-01

    To understand the population status and behavioural features of wintering common cranes in the Yancheng Nature Reserve, two transects were established and population trends were monitored every month over five recent winters from 2008 to 2013. Wintering behaviours were also observed in order to explore the possible effects of family size and age on time budgets. Results indicated that the populations were stable with a range of 303 to 707 individuals. Negative effects of coastal developments were not found on the wintering population of common cranes, which might be related to their diets and preference for artificial wetland habitats. We found a significant effect of age on time budgets, with juveniles spending more time feeding and less time alerting, which might be related to the needs of body development and skill learning. Family size did not affect the time budgets of the cranes, which indicated that adults did not increase vigilance investment even when raising a larger family. PMID:24115655

  11. Individual variation in rates of senescence: natal origin effects and disposable soma in a wild bird population.

    PubMed

    Bouwhuis, Sandra; Charmantier, Anne; Verhulst, Simon; Sheldon, Ben C

    2010-11-01

    1. Longitudinal studies of various vertebrate populations have recently demonstrated senescent declines in reproductive performance and/or survival probability with age to be almost ubiquitous in nature. Little is known, however, about the extent to which rates of senescence vary between individuals, and about causes or consequences of such variation. Quantifying these links in natural populations is important for understanding the constraints and adaptive processes underlying the evolution of senescence. 2. Here, we analyse breeding data from 1029 female great tits Parus major to quantify the effect of natal conditions and early life reproduction on rates of reproductive senescence, reproductive life span and lifetime reproductive success. 3. Although for locally born females we find no evidence that natal conditions influence rates of reproductive senescence, we show that immigrant females suffer from faster rates of senescence than locally born females, and that this difference contributes to immigrants having a lower lifetime reproductive success. 4. Additionally, and independently, we find rates of reproductive senescence to increase with rates of early life reproduction, as predicted by the disposable soma hypothesis. Despite accelerated senescence late in life, high early life reproduction is, however, positively associated with lifetime reproductive success across individuals. 5. Female immigrant status and early life reproduction do not relate to reproductive life span. 6. We thus show that both immigration into our population, and high levels of early life reproduction, are associated with reduced late life reproductive performance in female great tits, but that fitness can be increased by high levels of early life reproduction at the expense of accelerated reproductive senescence. These results suggest disposable soma to be a likely mechanism underlying senescence in these birds, and encourage further study of the genetic basis (i.e. antagonistic

  12. Wild boar populations up, numbers of hunters down? A review of trends and implications for Europe.

    PubMed

    Massei, Giovanna; Kindberg, Jonas; Licoppe, Alain; Gačić, Dragan; Šprem, Nikica; Kamler, Jiří; Baubet, Eric; Hohmann, Ulf; Monaco, Andrea; Ozoliņš, Janis; Cellina, Sandra; Podgórski, Tomasz; Fonseca, Carlos; Markov, Nickolay; Pokorny, Boštjan; Rosell, Carme; Náhlik, András

    2015-04-01

    Across Europe, wild boar numbers increased in the 1960s-1970s but stabilised in the 1980s; recent evidence suggests that the numbers and impact of wild boar has grown steadily since the 1980s. As hunting is the main cause of mortality for this species, we reviewed wild boar hunting bags and hunter population trends in 18 European countries from 1982 to 2012. Hunting statistics and numbers of hunters were used as indicators of animal numbers and hunting pressure. The results confirmed that wild boar increased consistently throughout Europe, while the number of hunters remained relatively stable or declined in most countries. We conclude that recreational hunting is insufficient to limit wild boar population growth and that the relative impact of hunting on wild boar mortality had decreased. Other factors, such as mild winters, reforestation, intensification of crop production, supplementary feeding and compensatory population responses of wild boar to hunting pressure might also explain population growth. As populations continue to grow, more human-wild boar conflicts are expected unless this trend is reversed. New interdisciplinary approaches are urgently required to mitigate human-wild boar conflicts, which are otherwise destined to grow further. PMID:25512181

  13. Consequences of habitat change and resource selection specialization for population limitation in cavity-nesting birds

    USGS Publications Warehouse

    Martin, Thomas E.

    2015-01-01

    Synthesis and applications. Management should target species that specialize in resource selection on a declining resource. Species with greater resource selection generalization can reduce population impacts of environmental change. Resource generalization can allow a species like the wren to take advantage of habitat refuges, such as those provided by the elk exclosures. Yet, resource generalization cannot offset the negative impacts of broad-scale declines in habitat quality on the landscape, as demonstrated by the general decline of wrens. Ultimately, aspen is an important habitat for biodiversity, and land management programmes that protect and aid recovery of aspen habitats may be critical.

  14. Reconstructing the Phylogenetic History of Long-Term Effective Population Size and Life-History Traits Using Patterns of Amino Acid Replacement in Mitochondrial Genomes of Mammals and Birds

    PubMed Central

    Nabholz, Benoit; Lartillot, Nicolas

    2013-01-01

    The nearly neutral theory, which proposes that most mutations are deleterious or close to neutral, predicts that the ratio of nonsynonymous over synonymous substitution rates (dN/dS), and potentially also the ratio of radical over conservative amino acid replacement rates (Kr/Kc), are negatively correlated with effective population size. Previous empirical tests, using life-history traits (LHT) such as body-size or generation-time as proxies for population size, have been consistent with these predictions. This suggests that large-scale phylogenetic reconstructions of dN/dS or Kr/Kc might reveal interesting macroevolutionary patterns in the variation in effective population size among lineages. In this work, we further develop an integrative probabilistic framework for phylogenetic covariance analysis introduced previously, so as to estimate the correlation patterns between dN/dS, Kr/Kc, and three LHT, in mitochondrial genomes of birds and mammals. Kr/Kc displays stronger and more stable correlations with LHT than does dN/dS, which we interpret as a greater robustness of Kr/Kc, compared with dN/dS, the latter being confounded by the high saturation of the synonymous substitution rate in mitochondrial genomes. The correlation of Kr/Kc with LHT was robust when controlling for the potentially confounding effects of nucleotide compositional variation between taxa. The positive correlation of the mitochondrial Kr/Kc with LHT is compatible with previous reports, and with a nearly neutral interpretation, although alternative explanations are also possible. The Kr/Kc model was finally used for reconstructing life-history evolution in birds and mammals. This analysis suggests a fairly large-bodied ancestor in both groups. In birds, life-history evolution seems to have occurred mainly through size reduction in Neoavian birds, whereas in placental mammals, body mass evolution shows disparate trends across subclades. Altogether, our work represents a further step toward a more

  15. Impact of secular trends on sex assessment evaluated through femoral dimensions of the Czech population.

    PubMed

    Guyomarc'h, Pierre; Velemínská, Jana; Sedlak, Petr; Dobisíková, Miluše; Švenkrtová, Iva; Brůžek, Jaroslav

    2016-05-01

    Human skeletal variability is influenced by several factors, including genetics, environment, and socio-cultural background. Forensic methods being traditionally based on targeted reference groups, it is recognized that they are population-specific. Additionally, secular trends highly impact on the skeletal morphology, but the effect of outdated methods on forensic cases is not yet well documented. This paper compares the sexual dimorphism of femoral dimensions in two samples from the Czech population separated by 60 years in time (Pachner and the Prague National Museum Collections). Significant secular trends are present within this short span in both sexes and for most of the seven tested linear variables. The consequence of secular trends on sex determination is tested with logistic regression, and a decrease in reliability is systematically observed when using the older Czech sample on the 20th century sample, whichever the set of variables included. A model based on a recent Croatian sample provides a higher reliability on contemporaneous Czech individuals. These results imply that above population specificity, temporal consistency may be a major criterion to fulfil when applying forensic anthropology identification methods. PMID:26980521

  16. Neonatal body condition, immune responsiveness, and hematocrit predict longevity in a wild bird population

    PubMed Central

    Hodges, Christine J.; Forsman, Anna M.; Vogel, Laura A.; Masters, Brian S.; Johnson, Bonnie G. P.; Johnson, L. Scott; Thompson, Charles F.; Sakaluk, Scott K.

    2014-01-01

    Measures of body condition, immune function, and hematological health are widely used in ecological studies of vertebrate populations, predicated on the assumption that these traits are linked to fitness. However, compelling evidence that these traits actually predict long-term survival and reproductive success among individuals in the wild is lacking. Here, we show that body condition (i.e., size-adjusted body mass) and cutaneous immune responsiveness to phytohaemagglutinin (PHA) injection among neonates positively predict recruitment and subsequent longevity in a wild, migratory population of house wrens (Troglodytes aedon). However, neonates with intermediate hematocrit had the highest recruitment and longevity. Neonates with the highest PHA responsiveness and intermediate hematocrit prior to independence eventually produced the most offspring during their lifetime breeding on the study site. Importantly, the effects of PHA responsiveness and hematocrit were revealed while controlling for variation in body condition, sex, and environmental variation. Thus, our data demonstrate that body condition, cutaneous immune responsiveness, and hematocrit as a neonate are associated with individual fitness. Although hematocrit's effect is more complex than traditionally thought, our results suggest a previously underappreciated role for this trait in influencing survival in the wild. PMID:25505800

  17. Grizzly bear population vital rates and trend in the Northern Continental Divide Ecosystem, Montana

    USGS Publications Warehouse

    Mace, R.D.; Carney, D.W.; Chilton-Radandt, T.; Courville, S.A.; Haroldson, M.A.; Harris, R.B.; Jonkel, J.; McLellan, B.; Madel, M.; Manley, T.L.; Schwartz, C.C.; Servheen, C.; Stenhouse, G.; Waller, J.S.; Wenum, E.

    2012-01-01

    We estimated grizzly bear (Ursus arctos) population vital rates and trend for the Northern Continental Divide Ecosystem (NCDE), Montana, between 2004 and 2009 by following radio-collared females and observing their fate and reproductive performance. Our estimates of dependent cub and yearling survival were 0.612 (95% CI = 0.300–0.818) and 0.682 (95% CI = 0.258–0.898). Our estimates of subadult and adult female survival were 0.852 (95% CI = 0.628–0.951) and 0.952 (95% CI = 0.892–0.980). From visual observations, we estimated a mean litter size of 2.00 cubs/litter. Accounting for cub mortality prior to the first observations of litters in spring, our adjusted mean litter size was 2.27 cubs/litter. We estimated the probabilities of females transitioning from one reproductive state to another between years. Using the stable state probability of 0.322 (95% CI = 0.262–0.382) for females with cub litters, our adjusted fecundity estimate (mx) was 0.367 (95% CI = 0.273–0.461). Using our derived rates, we estimated that the population grew at a mean annual rate of approximately 3% (λ = 1.0306, 95% CI = 0.928–1.102), and 71.5% of 10,000 Monte Carlo simulations produced estimates of λ > 1.0. Our results indicate an increasing population trend of grizzly bears in the NCDE. Coupled with concurrent studies of population size, we estimate that over 1,000 grizzly bears reside in and adjacent to this recovery area. We suggest that monitoring of population trend and other vital rates using radioed females be continued.

  18. Trends in the growth of population and labour force in Pakistan.

    PubMed

    Hashmi, S S

    1990-01-01

    Trends in the growth of the population and labor force in Pakistan are examined and future prospects for growth of population and labor, particularly agriculture, are estimated. The definition of labor force as employed or seeking work after a short period of employment has led to a great disparity in results for women in the labor force. Past trends in population growth reflected a growth rate of 1.6% for the 1950's, and 2.4% in 1960. The population rose to 84.3 million in 1981 from 42.6 million in 1961, which intercensally was an increase of 3.6% per annum for 1961-72 and 3.1% per annum for 1972-81. The estimated rate for 1981-86 was 2.9%/year. The rural population doubled and the urban tripled. There was a net migration of 2.123 million to urban areas reported in the 1981 census. There is also evidence of a high sex ratio. Balochistan (7.1%) and Sindh (3.6%) provinces have the highest growth rates. Although the largest population is in the Punjab, the growth is the lowest at 2.7%. The population is primarily young -- 44.5% 15 years in 1981, which is the highest in the world. Under high, medium, and low levels of fertility, prospective trends are estimated for 2006 and 2031, and by sex every 5 years from 1981. Population under high fertility is expected to reach 270 million by 2031, which is 3.39 persons/hectare. The population/hectare of land under cultivation was 4.25 in 1981 and is expected to rise to 13.49 persons/hectare in 2031. 11 million acres could be brought under cultivation to reduce the ratio. However, there are ecological considerations as well as an employment problem. The dependency ratio under the high variant will decline from 76.8 persons 0-14 and 65 years/100 persons 15-64 years in 1986 to 70.3 in 2006 which is still considerably higher than other developing countries. It is suggested that replacement level fertility be attained as soon as possible. Under low fertility, replacement level can be reached by 2011 with strong political commitment

  19. Mhc supertypes confer both qualitative and quantitative resistance to avian malaria infections in a wild bird population

    PubMed Central

    Sepil, Irem; Lachish, Shelly; Hinks, Amy E.; Sheldon, Ben C.

    2013-01-01

    Major histocompatibility complex (Mhc) genes are believed to play a key role in the genetic basis of disease control. Although numerous studies have sought links between Mhc and disease prevalence, many have ignored the ecological and epidemiological aspects of the host–parasite interaction. Consequently, interpreting associations between prevalence and Mhc has been difficult, whereas discriminating alleles for qualitative resistance, quantitative resistance and susceptibility remains challenging. Moreover, most studies to date have quantified associations between genotypes and disease status, overlooking the complex relationship between genotype and the properties of the Mhc molecule that interacts with parasites. Here, we address these problems and demonstrate avian malaria (Plasmodium) parasite species-specific associations with functional properties of Mhc molecules (Mhc supertypes) in a wild great tit (Parus major) population. We further show that correctly interpreting these associations depends crucially on understanding the spatial variation in risk of infection and the fitness effects of infection. We report that a single Mhc supertype confers qualitative resistance to Plasmodium relictum, whereas a different Mhc supertype confers quantitative resistance to Plasmodium circumflexum infections. Furthermore, we demonstrate common functional properties of Plasmodium-resistance alleles in passerine birds, suggesting this is a model system for parasite–Mhc associations in the wild. PMID:23516242

  20. Disentangling the effect of genes, the environment and chance on sex ratio variation in a wild bird population.

    PubMed

    Postma, Erik; Heinrich, Franziska; Koller, Ursina; Sardell, Rebecca J; Reid, Jane M; Arcese, Peter; Keller, Lukas F

    2011-10-01

    Sex ratio theory proposes that the equal sex ratio typically observed in birds and mammals is the result of natural selection. However, in species with chromosomal sex determination, the same 1 : 1 sex ratio is expected under random Mendelian segregation. Here, we present an analysis of 14 years of sex ratio data for a population of song sparrows (Melospiza melodia) on Mandarte Island, at the nestling stage and at independence from parental care. We test for the presence of variance in sex ratio over and above the binomial variance expected under Mendelian segregation, and thereby quantify the potential for selection to shape sex ratio. Furthermore, if sex ratio variation is to be shaped by selection, we expect some of this extra-binomial variation to have a genetic basis. Despite ample statistical power, we find no evidence for the existence of either genetic or environmentally induced variation in sex ratio, in the nest or at independence. Instead, the sex ratio variation observed matches that expected under random Mendelian segregation. Using one of the best datasets of its kind, we conclude that female song sparrows do not, and perhaps cannot, adjust the sex of their offspring. We discuss the implications of this finding and make suggestions for future research. PMID:21345862

  1. Count trends for migratory Bald Eagles reveal differences between two populations at a spring site along the Lake Ontario shoreline.

    PubMed

    Wright, Kyle R

    2016-01-01

    The recovery of Bald Eagles (Haliaeetus leucophalus), after DDT and other organochlorine insecticides were banned in the United States, can be regarded as one of the most iconic success stories resulting from the Endangered Species Act. Interest remains high in the recovery and growth of the Bald Eagle population. Common to evaluating growth and recovery rates are counts at nesting sites and analyses of individuals fledged per season. But this is merely one snapshot that ignores survival rates as eagles grow to maturity. By analyzing indices from migration counts, we get a different snapshot better reflecting the survival of young birds. Different populations of Bald Eagles breed at different sites at different times of the year. Typical migration count analyses do not separate the populations. A separation of two distinct populations can be achieved at spring count sites by taking advantage of the tendency for northern summer breeding birds to migrate north in spring earlier than southern winter breeding birds who disperse north later in spring. In this paper I analyze migratory indices at a spring site along Lake Ontario. The analysis shows that eagles considered to be primarily of the northern summer breeding population showed an estimated growth rate of 5.3 ± 0.85% (SE) per year with 49% of eagles tallied in adult plumage, whereas the migrants considered to be primarily of the southern breeding population had an estimated growth rate of 14.0 ± 1.79% with only 22% in adult plumage. Together these results argue that the populations of southern breeding Bald Eagles are growing at a substantially higher rate than northern breeding eagles. These findings suggest that aggregate population indices for a species at migration counting sites can sometimes obscure important differences among separate populations at any given site and that separating counts by time period can be a useful way to check for differences among sub-populations. PMID:27231647

  2. Count trends for migratory Bald Eagles reveal differences between two populations at a spring site along the Lake Ontario shoreline

    PubMed Central

    2016-01-01

    The recovery of Bald Eagles (Haliaeetus leucophalus), after DDT and other organochlorine insecticides were banned in the United States, can be regarded as one of the most iconic success stories resulting from the Endangered Species Act. Interest remains high in the recovery and growth of the Bald Eagle population. Common to evaluating growth and recovery rates are counts at nesting sites and analyses of individuals fledged per season. But this is merely one snapshot that ignores survival rates as eagles grow to maturity. By analyzing indices from migration counts, we get a different snapshot better reflecting the survival of young birds. Different populations of Bald Eagles breed at different sites at different times of the year. Typical migration count analyses do not separate the populations. A separation of two distinct populations can be achieved at spring count sites by taking advantage of the tendency for northern summer breeding birds to migrate north in spring earlier than southern winter breeding birds who disperse north later in spring. In this paper I analyze migratory indices at a spring site along Lake Ontario. The analysis shows that eagles considered to be primarily of the northern summer breeding population showed an estimated growth rate of 5.3 ± 0.85% (SE) per year with 49% of eagles tallied in adult plumage, whereas the migrants considered to be primarily of the southern breeding population had an estimated growth rate of 14.0 ± 1.79% with only 22% in adult plumage. Together these results argue that the populations of southern breeding Bald Eagles are growing at a substantially higher rate than northern breeding eagles. These findings suggest that aggregate population indices for a species at migration counting sites can sometimes obscure important differences among separate populations at any given site and that separating counts by time period can be a useful way to check for differences among sub-populations. PMID:27231647

  3. The Future of the American Family [And] Prospective Trends in the Size and Structure of the Elderly Population, Impact of Mortality Trends, and Some Implications. Current Population Reports, Special Studies Series P-23, No. 78.

    ERIC Educational Resources Information Center

    Glick, Paul C.; Siegel, Jacob S.

    The document contains two reports on consequences of population trends for families and older adults in the United States. The reports were submitted as testimony before congressional committees on population and aging. The first report discusses projected changes in American family life in light of population growth, enrollment in schools and…

  4. Incidence trends of colorectal cancer in Iran during 2000-2009: A population-based study

    PubMed Central

    Abdifard, Edris; Amini, Sudabe; Bab, Sattar; Masroor, Nasim; Khachian, Alice; Heidari, Mohammad

    2016-01-01

    Background: As the third leading cause of death, cancers have a special place in the Iranian health system. Several studies have been done in some regions of the country with few years of follow-ups, but this was the first standardized study to investigate the incidence trends of colorectal cancer in Iran in a one-decade period. Methods: The registered data for colorectal cancer cases in National Cancer Registry System were extracted from the Center for Disease Control & Management of Ministry of Health. The codes from 18 to 21 among cancers were selected for colon and rectum cancers. Incidence rates were directly standardized, using WHO population. The significance of incidence rate trends was tested through Poisson regression. Results: In this study, 36,650 cases of colorectal cancer were observed for 10 years in Iran, which increased from 813 cases in 2000 to 6,210 cases in 2009. Gender ratio of men to women was 1.39. Significant increasing trends of colorectal cancer were observed during the period of the study. The standardized incidence rate increased from 1.6 per 100,000 persons per year in 2000 to 11.3 in 2009 in males (p<0.001), and it increased from 1.6 per 100,000 persons per year in 2000 to 10.9 in 2009 in females (p<0.001). Conclusion: Colorectal cancer has an increasing trend in Iran. The rising trend of colorectal cancer as well as other types of cancers is partially due to improvement in cancer registry systems in the early years of registry. Moreover, westernized lifestyle and an increase in environmental risks could explain this rising trend. PMID:27493926

  5. Tests for inbreeding and outbreeding depression and estimation of population differentiation in the bird-pollinated shrub Grevillea mucronulata

    PubMed Central

    N. Forrest, Cairo; Ottewell, Kym M.; Whelan, Robert J.; Ayre, David J.

    2011-01-01

    Background and Aims Plants show patterns of spatial genetic differentiation reflecting gene flow mediated by pollen and seed dispersal and genotype × environment interactions. If patterns of genetic structure are determined largely by gene flow then they may be useful in predicting the likelihood of inbreeding or outbreeding depression but should be less useful if there is strong site-specific selection. For many Australian plants little is known about either their population genetics or the effects on mating systems of variation in pollen transfer distances. Experimental pollinations were used to compare the reproductive success of bird-adapted Grevillea mucronulata plants mated with individuals from a range of spatial scales. A hierarchical survey of microsatellite DNA variation was also conducted to describe the scale of population differentiation for neutral markers. Methods The effects of four pollen treatments on reproductive performance were compared. These treatments were characterized by transfer of pollen from (a) neighbouring adults; (b) an adjacent cluster of adults (30–50 m distant); (c) a distant cluster (>5 km distant); and (d) open pollination. Sets of 17·9 ± 3·3 leaves from each of 15 clusters of plants were genotyped and spatial autocorrelation and F statistics were used to describe patterns of genetic structure. Key Results Grevillea mucronulata displayed evidence of both inbreeding and outbreeding depression, with ‘intermediate’ pollen producing consistently superior outcomes for most aspects of fitness including seed set, seed size, germination and seedling growth. Significant genotypic structuring was detected within clusters (spatial autocorrelation) and among adjacent clusters and clusters separated by >5 km distance (FST = 0·07 and 0·10). Conclusions The superior outcome of intermediate pollen transfer and genetic differentiation of adjacent clusters suggests that G. mucronulata selection disfavours matings among closely and

  6. Evaluation of New Technologies for Cancer Control Based on Population Trends in Disease Incidence and Mortality

    PubMed Central

    2013-01-01

    Cancer interventions often disseminate in the population before evidence of their effectiveness is available. Population disease trends provide a natural experiment for assessing the characteristics of the disease and the potential impact of the intervention. We review models for extracting information from population data for use in economic evaluations of cancer screening interventions. We focus particularly on prostate-specific antigen (PSA) screening for prostate cancer and describe approaches that can be used to project the likely costs and benefits of competing screening policies. Results indicate that the lifetime probability of biopsy-detectable prostate cancer is 33%, the chance of clinical diagnosis without screening is 13%, and the average time from onset to clinical diagnosis is 14 years. Less aggressive screening policies that screen less often and use more conservative criteria (e.g., higher PSA thresholds) for biopsy referral may dramatically reduce PSA screening costs with modest impact on benefit. PMID:23962515

  7. Combined Influences of Model Choice, Data Quality, and Data Quantity When Estimating Population Trends.

    PubMed

    Rueda-Cediel, Pamela; Anderson, Kurt E; Regan, Tracey J; Franklin, Janet; Regan, Helen M

    2015-01-01

    Estimating and projecting population trends using population viability analysis (PVA) are central to identifying species at risk of extinction and for informing conservation management strategies. Models for PVA generally fall within two categories, scalar (count-based) or matrix (demographic). Model structure, process error, measurement error, and time series length all have known impacts in population risk assessments, but their combined impact has not been thoroughly investigated. We tested the ability of scalar and matrix PVA models to predict percent decline over a ten-year interval, selected to coincide with the IUCN Red List criterion A.3, using data simulated for a hypothetical, short-lived organism with a simple life-history and for a threatened snail, Tasmaphena lamproides. PVA performance was assessed across different time series lengths, population growth rates, and levels of process and measurement error. We found that the magnitude of effects of measurement error, process error, and time series length, and interactions between these, depended on context. We found that high process and measurement error reduced the reliability of both models in predicted percent decline. Both sources of error contributed strongly to biased predictions, with process error tending to contribute to the spread of predictions more than measurement error. Increasing time series length improved precision and reduced bias of predicted population trends, but gains substantially diminished for time series lengths greater than 10-15 years. The simple parameterization scheme we employed contributed strongly to bias in matrix model predictions when both process and measurement error were high, causing scalar models to exhibit similar or greater precision and lower bias than matrix models. Our study provides evidence that, for short-lived species with structured but simple life histories, short time series and simple models can be sufficient for reasonably reliable conservation

  8. Combined Influences of Model Choice, Data Quality, and Data Quantity When Estimating Population Trends

    PubMed Central

    Rueda-Cediel, Pamela; Anderson, Kurt E.; Regan, Tracey J.; Franklin, Janet; Regan, Helen M.

    2015-01-01

    Estimating and projecting population trends using population viability analysis (PVA) are central to identifying species at risk of extinction and for informing conservation management strategies. Models for PVA generally fall within two categories, scalar (count-based) or matrix (demographic). Model structure, process error, measurement error, and time series length all have known impacts in population risk assessments, but their combined impact has not been thoroughly investigated. We tested the ability of scalar and matrix PVA models to predict percent decline over a ten-year interval, selected to coincide with the IUCN Red List criterion A.3, using data simulated for a hypothetical, short-lived organism with a simple life-history and for a threatened snail, Tasmaphena lamproides. PVA performance was assessed across different time series lengths, population growth rates, and levels of process and measurement error. We found that the magnitude of effects of measurement error, process error, and time series length, and interactions between these, depended on context. We found that high process and measurement error reduced the reliability of both models in predicted percent decline. Both sources of error contributed strongly to biased predictions, with process error tending to contribute to the spread of predictions more than measurement error. Increasing time series length improved precision and reduced bias of predicted population trends, but gains substantially diminished for time series lengths greater than 10–15 years. The simple parameterization scheme we employed contributed strongly to bias in matrix model predictions when both process and measurement error were high, causing scalar models to exhibit similar or greater precision and lower bias than matrix models. Our study provides evidence that, for short-lived species with structured but simple life histories, short time series and simple models can be sufficient for reasonably reliable conservation

  9. US Hemophilia Treatment Center population trends 1990-2010: patient diagnoses, demographics, health services utilization.

    PubMed

    Baker, J R; Riske, B; Drake, J H; Forsberg, A D; Atwood, R; Voutsis, M; Shearer, R

    2013-01-01

    For several decades, US government agencies have partially supported regional networks of Hemophilia Treatment Centers (HTC). HTC multidisciplinary teams provide comprehensive and coordinated diagnosis, treatment, prevention, education, outreach and surveillance services to improve the health of people with genetic bleeding disorders. However, national data are scarce on HTC-patient population trends and services. The aim of the study was to examine national trends over the past 20 years in patient diagnoses, demographics and health services utilization among the Health Resources and Services Administration (HRSA) and Centers for Disease Control and Prevention (CDC)-supported HTC network. Diagnoses, demographics and health services utilization data from 1990 to 2010 were aggregated from all HTCs using the Hemophilia Data Set (HDS). From 1990 to 2010, the HTC population grew 90% from 17 177 to 32 612. HTC patients with von Willebrand's disease increased by 148%, females by 346%, Hispanic patients by 236% and African Americans by 104%. Four thousand and seventy-five deaths were reported. From 2002 to 2010, annual comprehensive evaluations grew 38%, and persons with severe haemophilia on a home intravenous therapy programme rose 37%. In 2010, 46% of patients were less than 18 years vs. 24% for the general US population. The Hemophilia Data Set documents the growth and diversity of the US Hemophilia Treatment Center Network's patient population and services. Despite disproportionate deaths due to HIV, the HTC patient base grew faster than the general US population. The HDS is a vital national public health registry for this rare-disorder population. PMID:22845803

  10. On the decline of the Rusty Blackbird and the use of ornithological literature to document long-term population trends

    USGS Publications Warehouse

    Greenberg, R.; Droege, S.

    1999-01-01

    Unlike most North American blackbirds, Rusty Blackbirds (Euphagus carolensis) have shown steep population declines. Declines of approximately 90% are indicated for three recent decades from the Breeding Bird Survey, Christmas Bird Counts, and Quebec Checklist Program. Analyses of abundance classifications in bird distribution books and annotated checklists reveal an overlooked but long-term decline dating back to at least the early part of this century. Rusty Blackbirds were described as very common to abundant in 5656 of the pre-192O published accounts, 19% of the 1921-1950 accounts, and only 7% of the post-1950 accounts. Rusty Blackbirds were described as uncommon in none of the pre-1950 accounts, 18% of the 1951-1980 accounts, and 43% of the post-1980 accounts. A similar pattern was found for analyses based on local checklists. Destruction of wooded wetlands on wintering grounds, acid precipitation, and the conversion of boreal forest wetlands could have contributed to these declines. Systematic analysis of regional guides and checklists provides a valuable tool for examining large-scale and long-term population changes in birds.

  11. Trends in the use of pulmonary artery catheterization in the aneurysmal subarachnoid hemorrhage population.

    PubMed

    Inouye, S; Jin, D; Cen, S; Nguyen, P; Renda, N; Amar, A P; Mack, W J; Kim-Tenser, M A

    2016-09-01

    Use of the pulmonary artery catheter (PAC) has been controversial since the late 1980s. Multi-center observational and randomized controlled trials (RCTs) have concluded that PACs fail to decrease mortality. Subsequently, studies have looked for a decline in PAC use that corresponds to the literature and have indeed found that it exists. However, none to date have looked primarily at trends in the aneurysmal subarachnoid hemorrhage (aSAH) population. This study uses the Nationwide Inpatient Sample (NIS) from 2000-2010 to identify trends in PAC use among patients with aSAH. Trend analysis was assessed using a multivariable regression model with a calculation of slope of PAC frequency over time for pre-2005 and post-2005. Trends in mortality and routine discharge were also assessed for the same time period. 363,096 SAH patients were extrapolated using survey weights, of whom 6,988 had a PAC. Over time, PAC use declined, with a significant downward shift in the year 2005. Analyses also showed a decrease in mortality over the same time period. Our results show that PAC use among patients with aSAH decreased from 2000 to 2010. Similar to other studies, the decline appears to be temporally related to RCTs that showed a lack of benefit from PAC. Studies such as these have the potential to influence clinical practice through illumination of shifting opinions and approaches. PMID:27068011

  12. Advanced long-term bird banding and climate data mining in spring confirm passerine population declines for the Northeast Chinese-Russian flyway

    NASA Astrophysics Data System (ADS)

    Jiao, Shengwu; Huettmann, Falk; Guo, Yumin; Li, Xianda; Ouyang, Yanlan

    2016-09-01

    The migration of birds is fascinating for humans but it's also a serious environmental monitoring and management issue on a global level. Bird banding using mistnets has been the method of choice for decades worldwide; linking these data with climate data allows to infer on global warming and outlier events. However, good methods to achieve this effectively in time and space for many species are still missing; data for Asia are specifically sparse and often 'messy'. Here we present a data mining summary information for data from two bird banding stations (Gaofeng and Qingfeng) along the vast Northeast Chinese-Russian flyway. Bird data were collected during spring 2002-2011 with standardized techniques and then linked with related climate data in the banding as well as the wintering sites. This creates a complex data set which is based on a decade and which includes many predictors. This first-time data mining analysis with 'data cloning' and machine learning methods (boosted regression trees) shows how to extract the major signals in this unique dataset from highly correlated and interacting predictors. Our results indicate a large-scale warming trend for the flyway, with a start in 2003, and a freezing rain outlier event in 2008; the last years remained on a rather warm level. All evidence along this vast flyway supports major changes, warming trends, habitat losses and consequently strong passerine declines. Presumably human pressures are a major factor either way and we propose to address these problems immediately for betterment if meaningful conservation targets are to be met.

  13. Site-occupancy distribution modeling to correct population-trend estimates derived from opportunistic observations.

    PubMed

    Kéry, Marc; Royle, J Andrew; Schmid, Hans; Schaub, Michael; Volet, Bernard; Häfliger, Guido; Zbinden, Niklaus

    2010-10-01

    Species' assessments must frequently be derived from opportunistic observations made by volunteers (i.e., citizen scientists). Interpretation of the resulting data to estimate population trends is plagued with problems, including teasing apart genuine population trends from variations in observation effort. We devised a way to correct for annual variation in effort when estimating trends in occupancy (species distribution) from faunal or floral databases of opportunistic observations. First, for all surveyed sites, detection histories (i.e., strings of detection-nondetection records) are generated. Within-season replicate surveys provide information on the detectability of an occupied site. Detectability directly represents observation effort; hence, estimating detectability means correcting for observation effort. Second, site-occupancy models are applied directly to the detection-history data set (i.e., without aggregation by site and year) to estimate detectability and species distribution (occupancy, i.e., the true proportion of sites where a species occurs). Site-occupancy models also provide unbiased estimators of components of distributional change (i.e., colonization and extinction rates). We illustrate our method with data from a large citizen-science project in Switzerland in which field ornithologists record opportunistic observations. We analyzed data collected on four species: the widespread Kingfisher (Alcedo atthis) and Sparrowhawk (Accipiter nisus) and the scarce Rock Thrush (Monticola saxatilis) and Wallcreeper (Tichodroma muraria). Our method requires that all observed species are recorded. Detectability was <1 and varied over the years. Simulations suggested some robustness, but we advocate recording complete species lists (checklists), rather than recording individual records of single species. The representation of observation effort with its effect on detectability provides a solution to the problem of differences in effort encountered when

  14. Population Trends of Small-Scale Spanwise Vortices in Wall Turbulence

    NASA Astrophysics Data System (ADS)

    Wu, Y.

    2005-11-01

    The population trends of prograde and retrograde (counter to the sense of the mean shear) spanwise vortex cores are studied via detailed PIV measurements in the streamwise--wall-normal plane of turbulent channel flow at Reτ=566, 1184 and 1759 and in a zero-pressure-gradient turbulent boundary layer at &+circ;=1401 and 2347. A vortex extraction algorithm is used to isolate individual small-scale spanwise vortex cores from the background turbulence and the population trends of these vortices are studied as a function of Reynolds number and wall-normal position in both flows. Substantial numbers of prograde spanwise vortices with structural signatures consistent with the heads of hairpin-like vortices are found to populate the inner boundary of the log layer. In addition, a significant number of retrograde vortices also exist, sometimes appearing as isolated structures but often forming counter-rotating vortex pairs with the remaining prograde vortices. Retrograde vortices are found to be most prominent near the outer edge of the log layer of both turbulent channel flow and the turbulent boundary layer, indicating that they may be generated locally within the log layer, advected into this region from more-distant wall-normal locations, and/or may be the byproduct of vortex merging. Of particular significance is the observation that the fractions of prograde and retrograde spanwise vortices collapse irrespective of Reynolds-number and flow in the log layer of wall turbulence.

  15. Secular trends in body height in Balkan populations from 1945 to 1995

    PubMed Central

    Sarajlić, Nermin; Resić, Emina; Gradaščević, Anisa; Salihbegović, Adis; Balažic, Jože; Zupanc, and Tomaž

    2014-01-01

    The aim of this study was to look for any secular trend in the stature of Balkan populations from the time of World War II (1939–1945) to the Balkans War (1991–1995). The research was based on the examination of exhumed skeletons of 202 men killed in World War II in the area of the Republic of Slovenia, and 243 men killed in the Bosnian War in Bosnia and Herzegovina. The length measurements of the right and left humerus, femur, tibia and fibula were taken. Since the results revealed no significant differences and the left-sided bones were more complete and recurrent in the sample, the bones of the left side were used in the analysis. Since the increase in height depends mostly on the increase in length of the long bones, with an average absolute change of about 0.28 cm for humerus, 0.55 cm for femur, 0.49 cm for tibia and 0.20 cm for fibula per decade in our case, these results suggest a significant increase of the height of the Balkans population. The difference of the sum of the average femur and tibia length for the study period was 4.13 cm. Recalculated average length increase of the sum length of femur and tibia per decade was 0.88 cm for the left side. Our study revealed that there was a trend towards increased long bone lengths, at least in the male population analyzed. PMID:25428672

  16. Population genetic structure and direct observations reveal sex-reversed patterns of dispersal in a cooperative bird

    PubMed Central

    Harrison, Xavier A; York, Jennifer E; Young, Andrew J

    2014-01-01

    Sex-biased dispersal is pervasive and has diverse evolutionary implications, but the fundamental drivers of dispersal sex biases remain unresolved. This is due in part to limited diversity within taxonomic groups in the direction of dispersal sex biases, which leaves hypothesis testing critically dependent upon identifying rare reversals of taxonomic norms. Here, we use a combination of observational and genetic data to demonstrate a rare reversal of the avian sex bias in dispersal in the cooperatively breeding white-browed sparrow weaver (Plocepasser mahali). Direct observations revealed that (i) natal philopatry was rare, with both sexes typically dispersing locally to breed, and (ii), unusually for birds, males bred at significantly greater distances from their natal group than females. Population genetic analyses confirmed these patterns, as (i) corrected Assignment index (AIc), FST tests and isolation-by-distance metrics were all indicative of longer dispersal distances among males than females, and (ii) spatial autocorrelation analysis indicated stronger within-group genetic structure among females than males. Examining the spatial scale of extra-group mating highlighted that the resulting ‘sperm dispersal’ could have acted in concert with individual dispersal to generate these genetic patterns, but gamete dispersal alone cannot account entirely for the sex differences in genetic structure observed. That leading hypotheses for the evolution of dispersal sex biases cannot readily account for these sex-reversed patterns of dispersal in white-browed sparrow weavers highlights the continued need for attention to alternative explanations for this enigmatic phenomenon. We highlight the potential importance of sex differences in the distances over which dispersal opportunities can be detected. PMID:25346189

  17. Latino Population Growth, Characteristics, and Settlement Trends: Implications for Social Work Education in a Dynamic Political Climate

    ERIC Educational Resources Information Center

    Vidal de Haymes, Maria; Kilty, Keith M.

    2007-01-01

    This paper identifies a number of significant contemporary trends in the Latino population, including the striking growth of the community, new points of entry and settlement for recent immigrants, the mixed-status nature of families, and the increase in the proportion of U.S. households that speak Spanish. The implications of these trends for…

  18. Habitat availability is a more plausible explanation than insecticide acute toxicity for U.S. grassland bird species declines.

    PubMed

    Hill, Jason M; Egan, J Franklin; Stauffer, Glenn E; Diefenbach, Duane R

    2014-01-01

    Grassland bird species have experienced substantial declines in North America. These declines have been largely attributed to habitat loss and degradation, especially from agricultural practices and intensification (the habitat-availability hypothesis). A recent analysis of North American Breeding Bird Survey (BBS) "grassland breeding" bird trends reported the surprising conclusion that insecticide acute toxicity was a better correlate of grassland bird declines in North America from 1980-2003 (the insecticide-acute-toxicity hypothesis) than was habitat loss through agricultural intensification. In this paper we reached the opposite conclusion. We used an alternative statistical approach with additional habitat covariates to analyze the same grassland bird trends over the same time frame. Grassland bird trends were positively associated with increases in area of Conservation Reserve Program (CRP) lands and cropland used as pasture, whereas the effect of insecticide acute toxicity on bird trends was uncertain. Our models suggested that acute insecticide risk potentially has a detrimental effect on grassland bird trends, but models representing the habitat-availability hypothesis were 1.3-21.0 times better supported than models representing the insecticide-acute-toxicity hypothesis. Based on point estimates of effect sizes, CRP area and agricultural intensification had approximately 3.6 and 1.6 times more effect on grassland bird trends than lethal insecticide risk, respectively. Our findings suggest that preserving remaining grasslands is crucial to conserving grassland bird populations. The amount of grassland that has been lost in North America since 1980 is well documented, continuing, and staggering whereas insecticide use greatly declined prior to the 1990s. Grassland birds will likely benefit from the de-intensification of agricultural practices and the interspersion of pastures, Conservation Reserve Program lands, rangelands and other grassland habitats into

  19. Differing trends in the incidence of vascular comorbidity in MS and the general population

    PubMed Central

    Fisk, John; Tremlett, Helen; Wolfson, Christina; Warren, Sharon; Blanchard, James; Patten, Scott B.

    2016-01-01

    Abstract Background: Although the adverse effects of vascular comorbidities are increasingly recognized in multiple sclerosis (MS), the epidemiology of these conditions remains poorly understood. Methods: Using population-based administrative data, we identified 44,452 Canadians with MS and 220,849 age-, sex- and geographically matched controls. We applied validated definitions to estimate the incidence of diabetes, hypertension, hyperlipidemia, and ischemic heart disease (IHD) from 1995 to 2005. Results: Of the MS cases, 31,757 (71.4%) were in female participants, with a mean (SD) age at the index date of 43.8 (13.7) years. Over time, the age-standardized incidence of diabetes rose more in the MS population (incidence rate ratio [IRR] per year 1.06; 95% confidence interval [CI] 1.03–1.08) than in the matched population (IRR per year 1.02; 95% CI 1.01–1.03). Temporal trends in the age-standardized incidence of hyperlipidemia, hypertension, and IHD were similar in both populations. Among those aged 20–44 years, the incidence of IHD was higher in the MS population (IRR 1.59; 95% CI 1.19–2.11). The increased incidence of IHD in the MS population was attenuated among those aged 60 years and older (IRR 1.01; 95% CI 0.97–1.06). Conclusions: The incidence rates of diabetes, hypertension, and hyperlipidemia are rising within the MS population. Programs to systematically prevent and treat these conditions are needed. PMID:27104065

  20. A brief report on the illegal cage-bird trade in southern Florida: a potentially serious negative impact on the eastern population of Painted Bunting (Passerina ciris)

    USGS Publications Warehouse

    Sykes, P.W., Jr.; Manfredi, L.; Padura, M.

    2006-01-01

    Populations of Painted Bunting (Passerina ciris) have been declining annually over the past 35 years. A cursory survey indicates that illegal trapping of Painted Buntings for a black market cage-bird trade is widespread in southeastern Florida. Coupled with other negative factors confronting the eastern population, the trapping of buntings for the cagebird trade may, in time, produce dire results for this native songbird. Law enforcement personnel need to continue to monitor the illegal activity of trapping native passerines for the local songbird market and to continue to arrest those who support it.

  1. Trends in Notifiable Infectious Diseases in China: Implications for Surveillance and Population Health Policy

    PubMed Central

    Zhang, Lei; Wilson, David P.

    2012-01-01

    This study aimed to analyse trends in notifiable infectious diseases in China, in their historical context. Both English and Chinese literature was searched and diseases were categorised according to the type of disease or transmission route. Temporal trends of morbidity and mortality rates were calculated for eight major infectious diseases types. Strong government commitment to public health responses and improvements in quality of life has led to the eradication or containment of a wide range of infectious diseases in China. The overall infectious diseases burden experienced a dramatic drop during 1975–1995, but since then, it reverted and maintained a gradual upward trend to date. Most notifiable diseases are contained at a low endemic level; however, local small-scale outbreaks remain common. Tuberculosis, as a bacterial infection, has re-emerged since the 1990s and has become prevalent in the country. Sexually transmitted infections are in a rapid, exponential growth phase, spreading from core groups to the general population. Together human immunodeficiency virus (HIV), they account for 39% of all death cases due to infectious diseases in China in 2008. Zoonotic infections, such as severe acute respiratory syndrome (SARS), rabies and influenza, pose constant threats to Chinese residents and remain the most deadly disease type among the infected individuals. Therefore, second-generation surveillance of behavioural risks or vectors associated with pathogen transmission should be scaled up. It is necessary to implement public health interventions that target HIV and relevant coinfections, address transmission associated with highly mobile populations, and reduce the risk of cross-species transmission of zoonotic pathogens. PMID:22359565

  2. Mountain goat abundance and population trends in the Olympic Mountains, Washington, 2011

    USGS Publications Warehouse

    Jenkins, Kurt; Happe, Patricia; Griffin, Paul C.; Beirne, Katherine; Hoffman, Roger; Baccus, William

    2011-01-01

    We conducted an aerial helicopter survey between July 18 and July 25, 2011, to estimate abundance and trends of introduced mountain goats (Oreamnos americanus) in the Olympic Mountains. The survey was the first since we developed a sightability correction model in 2008, which provided the means to estimate the number of mountain goats present in the surveyed areas and not seen during the aerial surveys, and to adjust for undercounting biases. Additionally, the count was the first since recent telemetry studies revealed that the previously defined survey zone, which was delineated at lower elevations by the 1,520-meter elevation contour, did not encompass all lands used by mountain goats during summer. We redefined the lower elevation boundary of survey units before conducting the 2011 surveys in an effort to more accurately estimate the entire mountain goat population. We surveyed 39 survey units, comprising 39 percent of the 59,615-hectare survey area. We estimated a mountain goat population of 344±44 (standard error, SE) in the expanded survey area. Based on this level of estimation uncertainty, the 95-percent confidence interval ranged from 258 to 430 mountain goats at the time of the survey. To permit comparisons of mountain goat populations between the 2004 and 2011 surveys, we recomputed population estimates derived from the 2004 survey using the newly developed bias correction methods, and we computed the 2004 and 2011 surveys based on comparable survey zone definitions (for example, using the boundaries of the 2004 survey). The recomputed estimates of mountain goat populations were 217±19 (SE) in 2004 and 303±41(SE) in 2011. The difference between the current 2011 population estimate (344±44[SE]) and the recomputed 2011 estimate (303±41[SE]) reflects the number of mountain goats counted in the expanded lower elevation portions of the survey zone added in 2011. We conclude that the population of mountain goats has increased in the Olympic Mountains at

  3. Long term trends in prevalence of neural tube defects in Europe: population based study

    PubMed Central

    Loane, Maria; de Walle, Hermien; Arriola, Larraitz; Addor, Marie-Claude; Barisic, Ingeborg; Beres, Judit; Bianchi, Fabrizio; Dias, Carlos; Draper, Elizabeth; Garne, Ester; Gatt, Miriam; Haeusler, Martin; Klungsoyr, Kari; Latos-Bielenska, Anna; Lynch, Catherine; McDonnell, Bob; Nelen, Vera; Neville, Amanda J; O’Mahony, Mary T; Queisser-Luft, Annette; Rankin, Judith; Rissmann, Anke; Ritvanen, Annukka; Rounding, Catherine; Sipek, Antonin; Tucker, David; Verellen-Dumoulin, Christine; Wellesley, Diana; Dolk, Helen

    2015-01-01

    Study question What are the long term trends in the total (live births, fetal deaths, and terminations of pregnancy for fetal anomaly) and live birth prevalence of neural tube defects (NTD) in Europe, where many countries have issued recommendations for folic acid supplementation but a policy for mandatory folic acid fortification of food does not exist? Methods This was a population based, observational study using data on 11 353 cases of NTD not associated with chromosomal anomalies, including 4162 cases of anencephaly and 5776 cases of spina bifida from 28 EUROCAT (European Surveillance of Congenital Anomalies) registries covering approximately 12.5 million births in 19 countries between 1991 and 2011. The main outcome measures were total and live birth prevalence of NTD, as well as anencephaly and spina bifida, with time trends analysed using random effects Poisson regression models to account for heterogeneities across registries and splines to model non-linear time trends. Summary answer and limitations Overall, the pooled total prevalence of NTD during the study period was 9.1 per 10 000 births. Prevalence of NTD fluctuated slightly but without an obvious downward trend, with the final estimate of the pooled total prevalence of NTD in 2011 similar to that in 1991. Estimates from Poisson models that took registry heterogeneities into account showed an annual increase of 4% (prevalence ratio 1.04, 95% confidence interval 1.01 to 1.07) in 1995-99 and a decrease of 3% per year in 1999-2003 (0.97, 0.95 to 0.99), with stable rates thereafter. The trend patterns for anencephaly and spina bifida were similar, but neither anomaly decreased substantially over time. The live birth prevalence of NTD generally decreased, especially for anencephaly. Registration problems or other data artefacts cannot be excluded as a partial explanation of the observed trends (or lack thereof) in the prevalence of NTD. What this study adds In the absence of mandatory fortification

  4. Effect of Energy Under-Reporting on Secular Trends of Dietary Patterns in a Mediterranean Population

    PubMed Central

    Funtikova, Anna N.; Gomez, Santiago F.; Fitó, Montserrat; Elosua, Roberto; Benítez-Arciniega, Alejandra A.; Schröder, Helmut

    2015-01-01

    Background Diet is an important factor in the prevention of chronic diseases. Analysis of secular trends of dietary patterns can be biased by energy under-reporting. Therefore, the objective of the present study was to analyse the impact of energy under-reporting on dietary patterns and secular trends in dietary patterns defined by cluster analysis. Design and methods Two cross-sectional population-based surveys were conducted in Spain, in 2000 and 2005, with 3058 and 6352 participants, respectively, aged 25 to 74 years. Validated questionnaire was used to collect dietary data. Cluster analysis was run separately for all participants, plausible energy reporters (PER), and energy under-reporters (EUR) to define dietary patterns. Results Three clusters, “healthy”, “mixed” and “western”, were identified for both surveys. The “mixed” cluster was the predominant cluster in both surveys. Excluding EUR reduced the proportion of the “mixed” cluster up to 6.40% in the 2000 survey; this caused secular trend increase in the prevalence of the “mixed” pattern. Cross-classification analysis of all participants and PER’ data showed substantial agreement in cluster assignments: 68.7% in 2000 and 84.4% in 2005. Excluding EUR did not cause meaningful (≥15%) changes in the “healthy” pattern. It provoked changes in consumption of some food groups in the “mixed” and “western” patterns: mainly decreases of unhealthy foods within the 2000 and increases of unhealthy foods within the 2005 surveys. Secular trend effects of EUR were similar to those within the 2005 survey. Excluding EUR reversed the direction of secular trends in consumption of several food groups in PER in the “mixed” and “western” patterns. Conclusions EUR affected distribution of participants between dietary patterns within and between surveys, secular trends in food group consumption and amount of food consumed in all, but not in the “healthy” pattern. Our findings

  5. Do HIV Prevalence Trends in ANC Surveillance Represent Trends in the General Population in the ART Era? The Case of Manicaland, East Zimbabwe

    PubMed Central

    Gregson, Simon; Dharmayat, Kanika; Pereboom, Monique; Takaruza, Albert; Mugurungi, Owen; Schur, Nadine; Nyamukapa, Constance A.

    2016-01-01

    Objective National estimates of HIV trends in generalised epidemics rely on HIV prevalence data from antenatal clinic (ANC) surveillance. We investigate whether HIV prevalence trends in ANC data reflect trends in men and women in the general population during the scale-up of anti-retroviral treatment (ART) in Manicaland, Zimbabwe. Methods Trends in HIV prevalence in local ANC attendees and adults aged 15-49yrs in towns, agricultural estates, and villages were compared using five rounds of parallel ANC (N≈1,200) and general-population surveys (N≈10,000) and multi-variable log-linear regression. Changes in the age-pattern of HIV prevalence and the age-distribution of ANC attendees were compared with those in the general population. Age-specific pregnancy prevalence rates were compared by HIV infection and ART status. Results Cumulatively, from 1998-2000 to 2009-2011, HIV prevalence fell by 60.0% (95% CI, 51.1%-67.3%) in ANC surveillance data and by 34.3% (30.8%-37.7%) in the general population. Most of the difference arose following the introduction of ART (2006-2011). The estates and villages reflected this overall pattern but HIV prevalence in the towns was lower at local ANCs than in the general population, largely due to attendance by pregnant women from outlying (lower prevalence) areas. The ageing of people living with HIV in the general population (52.4% aged >35yrs, 2009-2011) was under-represented in the ANC data (12.6%) due to lower fertility in older and HIV-infected women. Conclusion After the introduction of ART in Manicaland, HIV prevalence declined more steeply in ANC surveillance data than in the general population. Models used for HIV estimates must reflect this change in bias. PMID:26372390

  6. Assessing the status and trend of bat populations across broad geographic regions with dynamic distribution models.

    PubMed

    Rodhouse, Thomas J; Ormsbee, Patricia C; Irvine, Kathryn M; Vierling, Lee A; Szewczak, Joseph M; Vierling, Kerri T

    2012-06-01

    Bats face unprecedented threats from habitat loss, climate change, disease, and wind power development, and populations of many species are in decline. A better ability to quantify bat population status and trend is urgently needed in order to develop effective conservation strategies. We used a Bayesian autoregressive approach to develop dynamic distribution models for Myotis lucifugus, the little brown bat, across a large portion of northwestern USA, using a four-year detection history matrix obtained from a regional monitoring program. This widespread and abundant species has experienced precipitous local population declines in northeastern USA resulting from the novel disease white-nose syndrome, and is facing likely range-wide declines. Our models were temporally dynamic and accounted for imperfect detection. Drawing on species-energy theory, we included measures of net primary productivity (NPP) and forest cover in models, predicting that M. lucifugus occurrence probabilities would covary positively along those gradients. Despite its common status, M. lucifugus was only detected during -50% of the surveys in occupied sample units. The overall naive estimate for the proportion of the study region occupied by the species was 0.69, but after accounting for imperfect detection, this increased to -0.90. Our models provide evidence of an association between NPP and forest cover and M. lucifugus distribution, with implications for the projected effects of accelerated climate change in the region, which include net aridification as snowpack and stream flows decline. Annual turnover, the probability that an occupied sample unit was a newly occupied one, was estimated to be low (-0.04-0.14), resulting in flat trend estimated with relatively high precision (SD = 0.04). We mapped the variation in predicted occurrence probabilities and corresponding prediction uncertainty along the productivity gradient. Our results provide a much needed baseline against which future

  7. North American Breeding Bird Survey Annual Summary, 1988

    USGS Publications Warehouse

    Droege, S.; Sauer, J.R.

    1989-01-01

    Introduction: The North American Breeding Bird Survey (BBS) is run by approximately 2,000 skilled amateur ornithologists, and is coordinated cooperatively by the U.S. Fish and Wildlife Service and the Canadian Wildlife Service. Beginning in 1966, BBS cooperators have been collecting standardized information on North American bird populations. The BBS is a roadside survey, comprised of permanent routes that are surveyed yearly. Each route is 39.4 km (24.5 miles) long and consists of 50 stops spaced 0.8 km (0.5 mile) apart. All birds heard or seen during a 3-min observation period at each stop are recorded, and the sum of the individual stops for each species is used as an index of species density on the route. In this report, we present the population changes of the 222 bird species reported on > 50 BBS routes during 1987 and 1988. Population trends for 1966-87 are presented for comparison. Owing to space constraints, trends are not reported for States, Provinces, or physiographic regions. Instead, we present maps illustrating patterns of population change for selected species, and summarize State and physiographic strata patterns of population change as the proportion of species that increased in each region. Detailed State, Provincial, and physiographic strata changes arc available to interested readers.

  8. Understanding the contribution of habitats and regional variation to long-term population trends in tricolored blackbirds

    PubMed Central

    Graves, Emily E; Holyoak, Marcel; Rodd Kelsey, T; Meese, Robert J

    2013-01-01

    Population trends represent a minimum amount of information required to assess the conservation status of a species. However, understanding and detecting trends can be complicated by variation among habitats and regions, and by dispersal connecting habitats through source-sink dynamics. We analyzed trends in breeding populations between habitats and regions to better understand the overall dynamics of a species' decline. Specifically, we analyzed historical trends in breeding populations of tricolored blackbirds (Agelaius tricolor) using breeding records from 1907 to 2009. The species breeds itinerantly and ephemerally uses multiple habitat types and breeding areas, which make interpretation of trends complex. We found overall abundance declines of 63% between 1935 and 1975. Since 1980 overall declines became nonsignificant and obscure despite large amounts of data from 1980 to 2009. Temporal trends differed between breeding habitat types and were associated with regional differences in population declines. A new habitat, triticale crops (a wheat-rye hybrid grain) produced colonies 40× larger, on average, than other breeding habitats, and contributed to a change in regional distribution since it primarily occurred in a single region. The mechanism for such an effect is not clear, but could represent the local availability of foodstuffs in the landscape rather than something specific to triticale crops. While variation in trends among habitats clearly occurred, they could not easily be ascribed to source-sink dynamics, ecological traps, habitat selection or other detailed ecological mechanisms. Nonetheless, such exchanges provide valuable information to guide management of dynamic systems. PMID:24101977

  9. Understanding the contribution of habitats and regional variation to long-term population trends in tricolored blackbirds.

    PubMed

    Graves, Emily E; Holyoak, Marcel; Rodd Kelsey, T; Meese, Robert J

    2013-09-01

    Population trends represent a minimum amount of information required to assess the conservation status of a species. However, understanding and detecting trends can be complicated by variation among habitats and regions, and by dispersal connecting habitats through source-sink dynamics. We analyzed trends in breeding populations between habitats and regions to better understand the overall dynamics of a species' decline. Specifically, we analyzed historical trends in breeding populations of tricolored blackbirds (Agelaius tricolor) using breeding records from 1907 to 2009. The species breeds itinerantly and ephemerally uses multiple habitat types and breeding areas, which make interpretation of trends complex. We found overall abundance declines of 63% between 1935 and 1975. Since 1980 overall declines became nonsignificant and obscure despite large amounts of data from 1980 to 2009. Temporal trends differed between breeding habitat types and were associated with regional differences in population declines. A new habitat, triticale crops (a wheat-rye hybrid grain) produced colonies 40× larger, on average, than other breeding habitats, and contributed to a change in regional distribution since it primarily occurred in a single region. The mechanism for such an effect is not clear, but could represent the local availability of foodstuffs in the landscape rather than something specific to triticale crops. While variation in trends among habitats clearly occurred, they could not easily be ascribed to source-sink dynamics, ecological traps, habitat selection or other detailed ecological mechanisms. Nonetheless, such exchanges provide valuable information to guide management of dynamic systems. PMID:24101977

  10. Trends in suicidal behaviour and use of mental health services in Canadian military and civilian populations

    PubMed Central

    Sareen, Jitender; Afifi, Tracie O.; Taillieu, Tamara; Cheung, Kristene; Turner, Sarah; Bolton, Shay-Lee; Erickson, Julie; Stein, Murray B.; Fikretoglu, Deniz; Zamorski, Mark A.

    2016-01-01

    Background: In the context of the Canadian mission in Afghanistan, substantial media attention has been placed on mental health and lack of access to treatment among Canadian Forces personnel. We compared trends in the prevalence of suicidal behaviour and the use of mental health services between Canadian military personnel and the general population from 2002 to 2012/13. Methods: We obtained data for respondents aged 18–60 years who participated in 4 nationally representative surveys by Statistics Canada designed to permit comparisons between populations and trends over time. Surveys of the general population were conducted in 2002 (n = 25 643) and 2012 (n = 15 981); those of military personnel were conducted in 2002 (n = 5153) and 2013 (n = 6700). We assessed the lifetime and past-year prevalence of suicidal ideation, plans and attempts, as well as use of mental health services. Results: In 2012/13, but not in 2002, military personnel had significantly higher odds of both lifetime and past-year suicidal ideation than the civilian population (lifetime: adjusted odds ratio [OR] 1.32, 95% confidence interval [CI] 1.17–1.50; past year: adjusted OR 1.34, 95% CI 1.09–1.66). The same was true for suicidal plans (lifetime: adjusted OR 1.64, 95% CI 1.35–1.99; past year: adjusted OR 1.66, 95% CI 1.18–2.33). Among respondents who reported past-year suicidal ideation, those in the military had a significantly higher past-year utilization rate of mental health services than those in the civilian population in both 2002 (adjusted OR 2.02, 95% CI 1.31–3.13) and 2012/13 (adjusted OR 3.14, 95% CI 1.86–5.28). Interpretation: Canadian Forces personnel had a higher prevalence of suicidal ideation and plans in 2012/13 and a higher use of mental health services in 2002 and 2012/13 than the civilian population. PMID:27221270

  11. Trends in stimulant use in Australia: A comparison of wastewater analysis and population surveys.

    PubMed

    Tscharke, Benjamin J; Chen, Chang; Gerber, Jacobus P; White, Jason M

    2015-12-01

    Levels of community drug use are usually described by national surveys; data relied upon by decision makers in health and law enforcement. In recent years the analysis of wastewater for drugs and their metabolites has become prominent. Both methods convey unique drug use information. This paper demonstrates differences arising from the two approaches, using methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA) and cocaine data from the state of South Australia. The proportion of people using each drug, obtained from three prominent drug surveys, was compared with estimates of total community drug use derived by wastewater analysis. Temporal trends were compared for available years of the surveys and wastewater analysis from 2010 to 2013. Wastewater results showed methamphetamine to be the most prevalent stimulant in Adelaide, South Australia, with an average of 24.4±1.7 doses per day per 1000 inhabitants for 2013, while consumption of MDMA and cocaine were much lower at 0.52±0.12 and 0.42±0.06 doses per day per 1000 inhabitants, respectively. Survey data typically had MDMA as the most used stimulant on a proportion of the population basis. The difference in magnitude of drug use between MDMA and methamphetamine was also less apparent. Temporal trends of the proportion of the population using a drug by surveys did not generally reflect total use within the community which was observed by wastewater analysis. Survey data are excellent for describing users demographically. However, discrepancies between the proportion of the population who are users and the magnitude of drug use can lead to misrepresentation of the overall scale of use. The results from this study indicate methamphetamine was used to a much greater extent than suggested by the surveys. Together, wastewater analysis and survey data give a comprehensive view of the drug problem enabling more informed decisions on drug policy. PMID:26225740

  12. Long Term Population, City Size and Climate Trends in the Fertile Crescent: A First Approximation.

    PubMed

    Lawrence, Dan; Philip, Graham; Hunt, Hannah; Snape-Kennedy, Lisa; Wilkinson, T J

    2016-01-01

    Over the last 8000 years the Fertile Crescent of the Near East has seen the emergence of urban agglomerations, small scale polities and large territorial empires, all of which had profound effects on settlement patterns. Computational approaches, including the use of remote sensing data, allow us to analyse these changes at unprecedented geographical and temporal scales. Here we employ these techniques to examine and compare long term trends in urbanisation, population and climate records. Maximum city size is used as a proxy for the intensity of urbanisation, whilst population trends are modelled from settlement densities in nine archaeological surveys conducted over the last 30 years across the region. These two measures are then compared with atmospheric moisture levels derived from multiple proxy analyses from two locations close to the study area, Soreq Cave in Israel and Lake Van in south-eastern Turkey, as well as wider literature. The earliest urban sites emerged during a period of relatively high atmospheric moisture levels and conform to a series of size thresholds. However, after the Early Bronze Age maximum urban size and population levels increase rapidly whilst atmospheric moisture declines. We argue that although the initial phase of urbanization may have been linked to climate conditions, we can see a definitive decoupling of climate and settlement patterns after 2000 BC. We relate this phenomenon to changes in socio-economic organisation and integration in large territorial empires. The complex relationships sustaining urban growth during this later period resulted in an increase in system fragility and ultimately impacted on the sustainability of cities in the long term. PMID:27018998

  13. Temporal trends in vascular trauma in Ontario, 1991-2009: a population-based study

    PubMed Central

    Altoijry, Abdulmajeed; Al-Omran, Mohammed; Johnston, K. Wayne; Mamdani, Muhammad; Lindsay, Thomas F.

    2016-01-01

    Background: Vascular injuries add substantial complexity to trauma care, yet Canadian epidemiologic data on such injuries are not readily available. We conducted a retrospective cross-sectional study to examine temporal trends in the rate of hospital admissions for vascular injuries from 1991 to 2009 in Ontario. Methods: Individuals of any age admitted to hospital because of vascular trauma in Ontario were included. Details of vascular injury and patient demographic characteristics were recorded, hospital admission rates estimated and analyses stratified by sex, age, mechanism of injury, economic status and geographic location. Time-series analysis was used to examine trends in hospital admission rates. Results: Of the 8252 hospital admissions for vascular trauma, 4287 (52.0%) involved injuries to the upper limb and 1819 (22.0%) were due to transport-related causes. Overall, the annual rate declined significantly over time, from 3.3 per 100 000 in 1991 to 2.7 per 100 000 in 2009 (p < 0.01). The subgroups with the highest rates were young men, patients with a low economic status and those living in a rural location. Declines occurred in both sexes and in all age groups except those 65 years and older. The rates of vascular injury to the neck, thorax, upper limbs and lower limbs declined over time, but not the rate of abdominal vascular injury. Although the rate of non-transport-related vascular injuries declined, the rate of transport-related vascular injuries did not change significantly over time. Decreases in annual rates occurred in both low- and high-economic status groups and in urban populations but not in rural populations. Interpretation: Overall, the annual rate of hospital admissions for vascular trauma declined significantly in Ontario over the study period. Our findings have important implications for public health and the development of injury-prevention strategies, particularly for population subgroups at high risk of vascular injury. PMID

  14. Long Term Population, City Size and Climate Trends in the Fertile Crescent: A First Approximation

    PubMed Central

    Lawrence, Dan; Philip, Graham; Hunt, Hannah; Snape-Kennedy, Lisa; Wilkinson, T. J.

    2016-01-01

    Over the last 8000 years the Fertile Crescent of the Near East has seen the emergence of urban agglomerations, small scale polities and large territorial empires, all of which had profound effects on settlement patterns. Computational approaches, including the use of remote sensing data, allow us to analyse these changes at unprecedented geographical and temporal scales. Here we employ these techniques to examine and compare long term trends in urbanisation, population and climate records. Maximum city size is used as a proxy for the intensity of urbanisation, whilst population trends are modelled from settlement densities in nine archaeological surveys conducted over the last 30 years across the region. These two measures are then compared with atmospheric moisture levels derived from multiple proxy analyses from two locations close to the study area, Soreq Cave in Israel and Lake Van in south-eastern Turkey, as well as wider literature. The earliest urban sites emerged during a period of relatively high atmospheric moisture levels and conform to a series of size thresholds. However, after the Early Bronze Age maximum urban size and population levels increase rapidly whilst atmospheric moisture declines. We argue that although the initial phase of urbanization may have been linked to climate conditions, we can see a definitive decoupling of climate and settlement patterns after 2000 BC. We relate this phenomenon to changes in socio-economic organisation and integration in large territorial empires. The complex relationships sustaining urban growth during this later period resulted in an increase in system fragility and ultimately impacted on the sustainability of cities in the long term. PMID:27018998

  15. Long-term population, productivity, and energy use trends in the sequence of leading capitalist nations.

    SciTech Connect

    LePoire, D. J.

    2010-10-01

    There are many theories on why sustainable science, technology, and commerce emerged first in Western Europe rather than elsewhere. A general theory is that the geography of Europe facilitated the development of diverse and independent states and resultant competition among them. Over the past 500 years, the sequence of leading states began with Portugal and the Netherlands on the edge of continental Western Europe, then moved to the British Isles, and finally moved across the Atlantic Ocean to the United States. The transitions of leadership from one state to another occurred about every 100 years. This sequence suggests that leadership moves from smaller states to larger states (although not to the largest existing state at the time), perhaps because larger states have the flexibility to develop more complex organizational processes and adapt new technology. To explore this theory further, this paper analyzes state population data at the beginning and end of each leadership period. The data reveal an accelerating initial population sequence. Further understanding is gained from comparing the populations of the preceding and succeeding states at the time of each transition: the succeeding state's population is usually about two times larger than that of the preceding state. It is also seen that over time, the new organizational processes and technologies developed by the leading state are diffused and adapted by other states. Evidence of the effects of this diffusion should be seen in the dynamics of relative productivity and energy use (since the relative advantage of new ideas and technology can be maintained for a short period of about 100 years). This paper investigates these trends in population, trade, and resources to provide insight on possible future transitions.

  16. Time trends in social differences in nutrition habits of a Lithuanian population: 1994-2010

    PubMed Central

    2012-01-01

    Background During the post-communist transition period, political, economic, and social changes affected the lifestyles of the Lithuanian population, including their nutritional habits. However, people of lower socio-economic position were more vulnerable to these changes. The aim of the present study was to evaluate the trends in selected food habits of the Lithuanian adult population by their level of education and place of residence from 1994 to 2010. Methods The data were obtained from nine biannual cross-sectional postal surveys of Lithuanian health behaviours, beginning in 1994. Each survey used a randomly selected nationally representative sample of 3000 inhabitants aged 20-64 drawn from the population register. In total, 7358 men and 9796 women participated in these surveys. Questions about food consumption were included within all health behaviour questionnaires. Results During the transition period, use of vegetable oil in cooking and the frequency of consumption of fresh vegetables increased, use of butter on bread decreased, and the proportion of women drinking high-fat milk declined. Lithuanians with higher education reported more frequent use of vegetable oil in cooking as well as daily consumption of fresh vegetables than those with a lower level of education. Consumption of high-fat milk was inversely associated with educational background. In addition, the proportion of persons spreading butter on bread increased with higher education level. The greatest urban-rural difference was observed in high-fat milk consumption. The increase in the use of vegetable oil in cooking, and the reduction of spreading butter on bread was more evident among less educated and rural inhabitants. Meanwhile, a greater proportion of the rural population, compared to urban, reduced their use of butter on bread. Daily consumption of fresh vegetables increased most among highly educated Lithuanians. Conclusions The data from our study indicate beneficial dietary changes

  17. Juvenile river herring habitat use and marine emigration trends: comparing populations.

    PubMed

    Turner, Sara M; Limburg, Karin E

    2016-01-01

    Juvenile habitat use and early life migratory behaviors of successfully recruited adult fish provide unique insight into critical habitats for a population, and this information allows restoration plans to be tailored to maximize benefits. Retrospective analysis of adult otolith chemistry combined with fish-otolith growth models were used to assess juvenile nursery habitat selection and size at egress to adult habitats (marine waters) for anadromous alewife and blueback herring from 20 rivers throughout the eastern US. Between-species differences in the size of emigrants were small, with blueback herring found in freshwater nurseries ~ 8% more frequently than alewives, and alewives using a combination of freshwater and estuarine nurseries ~ 9% more than bluebacks. Estuarine nursery use was more common in populations at lower latitudes. No clear trends in sizes of emigrants or habitat use were observed between the species in watersheds where both co-occur. Principal component analysis of latitude, watershed area, estuary area, accessible river kilometers, and percentage of the watershed in urban use indicated that the combined effects of these watershed characteristics were correlated with size at egress. These results highlight the considerable plasticity in early life habitat use among populations of anadromous fishes as well as the effect of watershed characteristics on early life migration timing and strategies. PMID:26369780

  18. Global dimming and urbanization: did stronger negative SSR trends collocate with regions of population growth?

    NASA Astrophysics Data System (ADS)

    Imamovic, Adel; Tanaka, Katsumasa; Folini, Doris; Wild, Martin

    2016-04-01

    Global dimming refers to the decrease in surface solar radiation (SSR) observed from the 1960s to the 1980s at different measurement sites all around the world. It is under debate whether anthropogenic aerosols emitted from urban areas close to the measurement sites are mainly responsible for the dimming. In order to assess this urbanization impact on SSR, we use spatially explicit population density data of 0.08° resolution to construct population indices (PI) at 157 high data quality sites. Our study extends previous population-based studies by incorporating distance-weighting as a simple aerosol diffusion model. We measured urbanization in the surrounding of a site as the PI change form 1960 to 1990 and found no negative correlation with the corresponding SSR trends from 1964 to 1989 for the 92 sites in Europe and Japan. For the 39 sites in China the correlation coefficients are significant at the 5 % level and reach around ‑0.35, while for the 26 remaining Asian, mostly Russian sites the correlation coefficients reach around ‑0.55 at the 1 % significance level. Results are similar, when the absolute levels of PIs are taken as an indicator for urbanization. Our findings call into question the existence of an urbanization effect for the sites in Europe and Japan, while such an effect cannot be ruled out for the sites in Asia, especially in Russia.

  19. Global dimming and urbanization: did stronger negative SSR trends collocate with regions of population growth?

    NASA Astrophysics Data System (ADS)

    Imamovic, A.; Tanaka, K.; Folini, D.; Wild, M.

    2015-11-01

    Global dimming refers to the decrease in surface solar radiation (SSR) observed from the 1960s to the 1980s at different measurement sites all around the world. It is under debate whether anthropogenic aerosols emitted from urban areas close to the measurement sites are mainly responsible for the dimming. In order to assess this urbanization impact on SSR, we use spatially explicit population density data of 0.08° resolution to construct population indices (PI) at 157 high data quality sites. Our study extends previous population-based studies by incorporating distance-weighting as a simple aerosol diffusion model. We measured urbanization in the surrounding of a site as the PI change form 1960 to 1990 and found no negative correlation with the corresponding SSR trends from 1964 to 1989 for the 92 sites in Europe and Japan. For the 39 sites in China the correlation coefficients are significant at the 5 % level and reach around -0.35, while for the 26 remaining Asian, mostly Russian sites the correlation coefficients reach around -0.55 at the 1 % significance level. Results are similar, when the absolute levels of PIs are taken as an indicator for urbanization. Our findings call into question the existence of an urbanization effect for the sites in Europe and Japan, while such an effect cannot be ruled out for the sites in Asia, especially in Russia.

  20. Global dimming and urbanization: did stronger negative SSR trends collocate with regions of population growth?

    NASA Astrophysics Data System (ADS)

    Imamovic, Adel; Tanaka, Katsumasa; Folini, Doris; Wild, Martin

    2016-03-01

    Global dimming refers to the decrease in surface solar radiation (SSR) observed from the 1960s to the 1980s at different measurement sites all around the world. It is under debate whether anthropogenic aerosols emitted from urban areas close to the measurement sites are mainly responsible for the dimming. In order to assess this urbanization impact on SSR, we use spatially explicit population density data of 0.08° resolution to construct population indices (PI) at 157 high data quality sites. Our study extends previous population-based studies by incorporating distance-weighting as a simple aerosol diffusion model. We measured urbanization in the surrounding of a site as the PI change from 1960 to 1990 and found no negative correlation with the corresponding SSR trends from 1964 to 1989 for the 92 sites in Europe and Japan. For the 39 sites in China the correlation coefficients are significant at the 5 % level and reach around -0.35, while for the 26 remaining Asian, mostly Russian sites the correlation coefficients reach around -0.55 at the 1 % significance level. Results are similar, when the absolute levels of PIs are taken as an indicator for urbanization. Our findings call into question the existence of an urbanization effect for the sites in Europe and Japan, while such an effect cannot be ruled out for the sites in Asia, especially in Russia.

  1. Red-shouldered hawk broadcast surveys: Factors affecting detection of responses and population trends

    USGS Publications Warehouse

    McLeod, M.A.; Andersen, D.E.

    1998-01-01

    Forest-nesting raptors are often difficult to detect and monitor because they can be secretive, and their nests can be difficult to locate. Some species, however, respond to broadcasts of taped calls, and these responses may be useful both in monitoring population trends and in locating nests. We conducted broadcast surveys on roads and at active red-shouldered hawk (Buteo lineatus) nests in northcentral Minnesota to determine effects of type of call (conspecific or great horned owl [Bubo virginianus]), time of day, and phase of the breeding cycle on red-shouldered hawk response behavior and to evaluate usefulness of broadcasts as a population monitoring tool using area occupied-probability-of-detection techniques. During the breeding seasons of 1994 and 1995, we surveyed 4 10-station road transects 59 times and conducted 76 surveys at 24 active nests. Results of these surveys indicated conspecific calls broadcast prior to hatch and early in the day were the most effective method of detecting red-shouldered hawks. Probability of detection via conspecific calls averaged 0.25, and area occupied was 100%. Computer simulations using these field data indicated broadcast surveys have the potential to be used as a population monitoring tool.

  2. River dolphins can act as population trend indicators in degraded freshwater systems.

    PubMed

    Turvey, Samuel T; Risley, Claire L; Barrett, Leigh A; Yujiang, Hao; Ding, Wang

    2012-01-01

    Conservation attention on charismatic large vertebrates such as dolphins is often supported by the suggestion that these species represent surrogates for wider biodiversity, or act as indicators of ecosystem health. However, their capacity to act as indicators of patterns or trends in regional biodiversity has rarely been tested. An extensive new dataset of >300 last-sighting records for the Yangtze River dolphin or baiji and two formerly economically important fishes, the Yangtze paddlefish and Reeves' shad, all of which are probably now extinct in the Yangtze, was collected during an interview survey of fishing communities across the middle-lower Yangtze drainage. Untransformed last-sighting date frequency distributions for these species show similar decline curves over time, and the linear gradients of transformed last-sighting date series are not significantly different from each other, demonstrating that these species experienced correlated population declines in both timing and rate of decline. Whereas species may be expected to respond differently at the population level even in highly degraded ecosystems, highly vulnerable (e.g. migratory) species can therefore display very similar responses to extrinsic threats, even if they represent otherwise very different taxonomic, biological and ecological groupings. Monitoring the status of river dolphins or other megafauna therefore has the potential to provide wider information on the status of other threatened components of sympatric freshwater biotas, and so represents a potentially important monitoring tool for conservation management. We also show that interview surveys can provide robust quantitative data on relative population dynamics of different species. PMID:22666410

  3. The Power to Detect Trends in Missouri River Fish Populations within the Pallid Sturgeon Population Assessment Program

    USGS Publications Warehouse

    Bryan, Janice L.; Wildhaber, Mark L.; Gladish, Dan; Holan, Scott; Ellerseick, Mark

    2010-01-01

    pallid sturgeon models was not as high as other species at the current level of sampling, but an increase in the sampling effort to 16 subsamples for each of 24 bends for 20 years would generate adequate power for the pallid sturgeon in all Zones. Since gear types are selective in their species efficiency, the strength of the Pallid Sturgeon Population Assessment Program approach is using multiple gears that have statistical power to detect population trends at the same time in different fish species within the Missouri River. As often is the case with monitoring studies involving endangered species, the data used to conduct the analyses exhibit some departures from the parametric model assumptions; however, preliminary simulations indicate that the results of this study are appropriate.

  4. Trends of Increasing Medical Radiation Exposure in a Population Hospitalized for Cardiovascular Disease (1970–2009)

    PubMed Central

    Carpeggiani, Clara; Landi, Patrizia; Michelassi, Claudio; Marraccini, Paolo; Picano, Eugenio

    2012-01-01

    Background High radiation doses employed in cardiac imaging may increase cancer frequency in exposed patients after decades. The aim of this study was to evaluate the relative trends in medical radiation exposure in a population hospitalized for cardiovascular disease. Methods and Results An observational single-center study was conducted to examine 16,431 consecutive patients with heart disease admitted to the Italian National Research Council Institute of Clinical Physiology between January 1970 and December 2009. In all patients, the cumulative estimated effective dose was obtained from data mining of electronic records of hospital admissions, adopting the effective dose typical values of the American Heart Association 2009 statement and Mettler’s 2008 catalog of doses. Cumulative estimated effective dose per patient in the last 5 years was 22 (12–42) mSv (median, 25th–75th percentiles), with higher values in ischemic heart disease (IHD), 37 (20–59) vs non-IHD, 13 (8–22) mSv, p<0.001. Trends in radiation exposure showed a steady increase in IHD and a flat trend in non-IHD patients, with variation from 1970–74 to 2005–2009 of +155% for IHD (p<0.001) and −1% in non-IHD (NS). The relative contribution of different imaging techniques was remodeled over time, with nuclear cardiology dominating in 1970s (23% of individual exposure) and invasive fluoroscopy in the last decade (90% of individual exposure). Conclusion A progressive increase in cumulative estimated effective dose is observed in hospitalized IHD patients. The growing medical radiation exposure may encourage a more careful justification policy regarding ionizing imaging in cardiology patients applying the two main principles of radiation protection: appropriate justification for ordering and performing each procedure, and careful optimization of the radiation dose used during each procedure. PMID:23209665

  5. Time trends in fish populations in metropolitan France: insights from national monitoring data.

    PubMed

    Poulet, N; Beaulaton, L; Dembski, S

    2011-12-01

    Using the electrofishing database of the French National Agency for Water and Aquatic Environment (Onema), the time trends of 48 freshwater fish taxa at 590 sites monitored for at least 8 years from 1990 to 2009 were investigated. The results demonstrated that species richness increased steadily from the beginning of the monitoring period. This is congruent with the finding that the number of species displaying a significant increase in spatial distribution or abundance was greater than those showing a significant decrease. Some species, however, had declined both in occurrence and abundance, e.g. tench Tinca tinca, common bream Abramis brama, brown trout Salmo trutta and European eel Anguilla anguilla. The species showing the most spectacular colonization were non-native, e.g. topmouth gudgeon Pseudorasbora parva, wels catfish Silurus glanis and asp Aspius aspius. The time trends in population density were related to the maximal body size, habitat requirement, occurrence and abundance and the status (i.e. native or exotic) but not to the spawning temperature. PMID:22136235

  6. Assessing the status and trend of bat populations across broad geographic regions with dynamic distribution models

    USGS Publications Warehouse

    Rodhouse, Thomas J.; Ormsbee, Patricia C.; Irvine, Kathryn M.; Vierling, Lee A.; Szewczak, Joseph M.; Vierling, Kerri T.

    2012-01-01

    Despite its common status, M. lucifugus was only detected during ∼50% of the surveys in occupied sample units. The overall naïve estimate for the proportion of the study region occupied by the species was 0.69, but after accounting for imperfect detection, this increased to ∼0.90. Our models provide evidence of an association between NPP and forest cover and M. lucifugus distribution, with implications for the projected effects of accelerated climate change in the region, which include net aridification as snowpack and stream flows decline. Annual turnover, the probability that an occupied sample unit was a newly occupied one, was estimated to be low (∼0.04–0.14), resulting in flat trend estimated with relatively high precision (SD = 0.04). We mapped the variation in predicted occurrence probabilities and corresponding prediction uncertainty along the productivity gradient. Our results provide a much needed baseline against which future anticipated declines in M. lucifugus occurrence can be measured. The dynamic distribution modeling approach has broad applicability to regional bat monitoring efforts now underway in several countries and we suggest ways to improve and expand our grid-based monitoring program to gain robust insights into bat population status and trend across large portions of North America.

  7. Time trends of antidepressant drug prescriptions in men versus women in a geographically defined US population

    PubMed Central

    Zhong, Wenjun; Kremers, Hilal Maradit; Yawn, Barbara P.; Bobo, William V.; St Sauver, Jennifer L.; Ebbert, Jon O.; Rutten, Lila J.; Jacobson, Debra J.; Brue, Scott M.; Rocca, Walter A.

    2014-01-01

    Purpose To study time trends of antidepressant drug (AD) prescriptions in a geographically defined US population between 2005 and 2011 for men and women separately. Methods Using the Rochester Epidemiology Project medical records-linkage system, we identified all Olmsted County, MN residents who received AD outpatient prescriptions between 2005 and 2011 (seven years). We calculated the annual age-and sex-specific prevalence over seven years, and used generalized estimating equation models to test for time trends. Results The prevalence of subjects receiving at least one AD prescription was approximately two times higher in women than men consistently across the seven years of the study. The standardized annual prevalence increased from 10.8% in 2005 to 14.4% in 2011 overall, from 7.0% in 2005 to 9.9% in 2011 for men, and from 14.4% in 2005 to 18.6% in 2011 for women. The absolute percent increase was greater in women (4.2% vs. 2.9%; standardized); however, the relative percent increase was greater in men (41.4% vs. 29.2%; standardized). The relative percent increase was greater in the age group 65+ years for both men and women. Conclusions AD prescriptions are increasing over time, especially in the elderly. Women receive more AD prescriptions than men. However, the relative increase in AD prescriptions over time is greater in men than women. PMID:25113318

  8. Christmas Island birds returning

    NASA Astrophysics Data System (ADS)

    Six months after their mass exodus, birds are beginning to return to Christmas Island. Roughly 17 million birds, almost the entire adult bird population, either perished or fled their mid-Pacific atoll home last autumn, leaving behind thousands of nestlings to starve (Eos, April 5, 1983, p. 131). It is believed that the strong El Niño altered the ecology of the surrounding waters and forced the birds to flee. Christmas Island is the world's largest coral atoll.“Ocean and atmosphere scientists are unsure of future directions for the El Niño conditions and cannot now predict what will happen to the birds in the coming months,” said Ralph W. Schreiber, curator of ornithology at the Natural History Museum of Los Angeles County in California. Heisthe ornithologist who discovered the disappearance. “The recovery of the bird populations depends on the food supply in the waters surrounding the island.” The island's birds feed exclusively on small fish and squid.

  9. Hierarchical models and the analysis of bird survey information

    USGS Publications Warehouse

    Sauer, J.R.; Link, W.A.

    2003-01-01

    Management of birds often requires analysis of collections of estimates. We describe a hierarchical modeling approach to the analysis of these data, in which parameters associated with the individual species estimates are treated as random variables, and probability statements are made about the species parameters conditioned on the data. A Markov-Chain Monte Carlo (MCMC) procedure is used to fit the hierarchical model. This approach is computer intensive, and is based upon simulation. MCMC allows for estimation both of parameters and of derived statistics. To illustrate the application of this method, we use the case in which we are interested in attributes of a collection of estimates of population change. Using data for 28 species of grassland-breeding birds from the North American Breeding Bird Survey, we estimate the number of species with increasing populations, provide precision-adjusted rankings of species trends, and describe a measure of population stability as the probability that the trend for a species is within a certain interval. Hierarchical models can be applied to a variety of bird survey applications, and we are investigating their use in estimation of population change from survey data.

  10. Normalized Diurnal and Between-Day Trends in Illicit and Legal Drug Loads that Account for Changes in Population

    PubMed Central

    Brewer, Alex J.; Ort, Christoph; Banta-Green, Caleb J.; Berset, Jean-Daniel

    2012-01-01

    Drug concentrations in composite municipal wastewater samples and census-based estimates of population are used to derive daily loads of illicit substances that are indexed to population. However, such estimates do not provide information on the diurnal trends of substance excretion nor can they account for changes in population. To address these limitations, a series of 1 h composites created by sampling wastewater influent at 6 min intervals was collected over four consecutive days at a single wastewater treatment plant. Creatinine (a urinary indicator), caffeine, methamphetamine, benzoylecgonine (BZE), and cocaine were analyzed by liquid chromatography/tandem mass spectrometry (LC-MS/MS). Diurnal trends and between-day trends were substance specific and related to the number of estimated doses and excretory half-life. Normalization to creatinine yielded trends in substances that differed significantly from non-normalized trends by accounting for changes in population within the municipality studied. Increases in normalized substance excretion observed during early morning hours originate from individuals among the resident population of the municipality due to the absence of commuters. PMID:22804833

  11. A hierarchical model for regional analysis of population change using Christmas Bird Count data, with application to the American Black Duck

    USGS Publications Warehouse

    Link, W.A.; Sauer, J.R.; Niven, D.K.

    2006-01-01

    Analysis of Christmas Bird Count (CBC) data is complicated by the need to account for variation in effort on counts and to provide summaries over large geographic regions. We describe a hierarchical model for analysis of population change using CBC data that addresses these needs. The effect of effort is modeled parametrically, with parameter values varying among strata as identically distributed random effects. Year and site effects are modeled hierarchically, accommodating large regional variation in number of samples and precision of estimates. The resulting model is complex, but a Bayesian analysis can be conducted using Markov chain Monte Carlo techniques. We analyze CBC data for American Black Ducks (Anas rubripes), a species of considerable management interest that has historically been monitored using winter surveys. Over the interval 1966-2003, Black Duck populations showed distinct regional patterns of population change. The patterns shown by CBC data are similar to those shown by the Midwinter Waterfowl Inventory for the United States.

  12. The Climate-Population Nexus in the East African Horn: Emerging Degradation Trends in Rangeland and Pastoral Livelihood Zones

    NASA Astrophysics Data System (ADS)

    Pricope, N. G.; Husak, G. J.; Funk, C. C.; Lopez-Carr, D.

    2014-12-01

    Increasing climate variability and extreme weather conditions along with declining trends in both rainfall and temperature represent major risk factors affecting agricultural production and food security in many regions of the world. We identify regions where significant rainfall decrease from 1979-2011 over the entire continent of Africa couples with significant human population density increase. The rangelands of Ethiopia, Kenya, and Somalia in the East African Horn remain one of the world's most food insecure regions, yet have significantly increasing human populations predominantly dependent on pastoralist and agro-pastoralist livelihoods. Vegetation in this region is characterized by a variable mosaic of land covers, generally dominated by grasslands necessary for agro-pastoralism, interspersed by woody vegetation. Recent assessments indicate that widespread degradation is occurring, adversely impacting fragile ecosystems and human livelihoods. Using two underutilized MODIS products, we observe significant changes in vegetation patterns and productivity over the last decade all across the East African Horn. We observe significant vegetation browning trends in areas experiencing drying precipitation trends in addition to increasing population pressures. We also found that the drying precipitation trends only partially statistically explain the vegetation browning trends, further indicating that other factors such as population pressures and land use changes are responsible for the observed declining vegetation health. Furthermore, we show that the general vegetation browning trends persist even during years with normal rainfall conditions such as 2012, indicating potential long-term degradation of rangelands on which approximately 10 million people depend. These findings have serious implications for current and future regional food security monitoring and forecasting as well as for mitigation and adaptation strategies in a region where population is expected

  13. Status of forest birds on Rota, Mariana Islands

    USGS Publications Warehouse

    Camp, Richard J.; Brinck, Kevin W.; Gorresen, P. Marcos; Amidon, Fred A.; Radley, Paul M.; Berkowitz, S. Paul; Banko, Paul C.

    2014-01-01

    The western Pacific island of Rota is the third largest human inhabited island in the Mariana archipelago, and is designated an Endemic Bird Area. Between 1982 and 2012, 12 point-transect distance sampling surveys were conducted to assess population status. Surveys did not consistently sample the entire island; thus, we used a ratio estimator to estimate bird abundances in strata not sampled during every survey. Occupancy models of the 2012 survey revealed general patterns of habitat use and detectability among 11 species that could be reliably modeled. The endangered Mariana crow (Corvus kubaryi) was dispersed around the periphery of the island in steep forested habitats. In contrast, the endangered Rota white-eye (Zosterops rotensis) was restricted to the high-elevation mesa. Precision of detection probabilities and occupancy estimates and effects of habitat types, sampling conditions, and specific observers varied considerably among species, indicating that more narrowly defined classifications and additional observer training may improve the accuracy of predictive modeling. Population estimates of five out of ten native bird species, including collared kingfisher (Todiramphus chloris orii), Mariana crow, Mariana fruit-dove (Ptilinopus roseicapilla), Micronesian myzomela (Myzomela rubrata), and white-throated ground-dove (Gallicolumba xanthonura) declined over the 30-year time series. The crow declined sharply to fewer than 200 individuals (upper 95% confidence interval). Trends increased for Micronesian starling (Aplonis opaca), rufous fantail (Rhipidura rufifrons mariae), and white tern (Gygis alba). Rota white-eye numbers declined from 1982 to the late 1990s, but returned to 1980s levels by 2012. The trend for the yellow bittern (Ixobrychus sinensis) was inconclusive. The alien Eurasian tree sparrow (Passer montanus) apparently increased in number despite an unreliable trend assessment. Declines were noted in the other two alien birds, black drongo (Dicrurus

  14. Population income and longitudinal trends in living kidney donation in the United States.

    PubMed

    Gill, Jagbir; Dong, Jianghu; Gill, John

    2015-01-01

    Living kidney donation is declining in the United States. We examined longitudinal trends in living donation as a function of median household income and donor relation to assess the effect of financial barriers on donation in a changing economic environment. The zip code-level median household income of all 71,882 living donors was determined by linkage to the 2000 US Census. Longitudinal changes in the rate of donation were determined in income quintiles between 1999 and 2004, when donations were increasing, and between 2005 and 2010, when donations were declining. Rates were adjusted for population differences in age, sex, race, and ESRD rate using multilevel linear regression models. Between 1999 and 2004, the rate of growth in living donation per million population was directly related to income, increasing progressively from the lowest to highest income quintile, with annualized changes of 0.55 (95% confidence interval [95% CI], 0.14 to 1.05) for Q1 and 1.77 (95% CI, 0.66 to 2.77) for Q5 (P<0.05). Between 2005 and 2010, donation declined in Q1, Q2, and Q3; was stable in Q4; and continued to grow in Q5. Longitudinal changes varied by donor relationship, and the association of income with longitudinal changes also varied by donor relationship. In conclusion, changes in living donation in the past decade varied by median household income, resulting in increased disparities in donation between low- and high-income populations. These findings may inform public policies to support living donation during periods of economic volatility. PMID:25035519

  15. Global Population Trends and Human Use Patterns of Manta and Mobula Rays

    PubMed Central

    Ward-Paige, Christine A.; Davis, Brendal; Worm, Boris

    2013-01-01

    Despite being the world’s largest rays and providing significant revenue through dive tourism, little is known about the population status, exploitation and trade volume of the Mobulidae (mobulids; Manta and Mobula spp.). There is anecdotal evidence, however, that mobulid populations are declining, largely due to the recent emergence of a widespread trade for their gill rakers, which is reflected in increasing Food and Agriculture Organization landings trends. Here, we present results from two dedicated diver surveys, one from the eManta project, which includes summary observations from ninety 10°x10° regions with ∼200–62,000 dives per region, and the other from the Reef Environmental Education Foundation, which includes spatially more detailed observations from 3 regions with ∼4,000–118,000 dives per region. We show that mobulids as a group, which includes eleven species, have globally and regionally restricted distributions, typically have low sighting frequency (<1% of dives) and aggregate in only a few locations. Of the regions surveyed by divers, almost half (47%) report declining mobulid sightings over the last decade. Divers indicate that although mobulid ecotourism occurs in many regions (45% of those reported, n = 41) they are considered protected in only 32% of the regions. Mobulids being fished or sold in local markets were reported from 16% and 12% of regions, respectively, with most being adjacent to mobulid abundance hotspot and ecotourism regions (e.g. Sri Lanka, Indonesia, east Africa). Identification of regions where ecotourism and exploitation are at odds could help prioritize conservation efforts. Vulnerability analysis, using life history characteristics, indicates that Manta spp. are vulnerable to exploitation, tolerating only low fishing mortality rates; data limitations prohibited such analysis for Mobula spp. Our analyses support previous studies in showing the need for improved conservation and monitoring efforts, and

  16. Global population trends and human use patterns of Manta and Mobula rays.

    PubMed

    Ward-Paige, Christine A; Davis, Brendal; Worm, Boris

    2013-01-01

    Despite being the world's largest rays and providing significant revenue through dive tourism, little is known about the population status, exploitation and trade volume of the Mobulidae (mobulids; Manta and Mobula spp.). There is anecdotal evidence, however, that mobulid populations are declining, largely due to the recent emergence of a widespread trade for their gill rakers, which is reflected in increasing Food and Agriculture Organization landings trends. Here, we present results from two dedicated diver surveys, one from the eManta project, which includes summary observations from ninety 10°x10° regions with ∼200-62,000 dives per region, and the other from the Reef Environmental Education Foundation, which includes spatially more detailed observations from 3 regions with ∼4,000-118,000 dives per region. We show that mobulids as a group, which includes eleven species, have globally and regionally restricted distributions, typically have low sighting frequency (<1% of dives) and aggregate in only a few locations. Of the regions surveyed by divers, almost half (47%) report declining mobulid sightings over the last decade. Divers indicate that although mobulid ecotourism occurs in many regions (45% of those reported, n = 41) they are considered protected in only 32% of the regions. Mobulids being fished or sold in local markets were reported from 16% and 12% of regions, respectively, with most being adjacent to mobulid abundance hotspot and ecotourism regions (e.g. Sri Lanka, Indonesia, east Africa). Identification of regions where ecotourism and exploitation are at odds could help prioritize conservation efforts. Vulnerability analysis, using life history characteristics, indicates that Manta spp. are vulnerable to exploitation, tolerating only low fishing mortality rates; data limitations prohibited such analysis for Mobula spp. Our analyses support previous studies in showing the need for improved conservation and monitoring efforts, and suggest that

  17. Time trends in burdens of cadmium, lead, and mercury in the population of northern Sweden

    SciTech Connect

    Wennberg, Maria . E-mail: miawennberg@skehus19.ac; Lundh, Thomas; Bergdahl, Ingvar A.; Hallmans, Goeran; Jansson, Jan-Hakan; Stegmayr, Birgitta; Custodio, Hipolito M.; Skerfving, Staffan

    2006-03-15

    The time trends of exposure to heavy metals are not adequately known. This is a worldwide problem with regard to the basis for preventive actions and evaluation of their effects. This study addresses time trends for the three toxic elements cadmium (Cd), mercury (Hg), and lead (Pb). Concentrations in erythrocytes (Ery) were determined in a subsample of the population-based MONICA surveys from 1990, 1994, and 1999 in a total of 600 men and women aged 25-74 years. The study took place in the two northernmost counties in Sweden. To assess the effect of changes in the environment, adjustments were made for life-style factors that are determinants of exposure. Annual decreases of 5-6% were seen for Ery-Pb levels (adjusted for age and changes in alcohol intake) and Ery-Hg levels (adjusted for age and changes in fish intake). Ery-Cd levels (adjusted for age) showed a similar significant decrease in smoking men. It is concluded that for Pb and maybe also Hg the actions against pollution during recent decades have caused a rapid decrease of exposure; for Hg the decreased use of dental amalgam may also have had an influence. For Cd, the decline in Ery-Cd was seen only in smokers, indicating that Cd exposure from tobacco has decreased, while other environmental sources of Cd have not changed significantly. To further improve the health status in Sweden, it is important to decrease the pollution of Cd, and actions against smoking in the community are important.

  18. Trends in amenable mortality rate in the Mongolian population, 2007-2014.

    PubMed

    Surenjav, Enkhjin; Sovd, Tugsdelger; Yoshida, Yoshitoku; Yamamoto, Eiko; Reyer, Joshua A; Hamajima, Nobuyuki

    2016-02-01

    Amenable mortality (AM) is an indicator of medical care quality. This study aimed to assess the trend and magnitude of AM in Mongolia, with the purpose of providing evidence for decisions on resource allocation. This is the first study on AM trends in Mongolia. Retrospective analysis was done on mortality statistics for the period 2007-2014. Causes of death were coded according to the 10th revision of the International Classification of Diseases (ICD-10). Nolte & McKee's classification of AM was used for the estimation of amenable mortality rates (AMRs) in Mongolia. During the study period, a total of 130,402 deaths were registered in Mongolia, of which 44,800 (34.4%) deaths were classified as being amenable. The age-standardized AMR per 100,000 population was highest in 2007 (226.6), and declined continuously until the level of 169.2 in 2014. The rate remained consistently higher in males than in females. Cerebrovascular diseases, ischemic heart diseases, perinatal deaths, influenza/pneumonia/asthma and tuberculosis were the leading causes of AM in the past eight years in Mongolia. The AMR was higher in remote western provinces with harsh weather conditions, high poverty rates, lack of human resources for health, and poor infrastructure. In addition, the provinces where Mongolia's ethnic minorities live tended to have a higher AMR. The government of Mongolia needs to critically look at the regional differences in AM in order to allocate health resources, including human resources, effectively. Further studies are needed to look into the causes of regional disparities in AM, individual-level risk factors to amenable deaths, and validity of death coding in health sector. PMID:27019528

  19. Trends in amenable mortality rate in the Mongolian population, 2007–2014

    PubMed Central

    Surenjav, Enkhjin; Sovd, Tugsdelger; Yoshida, Yoshitoku; Yamamoto, Eiko; Reyer, Joshua A.; Hamajima, Nobuyuki

    2016-01-01

    ABSTRACT Amenable mortality (AM) is an indicator of medical care quality. This study aimed to assess the trend and magnitude of AM in Mongolia, with the purpose of providing evidence for decisions on resource allocation. This is the first study on AM trends in Mongolia. Retrospective analysis was done on mortality statistics for the period 2007–2014. Causes of death were coded according to the 10th revision of the International Classification of Diseases (ICD-10). Nolte & McKee’s classification of AM was used for the estimation of amenable mortality rates (AMRs) in Mongolia. During the study period, a total of 130,402 deaths were registered in Mongolia, of which 44,800 (34.4%) deaths were classified as being amenable. The age-standardized AMR per 100,000 population was highest in 2007 (226.6), and declined continuously until the level of 169.2 in 2014. The rate remained consistently higher in males than in females. Cerebrovascular diseases, ischemic heart diseases, perinatal deaths, influenza/pneumonia/asthma and tuberculosis were the leading causes of AM in the past eight years in Mongolia. The AMR was higher in remote western provinces with harsh weather conditions, high poverty rates, lack of human resources for health, and poor infrastructure. In addition, the provinces where Mongolia’s ethnic minorities live tended to have a higher AMR. The government of Mongolia needs to critically look at the regional differences in AM in order to allocate health resources, including human resources, effectively. Further studies are needed to look into the causes of regional disparities in AM, individual-level risk factors to amenable deaths, and validity of death coding in health sector. PMID:27019528

  20. Age Specific Survival Rates of Steller Sea Lions at Rookeries with Divergent Population Trends in the Russian Far East

    PubMed Central

    Altukhov, Alexey V.; Andrews, Russel D.; Calkins, Donald G.; Gelatt, Thomas S.; Gurarie, Eliezer D.; Loughlin, Thomas R.; Mamaev, Evgeny G.; Nikulin, Victor S.; Permyakov, Peter A.; Ryazanov, Sergey D.; Vertyankin, Vladimir V.; Burkanov, Vladimir N.

    2015-01-01

    After a dramatic population decline, Steller sea lions have begun to recover throughout most of their range. However, Steller sea lions in the Western Aleutians and Commander Islands are continuing to decline. Comparing survival rates between regions with different population trends may provide insights into the factors driving the dynamics, but published data on vital rates have been extremely scarce, especially in regions where the populations are still declining. Fortunately, an unprecedented dataset of marked Steller sea lions at rookeries in the Russian Far East is available, allowing us to determine age and sex specific survival in sea lions up to 22 years old. We focused on survival rates in three areas in the Russian range with differing population trends: the Commander Islands (Medny Island rookery), Eastern Kamchatka (Kozlov Cape rookery) and the Kuril Islands (four rookeries). Survival rates differed between these three regions, though not necessarily as predicted by population trends. Pup survival was higher where the populations were declining (Medny Island) or not recovering (Kozlov Cape) than in all Kuril Island rookeries. The lowest adult (> 3 years old) female survival was found on Medny Island and this may be responsible for the continued population decline there. However, the highest adult survival was found at Kozlov Cape, not in the Kuril Islands where the population is increasing, so we suggest that differences in birth rates might be an important driver of these divergent population trends. High pup survival on the Commander Islands and Kamchatka Coast may be a consequence of less frequent (e.g. biennial) reproduction there, which may permit females that skip birth years to invest more in their offspring, leading to higher pup survival, but this hypothesis awaits measurement of birth rates in these areas. PMID:26016772

  1. Power analysis to detect time trends on population-based cancer registries data: When size really matters.

    PubMed

    Zanetti, Roberto; Sera, Francesco; Sacchetto, Lidia; Coebergh, Jan Willem; Rosso, Stefano

    2015-06-01

    Detecting statistically significant trends in incidence with cancer registries data not only depends on the size of their covered population but also on the levels of incidence rates, duration of diagnostic period and type of temporal variation. We simulated sample sizes of newly diagnosed cases based on a variety of plausible levels of cancer rates and scenarios of changing trends over a period of about 30 years. Each simulated set of cases was then analysed with joinpoint regression models. The power was derived as the relative frequency of the simulation runs where the p-value of the coefficient was less than 0.05 under the alternative model. In case of a decreasing trend with no change of direction (join), an Annual Percentage Change (APC) of 1% for an average rate of 10 per 100,000 is detectable in populations of half a million inhabitants or more with a nominal power of 80%. In a model with one joinpoint followed by an increasing trend, the minimum detectable APC increases, and an APC of about 2%, can be detected only with populations of at least 2 million. For analyses requiring a larger sample size than the actual covered population, alternative organisational strategies should be considered, such as an extension of population coverage or data pooling and merging from registries with comparable data. (i.e. when heterogeneity across merging registries is low or acceptable for the specific study question). PMID:24239127

  2. Population trends of San Joaquin kit fox (Vulpes velox macrotis) at Camp Roberts Army National Guard Training Site, California

    SciTech Connect

    Berry, W.H.; Standley, W.G.

    1992-10-01

    Population trends of a San Joaquin kit fox population (Vulpes velox macrotis) were investigated at Camp Roberts Army National Guard Training Site, California, from November 1989 through August 1991. Six semiannual livetrapping sessions and eight scent-station survey sessions were conducted. Livetrapping results and radiotelemetry data were used to calculate minimum population size, density, and distribution. A total of 175 individual foxes were trapped 463 times. The number of individuals trapped and minimum population size calculations showed a decline over time. The highest minimum population (109) was observed in winter 1988. Summer 1991 had the lowest minimum population size (45). No evidence was found to indicate that the apparent population decline was a result of military-authorized activities.

  3. eHealth Trends in Europe 2005-2007: A Population-Based Survey

    PubMed Central

    Chronaki, Catherine E; Lausen, Berthold; Prokosch, Hans-Ulrich; Rasmussen, Janne; Santana, Silvina; Staniszewski, Andrzej; Wangberg, Silje Camilla

    2008-01-01

    Background In the last decade, the number of Internet users worldwide has dramatically increased. People are using the Internet for various health-related purposes. It is important to monitor such use as it may have an impact on the individual’s health and behavior, patient-practitioner roles, and on general health care provision. Objectives This study investigates trends and patterns of European health-related Internet use over a period of 18 months. The main study objective was to estimate the change in the proportion of the population using the Internet for health purposes, and the importance of the Internet as a source of health information compared to more traditional sources. Methods The survey data were collected through computer-assisted telephone interviews. A representative sample (N = 14,956) from seven European countries has been used: Denmark, Germany, Greece, Latvia, Norway, Poland, and Portugal. The European eHealth Consumer Trends Survey was first conducted in October-November 2005 and repeated in April-May 2007. In addition to providing background information, respondents were asked to rate the importance of various sources of health information. They were also queried as to the frequency of different online activities related to health and illness and the effects of such use on their disposition. Results The percentage of the population that has used the Internet for health purposes increased from an estimated 42.3% (95% CI [Confidence Interval] 41.3 - 43.3) in 2005 to an estimated 52.2% (95% CI 51.3 - 53.2) in 2007. Significant growth in the use of the Internet for health purposes was found in all the seven countries. Young women are the most active Internet health users. The importance of the Internet as a source of health information has increased. In 2007, the Internet was perceived as an important source of health information by an estimated 46.8% (95% CI 45.7 - 47.9) of the population, a significant increase of 6.5 % (95% CI 4.9 - 8

  4. Contrasting population trends of piscivorous seabirds in the Pribilof Islands: A 30-year perspective

    USGS Publications Warehouse

    Byrd, G.V.; Schmutz, J.A.; Renner, H.M.

    2008-01-01

    The Pribilof Islands provide nesting habitat for one of the largest concentrations of piscivorous seabirds in the North Pacific region. Pribilof breeding populations of black-legged and red-legged kittiwakes (Rissa tridactyla and Rissa brevirostris), and common and thick-billed murres (Uria aalge and Uria lomvia) are supported by a highly productive marine food web. Productivity and temperature in this area are influenced by winter sea ice that frequently reaches its maximum extent near the Pribilofs. Although St. George and St. Paul islands, the two largest of the Pribilof group, are situated only 60 km apart, St. George is within 25 km of the shelf break, but St. Paul is approximately 90 km away. In contrast, the local contribution of sea ice-edge productivity in the spring is frequently closer to St. Paul than to St. George. Central place foraging piscivorous seabirds nesting at St. Paul and St. George are likely differentially affected by the relative contributions of the shelf break and ice-edge environments based on juxtaposition. Within the past decade or so, sea ice in the Bering Sea has failed to reach the vicinity of the Pribilofs in some years, and predictions of warming in the future suggest the possibility that direct effects of the ice on the immediate Pribilof environment will be reduced. To evaluate the response of kittiwakes and murres on the two islands to conditions in their foraging environments, we examined population trends over the past 30 years based on data from the seabird monitoring program conducted by the Alaska Maritime National Wildlife Refuge and others. Spatial differences in trends have been more consistent than differences among species, with populations at St. Paul having more enduring declines than those at St. George. At St. George, black-legged kittiwakes and common murres have remained stable. Red-legged kittiwakes and thick-billed murres both declined, but began to rebound in the late 1980s, such that in 2005 population

  5. Trends in use of neonatal CPAP: a population-based study

    PubMed Central

    2011-01-01

    Background Continuous positive airway pressure (CPAP) is used widely to provide respiratory support for neonates, and is often the first treatment choice in tertiary centres. Recent trials have demonstrated that CPAP reduces need for intubation and ventilation for infants born at 25-28 weeks gestation, and at > 32weeks, in non-tertiary hospitals, CPAP reduces need for transfer to NICU. The aim of this study was to examine recent population trends in the use of neonatal continuous positive airway pressure. Methods We undertook a population-based cohort study of all 696,816 liveborn neonates ≥24 weeks gestation in New South Wales (NSW) Australia, 2001-2008. Data were obtained from linked birth and hospitalizations records, including neonatal transfers. The primary outcome was CPAP without mechanical ventilation (via endotracheal intubation) between birth and discharge from the hospital system. Analyses were stratified by age ≤32 and > 32 weeks gestation. Results Neonates receiving any ventilatory support increased from 1,480 (17.9/1000) in 2001 to 2,486 (26.9/1000) in 2008, including 461 (5.6/1000) to 1,465 (15.8/1000) neonates who received CPAP alone. There was a concurrent decrease in mechanical ventilation use from 12.3 to 11.0/1000. The increase in CPAP use was greater among neonates > 32 weeks (from 3.2 to 11.8/1000) compared with neonates ≤32 weeks (from 18.1 to 32.7/1000). The proportion of CPAP > 32 weeks initiated in non-tertiary hospitals increased from 6% to 30%. Conclusions The use of neonatal CPAP is increasing, especially > 32 weeks gestation and among non-tertiary hospitals. Recommendations are required regarding which infants should be considered for CPAP, resources necessary for a unit to offer CPAP and monitoring of longer term outcomes. PMID:21999325

  6. Trends in highway safety: effects of an aging population on accident propensity.

    PubMed

    Stamatiadis, N; Deacon, J A

    1995-08-01

    Aging of the United States population has a potentially adverse effect on highway safety. A key question is whether the known deterioration of driving skills with aging will be compensated by other factors, especially improved learning and attitudinal experiences of more recent cohorts. We investigate effects of driver age, cohort, and gender on accident propensity and evaluate confounding effects of year, location, and lighting. The accident propensity of different groups of drivers is measured, using a database of two-vehicle accidents, by the ratio of the number of at-fault drivers of a specific group to the corresponding number of not-at-fault drivers. Logistic regression modelling determines the statistical significance of the findings. The analysis reveals the following statistically significant effects: (a) middle-aged drivers are safer than younger drivers who, in turn, are safer than older drivers; (b) female drivers are safer on average than male drivers; (c) younger female drivers are safer than younger male drivers; (d) older male drivers are safer than older female drivers; (e) more recent cohorts of older drivers are safer than more distant cohorts; and (f) more distant cohorts of younger drivers are safer than more recent cohorts. We conclude that driver cohort provides a plausible explanation for many of the measurable, time-related accident trends that are observed. Accordingly, older drivers will be safer in the future because they will have acquired basic driving skills and attitudes in increasingly more automobile-dominated times. At the same time, the cohort effect appears small relative to other time related effects, notably aging, and older drivers will continue to be a high-risk component of the driving population and to require special consideration in driver education and licensing and in highway design and operations. PMID:7546059

  7. Study on the Trend and Disease Burden of Injury Deaths in Chinese Population, 2004–2010

    PubMed Central

    Zhang, Lijuan; Li, Zhiqiang; Li, Xucheng; Zhang, Jie; Zheng, Liang; Jiang, Chenghua; Li, Jue

    2014-01-01

    Injuries are a growing public health concern in China, accounting for more than 30% of all Person Years of Life Lost (PYLL) due to premature mortality. This study analyzes the trend and disease burden of injury deaths in Chinese population from 2004 to 2010, using data from the National Disease Surveillance Points (DSPs) system, as injury deaths are classified based on the International Classification of Disease-10th Revision (ICD-10). We observed that injury death accounted for nearly 10% of all deaths in China throughout the period 2004–2010, and the injury mortality rates were higher in males than those in females, and higher in rural areas than in urban areas. Traffic crashes (33.79–38.47% of all injury deaths) and suicides (16.20–22.01%) were the two leading causes of injury deaths. Alarmingly, suicide surpassed traffic crashes as the leading cause of injury mortality in rural females, yet adults aged 65 and older suffered the greatest number of fatal falls (20,701 deaths, 2004–2010). The burden of injury among men (72.11%) was about three times more than that of women's (28.89%). This study provides indispensible evidence that China Authority needs to improve the surveillance and deterrence of three major types of injuries: Traffic-related injury deaths should be targeted for injury prevention activities in all population, people aged 65+ should be encouraged to take individual fall precautions, and prevention of suicidal behavior in rural females should be another key priority for the government of China. PMID:24465534

  8. North American Breeding Bird Survey Annual Summary, 1989

    USGS Publications Warehouse

    Droege, S.; Sauer, J.R.

    1990-01-01

    The North American Breeding Bird Survey (BBS) is run by approximately 2,000 skilled amateur ornithologists and is coordinated cooperatively by the U.S. Fish and Wildlife Service and the Canadian Wildlife Service. Since 1966, BBS cooperators have been collecting standardized information on North American bird populations. The BBS is a roadside survey, comprised of permanent routes that are surveyed yearly. Each route is 39.4 km (24.5 miles) long and consists of 50 stops spaced 0.8 km (0.5 mile) apart. All birds heard or seen during a 3-min observation period at each stop are recorded, and, for each species, the sum of the counts on individual stops is used as an index of species density on the route. Survey routes occur throughout the continental United States and most of Canada. Here, we present the population changes of the 251 bird species reported on the 50 or more BBS routes in the survey region during 1988 and 1989. Population trends for 1966-89 are presented for comparison. The direction and significance of population changes between the years for the 306 species occurring on 10 or more routes within States and Provinces are summarized in Appendix B. The pattern of population changes for selected species is graphically summarized on maps by physiographic stratum.

  9. Use of pellet-group plots to measure trends in deer and elk populations

    SciTech Connect

    Rowland, M.M.; White, G.C.; Karlen, E.M.

    1984-01-01

    Distribution and abundance of mule deer and elk were studied from 1976 to 1981 near Los Alamos, New Mexico, using pellet-group counts. Pellet-group data were shown to fit the negative binomial distribution. Counts for mule deer varied among years in all vegetation types; the population trend was generally downward. Pellet-group counts for elk (winter only) increased in ponderosa pine, but remained unchanged in other areas. Deer pellet groups were distributed similarly from year to year and were nonrandom (i.e., clumped). Elk pellet groups also were clumped, but were clumped less in mixed conifer during the latter part of the study. In ponderosa pine, where deer were most abundant, pellet groups were clumped less than in other habitats. Similarly, in mixed conifer, where elk numbers were highest, pellet groups were clumped least. Neither weather nor fire appeared to affect greatly counts of deer or elk pellet groups, although fire may have influenced distribution of elk. 37 references, 5 tables.

  10. A systematic review of psycho-oncology research in Chinese populations: emerging trends.

    PubMed

    Chambers, S K; Hyde, M K; Au, A M L; Ip, D; Shum, D; Dunn, J

    2013-11-01

    The burden of cancer in China is increasing with future psycho-oncological interventions crucial. A systematic review of psycho-oncology research in China was undertaken to assess quantity, design and target trends over time. Medline, PsycINFO, CINAHL, ProQuest, Web of Science (1999-November Week 4, 2012) were searched. Inclusion criteria were: included cancer patients and/or partners or caregivers from resident Chinese populations (either at least 80% of participants are from China, Hong Kong or Taiwan); assessed psychological adjustment relating to cancer and published in English after 1 January 1999 and prior to 30 November 2012. In all, 208 articles met inclusion criteria. Of these: 52 were cross-sectional descriptive quantitative; 30 were cross-sectional descriptive qualitative; 27 were prospective descriptive quantitative; 2 were prospective descriptive qualitative; 18 assessed interventions; 79 presented instrument validation. Publications increased eightfold from 1999 to 2012. Most studies included patients (n = 195) with 11 articles focusing on caregivers and two on patient-caregiver dyads. The most common cancer studied was breast cancer. The psycho-oncology research effort in China is dramatically increasing. A focus on culturally relevant approaches to underpin the evaluation of empirically derived interventions is warranted; as is direction of efforts to other cancers such as lung and prostate. PMID:23834328

  11. CENTRAL DARK MATTER TRENDS IN EARLY-TYPE GALAXIES FROM STRONG LENSING, DYNAMICS, AND STELLAR POPULATIONS

    SciTech Connect

    Tortora, C.; Jetzer, P.; Napolitano, N. R.; Romanowsky, A. J.

    2010-09-20

    We analyze the correlations between central dark matter (DM) content of early-type galaxies and their sizes and ages, using a sample of intermediate-redshift (z {approx} 0.2) gravitational lenses from the SLACS survey, and by comparing them to a larger sample of z {approx} 0 galaxies. We decompose the deprojected galaxy masses into DM and stellar components using combinations of strong lensing, stellar dynamics, and stellar populations modeling. For a given stellar mass, we find that for galaxies with larger sizes, the DM fraction increases and the mean DM density decreases, consistently with the cuspy halos expected in cosmological formation scenarios. The DM fraction also decreases with stellar age, which can be partially explained by the inverse correlation between size and age. The residual trend may point to systematic dependencies on formation epoch of halo contraction or stellar initial mass functions. These results are in agreement with recent findings based on local galaxies by Napolitano et al. and suggest negligible evidence of galaxy evolution over the last {approx}2.5 Gyr other than passive stellar aging.

  12. Top-down and bottom-up factors affecting seabird population trends in the California current system (1985-2006)

    NASA Astrophysics Data System (ADS)

    Ainley, David G.; David Hyrenbach, K.

    2010-03-01

    To characterize the environmental factors affecting seabird population trends in the central portion of the California current system (CCS), we analyzed standardized vessel-based surveys collected during the late spring (May-June) upwelling season over 22 yr (1985-2006). We tested the working hypothesis that population trends are related to species-specific foraging ecology, and predicted that temporal variation in population size should be most extreme in diving species with higher energy expenditure during foraging. We related variation in individual species abundance (number km -2) to seasonally lagged (late winter, early spring, late spring) and concurrent ocean conditions, and to long-term trends (using a proxy variable: year) during a multi-decadal period of major fluctuations in the El Niño-Southern oscillation (ENSO) and the Pacific decadal oscillation (PDO). We considered both remote (Multivariate ENSO Index, PDO) and local (coastal upwelling indices and sea-surface temperature) environmental variables as proxies for ocean productivity and prey availability. We also related seabird trends to those of potentially major trophic competitors, humpback ( Megaptera novaeangliae) and blue ( Balaenoptera musculus) whales, which increased in number 4-5-fold midway during our study. Cyclical oscillations in seabird abundance were apparent in the black-footed albatross ( Phoebastria nigripes), and decreasing trends were documented for ashy storm-petrel ( Oceanodroma homochroa), pigeon guillemot ( Cepphus columbus), rhinoceros auklet ( Cerorhinca monocerata), Cassin’s auklet ( Ptychoramphus aleuticus), and western gull ( Larus occidentalis); the sooty shearwater ( Puffinus griseus), exhibited a marked decline before signs of recovery at the end of the study period. The abundance of nine other focal species varied with ocean conditions, but without decadal or long-term trends. Six of these species have the largest global populations in the CCS, and four are highly

  13. Trends in heat-related mortality in urban populations of the Czech Republic over 1994-2013

    NASA Astrophysics Data System (ADS)

    Urban, Aleš; Kyselý, Jan

    2016-04-01

    The study resumes previous research that found significant effects of hot spells on increased mortality in highly urbanized regions of the Czech Republic, and declining trends in heat-related mortality in the Czech population as a whole. We analyze severe hot spells during 1994-2013 and temporal changes of their effects on total and cardiovascular mortality in several urban regions with a different overall socioeconomic level (city of Prague, city of Brno, Ostrava region, NW Bohemia). Mortality data were standardized to account for different population structure and its changes over time. The mortality baseline for each region was determined using a generalized additive model. Although declining trends in the mortality impacts of hot spells prevail in most regions in spite of rising temperature trends, the magnitude of the mortality decline was different with respect to the overall socioeconomic level and development of the regions. The results suggest that trends in heat-related mortality depend on the level of socioeconomic deprivation of population. It is essential to better understand the risks of climate change in different parts of population with respect to their adaptability.

  14. Trends and Milestones: Continuing Reduction in Populations of Large State Residential Facilities for Persons with Intellectual and Developmental Disabilities.

    ERIC Educational Resources Information Center

    Coucouvanis, Kathie; Polister, Barbara; Prouty, Robert; Lakin, K. Charlie

    2003-01-01

    This article discusses the continuing trend of downsizing and closure of large state institutions for persons with mental retardation. Between 1987 and 2001, nine states closed all of their large state residential facilities, reducing the total national population of such facilities by 2,414 residents. A chart illustrates state reductions. (CR)

  15. Rate and Time Trend of Perinatal, Infant, Maternal Mortality, Natality and Natural Population Growth in Kosovo

    PubMed Central

    Azemi, Mehmedali; Gashi, Sanije; Berisha, Majlinda; Kolgeci, Selim; Ismaili-Jaha, Vlora

    2012-01-01

    Aim: The aim of work has been the presentation of the rate and time trends of some indicators of the heath condition of mothers and children in Kosovo: fetal mortality, early neonatal mortality, perinatal mortality, infant mortality, natality, natural growth of population etc. The treated patients were the newborn and infants in the post neonatal period, women during their pregnancy and those 42 days before and after the delivery. Methods: The data were taken from: register of the patients treated in the Pediatric Clinic of Prishtina, World Health Organization, Mother and Child Health Care, Reproductive Health Care, Ministry of Health of the Republic of Kosovo, Statistical Department of Kosovo, the National Institute of Public Health and several academic texts in the field of pediatrics. Some indicators were analyzed in a period between year 1945-2010 and 1950-2010, whereas some others were analyzed in a time period between year 2000 and 2011. Results: The perinatal mortality rate in 2000 was 29.1‰, whereas in 2011 it was 18.7‰. The fetal mortality rate was 14.5‰ during the year 2000, whereas in 2011 it was 11.0‰, in 2000 the early neonatal mortality was 14.8‰, in 2011 it was 7.5‰. The infant mortality in Kosovo was 164‰ in 1950, whereas in 2010 it was 20.5‰. The most frequent causes of infant mortality have been: lower respiratory tract infections, acute infective diarrhea, perinatal causes, congenital malformations and unclassified conditions. Maternal death rate varied during this time period. Maternal death in 2000 was 23 whereas in 2010 only two cases were reported. Regarding the natality, in 1950 it reached 46.1 ‰, whereas in 2010 it reached 14‰, natural growth of population rate in Kosovo was 29.1‰ in 1950, whereas in 2011 it was 11.0‰. Conclusion: Perinatal mortality rate in Kosovo is still high in comparison with other European countries (Turkey and Kyrgyzstan have the highest perinatal mortality rate), even though it is in a

  16. Population signatures of large-scale, long-term disjunction and small-scale, short-term habitat fragmentation in an Afromontane forest bird.

    PubMed

    Habel, J C; Mulwa, R K; Gassert, F; Rödder, D; Ulrich, W; Borghesio, L; Husemann, M; Lens, L

    2014-09-01

    The Eastern Afromontane cloud forests occur as geographically distinct mountain exclaves. The conditions of these forests range from large to small and from fairly intact to strongly degraded. For this study, we sampled individuals of the forest bird species, the Montane White-eye Zosterops poliogaster from 16 sites and four mountain archipelagos. We analysed 12 polymorphic microsatellites and three phenotypic traits, and calculated Species Distribution Models (SDMs) to project past distributions and predict potential future range shifts under a scenario of climate warming. We found well-supported genetic and morphologic clusters corresponding to the mountain ranges where populations were sampled, with 43% of all alleles being restricted to single mountains. Our data suggest that large-scale and long-term geographic isolation on mountain islands caused genetically and morphologically distinct population clusters in Z. poliogaster. However, major genetic and biometric splits were not correlated to the geographic distances among populations. This heterogeneous pattern can be explained by past climatic shifts, as highlighted by our SDM projections. Anthropogenically fragmented populations showed lower genetic diversity and a lower mean body mass, possibly in response to suboptimal habitat conditions. On the basis of these findings and the results from our SDM analysis we predict further loss of genotypic and phenotypic uniqueness in the wake of climate change, due to the contraction of the species' climatic niche and subsequent decline in population size. PMID:24713824

  17. Population signatures of large-scale, long-term disjunction and small-scale, short-term habitat fragmentation in an Afromontane forest bird

    PubMed Central

    Habel, J C; Mulwa, R K; Gassert, F; Rödder, D; Ulrich, W; Borghesio, L; Husemann, M; Lens, L

    2014-01-01

    The Eastern Afromontane cloud forests occur as geographically distinct mountain exclaves. The conditions of these forests range from large to small and from fairly intact to strongly degraded. For this study, we sampled individuals of the forest bird species, the Montane White-eye Zosterops poliogaster from 16 sites and four mountain archipelagos. We analysed 12 polymorphic microsatellites and three phenotypic traits, and calculated Species Distribution Models (SDMs) to project past distributions and predict potential future range shifts under a scenario of climate warming. We found well-supported genetic and morphologic clusters corresponding to the mountain ranges where populations were sampled, with 43% of all alleles being restricted to single mountains. Our data suggest that large-scale and long-term geographic isolation on mountain islands caused genetically and morphologically distinct population clusters in Z. poliogaster. However, major genetic and biometric splits were not correlated to the geographic distances among populations. This heterogeneous pattern can be explained by past climatic shifts, as highlighted by our SDM projections. Anthropogenically fragmented populations showed lower genetic diversity and a lower mean body mass, possibly in response to suboptimal habitat conditions. On the basis of these findings and the results from our SDM analysis we predict further loss of genotypic and phenotypic uniqueness in the wake of climate change, due to the contraction of the species' climatic niche and subsequent decline in population size. PMID:24713824

  18. Bird guard

    DOEpatents

    Fairchild, Dana M.

    2010-03-02

    The bird guard provides a device to protect electrical insulators comprising a central shaft; a clamp attached to an end of the shaft to secure the device to a transmission tower; a top and bottom cover to shield transmission tower insulators; and bearings to allow the guard to rotate in order to frighten birds away from the insulators.

  19. Biology and Conservation of the Common Murre in California, Oregon, Washington, and British Columbia: Vol. 1, Natural History and Population Trends

    USGS Publications Warehouse

    Manuwal, David Allen, (Edited By); Carter, Harry R.; Zimmerman, Tara S.; Orthmeyer, Dennis L.

    2001-01-01

    EXECUTIVE SUMMARY Over the past 30 years, the common murre (Uria aalge californica) has been recognized as a prominent indicator of marine conservation issues in California, Oregon, Washington, and British Columbia, especially regarding oil pollution, certain fisheries, and human disturbance. To assist the effective management of the common murre and the marine environments in which they live, this summary of available information on the biology and regional status of the common murre has been sponsored by the U.S. Fish and Wildlife Service (Division of Migratory Bird Management). In Volume 1 (Chapter 1), the natural history of the common murre is summarized, drawing heavily on breeding studies from the South Farallon Islands, California, plus a host of detailed breeding studies from the North Atlantic Ocean. Population trends of the common murre are summarized in Volume 1 (Chapter 2), focusing on changes in whole-colony counts determined from aerial photographs between the late 1970s and 1995 in California, Oregon and Washington. Historical data and human impacts to murre colonies since the early nineteenth century are also summarized. Volume 2 will summarize population threats, conservation, and management. Information presented in Volume 1 has been obtained and recorded by a large number of researchers and natural historians over two centuries. From the 1960s to 1995, most work in California, Oregon, and Washington was sponsored by the U.S. Fish and Wildlife Service, Minerals Management Service, and California Department of Fish and Game. Important breeding biology studies were conducted at the South Farallon Islands (Farallon National Wildlife Refuge) by the Point Reyes Bird Observatory, in coordination with the U.S. Fish and Wildlife Service (San Francisco Bay National Wildlife Refuge). Colony surveys in California were conducted mainly by the U.S. Fish and Wildlife Service (San Francisco Bay National Wildlife Refuge), U.S. Geological Survey (Western

  20. Coordinating across scales: Building a regional marsh bird monitoring program from national and state Initiatives

    USGS Publications Warehouse

    Shriver, G.W.; Sauer, J.R.

    2008-01-01

    Salt marsh breeding bird populations (rails, bitterns, sparrows, etc.) in eastern North America are high conservation priorities in need of site specific and regional monitoring designed to detect population changes over time. The present status and trends of these species are unknown but anecdotal evidence of declines in many of the species has raised conservation concerns. Most of these species are listed as conservation priorities on comprehensive wildlife plans throughout the eastern U.S. National Wildlife Refuges, National Park Service units, and other wildlife conservation areas provide important salt marsh habitat. To meet management needs for these areas, and to assist regional conservation planning, survey designs are being developed to estimate abundance and population trends for these breeding bird species. The primary purpose of this project is to develop a hierarchical sampling frame for salt marsh birds in Bird Conservation Region (BCR) 30 that will provide the ability to estimate species population abundances on 1) specific sites (i.e. National Parks and National Wildlife Refuges), 2) within states or regions, and 3) within BCR 30. The entire breeding range of Saltmarsh Sharp-tailed and Coastal Plain Swamp sparrows are within BCR 30, providing an opportunity to detect population trends within the entire breeding ranges of two priority species.

  1. Estimating temporal trend in the presence of spatial complexity: A Bayesian hierarchical model for a wetland plant population undergoing restoration

    USGS Publications Warehouse

    Rodhouse, T.J.; Irvine, K.M.; Vierling, K.T.; Vierling, L.A.

    2011-01-01

    Monitoring programs that evaluate restoration and inform adaptive management are important for addressing environmental degradation. These efforts may be well served by spatially explicit hierarchical approaches to modeling because of unavoidable spatial structure inherited from past land use patterns and other factors. We developed Bayesian hierarchical models to estimate trends from annual density counts observed in a spatially structured wetland forb (Camassia quamash [camas]) population following the cessation of grazing and mowing on the study area, and in a separate reference population of camas. The restoration site was bisected by roads and drainage ditches, resulting in distinct subpopulations ("zones") with different land use histories. We modeled this spatial structure by fitting zone-specific intercepts and slopes. We allowed spatial covariance parameters in the model to vary by zone, as in stratified kriging, accommodating anisotropy and improving computation and biological interpretation. Trend estimates provided evidence of a positive effect of passive restoration, and the strength of evidence was influenced by the amount of spatial structure in the model. Allowing trends to vary among zones and accounting for topographic heterogeneity increased precision of trend estimates. Accounting for spatial autocorrelation shifted parameter coefficients in ways that varied among zones depending on strength of statistical shrinkage, autocorrelation and topographic heterogeneity-a phenomenon not widely described. Spatially explicit estimates of trend from hierarchical models will generally be more useful to land managers than pooled regional estimates and provide more realistic assessments of uncertainty. The ability to grapple with historical contingency is an appealing benefit of this approach.

  2. Patterns and trends of pancreatic cancer mortality rates in Arkansas, 1969-2002: a comparison with the US population.

    PubMed

    Zhang, Jianjun; Dhakal, Ishwori; Ning, Baitang; Kesteloot, Hugo

    2008-02-01

    Little is known about trends in pancreatic cancer mortality in individual states of the US and its whole population. This study aimed to describe the patterns and trends of pancreatic cancer mortality in Arkansas, 1969-2002, using the US national rates as a reference. Joinpoint regression analyses were performed to evaluate trends in age-standardized mortality rates of pancreatic cancer by age group, sex, and race, using data obtained from the National Center for Health Statistics. Throughout the period examined, mortality decreased in young and middle-aged people (<60 years) and men but increased in old people (>/=60 years) and women. A continuous fall in mortality occurred among whites except for a transient rise in the late 1970s. For blacks, mortality rates did not cease to increase until 1995. Unlike in Arkansas, a monotonic upward or downward trend in mortality by age group and sex was not observed in the US. A decline of mortality stopped in 1997 for US whites. Recent decreasing trends were more pronounced in Arkansas blacks than in US blacks. Changes of pancreatic cancer mortality in the last three decades in Arkansas remarkably differed by age, sex, and race and were different in patterns from those of the US population. PMID:18090906

  3. Estimating temporal trend in the presence of spatial complexity: a Bayesian hierarchical model for a wetland plant population undergoing restoration.

    PubMed

    Rodhouse, Thomas J; Irvine, Kathryn M; Vierling, Kerri T; Vierling, Lee A

    2011-01-01

    Monitoring programs that evaluate restoration and inform adaptive management are important for addressing environmental degradation. These efforts may be well served by spatially explicit hierarchical approaches to modeling because of unavoidable spatial structure inherited from past land use patterns and other factors. We developed bayesian hierarchical models to estimate trends from annual density counts observed in a spatially structured wetland forb (Camassia quamash [camas]) population following the cessation of grazing and mowing on the study area, and in a separate reference population of camas. The restoration site was bisected by roads and drainage ditches, resulting in distinct subpopulations ("zones") with different land use histories. We modeled this spatial structure by fitting zone-specific intercepts and slopes. We allowed spatial covariance parameters in the model to vary by zone, as in stratified kriging, accommodating anisotropy and improving computation and biological interpretation. Trend estimates provided evidence of a positive effect of passive restoration, and the strength of evidence was influenced by the amount of spatial structure in the model. Allowing trends to vary among zones and accounting for topographic heterogeneity increased precision of trend estimates. Accounting for spatial autocorrelation shifted parameter coefficients in ways that varied among zones depending on strength of statistical shrinkage, autocorrelation and topographic heterogeneity--a phenomenon not widely described. Spatially explicit estimates of trend from hierarchical models will generally be more useful to land managers than pooled regional estimates and provide more realistic assessments of uncertainty. The ability to grapple with historical contingency is an appealing benefit of this approach. PMID:22163047

  4. Electrical burns: The trend and risk factors in the Ghanaian population

    PubMed Central

    Agbenorku, P.; Agbenorku, E.; Akpaloo, J.; Obeng, G.; Agbley, D.

    2014-01-01

    Summary The usefulness of electricity in daily life offers several advantages which cannot be underestimated. Electricity is needed by industries for manufacturing and also in homes for lighting, cooking, washing, etc. However, electricity can cause severe life-threatening complications. This study investigates the trend and mortality risk factors of electrical burn injuries at the Burns Intensive Care Unit (BICU) of the Komfo Anokye Teaching Hospital (KATH), Ghana. The Burns Registry at KATH BICU containing information on patients who were admitted for electrical burns was used. Data on the sex, age, occupation, cause of injury, Total Body Surface Area burned (TBSA) and outcome of admissions was obtained. GraphPad version 5 was used for the analysis. There were 13 (2.7%) electrical burns, suffered by 11 males (84.6%) and 2 females (15.4%) out of a total 487 BICU admissions over a 4-year period (July 1, 2009 – June 30, 2013); the mean age of the electrical burn victims was 37.8 years (range = 22–56); the TBSA ranged from 5.0% - 98.0%. Mortality risk factors identified were high voltage electrical burns, older age (P=0.0250) and TBSA>20% (P=0.048). Four cases (30.8%) were transferred to the Main Burns Ward (Ward D2C); 6 cases (46.1%) were discharged home; 3 patients (23.1%) died; all deaths were recorded in persons who had high voltage electrical burns. Electrical burns can be severe and can cause death. Even though the current study showed that a small population was affected by electrical burns, society has to be continually conscious of the detrimental effects of electrical energy and take the necessary precautions to minimize this type of accident. PMID:26336364

  5. Temporal Trends in the Incidence and Natural History of Diverticulitis: A Population-Based Study

    PubMed Central

    Bharucha, Adil E.; Parthasarathy, Gopanandan; Ditah, Ivo; Fletcher, J. G.; Ewelukwa, Ofor; Pendlimari, Rajesh; Yawn, Barbara P.; Melton, L. Joseph; Schleck, Cathy; Zinsmeister, Alan R.

    2015-01-01

    Background & Aims Data on the incidence and natural history of diverticulitis are largely hospital-based and exclude the majority of diverticulitis patients, who are treated in an outpatient setting for uncomplicated diverticulitis. We assessed temporal trends in the epidemiology of diverticulitis in the general population. Methods Through the Rochester Epidemiology Project we reviewed the records of all individuals with a diagnosis of diverticulitis from 1980–2007 in Olmsted County, Minnesota. Results In 1980–1989 the incidence of diverticulitis was 115/100,000 person-years, which increased to 188/100,000 in 2000–2007 (P<.001). Incidence increased with age (P<.001); however, the temporal increase was greater in younger people (P<.001). Ten years after the index and second diverticulitis episodes, 22% and 55% had a recurrence, respectively. This recurrence rate was greater in younger people (hazard ratio [HR] per decade 0.63; 95% confidence interval [CI], 0.59–0.66) and women (HR 0.68; 95% CI, 0.58–0.80). Complications were seen in 12%; this rate did not change over time. Recurrent diverticulitis was associated with a decreased risk of complications (P<.001). Age was associated with increased risk of local (odds ratio [OR] 1.27 per decade; 95% CI, 1.04–1.57) and systemic (OR 1.83; 95% CI, 1.20–2.80) complications. Survival after diverticulitis was lower in older people (P<.001) and men (P<.001) and worsened over time (P<.001). The incidence of surgery for diverticulitis did not change from 1980–2007. Conclusions The incidence of diverticulitis has increased by 50% in 2000–2007 compared to 1990–1999, and more so in younger people. Complications are relatively uncommon. Recurrent diverticulitis is frequent but typically uncomplicated. Younger people with diverticulitis had less severe disease, more recurrence, and better survival. PMID:26416187

  6. Trends in the Incidence of Parkinson Disease in the General Population: The Rotterdam Study.

    PubMed

    Darweesh, Sirwan K L; Koudstaal, Peter J; Stricker, Bruno H; Hofman, Albert; Ikram, M Arfan

    2016-06-01

    We investigated trends in the incidence of parkinsonism and Parkinson disease (PD) by comparing data from the first 2 subcohorts of the Rotterdam Study, a prospective, population-based cohort study (first subcohort: baseline 1990 with 10 years of follow-up; second subcohort, baseline 2000 with 10 years of follow-up). From the baseline years, we observed differences in the second subcohort that were associated with a lower risk of PD for some but not all baseline risk factors. Participants in both subcohorts were followed for a maximum of 10 years and monitored for the onset of parkinsonism, the onset of dementia, or death, until January 1, 2011. We used Poisson regression models to compare the incidences of parkinsonism, both overall and by cause (PD and secondary causes), and competitive events (incident dementia and death) as well as the mortality of parkinsonism patients in the 2 subcohorts. In the 1990 subcohort, there were 182 cases of parkinsonism (84 of which were PD) during 57,052 person-years. In the 2000 subcohort, we observed 28 cases of parkinsonism (10 with PD) during 22,307 person-years. The overall age- and sex-adjusted incidence of parkinsonism was lower in the 2000 subcohort (incidence rate ratio = 0.55, 95% confidence interval: 0.36, 0.81), and PD incidence declined sharply (incidence rate ratio = 0.39, 95% confidence interval: 0.19, 0.72). Competitive event rates were lower in the 2000 subcohort, and mortality rates among persons with parkinsonism remained stable. These findings suggest that the incidence of parkinsonism in general, and of PD in particular, decreased between 1990 and 2011. PMID:27188952

  7. Trends in the incidence of cancer in the black population of Harare, Zimbabwe 1991-2010.

    PubMed

    Chokunonga, E; Borok, M Z; Chirenje, Z M; Nyakabau, A M; Parkin, D M

    2013-08-01

    Incidence rates of different cancers have been calculated for the black population of Harare, Zimbabwe for a 20-year period (1991-2010) coinciding with continuing social and lifestyle changes, and the peak, and subsequent wane, of the HIV-AIDS epidemic. The overall risk of cancer increased during the period in both sexes, with rates of cervix and prostate cancers showing particularly dramatic increases (3.3% and 6.4% annually, respectively). By 2004, prostate cancer had become the most common cancer of men. The incidence of cancer of the esophagus, formerly the most common cancer of men, has remained relatively constant, whereas rates of breast and cervix cancers, the most common malignancies of women, have shown significant increases (4.9% and 3.3% annually, respectively). The incidence of Kaposi sarcoma increased to a maximum around 1998-2000 and then declined in all age groups, and in both sexes The incidence of squamous cell cancers of the conjunctiva is relatively high, with temporal trends similar to those of Kaposi sarcoma. Non-Hodgkin lymphoma, the fifth most common cancer of men and fourth of women, showed a steady increase in incidence throughout the period (6.7-6.9% annually), although rates in young adults (15-39) have decreased since 2001. Cancer control in Zimbabwe, as elsewhere in sub-Saharan Africa, involves meeting the challenge of emerging cancers associated with westernization of lifestyles (large bowel, breast and prostate), while the incidence of cancers associated with poverty and infection (liver, cervix and esophagus) shows little decline, and the residual burden of the AIDS-associated cancers remains significant. PMID:23364833

  8. Population trends in Pacific Oceanic sharks and the utility of regulations on shark finning.

    PubMed

    Clarke, Shelley C; Harley, Shelton J; Hoyle, Simon D; Rice, Joel S

    2013-02-01

    Accurate assessment of shark population status is essential for conservation but is often constrained by limited and unreliable data. To provide a basis for improved management of shark resources, we analyzed a long-term record of species-specific catches, sizes, and sexes of sharks collected by onboard observers in the western and central Pacific Ocean from 1995 to 2010. Using generalized linear models, we estimated population-status indicators on the basis of catch rate and biological indicators of fishing pressure on the basis of median size to identify trends for blue (Prionace glauca), mako (Isurus spp.), oceanic whitetip (Carcharhinus longimanus), and silky (Carcharhinus falciformis) sharks. Standardized catch rates of longline fleets declined significantly for blue sharks in the North Pacific (by 5% per year [CI 2% to 8%]), for mako sharks in the North Pacific (by 7% per year [CI 3% to 11%]), and for oceanic whitetip sharks in tropical waters (by 17% per year [CI 14% to 20%]). Median lengths of silky and oceanic whitetip sharks decreased significantly in their core habitat, and almost all sampled silky sharks were immature. Our results are consistent with results of analyses of similar data sets. Combined, these results and evidence of targeted fishing for sharks in some regional fisheries heighten concerns for sustainable utilization, particularly for oceanic whitetip and North Pacific blue sharks. Regional regulations that prohibit shark finning (removal of fins and discarding of the carcass) were enacted in 2007 and are in many cases the only form of control on shark catches. However, there is little evidence of a reduction of finning in longline fisheries. In addition, silky and oceanic whitetip sharks are more frequently retained than finned, which suggests that even full implementation of and adherence to a finning prohibition may not substantially reduce mortality rates for these species. We argue that finning prohibitions divert attention from

  9. Massive Nest-Box Supplementation Boosts Fecundity, Survival and Even Immigration without Altering Mating and Reproductive Behaviour in a Rapidly Recovered Bird Population

    PubMed Central

    Berthier, Karine; Leippert, Fabio; Fumagalli, Luca; Arlettaz, Raphaël

    2012-01-01

    Habitat restoration measures may result in artificially high breeding density, for instance when nest-boxes saturate the environment, which can negatively impact species' demography. Potential risks include changes in mating and reproductive behaviour such as increased extra-pair paternity, conspecific brood parasitism, and polygyny. Under particular cicumstances, these mechanisms may disrupt reproduction, with populations dragged into an extinction vortex. With the use of nuclear microsatellite markers, we investigated the occurrence of these potentially negative effects in a recovered population of a rare secondary cavity-nesting farmland bird of Central Europe, the hoopoe (Upupa epops). High intensity farming in the study area has resulted in a total eradication of cavity trees, depriving hoopoes from breeding sites. An intensive nest-box campaign rectified this problem, resulting in a spectacular population recovery within a few years only. There was some concern, however, that the new, high artificially-induced breeding density might alter hoopoe mating and reproductive behaviour. As the species underwent a serious demographic bottleneck in the 1970–1990s, we also used the microsatellite markers to reconstitute the demo-genetic history of the population, looking in particular for signs of genetic erosion. We found i) a low occurrence of extra-pair paternity, polygyny and conspecific brood parasitism, ii) a high level of neutral genetic diversity (mean number of alleles and expected heterozygosity per locus: 13.8 and 83%, respectively) and, iii) evidence for genetic connectivity through recent immigration of individuals from well differentiated populations. The recent increase in breeding density did thus not induce so far any noticeable detrimental changes in mating and reproductive behaviour. The demographic bottleneck undergone by the population in the 1970s-1990s was furthermore not accompanied by any significant drop in neutral genetic diversity. Finally

  10. Analyzing NEXRAD doppler radar images to assess nightly dispersal patterns and population trends in Brazilian free-tailed bats (Tadarida brasiliensis).

    PubMed

    Horn, Jason W; Kunz, Thomas H

    2008-07-01

    Operators of early weather-surveillance radars often observed echoes on their displays that did not behave like weather pattern, including expanding ring-like shapes they called angels. These echoes were caused by high-flying insects, migrating birds, and large colonies of bats emerging from roosts to feed. Modern weather-surveillance radar stations in the United States (NEXt-generation RADar or NEXRAD) provide detailed images that clearly show evening bat emergences from large colonies. These images can be used to investigate the flight behavior of groups of bats and population trends in large colonies of Brazilian free-tailed bats (Tadarida brasiliensis) in south-central Texas which are clearly imaged by local NEXRAD radar stations. In this study, we used radar reflectivity data from the New Braunfels, Texas NEXRAD station to examine relative colony size, direction of movement, speed of dispersion, and altitude gradients of bats from these colonies following evening emergence. Base reflectivity clear-air-mode Level-II images were geo-referenced and compiled in a GIS along with locations of colonies and features on the landscape. Temporal sequences of images were filtered for the activity of bats, and from this, the relative size of bat colonies, and the speed and heading of bat emergences were calculated. Our results indicate cyclical changes in colony size from year to year and that initial headings taken by bats during emergence flights are highly directional. We found that NEXRAD data can be an effective tool for monitoring the nightly behavior and seasonal changes in these large colonies. Understanding the distribution of a large regional bat population on a landscape scale has important implications for agricultural pest management and conservation efforts. PMID:21669770

  11. Threatened bird valuation in Australia.

    PubMed

    Zander, Kerstin K; Ainsworth, Gillian B; Meyerhoff, Jürgen; Garnett, Stephen T

    2014-01-01

    Threatened species programs need a social license to justify public funding. A contingent valuation survey of a broadly representative sample of the Australian public found that almost two thirds (63%) supported funding of threatened bird conservation. These included 45% of a sample of 645 respondents willing to pay into a fund for threatened bird conservation, 3% who already supported bird conservation in another form, and 15% who could not afford to pay into a conservation fund but who nevertheless thought that humans have a moral obligation to protect threatened birds. Only 6% explicitly opposed such payments. Respondents were willing to pay about AUD 11 annually into a conservation fund (median value), including those who would pay nothing. Highest values were offered by young or middle aged men, and those with knowledge of birds and those with an emotional response to encountering an endangered bird. However, the prospect of a bird going extinct alarmed almost everybody, even most of those inclined to put the interests of people ahead of birds and those who resent the way threatened species sometimes hold up development. The results suggest that funding for threatened birds has widespread popular support among the Australian population. Conservatively they would be willing to pay about AUD 14 million per year, and realistically about AUD 70 million, which is substantially more than the AUD 10 million currently thought to be required to prevent Australian bird extinctions. PMID:24955957

  12. Threatened Bird Valuation in Australia

    PubMed Central

    Zander, Kerstin K.; Ainsworth, Gillian B.; Meyerhoff, Jürgen; Garnett, Stephen T.

    2014-01-01

    Threatened species programs need a social license to justify public funding. A contingent valuation survey of a broadly representative sample of the Australian public found that almost two thirds (63%) supported funding of threatened bird conservation. These included 45% of a sample of 645 respondents willing to pay into a fund for threatened bird conservation, 3% who already supported bird conservation in another form, and 15% who could not afford to pay into a conservation fund but who nevertheless thought that humans have a moral obligation to protect threatened birds. Only 6% explicitly opposed such payments. Respondents were willing to pay about AUD 11 annually into a conservation fund (median value), including those who would pay nothing. Highest values were offered by young or middle aged men, and those with knowledge of birds and those with an emotional response to encountering an endangered bird. However, the prospect of a bird going extinct alarmed almost everybody, even most of those inclined to put the interests of people ahead of birds and those who resent the way threatened species sometimes hold up development. The results suggest that funding for threatened birds has widespread popular support among the Australian population. Conservatively they would be willing to pay about AUD 14 million per year, and realistically about AUD 70 million, which is substantially more than the AUD 10 million currently thought to be required to prevent Australian bird extinctions. PMID:24955957

  13. Epidemiologic characterization of Colorado backyard bird flocks.

    PubMed

    Smith, Emily I; Reif, John S; Hill, Ashley E; Slota, Katharine E; Miller, Ryan S; Bjork, Kathe E; Pabilonia, Kristy L

    2012-06-01

    Backyard gallinaceous bird flocks may play an important role in the spread of infectious diseases within poultry populations as well as the transmission of zoonotic diseases to humans. An epidemiologic characterization was conducted of Colorado backyard flocks to gather information on general flock characteristics, human movement of birds, human-bird interaction, biosecurity practices, and flock health. Our results suggest that backyard poultry flocks in Colorado are small-sized flocks (68.6% of flocks had < 50 birds); consist primarily of layer chickens (85.49% of flocks), show chickens (32.18% of flocks), and waterfowl (34.07% of flocks); and are primarily owned for food (meat or egg) production for the family (86.44%) or as pet or hobby birds (42.27%). The backyard flock environment may promote bird-to-bird transmission as well as bird-to-human transmission of infectious disease. Birds are primarily housed with free access to the outside (96.85%), and many are moved from the home premises (46.06% within 1 yr). Human contact with backyard flocks is high, biosecurity practices are minimal, and bird health is negatively impacted by increased movement events. Increased knowledge of backyard bird characteristics and associated management practices can provide guidelines for the development of measures to decrease disease transmission between bird populations, decrease disease transmission from birds to humans, and increase the overall health of backyard birds. PMID:22856180

  14. Model-Based Predictions of the Effects of Harvest Mortality on Population Size and Trend of Yellow-Billed Loons

    USGS Publications Warehouse

    Schmutz, Joel A.

    2009-01-01

    Yellow-billed loons (Gavia adamsii) breed in low densities in northern tundra habitats in Alaska, Canada, and Russia. They migrate to coastal marine habitats at mid to high latitudes where they spend their winters. Harvest may occur throughout the annual cycle, but of particular concern are recent reports of harvest from the Bering Strait region, which lies between Alaska and Russia and is an area used by yellow-billed loons during migration. Annual harvest for this region was reported to be 317, 45, and 1,077 during 2004, 2005, and 2007, respectively. I developed a population model to assess the effect of this reported harvest on population size and trend of yellow-billed loons. Because of the uncertainty regarding actual harvest and definition of the breeding population(s) affected by this harvest, I considered 25 different scenarios. Predicted trends across these 25 scenarios ranged from stability to rapid decline (24 percent per year) with halving of the population in 3 years. Through an assessment of literature and unpublished satellite tracking data, I suggest that the most likely of these 25 scenarios is one where the migrant population subjected to harvest in the Bering Strait includes individuals from breeding populations in Alaska (Arctic coastal plain and the Kotzebue region) and eastern Russia, and for which the magnitude of harvest varies among years and emulates the annual variation of reported harvest during 2004-07 (317, 45, and 1,077 yellow-billed loons). This scenario, which assumes no movement of Canadian breeders through the Bering Strait, predicts a 4.6 percent rate of annual population decline, which would halve the populations in 15 years. Although these model outputs reflect the best available information, confidence in these predictions and applicable scenarios would be greatly enhanced by more information on harvest, rates of survival and reproduction, and migratory pathways.

  15. Analysis of the North American Breeding Bird Survey using hierarchical models

    USGS Publications Warehouse

    Sauer, John R.; Link, William A.

    2011-01-01

    We analyzed population change for 420 bird species from the North American Breeding Bird Survey (BBS) using a hierarchical log-linear model, and compared the results to route regression analysis results. Survey-wide trend estimates based on the hierarchical model were more precise than estimates from the earlier analysis. No consistent pattern of differences existed in magnitude of trends between the analysis methods. Survey-wide trend estimates changed substantially for 15 species between route regression and hierarchical model analyses. We compared regional estimates for states, provinces, and Bird Conservation Regions; differences observed in these regional analyses are likely a consequence of the route regression procedure's inadequate accommodation of temporal differences in survey effort. We used species-specific hierarchical model results to estimate composite change for groups of birds associated with major habitats and migration types. Grassland, aridland, and eastern forest obligate bird species declined, while urban/suburban species increased over the interval 1968-2008. No migration status group experienced significant changes, although Nearctic-Neotropical migrant species showed intervals of decline and permanent resident species increased almost 20% during the interval. Hierarchical model results better portrayed patterns of population change over time than route regression results; we recommend use of hierarchical models for BBS analyses.

  16. Analysis of the North American Breeding Bird Survey using hierarchical models

    USGS Publications Warehouse

    Sauer, J.R.; Link, W.A.

    2011-01-01

    We analyzed population change for 420 bird species from the North American Breeding Bird Survey (BBS) using a hierarchical log-linear model and compared the results with those obtained through route-regression analysis. Survey-wide trend estimates based on the hierarchical model were generally more precise than estimates from the earlier analysis. No consistent pattern of differences existed in the magnitude of trends between the analysis methods. Survey-wide trend estimates changed substantially for 15 species between route-regression and hierarchical-model analyses. We compared regional estimates for states, provinces, and Bird Conservation Regions; differences observed in these regional analyses are likely a consequence of the route-regression procedure's inadequate accommodation of temporal differences in survey effort. We used species-specific hierarchical-model results to estimate composite change for groups of birds associated with major habitats and migration types. Grassland, aridland, and eastern-forestobligate bird species declined, whereas urban-suburban species increased over the interval 1968-2008. No migration status group experienced significant changes, although Nearctic-Neotropical migrant species showed intervals of decline and permanent resident species increased almost 20% during the interval. Hierarchical-model results better portrayed patterns of population change over time than route-regression results. We recommend use of hierarchical models for BBS analyses. ?? The American Ornithologists' Union, 2011.

  17. Cancer incidence, trends, and survival among immigrants to Sweden: a population-based study.

    PubMed

    Mousavi, Seyed Mohsen; Hemminki, Kari

    2015-03-01

    This review aimed at covering cancer risk trends by site and histology in first-generation and second-generation immigrants in Sweden compared with natives. In addition, we reviewed data on cancer survival in immigrants to explore factors explaining cancer survival in the entire population. The Swedish Family-Cancer Database was used to calculate standardized incidence ratios and hazard ratios (HRs) of death from cancer in 77,360 and 993,824 cases among first-generation, and 4356 and 263,485 cases among second-generation immigrants and Swedes, respectively. Ordinal logistic regression analyses were used to calculate odds ratio. To obtain the maximum number of cases, we classified the immigrants according to geographical setting, population, and/or cancer risk. Compared with native Swedes, the highest risk of cancer was observed for nasopharyngeal carcinoma in Southeast Asian men (standardized incidence ratio=35.6) and women (24.6), for hypopharyngeal carcinoma in Indian men (5.4), for squamous-cell carcinoma of the esophagus in Iranian women (3.8), for cardia of the stomach in East Asian women (4.2), for signet-ring cell carcinoma of the stomach in Southeast Asian women (6.7), for the liver in East Asian men (6.8), for the gall bladder in Indian women (3.8), for the pancreas in North African men (2.2), for large cell carcinoma of the lung in former Yugoslavian men (4.2), for pleural mesothelioma in Turkish women (23.8), for the cervix in Danes (1.6), for seminoma in Chileans (2.1), for transitional-cell carcinoma of the bladder in Asian Arab men (2.3), for meningioma in former Yugoslavians (1.3), and for papillary carcinoma of the thyroid in East and Southeast Asian men (3.6). No immigrant groups had an increased risk of breast, uterus, ovary, and prostate cancers or nervous system tumors. The HRs for all breast cancers were between 1.0 in low-risk Europeans and 1.2 in lowest-risk non-Europeans. Low-risk non-Europeans had an HR of 2.9 for lobular carcinoma. Low

  18. Analyses and thought on countermeasures for the family formation trend among floating population in Wuhan city.

    PubMed

    Chen, X; Sun, L

    1997-01-01

    The familized floating population in China consists of families formed from blood kinship networks of floating population. This study examines the size of the familized floating population in Wuhan City in 1995 and the negative impacts for urban management, supplies, family planning, education, and employment. Floating population families are formed due to the presence of rural and urban differences, the desire for income, and a goal of permanent urban residence with family stability and steady economic gains. Data were obtained from a 1% sample survey among the floating population who lived in rented, borrowed, or self-built houses or apartments for over 6 months. 69.2% of the floating population, or 335,000 people, were familized floating population. 55.01% of the familized floating population were women, and 60.41% of the laborers were women. 33.50% of the women who "should" be employed were not. 50% of the women in some districts were unemployed. 30.61% were children under 14 years of age. The dependency burden for the employed floating population was greater than for the urban employed population. The birth rate among the familized floating population was 44.60%. 89.59% of women aged older than 15 years in the familized floating population were of childbearing age. Most had a low level of education. The floating population creates the need for educating 15,000 new students every year; this requires construction of 10 new schools every year. The floating population increases the need to produce more electricity, clothing, food, houses, and other services or facilities. The floating population brings norms about a higher family size, which challenges urban residents' beliefs and impedes smooth implementation of the family planning policy. Management needs to regulate population flow, reduce consumption, and control family formation and childbearing. Management needs to increase mobility costs. PMID:12320985

  19. Asian Americans: America's Fastest Growing Minority Group. Population Trends and Public Policy. Number 19.

    ERIC Educational Resources Information Center

    O'Hare, William P.; Felt, Judy C.

    Newly available statistical data from the March 1990 Supplement of the Current Population Survey (CPS) indicates that Asians and Pacific Islanders were the fastest growing minority group in the United States during the 1980s. While the size of the Asian American population trails behind the Hispanic American and Black populations, changes in…

  20. Population of the United States, Trends and Prospects: 1950-1990. Series P-23, No. 49.

    ERIC Educational Resources Information Center

    Bureau of the Census (DOC), Suitland, MD. Population Div.

    This document, one of the series of United States Current Population Reports, is also a part of a series of "country statements," prepared as background material for the World Population Conference held in August 1974, which describe the demographic situations of approximately 57 cooperating countries. The population situation is presented as a…

  1. Partitioning the sources of demographic variation reveals density-dependent nest predation in an island bird population

    PubMed Central

    Sofaer, Helen R; Sillett, T Scott; Langin, Kathryn M; Morrison, Scott A; Ghalambor, Cameron K

    2014-01-01

    Ecological factors often shape demography through multiple mechanisms, making it difficult to identify the sources of demographic variation. In particular, conspecific density can influence both the strength of competition and the predation rate, but density-dependent competition has received more attention, particularly among terrestrial vertebrates and in island populations. A better understanding of how both competition and predation contribute to density-dependent variation in fecundity can be gained by partitioning the effects of density on offspring number from its effects on reproductive failure, while also evaluating how biotic and abiotic factors jointly shape demography. We examined the effects of population density and precipitation on fecundity, nest survival, and adult survival in an insular population of orange-crowned warblers (Oreothlypis celata) that breeds at high densities and exhibits a suite of traits suggesting strong intraspecific competition. Breeding density had a negative influence on fecundity, but it acted by increasing the probability of reproductive failure through nest predation, rather than through competition, which was predicted to reduce the number of offspring produced by successful individuals. Our results demonstrate that density-dependent nest predation can underlie the relationship between population density and fecundity even in a high-density, insular population where intraspecific competition should be strong. PMID:25077023

  2. Rabbits killing birds revisited.

    PubMed

    Zhang, Jimin; Fan, Meng; Kuang, Yang

    2006-09-01

    We formulate and study a three-species population model consisting of an endemic prey (bird), an alien prey (rabbit) and an alien predator (cat). Our model overcomes several model construction problems in existing models. Moreover, our model generates richer, more reasonable and realistic dynamics. We explore the possible control strategies to save or restore the bird by controlling or eliminating the rabbit or the cat when the bird is endangered. We confirm the existence of the hyperpredation phenomenon, which is a big potential threat to most endemic prey. Specifically, we show that, in an endemic prey-alien prey-alien predator system, eradication of introduced predators such as the cat alone is not always the best solution to protect endemic insular prey since predator control may fail to protect the indigenous prey when the control of the introduced prey is not carried out simultaneously. PMID:16529776

  3. Birds, Examining Your Environment.

    ERIC Educational Resources Information Center

    MacBean, John C.; And Others

    Designed to provide new and different ways of observing birds rather than simply identifying them, this book attempts to develop skills for how to look at birds. Activities in each of the four sections, "Live Birds,""Birds' Eggs,""Birds' Nests," and "Dead Birds," are specifically planned to get one involved with birds in their natural environment.…

  4. Do unpaved, low-traffic roads affect bird communities?

    NASA Astrophysics Data System (ADS)

    Mammides, Christos; Kounnamas, Constantinos; Goodale, Eben; Kadis, Costas

    2016-02-01

    Unpaved, low traffic roads are often assumed to have minimal effects on biodiversity. To explore this assertion, we sampled the bird communities in fifteen randomly selected sites in Pafos Forest, Cyprus and used multiple regression to quantify the effects of such roads on the total species richness. Moreover, we classified birds according to their migratory status and their global population trends, and tested each category separately. Besides the total length of unpaved roads, we also tested: a. the site's habitat diversity, b. the coefficient of variation in habitat (patch) size, c. the distance to the nearest agricultural field, and d. the human population size of the nearest village. We measured our variables at six different distances from the bird point-count locations. We found a strong negative relationship between the total bird richness and the total length of unpaved roads. The human population size of the nearest village also had a negative effect. Habitat diversity was positively related to species richness. When the categories were tested, we found that the passage migrants were influenced more by the road network while resident breeders were influenced by habitat diversity. Species with increasing and stable populations were only marginally affected by the variables tested, but the effect of road networks on species with decreasing populations was large. We conclude that unpaved and sporadically used roads can have detrimental effects on the bird communities, especially on vulnerable species. We propose that actions are taken to limit the extent of road networks within protected areas, especially in sites designated for their rich avifauna, such as Pafos Forest, where several of the affected species are species of European and global importance.

  5. Absolute consistency: individual versus population variation in annual-cycle schedules of a long-distance migrant bird.

    PubMed

    Conklin, Jesse R; Battley, Phil F; Potter, Murray A

    2013-01-01

    Flexibility in scheduling varies throughout an organism's annual cycle, reflecting relative temporal constraints and fitness consequences among life-history stages. Time-selection can act at different scales, either by limiting the range of alternative strategies in the population, or by increasing the precision of individual performance. We tracked individual bar-tailed godwits Limosa lapponica baueri for two full years (including direct observation during non-breeding seasons in New Zealand and geolocator tracking of round-trip migrations to Alaska) to present a full annual-cycle view of molt, breeding, and migration schedules. At both population and individual scales, temporal variation was greater in post-breeding than pre-breeding stages, and greater in molts than in movements, but schedules did not tighten across successive stages of migration toward the breeding grounds. In general, individual godwits were quite consistent in timing of events throughout the year, and repeatability of pre-breeding movements was particularly high (r = 0.82-0.92). However, we demonstrate that r values misrepresent absolute consistency by confounding inter- and intra-individual variation; the biological significance of r values can only be understood when these are considered separately. By doing so, we show that some stages have considerable tolerance for alternative strategies within the population, whereas scheduling of northbound migratory movements was similar for all individuals. How time-selection simultaneously shapes both individual and population variation is central to understanding and predicting adaptive phenological responses to environmental change. PMID:23342168

  6. Kit fox population trends at the Naval Petroleum Reserves in California

    SciTech Connect

    Kato, T.T.; Scrivner, J.H.; Warrick, G.; Cypher, B.

    1991-01-01

    The San Joaquin kit fox was listed as an endangered subspecies following passage of the Endangered Species Protection Act of 1966, and further classified as rare under the California Endangered Species Act of 1970. The San Joaquin kit fox occurs on the Naval Petroleum Reserves in California administered by the Department of Energy (DOE). A long term kit fox population monitoring program was initiated as part of DOE's mitigation strategy to comply with the Endangered Species Act. In addition to monitoring kit fox populations, the program includes assessments of kit fox prey density and assessments of predator abundance. The objectives of this study were to: describe the long term changes in the kit fox population on the Reserves and assess the roles of coyotes and lagomorphs in kit fox population dynamics. When the fox population on NPR-1 declined between 1980 and 1984, it appeared to have been negatively impacted by a declining prey base (lagomorphs) and an increasing coyote population. Declining lagomorph densities may have been a more important factor because as coyote numbers declined between 1985 and 1990, the kit fox population remained stable. The fox population on NPR-2 remained at a higher and more stable level than the population on NPR-1. The factors determining the higher densities and greater stability of the fox population on NPR-2 are unknown.

  7. TRENDS IN DENTAL VISITS AMONG THE US NON-INSTITUTIONALIZED CIVILIAN POPULATION: FINDINGS FROM BRFSS 1995 – 2008

    PubMed Central

    Lucas-Perry, Evelyn

    2013-01-01

    Objective To examine the 13-year trend in annual dental care utilization among the US non-institutionalized civilian population. Methods Data from the BRFSS from 1995–2008 for adults’ age 18 and older were abstracted and analyzed using the NIDCR/CDC data query system. Point-estimates, confidence-intervals, trends and differences in trends for self-reported annual dental visits by socio-demographic factors and behavioral factor (smoking) were tested with chi-square tests using Stata® (v11). Results The overall, median percent of reported dental visits increased marginally (1.3%; p=0.99) from 68.6% (66.2%, 70.9%) in 1995 to 69.9% (69.1%, 71.7%) in 2008. Trend lines remained flat for most age groups except for those aged 65 and older, which showed a steady rise from 58.9% (52.9%, 64.9%) in 1995 to 66.3% (63.9%, 68.7%) in 2008. Disparities in median annual dental visits between non-Hispanic whites and other racial/ethnic groups increased from a range of a 2–7% point difference (1995) to a 7–11% point difference (2008). A higher percentage of women relative to men reported a visit 70.1% (66.9%, 73.2%) vs. 66.6 % (63.8%, 69.3%) in 1995 and 71.2% (69.2%, 73.2%) vs. 67.4% (65.0%, 69.7%) in 2008; trends and differences in trends among gender remained similar over time (4–5%). No meaningful change in reported dental visit by race/ethnicity; income, education or smoking was seen. Conclusion Over 13 years, the proportion of persons visiting a dentist has remained relatively constant. Of note is that disparities in dental visits by socio-demographic factors also remained the same over time. PMID:24416728

  8. Estimating Size and Trend of the North Interlake Woodland Caribou Population Using Fecal-DNA and Capture-Recapture Models.

    PubMed

    Hettinga, Peter N; Arnason, Arni Neil; Manseau, Micheline; Cross, Dale; Whaley, Kent; Wilson, Paul J

    2012-08-01

    A critical step in recovery efforts for endangered and threatened species is the monitoring of population demographic parameters. As part of these efforts, we evaluated the use of fecal-DNA based capture-recapture methods to estimate population sizes and population rate of change for the North Interlake woodland caribou herd (Rangifer tarandus caribou), Manitoba, Canada. This herd is part of the boreal population of woodland caribou, listed as threatened under the federal Species at Risk Act (2003) and the provincial Manitoba Endangered Species Act (2006). Between 2004 and 2009 (9 surveys), we collected 1,080 fecal samples and identified 180 unique genotypes (102 females and 78 males). We used a robust design survey plan with 2 surveys in most years and analysed the data with Program MARK to estimate encounter rates (p), apparent survival rates (ϕ), rates of population change (λ), and population sizes (N). We estimated these demographic parameters for males and females and for 2 genetic clusters within the North Interlake. The population size estimates were larger for the Lower than the Upper North Interlake area and the proportion of males was lower in the Lower (33%) than the Upper North Interlake (49%). Population rate of change for the entire North Interlake area (2005-2009) using the robust design Pradel model was significantly <1.0 (λ = 0.90, 95% CI: 0.82-0.99) and varied between sex and area with the highest being for males in Lower North Interlake (λ = 0.98, 95% CI: 0.83-1.13) and the lowest being for females in Upper North Interlake (λ = 0.83, 95% CI: 0.69-0.97). The additivity of λ between sex and area is supported on the log scale and translates into males having a λ that is 0.09 greater than females and independent of sex, Lower North Interlake having a λ that is 0.06 greater than Upper North Interlake. Population estimates paralleled these declining trends, which correspond to trends observed in other fragmented populations of woodland caribou

  9. Estimating Size and Trend of the North Interlake Woodland Caribou Population Using Fecal-DNA and Capture–Recapture Models

    PubMed Central

    Hettinga, Peter N; Arnason, Arni Neil; Manseau, Micheline; Cross, Dale; Whaley, Kent; Wilson, Paul J

    2012-01-01

    A critical step in recovery efforts for endangered and threatened species is the monitoring of population demographic parameters. As part of these efforts, we evaluated the use of fecal-DNA based capture–recapture methods to estimate population sizes and population rate of change for the North Interlake woodland caribou herd (Rangifer tarandus caribou), Manitoba, Canada. This herd is part of the boreal population of woodland caribou, listed as threatened under the federal Species at Risk Act (2003) and the provincial Manitoba Endangered Species Act (2006). Between 2004 and 2009 (9 surveys), we collected 1,080 fecal samples and identified 180 unique genotypes (102 females and 78 males). We used a robust design survey plan with 2 surveys in most years and analysed the data with Program MARK to estimate encounter rates (p), apparent survival rates (ϕ), rates of population change (λ), and population sizes (N). We estimated these demographic parameters for males and females and for 2 genetic clusters within the North Interlake. The population size estimates were larger for the Lower than the Upper North Interlake area and the proportion of males was lower in the Lower (33%) than the Upper North Interlake (49%). Population rate of change for the entire North Interlake area (2005–2009) using the robust design Pradel model was significantly <1.0 (λ = 0.90, 95% CI: 0.82–0.99) and varied between sex and area with the highest being for males in Lower North Interlake (λ = 0.98, 95% CI: 0.83–1.13) and the lowest being for females in Upper North Interlake (λ = 0.83, 95% CI: 0.69–0.97). The additivity of λ between sex and area is supported on the log scale and translates into males having a λ that is 0.09 greater than females and independent of sex, Lower North Interlake having a λ that is 0.06 greater than Upper North Interlake. Population estimates paralleled these declining trends, which correspond to trends observed in other fragmented populations of

  10. Longevity Trends in the Older Population of Louisiana with Residence Comparisons.

    ERIC Educational Resources Information Center

    Kwan, Yui-Huen; Bertrand, Alvin L.

    Utilizing Louisiana State Bureau of Vital Statistics and U.S. Census data, longevity trends with residence comparisons were examined for all persons 65 or over who died between 1962 and 1974, who were Louisiana residents at the time of death, and whose death was not due to external violence. Every third year in the 12 year period was arbitrarily…

  11. Trends and Implications of Proposed Changes to the "DSM-5" for Vulnerable Populations

    ERIC Educational Resources Information Center

    Miller, Raissa; Prosek, Elizabeth A.

    2013-01-01

    The revision process for the "Diagnostic and Statistical Manual of Mental Disorders" (4th ed., text rev.; American Psychiatric Association, 2000) has increased consciousness for the role of diagnosis in counseling. In this article, the authors discuss 3 trends of the proposed changes: the influence of the medical model, the attention to…

  12. Interaction between maternal effects: onset of incubation and offspring sex in two populations of a passerine bird.

    PubMed

    Badyaev, Alexander V; Hill, Geoffrey E; Beck, Michelle L

    2003-05-01

    Maternal phenotype and maternal environment can profoundly affect the phenotype and fitness of offspring. Yet the causes of variation in such maternal effects are rarely known. Embryos in avian eggs cannot develop without being incubated and this creates an opportunity for maternal control of duration and onset of offspring development. However, females might adjust the start of incubation (e.g., coincident with the first egg or delayed until after egg-laying) in response to environmental conditions that they experience at the time of breeding. We studied two populations of the house finch ( Carpodacus mexicanus) that breed at the climatic extremes of the species' geographical range (Montana and Alabama) and found that in both populations, the timing of incubation onset was closely associated with the bias in the sequence in which male and female eggs were laid within a clutch. When females started incubation with the first egg, they produced sons and daughters in highly biased sequence, when females delayed the onset of incubation until after the egg-laying, the sequence of sons and daughters was not biased. Because in both populations, onset of incubation was associated with the ambient temperature, these results emphasize that maternal effects on offspring can be influenced by ecological conditions experienced by parental generation. PMID:12721828

  13. The role of social and ecological processes in structuring animal populations: a case study from automated tracking of wild birds

    PubMed Central

    Farine, Damien R.; Firth, Josh A.; Aplin, Lucy M.; Crates, Ross A.; Culina, Antica; Garroway, Colin J.; Hinde, Camilla A.; Kidd, Lindall R.; Milligan, Nicole D.; Psorakis, Ioannis; Radersma, Reinder; Verhelst, Brecht; Voelkl, Bernhard; Sheldon, Ben C.

    2015-01-01

    Both social and ecological factors influence population process and structure, with resultant consequences for phenotypic selection on individuals. Understanding the scale and relative contribution of these two factors is thus a central aim in evolutionary ecology. In this study, we develop a framework using null models to identify the social and spatial patterns that contribute to phenotypic structure in a wild population of songbirds. We used automated technologies to track 1053 individuals that formed 73 737 groups from which we inferred a social network. Our framework identified that both social and spatial drivers contributed to assortment in the network. In particular, groups had a more even sex ratio than expected and exhibited a consistent age structure that suggested local association preferences, such as preferential attachment or avoidance. By contrast, recent immigrants were spatially partitioned from locally born individuals, suggesting differential dispersal strategies by phenotype. Our results highlight how different scales of social decision-making, ranging from post-natal dispersal settlement to fission–fusion dynamics, can interact to drive phenotypic structure in animal populations. PMID:26064644

  14. The role of social and ecological processes in structuring animal populations: a case study from automated tracking of wild birds.

    PubMed

    Farine, Damien R; Firth, Josh A; Aplin, Lucy M; Crates, Ross A; Culina, Antica; Garroway, Colin J; Hinde, Camilla A; Kidd, Lindall R; Milligan, Nicole D; Psorakis, Ioannis; Radersma, Reinder; Verhelst, Brecht; Voelkl, Bernhard; Sheldon, Ben C

    2015-04-01

    Both social and ecological factors influence population process and structure, with resultant consequences for phenotypic selection on individuals. Understanding the scale and relative contribution of these two factors is thus a central aim in evolutionary ecology. In this study, we develop a framework using null models to identify the social and spatial patterns that contribute to phenotypic structure in a wild population of songbirds. We used automated technologies to track 1053 individuals that formed 73 737 groups from which we inferred a social network. Our framework identified that both social and spatial drivers contributed to assortment in the network. In particular, groups had a more even sex ratio than expected and exhibited a consistent age structure that suggested local association preferences, such as preferential attachment or avoidance. By contrast, recent immigrants were spatially partitioned from locally born individuals, suggesting differential dispersal strategies by phenotype. Our results highlight how different scales of social decision-making, ranging from post-natal dispersal settlement to fission-fusion dynamics, can interact to drive phenotypic structure in animal populations. PMID:26064644

  15. International Conservation Policy Delivers Benefits for Birds in Europe

    NASA Astrophysics Data System (ADS)

    Donald, Paul F.; Sanderson, Fiona J.; Burfield, Ian J.; Bierman, Stijn M.; Gregory, Richard D.; Waliczky, Zoltan

    2007-08-01

    Conservation of the planet's biodiversity will depend on international policy intervention, yet evidence-based assessment of the success of such intervention is lacking. Poor understanding of the effectiveness of international policy instruments exposes them to criticism or abandonment and reduces opportunities to improve them. Comparative analyses of population trends provide strong evidence for a positive impact of one such instrument, the European Union's Birds Directive, and we identify positive associations between the rate of provision of certain conservation measures through the directive and the response of bird populations. The results suggest that supranational conservation policy can bring measurable conservation benefits, although future assessments will require the setting of quantitative objectives and an increase in the availability of data from monitoring schemes.

  16. Resource Trends and Population Policy: A Time for Reassessment. Worldwatch Paper 29.

    ERIC Educational Resources Information Center

    Brown, Lester R.

    Population growth and resource depletion are discussed. The need is stressed for policy makers to understand how population projections relate to the carrying capacity of the earth's basic biological systems. Because the earth's resources are limited, it is essential that policy makers in developed and developing nations be able to analyze the…

  17. Rural California Communities: Trends in Latino Population and Community Life. JSRI Statistical Brief No. 7.

    ERIC Educational Resources Information Center

    Allensworth, Elaine; Rochin, Refugio I.

    The relationships among community characteristics and community well-being were examined for all 366 rural California communities with a population of 1,000-2,000. High proportions of Latinos and new immigrants in a community population were positively related to unemployment, percent children, and employment in agriculture, and negatively related…

  18. Time trend in depression diagnoses among acute coronary syndrome patients and a reference population from 2001 to 2009 in Denmark.

    PubMed

    Jørgensen, Terese Sara Høj; Mårtensson, Solvej; Ibfelt, Else Helene; Jørgensen, Martin Balslev; Wium-Andersen, Ida Kim; Wium-Andersen, Marie Kim; Prescott, Eva; Osler, Merete

    2016-07-01

    Introduction In the last decade a range of recommendations to increase awareness of depression in acute coronary syndrome patients have been published. To test the impact of those recommendations we examine and compare recent time trends in depression among acute coronary syndrome patients and a reference population. Methods 87 218 patients registered with acute coronary syndrome from 2001-2009 in Denmark and a match reference population were followed through hospital registries and medication prescriptions for early (≤30 days), intermediate (31 days to 6 months) and later (6 months to 2 years) depression in the acute coronary syndrome population and overall depression in the reference population. Cox regression models were used to compare hazard ratios (HRs) for depression over calendar years. Results During the study period, 11.0% and 6.2% were diagnosed with depression in the acute coronary syndrome population and in the reference population, respectively. For the acute coronary syndrome population, the adjusted HRs increased for early (HR (95% CI) 1.04 (1.01-1.06)) and intermediate depression (HR (95% CI) 1.01 (1.00-1.03)), whereas the adjusted HRs did not change for later depression (HR (95% CI) 0.99 (0.98-1.00)). For the reference population the adjusted HRs for depression increased through the study period (HR (95% CI) 1.01 (1.01-1.03)). Conclusion Increase in diagnoses of depressions within 6 months of acute coronary syndrome may be explained by increased focus on depression in this patient group in combination with increased awareness of depression in the general population. PMID:26750515

  19. Concentrations and time trends of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in aquatic bird eggs from San Francisco Bay, CA 2000-2003.

    PubMed

    She, Jianwen; Holden, Arthur; Adelsbach, Terrence L; Tanner, Manon; Schwarzbach, Steven E; Yee, Julie L; Hooper, Kim

    2008-08-01

    Concentrations of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in 169 avian eggs. We analyzed randomly collected eggs of two species of piscivorous birds: Caspian tern (Sterna caspia) (n=78) and Forster's tern (Sterna forsteri) (n=76). We also analyzed fail-to-hatch eggs from two species protected under the Federal Endangered Species Act of 1973, that breed in the San Francisco Bay region: the piscivorous California Least tern (Sterna antillarum brownii) (n=11) and the omnivorous California Clapper rail (Rallus longirostris obsoletus) (n=4). San Francisco Bay eggs were collected annually for four years (2000-2003), and additional 20 eggs were collected and analyzed from Gray's Harbor, Washington in 2001. Geometric mean PBDE concentrations did not significantly differ in the three tern species, but concentrations in eggs from the fail to hatch California Clapper rail eggs were significantly lower than those found in the randomly collected tern eggs. Median concentrations of SigmaPBDEs in Caspian tern eggs for 2000-2003 were 2410, 4730, 3720 and 2880 ng/g lipid weight (lw), respectively, in Forster's terns 1820, 4380, 5460 and 3600 ng/g lw, respectively, and in California Least terns for 2001 and 2002 were 5060 and 5170 ng/g lw, respectively. In contrast, median SigmaPBDEs concentration in California Clapper rail eggs for 2001 was 379 ng/g lw. Five PBDEs were the major congeners found and decreased in the order BDE-47, -99, -100, -153, and -154. BDE-32, -28, -71, -66, -85, -183 were less prevalent, minor congeners, as was BDE-209, which was measured in a subset of samples. PBDE concentrations in bird eggs from San Francisco Bay were site related. There was no significant difference in PBDE concentrations in Caspian tern eggs from San Francisco Bay and Gray's Harbor, WA. Average PBDE concentrations in eggs did not significantly increase over the period 2000-2003. PMID:18466953

  20. Concentrations and time trends of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in aquatic bird eggs from San Francisco Bay, CA 2000-2003

    USGS Publications Warehouse

    She, J.; Holden, A.; Adelsbach, T.L.; Tanner, M.; Schwarzbach, S.E.; Yee, J.L.; Hooper, K.

    2008-01-01

    Concentrations of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in 169 avian eggs. We analyzed randomly collected eggs of two species of piscivorous birds: Caspian tern (Sterna caspia) (n = 78) and Forster's tern (Sterna forsteri) (n = 76). We also analyzed fail-to-hatch eggs from two species protected under the Federal Endangered Species Act of 1973, that breed in the San Francisco Bay region: the piscivorous California Least tern (Sterna antillarum brownii) (n = 11) and the omnivorous California Clapper rail (Rallus longirostris obsoletus) (n = 4). San Francisco Bay eggs were collected annually for four years (2000-2003), and additional 20 eggs were collected and analyzed from Gray's Harbor, Washington in 2001. Geometric mean PBDE concentrations did not significantly differ in the three tern species, but concentrations in eggs from the fail to hatch California Clapper rail eggs were significantly lower than those found in the randomly collected tern eggs. Median concentrations of ???PBDEs in Caspian tern eggs for 2000-2003 were 2410, 4730, 3720 and 2880 ng/g lipid weight (lw), respectively, in Forster's terns 1820, 4380, 5460 and 3600 ng/g lw, respectively, and in California Least terns for 2001 and 2002 were 5060 and 5170 ng/g lw, respectively. In contrast, median ???PBDEs concentration in California Clapper rail eggs for 2001 was 379 ng/g lw. Five PBDEs were the major congeners found and decreased in the order BDE-47, -99, -100, -153, and -154. BDE-32, -28, -71, -66, -85, -183 were less prevalent, minor congeners, as was BDE-209, which was measured in a subset of samples. PBDE concentrations in bird eggs from San Francisco Bay were site related. There was no significant difference in PBDE concentrations in Caspian tern eggs from San Francisco Bay and Gray's Harbor, WA. Average PBDE concentrations in eggs did not significantly increase over the period 2000-2003. ?? 2008 Elsevier Ltd. All rights reserved.

  1. Population-based incidence trends of oropharyngeal and oral cavity cancers by sex among the poorest and underprivileged populations

    PubMed Central

    2014-01-01

    Background Oral cancer is an important health issue, with changing incidence in many countries. Oropharyngeal cancer (OPC, in tonsil and oropharygeal areas) is increasing, while oral cavity cancer (OCC, other sites in the mouth) is decreasing. There is the need to identify high risk groups and communities for further study and intervention. The objective of this study was to determine how the incidence of OPC and OCC varied by neighbourhood socioeconomic status (SES) in British Columbia (BC), including the magnitude of any inequalities and temporal trends. Methods ICDO-3 codes were used to identify OPC and OCC cases in the BC Cancer Registry from 1981–2010. Cases were categorized by postal codes into SES quintiles (q1-q5) using VANDIX, which is a census-based, multivariate weighted index based on neighbourhood average household income, housing tenure, educational attainment, employment and family structure. Age-standardized incidence rates were determined for OPC and OCC by sex and SES quintiles and temporal trends were then examined. Results Incidence rates are increasing in both men and women for OPC, and decreasing in men and increasing in women for OCC. This change is not linear or proportionate between different SES quintiles, for there is a sharp and dramatic increase in incidence according to the deprivation status of the neighbourhood. The highest incidence rates in men for both OPC and OCC were observed in the most deprived SES quintile (q5), at 1.7 times and 2.2 times higher, respectively, than men in the least deprived quintile (q1). For OPC, the age-adjusted incidence rates significantly increased in all SES quintiles with the highest increase observed in the most deprived quintile (q5). Likewise, the highest incidence rates for both OPC and OCC in women were observed in the most deprived SES quintile (q5), at 2.1 times and 1.8 times higher, respectively, than women in the least deprived quintile (q1). Conclusion We report on SES disparities in oral

  2. Distribution and density of bird species hazardous to aircraft

    USGS Publications Warehouse

    Robbins, C.S.

    1975-01-01

    Only in the past 5 years has it become feasible to map the relative abundance of North American birds. Two programs presently under way and a third that is in the experimental phase are making possible the up-to-date mapping of abundance as well as distribution. A fourth program that has been used successfully in Europe and on a small scale in parts of North America yields detailed information on breeding distribution. The Breeding Bird Survey, sponsored by the U.S. Bureau of Sport Fisheries and Wildlife and the Canadian Wildlife Service, involves 2,000 randomly distributed roadside counts that are conducted during the height of the breeding season in all U.S. States and Canadian Provinces. Observations of approximately 1.4 million birds per year are entered on magnetic tape and subsequently used both for statistical analysis of population trends and for computer mapping of distribution and abundance. The National Audubon Society's Christmas Bird Count is conducted in about 1,000 circles, each 15 miles (24 km) in diameter, in the latter half of December. Raw data for past years have been published in voluminous reports, but not in a form for ready analysis. Under a contract between the U.S. Air Force and the U. S. Bureau of Sport Fisheries and Wildlife (in cooperation with the National Audubon Society), preliminary maps showing distribution and abundance of selected species that are potential hazards to aircraft are presently being mapped and prepared for publication. The Winter Bird Survey, which is in its fifth season of experimental study in a limited area in Central Maryland, may ultimately replace the Christmas Bird Count source. This Survey consists of a standardized 8-kilometer (5-mile) route covered uniformly once a year during midwinter. Bird Atlas programs, which map distribution but not abundance, are well established in Europe and are gaining interest in America

  3. Effects of cave gating on population trends at individual hibernacula of the Indiana bat (Myotis sodalist)

    USGS Publications Warehouse

    Crimmins, Shawn M.; McKann, Patrick C.; Szymanski, Jennifer A.; Thogmartin, Wayne E.

    2014-01-01

    Installing gates at cave entrances to protect hibernating bat colonies is a widespread conservation action, particularly for endangered bat species such as the Indiana bat (Myotis sodalis). However, there is surprisingly little evidence on the efficacy of gates for improving population growth rates. We used change-point models to determine the effects of gate construction on Indiana bats. We estimated population growth rates at 20 hibernacula pre- and post-gating and quantified the change in population growth rates after gate installation. Hibernacula with increasing growth rates prior to gate placement all experienced decreased growth rates after installation. For hibernacula with declining growth rates prior to construction, growth rates increased moderately after installation. When weighted by population size, average change in growth rates across all 20 hibernacula was negative. Our results suggest that use of gates at hibernacula with growing populations may relate to unintended declines in growth rates but that, at hibernacula with declining populations, installation of gates may lead to moderate increases in local population growth rates.

  4. Cutaneous melanoma frequencies and seasonal trend in 20 years of observation of a population characterised by excessive sun exposure

    PubMed Central

    Bonin, Serena; Albano, Antonio; di Meo, Nicola; Gatti, Alessandro; Stinco, Giuseppe; Zanconati, Fabrizio; Trevisan, Giusto

    2015-01-01

    Background Cutaneous melanoma is an aggressive form of skin cancer. It has become an increasingly common neoplasm in the most developed countries, especially among individuals of European origin. Patients and methods. Anonymous data of patients with cutaneous melanoma were collected from the diagnostic database of the University Hospital of Trieste from 1 January 1990 to 10 December 2013. Our study is based on a population which was constant over the period of observation; it was also well-defined and characterised by unrestrained sun exposure. Results The number of cutaneous melanomas increased during the period of observation with a seasonality trend and gender related differences both for anatomical sites distribution and stage of the disease. Moreover, 6% of our cohort developed multiple melanomas. Conclusions In a well-defined population devoted to excessive sun exposure the frequencies of skin melanomas roughly doubled from 1990 to 2013 following a seasonal trend. In that population, prevention efforts according to gender specific risk behaviour, as well as follow-up programmes both for evaluation of metastatic spreading and for early diagnosis of additional skin melanomas, are crucial due to gender specific differences and to the occurrence of multiple melanomas. PMID:26834525

  5. Considerations for monitoring raptor population trends based on counts of migrants

    USGS Publications Warehouse

    Titus, K.; Fuller, M.R.; Ruos, J.L.

    1989-01-01

    Various problems were identified with standardized hawk count data as annually collected at six sites. Some of the hawk lookouts increased their hours of observation from 1979-1985, thereby confounding the total counts. Data recording and missing data hamper coding of data and their use with modern analytical techniques. Coefficients of variation among years in counts averaged about 40%. The advantages and disadvantages of various analytical techniques are discussed including regression, non-parametric rank correlation trend analysis, and moving averages.

  6. Declining trends in prevalence of Helicobacter pylori infection by birth-year in a Japanese population.

    PubMed

    Watanabe, Miki; Ito, Hidemi; Hosono, Satoyo; Oze, Isao; Ashida, Chieko; Tajima, Kazuo; Katoh, Hisato; Matsuo, Keitaro; Tanaka, Hideo

    2015-12-01

    Gastric cancer incidence and mortality have been decreasing in Japan. These decreases are likely due to a decrease in prevalence of Helicobacter pylori infection. Our aim was to characterize the trends in prevalence of H. pylori infection focused on birth-year. We carried out a cross-sectional study that included 4285 subjects who were born from 1926 to 1989. We defined H. pylori infection by the serum H. pylori antibody titer. Individuals having H. pylori infection and those with negative H. pylori antibody titer and positive pepsinogen test were defined as high-risk individuals for gastric cancer. We estimated the birth-year percent change (BPC) of the prevalence by Joinpoint regression analysis. The prevalence of H. pylori infection among the subjects born from 1927 to 1949 decreased from 54.0% to 42.0% with a BPC of -1.2%. It was followed by a rapid decline in those born between 1949 (42.0%) and 1961 (24.0%) with a BPC of -4.5%, which was followed by those born between 1961 (24.0%) and 1988 (14.0%) with a BPC of -2.1%. The proportion of high-risk individuals for gastric cancer among the subjects born from 1927 to 1942 decreased from 62.0% to 55.0% with a BPC of -0.8%. A subsequent rapid declining trend was observed in those born between 1942 (55.0%) and 1972 (18.0%) with a BPC of -3.6%, and then it became stable. These remarkable declining trends in the prevalence of H. pylori infection by birth-year would be useful to predict the future trend in gastric cancer incidence in Japan. PMID:26395018

  7. Temporal trends in ankyloglossia and frenotomy in British Columbia, Canada, 2004-2013: a population-based study

    PubMed Central

    Joseph, K.S.; Kinniburgh, Brooke; Metcalfe, Amy; Razaz, Neda; Sabr, Yasser; Lisonkova, Sarka

    2016-01-01

    Background: Routine surveillance of congenital anomalies has shown recent increases in ankyloglossia (tongue-tie) in British Columbia, Canada. We examined the temporal trends in ankyloglossia and its surgical treatment (frenotomy). Methods: We conducted a population-based cohort study involving all live births in British Columbia from Apr. 1, 2004, to Mar. 31, 2014, with data obtained from the province's Perinatal Data Registry. Spatiotemporal trends in ankyloglossia and frenotomy, and associations with maternal and infant characteristics, were quantified using logistic regression analysis. Results: There were 459 445 live births and 3022 cases of ankyloglossia between 2004 and 2013. The population incidence of ankyloglossia increased by 70% (rate ratio 1.70, 95% confidence interval [CI] 1.44-2.01), from 5.0 per 1000 live births in 2004 to 8.4 per 1000 in 2013. During the same period, the population rate of frenotomy increased by 89% (95% CI 52%-134%), from 2.8 per 1000 live births in 2004 to 5.3 per 1000 in 2013. The 2 regional health authorities with the lowest population rates of frenotomy (1.5 and 1.8 per 1000 live births) had the lowest rates of ankyloglossia and the lowest rates of frenotomy among cases with ankyloglossia, whereas the 2 regional health authorities with the highest population rates of frenotomy (5.2 and 5.3 per 1000 live births) had high rates of ankyloglossia and the highest rates of frenotomy among cases of ankyloglossia. Nulliparity, multiple birth, male infant sex, birth weight and year were independently associated with ankyloglossia. Interpretation: Large temporal increases and substantial spatial variations in ankyloglossia and frenotomy rates were observed that may indicate a diagnostic suspicion bias and increasing use of a potentially unnecessary surgical procedure among infants. PMID:27280112

  8. Effects of distance from cattle water developments on grassland birds

    USGS Publications Warehouse

    Fontaine, A.L.; Kennedy, P.L.; Johnson, D.H.

    2004-01-01

    Many North American grassland bird populations appear to be declining, which may be due to changes in grazing regimes on their breeding areas. Establishment of water developments and confining cattle (Bos taurus L.) to small pastures often minimizes spatial heterogeneity of cattle forage consumption, which may lead to uniformity in vegetative structure. This increased uniformity may provide suitable habitat for some bird species but not others. We assessed how cattle use, vegetative structure, and bird population densities varied with increasing distance from water developments (0-800 m) on the Little Missouri National Grassland (LMNG) in North Dakota. Lark buntings (Calamospiza melancorys Stejneger), which are typically associated with low vegetative cover, decreased with increasing distance from water developments. Horned larks (Eremophila alpestris L.), also a low-cover associate, followed a similar but weaker trend. Densities of another low-cover associate as well as moderate- and high-cover associates were not related to distance from water. Vegetative height-density and litter depth increased by 50 and 112%, respectively, while cowpie cover and structural variability decreased by 51 and 24%, respectively, with distance from water. Confidence interval overlap was common among all measures, showing substantial variability among study sites. Our results indicate cattle use is higher closer to water developments, and this pattern may positively affect the densities of lark buntings and horned larks. The absence of density gradients in the other bird species may be due to the paucity of locations > 800 m from water on the LMNG.

  9. Effects of distance from cattle water developments on grassland birds

    USGS Publications Warehouse

    Fontaine, A.L.; Kennedy, P.L.; Johnson, D.H.

    2004-01-01

    Many North American grassland bird populations appear to be declining, which may be due to changes in grazing regimes on their breeding areas. Establishment of water developments and confining cattle (Bos taurus L.) to small pastures often minimizes spatial heterogeneity of cattle forage consumption, which may lead to uniformity in vegetative structure. This increased uniformity may provide suitable habitat for some bird species but not others. We assessed how cattle use, vegetative structure, and bird population densities varied with increasing distance from water developments (0DS800 m) on the Little Missouri National Grassland (LMNG) in North Dakota. Lark buntings (Calamospiza melancorys Stejneger), which are typically associated with low vegetative cover, decreased with increasing distance from water developments. Horned larks (Eremophila alpestris L.), also a low-cover associate, followed a similar but weaker trend. Densities of another low-cover associate as well as moderate- and high-cover associates were not related to distance from water. Vegetative height-density and litter depth increased by 50 and 112%, respectively, while cowpie cover and structural variability decreased by 51 and 24%, respectively, with distance from water. Confidence interval overlap was common among all measures, showing substantial variability among study sites. Our results indicate cattle use is higher closer to water developments, and this pattern may positively affect the densities of lark buntings and horned larks. The absence of density gradients in the other bird species may be due to the paucity of locations > 800 m from water on the LMNG.

  10. Estimating Trends of Population Decline in Long-Lived Marine Species in the Mediterranean Sea Based on Fishers' Perceptions

    PubMed Central

    Maynou, Francesc; Sbrana, Mario; Sartor, Paolo; Maravelias, Christos; Kavadas, Stefanos; Damalas, Dimitros; Cartes, Joan E.; Osio, Giacomo

    2011-01-01

    We conducted interviews of a representative sample of 106 retired fishers in Italy, Spain and Greece, asking specific questions about the trends they perceived in dolphin and shark abundances between 1940 and 1999 (in three 20 year periods) compared to the present abundance. The large marine fauna studied were not target species of the commercial fleet segment interviewed (trawl fishery). The fishers were asked to rank the perceived abundance in each period into qualitative ordinal classes based on two indicators: frequency of sightings and frequency of catches (incidental or intentional) of each taxonomic group. The statistical analysis of the survey results showed that both incidental catches and the sighting frequency of dolphins have decreased significantly over the 60+ years of the study period (except for in Greece due to the recent population increase). This shows that fishers' perceptions are in agreement with the declining population trends detected by scientists. Shark catches were also perceived to have diminished since the early 1940s for all species. Other long-lived Mediterranean marine fauna (monk seals, whales) were at very low levels in the second half of the 20th century and no quantitative data could be obtained. Our study supports the results obtained in the Mediterranean and other seas that show the rapid disappearance (over a few decades) of marine fauna. We show that appropriately designed questionnaires help provide a picture of animal abundance in the past through the valuable perceptions of fishers. This information can be used to complement scientific sources or in some cases be taken as the only information source for establishing population trends in the abundance of sensitive species. PMID:21818268

  11. The MASSIVE Survey. II. Stellar Population Trends Out to Large Radius in Massive Early-type Galaxies

    NASA Astrophysics Data System (ADS)

    Greene, Jenny E.; Janish, Ryan; Ma, Chung-Pei; McConnell, Nicholas J.; Blakeslee, John P.; Thomas, Jens; Murphy, Jeremy D.

    2015-07-01

    We examine stellar population gradients in ˜100 massive early-type galaxies spanning 180\\lt {σ }*\\lt 370 km s-1 and MK of -22.5 to -26.5 mag, observed as part of the MASSIVE survey. Using integral-field spectroscopy from the Mitchell Spectrograph on the 2.7 m telescope at McDonald Observatory, we create stacked spectra as a function of radius for galaxies binned by their stellar velocity dispersion, stellar mass, and group richness. With excellent sampling at the highest stellar mass, we examine radial trends in stellar population properties extending to beyond twice the effective radius (˜ 2.5 {R}{e}). Specifically, we examine trends in age, metallicity, and abundance ratios of Mg, C, N, and Ca, and discuss the implications for star formation histories and elemental yields. At a fixed physical radius of 3-6 kpc (the likely size of the galaxy cores formed at high redshift), stellar age and [α/Fe] increase with increasing {σ }* and depend only weakly on stellar mass, as we might expect if denser galaxies form their central cores earlier and faster. If we instead focus on 1-1.5 {R}{e}, the trends in abundance and abundance ratio are washed out, as might be expected if the stars at large radius were accreted by smaller galaxies. Finally, we show that when controlling for {σ }*, there are only very subtle differences in stellar population properties or gradients as a function of group richness; even at large radius, internal properties matter more than environment in determining star formation history.

  12. Population trends and survival of nesting green sea turtles Chelonia mydas on Aves Island, Venezuela

    USGS Publications Warehouse

    Garcia-Cruz, Marco A.; Lampo, Margarita; Penaloza, Claudia L.; Kendall, William; Solé, Genaro; Rodriguez-Clark, Kathryn M.

    2015-01-01

    Long-term demographic data are valuable for assessing the effect of anthropogenic impacts on endangered species and evaluating recovery programs. Using a 2-state open robust design model, we analyzed mark-recapture data from green turtles Chelonia mydas sighted between 1979 and 2009 on Aves Island, Venezuela, a rookery heavily impacted by human activities before it was declared a wildlife refuge in 1972. Based on the encounter histories of 7689 nesting females, we estimated the abundance, annual survival, and remigration intervals for this population. Female survival varied from 0.14-0.91, with a mean of 0.79, which is low compared to survival of other populations from the Caribbean (mean = 0.84) and Australia (mean = 0.95), even though we partially corrected for tag loss, which is known to negatively bias survival estimates. This supports prior suggestions that Caribbean populations in general, and the Aves Island population in particular, may be more strongly impacted than populations elsewhere. It is likely that nesters from this rookery are extracted while foraging in remote feeding grounds where hunting still occurs. Despite its relatively low survival, the nesting population at Aves Island increased during the past 30 years from approx. 500 to >1000 nesting females in 2009. Thus, this population, like others in the Caribbean and the Atlantic, seems to be slowly recovering following protective management. Although these findings support the importance of long-term conservation programs aimed at protecting nesting grounds, they also highlight the need to extend management actions to foraging grounds where human activities may still impact green turtle populations.

  13. Spatial synchrony of local populations has increased in association with the recent Northern Hemisphere climate trend.

    PubMed

    Post, Eric; Forchhammer, Mads C

    2004-06-22

    According to ecological theory, populations whose dynamics are entrained by environmental correlation face increased extinction risk as environmental conditions become more synchronized spatially. This prediction is highly relevant to the study of ecological consequences of climate change. Recent empirical studies have indicated, for example, that large-scale climate synchronizes trophic interactions and population dynamics over broad spatial scales in freshwater and terrestrial systems. Here, we present an analysis of century-scale, spatially replicated data on local weather and the population dynamics of caribou in Greenland. Our results indicate that spatial autocorrelation in local weather has increased with large-scale climatic warming. This increase in spatial synchrony of environmental conditions has been matched, in turn, by an increase in the spatial synchrony of local caribou populations toward the end of the 20th century. Our results indicate that spatial synchrony in environmental conditions and the populations influenced by them are highly variable through time and can increase with climatic warming. We suggest that if future warming can increase population synchrony, it may also increase extinction risk. PMID:15197267

  14. Prevalence and secular trends in obesity in Pacific and Indian Ocean island populations.

    PubMed

    Hodge, A M; Dowse, G K; Zimmet, P Z; Collins, V R

    1995-09-01

    Surveys conducted in 10 Pacific island populations and in the multiethnic populations of Mauritius and Rodrigues in the Indian Ocean have provided data on the prevalence of obesity, potential etiological factors and medical hazards associated with obesity. The results indicate that the prevalence of obesity (by body mass index (BMI) in some of these populations is among the highest in the world. Obesity related to degree of modernization is more common in urban than in rural locations and tends to be found more often in women. In two populations where longitudinal data were available, there were dramatic increases in prevalence over relatively short time periods. Obesity contributed to the risk of non-insulin-dependent diabetes mellitus (NIDDM) and was associated with other risk factors for cardiovascular disease (CVD) in all populations, but no relationship could be found with total mortality in three ethnic groups for whom data were available. A genetic susceptibility to obesity combined with social pressures that favor high energy intakes and reduced physical activity are believed to be important in these populations. The challenge for the future lies in developing culturally appropriate programs for preventing obesity and thus reducing associated morbidity, while continuing to research its behavioral and genetic determinants. PMID:8581792

  15. Abundance trends and status of the Little Colorado River population of humpback chub

    USGS Publications Warehouse

    Coggins, L.G., Jr.; Pine, William E., III; Walters, C.J.; Van Haverbeke, D. R.; Ward, D.; Johnstone, H.C.

    2006-01-01

    The abundance of the Little Colorado River population of federally listed humpback chub Gila cypha in Grand Canyon has been monitored since the late 1980s by means of catch rate indices and capture-recapture-based abundance estimators. Analyses of data from all sources using various methods are consistent and indicate that the adult population has declined since monitoring began. Intensive tagging led to a high proportion (>80%) of the adult population being marked by the mid-1990s. Analysis of these data using both closed and open abundance estimation models yields results that agree with catch rate indices about the extent of the decline. Survival rates for age-2 and older fish are age dependent but apparently not time dependent. Back-calculation of recruitment using the apparent 1990s population age structure implies periods of higher recruitment in the late 1970s to early 1980s than is now the case. Our analyses indicate that the U.S. Fish and Wildlife Service recovery criterion of stable abundance is not being met for this population. Also, there is a critical need to develop new abundance indexing and tagging methods so that early, reliable, and rapid estimates of humpback chub recruitment can be obtained to evaluate population responses to management actions designed to facilitate the restoration of Colorado River native fish communities. ?? Copyright by the American Fisheries Society 2006.

  16. Sampling-variance effects on detecting density dependence from temporal trends in natural populations

    USGS Publications Warehouse

    Shenk, T.M.; White, Gary C.; Burnham, K.P.

    1998-01-01

    Monte Carlo simulations were conducted to evaluate robustness of four tests to detect density dependence, from series of population abundances, to the addition of sampling variance. Population abundances were generated from random walk, stochastic exponential growth, and density-dependent population models. Population abundance estimates were generated with sampling variances distributed as lognormal and constant coefficients of variation (cv) from 0.00 to 1.00. In general, when data were generated under a random walk, Type I error rates increased rapidly for Bulmer's R, Pollard et al.'s, and Dennis and Taper's tests with increasing magnitude of sampling variance for n > 5 yr and all values of process variation. Bulmer's R* test maintained a constant 5% Type I error rate for n > 5 yr and all magnitudes of sampling variance in the population abundance estimates. When abundances were generated from two stochastic exponential growth models (R = 0.05 and R = 0.10), Type I errors again increased with increasing sampling variance; magnitude of Type I error rates were higher for the slower growing population. Therefore, sampling error inflated Type I error rates, invalidating the tests, for all except Bulmer's R* test. Comparable simulations for abundance estimates generated from a density-dependent growth rate model were conducted to estimate power of the tests. Type II error rates were influenced by the relationship of initial population size to carrying capacity (K), length of time series, as well as sampling error. Given the inflated Type I error rates for all but Bulmer, s R*, power was overestimated for the remaining tests, resulting in density: dependence being detected more often than it existed. Population abundances of natural populations are almost exclusively estimated rather than censused, assuring sampling error. Therefore, because these tests have been shown to be either invalid when only sampling variance occurs in the population abundances (Bulmer's R

  17. Use of reverse transcriptase polymerase chain reaction (RT-PCR) in molecular screening of Newcastle disease virus in poultry and free-living bird populations.

    PubMed

    Carrasco, Adriano de Oliveira Torres; Rodrigues, Juliana Nogueira Martins; Seki, Meire Christina; de Moraes, Fabricio Edgar; Silva, Jaqueline Raymondi; Durigon, Edison Luis; Pinto, Aramis Augusto

    2013-02-01

    The aim of this study was to evaluate a simple molecular method of reverse transcriptase polymerase chain reaction (RT-PCR) to differentiate Newcastle disease virus strains according to their pathogenicity, in order to use it in molecular screening of Newcastle disease virus in poultry and free-living bird populations. Specific primers were developed to differentiate LaSota--LS--(vaccine strain) and Sao Joao do Meriti--SJM--strain (highly pathogenic strain). Chickens and pigeons were experimentally vaccinated/infected for an in vivo study to determine virus shedding in feces. Validation of sensitivity and specificity of the primers (SJM and LS) by experimental models used in the present study and results obtained in the molecular analysis of the primers by BLAST made it possible to generalize results. The development of primers that differentiate the level of pathogenicity of NDV stains is very important, mainly in countries where real-time RT-PCR is still not used as a routine test. These primers were able to determine the presence of the agent and to differentiate it according to its pathogenicity. PMID:22983878

  18. [TRENDS IN HEALTH OF THE POPULATION IN THE AREA OF THE TENGIZ FIELD].

    PubMed

    Kenessaryiev, U I; Yerzhanova, A E; Kenessary, D U; Amrin, M K; Dosmukhametov, A T; Baimukhamedov, A A

    2015-01-01

    At the present the Caspian oil and gas field became extremely important for the economy of Kazakhstan and it has entered a qualitatively new stage of its development. In connection with the intensive development of these fields the attention of both scientists and health practitioners is attracted by problems of populations' health. In the article there are presented data of a study of the quality of main objects of environment, health condition, demographic indices of and morbidity rate of the population of the Zhylyoi district of the Atyrau region. The population resides in the region of influence of the Tengiz oil and gas field. The level of mortality in Zhylyoi for the periodfrom 2006 to 2013 was establishe to decline, as birth rate rather increased. Indices of the population's structure retain the tendency to the progressive type, possibly in relation with urbanization and industrial migration of population, that increased in last years. The district mortality rates are below national, regional and urban values. Natural population growth in Zhylyoi has increased by 27.6%. The analysis of primary morbidity of the population of the Zhylyoi district in dynamics from 2006 to 2013 shows a some decrease. In the structure of the morbidity there was noted a decrease in the proportion of diseases of the skin and subcutaneous tissue, respiratory diseases, digestive organs. However, the proportion of blood diseases, diseases of the hematopoietic system and blood flow has increased. Alongside this in the region there is clearly discernible the scarcity of doctors, qualified nurses and beds. PMID:26856157

  19. The North American Breeding Bird Survey 1966–2011: Summary analysis and species accounts

    USGS Publications Warehouse

    Sauer, John R.; Link, William A.; Fallon, Jane E.; Pardieck, Keith L.; Ziolkowski, David J.

    2013-01-01

    The North American Breeding Bird Survey is a roadside, count-based survey conducted by volunteer observers. Begun in 1966, it now is a primary source of information on spatial and temporal patterns of population change for North American birds. We analyze population change for states, provinces, Bird Conservation Regions, and the entire survey within the contiguous United States and southern Canada for 426 species using a hierarchical log-linear model that controls for observer effects in counting. We also map relative abundance and population change for each species using a spatial smoothing of data at the scale of survey routes. We present results in accounts that describe major breeding habitats, migratory status, conservation status, and population trends for each species at several geographic scales. We also present composite results for groups of species categorized by habitats and migratory status. The survey varies greatly among species in percentage of species' range covered and precision of results, but consistent patterns of decline occur among eastern forest, grassland, and aridland obligate birds while generalist bird species are increasing.

  20. Trends in postcoronary artery bypass graft sternal wound dehiscence in a provincial population

    PubMed Central

    Doherty, Christopher; Nickerson, Duncan; Southern, Danielle A; Kieser, Teresa; Appoo, Jehangir; Dawes, Jeffery; De Souza, Michael A; Harrop, Alan R; Rabi, Doreen

    2014-01-01

    BACKGROUND: It appears that the medical profile of patients undergoing coronary artery bypass graft (CABG) surgery has changed. The impact of this demographic shift on CABG outcomes, such as sternal wound dehiscence, is unclear. OBJECTIVES: To quantify the incidence and trends of sternal wound dehiscence, quantify the demographic shift of those undergoing CABG and identify patient factors predictive of disease. METHODS: A prospective analysis was performed on a historical cohort of consecutive patients who underwent CABG (without valve replacement) in Alberta between April 1, 2002 and November 30, 2009. The incidence and trends of sternal wound dehiscence were determined. In addition, the trend of the mean Charlson index score and European System for Cardiac Operative Risk Evaluation (EuroSCORE) (capturing patient comorbidities) was analyzed. Univariable analysis and multivariable models were performed to determine factors predictive of wound dehiscence. RESULTS: A total of 5815 patients underwent CABG during the study period. The incidence proportion of sternal wound dehiscence in Alberta was 1.86% and the incidence rate was 1.98 cases per 100 person-years. Although both the EuroSCORE and Charlson scores significantly increased over the study period, the incidence of sternal wound dehiscence did not change significantly. Factors predictive of sternal wound dehiscence were diabetes (OR 2.97 [95% CI 1.73 to 5.10]), obesity (OR 1.55 [95% CI 1.05 to 2.27]) and female sex (OR 1.90 [95% CI 1.26 to 2.87]). CONCLUSIONS: The incidence proportion of sternal wound dehiscence in Alberta was comparable with the incidence previously published in the literature. While patients undergoing CABG had worsening medical profiles, the incidence of sternal wound dehiscence did not appear to be increasing significantly. PMID:25332650

  1. Temporal trends in daily dietary intakes of DDTs and HCHs in urban populations from Beijing and Shenyang, China.

    PubMed

    Yu, Yanxin; Wang, Bin; Wang, Xilong; Liu, Wenxin; Cao, Jun; Wong, Minghong; Tao, Shu

    2013-06-01

    The temporal trends in daily dietary exposure of the populations in Beijing and Shenyang, China to DDTs and HCHs through consumption of various food categories and the associated health risks were investigated in this work. The estimated dietary intakes of DDTs and HCHs in 2005/2007 were almost one and two orders of magnitude lower than those in 1992 and in the 1970s, respectively, revealing the historical decrease of DDT and HCH in Chinese foods after their applications were banned. The relative contributions of different foodstuffs to the overall intakes of DDTs and HCHs in the 1970s and in 1992 were very different from those in 2005/2007, mainly due to the remarkable concentration variance in foodstuffs and changes in diet habit of population. According to the hazard guidelines, it is concluded that intakes of these two pesticides in 2005/2007 may not exert adverse effects on human health. PMID:23427859

  2. Carry-over effects of the social environment on future divorce probability in a wild bird population.

    PubMed

    Culina, Antica; Hinde, Camilla A; Sheldon, Ben C

    2015-10-22

    Initial mate choice and re-mating strategies (infidelity and divorce) influence individual fitness. Both of these should be influenced by the social environment, which determines the number and availability of potential partners. While most studies looking at this relationship take a population-level approach, individual-level responses to variation in the social environment remain largely unstudied. Here, we explore carry-over effects on future mating decisions of the social environment in which the initial mating decision occurred. Using detailed data on the winter social networks of great tits, we tested whether the probability of subsequent divorce, a year later, could be predicted by measures of the social environment at the time of pairing. We found that males that had a lower proportion of female associates, and whose partner ranked lower among these, as well as inexperienced breeders, were more likely to divorce after breeding. We found no evidence that a female's social environment influenced the probability of divorce. Our findings highlight the importance of the social environment that individuals experience during initial pair formation on later pairing outcomes, and demonstrate that such effects can be delayed. Exploring these extended effects of the social environment can yield valuable insights into processes and selective pressures acting upon the mating strategies that individuals adopt. PMID:26468239

  3. Urban Bird Feeding: Connecting People with Nature

    PubMed Central

    Gaston, Kevin J.

    2016-01-01

    At a time of unprecedented biodiversity loss, researchers are increasingly recognizing the broad range of benefits provided to humankind by nature. However, as people live more urbanized lifestyles there is a progressive disengagement with the natural world that diminishes these benefits and discourages positive environmental behaviour. The provision of food for garden birds is an increasing global phenomenon, and provides a readily accessible way for people to counter this trend. Yet despite its popularity, quite why people feed birds remains poorly understood. We explore three loosely defined motivations behind bird feeding: that it provides psychological benefits, is due to a concern about bird welfare, and/or is due to a more general orientation towards nature. We quantitatively surveyed households from urban towns in southern England to explore attitudes and actions towards garden bird feeding. Each household scored three Likert statements relating to each of the three motivations. We found that people who fed birds regularly felt more relaxed and connected to nature when they watched garden birds, and perceived that bird feeding is beneficial for bird welfare while investing time in minimising associated risks. Finally, feeding birds may be an expression of a wider orientation towards nature. Overall, we found that the feelings of being relaxed and connected to nature were the strongest drivers. As urban expansion continues both to threaten species conservation and to change peoples’ relationship with the natural world, feeding birds may provide an important tool for engaging people with nature to the benefit of both people and conservation. PMID:27427988

  4. Urban Bird Feeding: Connecting People with Nature.

    PubMed

    Cox, Daniel T C; Gaston, Kevin J

    2016-01-01

    At a time of unprecedented biodiversity loss, researchers are increasingly recognizing the broad range of benefits provided to humankind by nature. However, as people live more urbanized lifestyles there is a progressive disengagement with the natural world that diminishes these benefits and discourages positive environmental behaviour. The provision of food for garden birds is an increasing global phenomenon, and provides a readily accessible way for people to counter this trend. Yet despite its popularity, quite why people feed birds remains poorly understood. We explore three loosely defined motivations behind bird feeding: that it provides psychological benefits, is due to a concern about bird welfare, and/or is due to a more general orientation towards nature. We quantitatively surveyed households from urban towns in southern England to explore attitudes and actions towards garden bird feeding. Each household scored three Likert statements relating to each of the three motivations. We found that people who fed birds regularly felt more relaxed and connected to nature when they watched garden birds, and perceived that bird feeding is beneficial for bird welfare while investing time in minimising associated risks. Finally, feeding birds may be an expression of a wider orientation towards nature. Overall, we found that the feelings of being relaxed and connected to nature were the strongest drivers. As urban expansion continues both to threaten species conservation and to change peoples' relationship with the natural world, feeding birds may provide an important tool for engaging people with nature to the benefit of both people and conservation. PMID:27427988

  5. Estimating grizzly and black bear population abundance and trend in Banff National Park using noninvasive genetic sampling.

    PubMed

    Sawaya, Michael A; Stetz, Jeffrey B; Clevenger, Anthony P; Gibeau, Michael L; Kalinowski, Steven T

    2012-01-01

    We evaluated the potential of two noninvasive genetic sampling methods, hair traps and bear rub surveys, to estimate population abundance and trend of grizzly (Ursus arctos) and black bear (U. americanus) populations in Banff National Park, Alberta, Canada. Using Huggins closed population mark-recapture models, we obtained the first precise abundance estimates for grizzly bears (N= 73.5, 95% CI = 64-94 in 2006; N= 50.4, 95% CI = 49-59 in 2008) and black bears (N= 62.6, 95% CI = 51-89 in 2006; N= 81.8, 95% CI = 72-102 in 2008) in the Bow Valley. Hair traps had high detection rates for female grizzlies, and male and female black bears, but extremely low detection rates for male grizzlies. Conversely, bear rubs had high detection rates for male and female grizzlies, but low rates for black bears. We estimated realized population growth rates, lambda, for grizzly bear males (λ= 0.93, 95% CI = 0.74-1.17) and females (λ= 0.90, 95% CI = 0.67-1.20) using Pradel open population models with three years of bear rub data. Lambda estimates are supported by abundance estimates from combined hair trap/bear rub closed population models and are consistent with a system that is likely driven by high levels of human-caused mortality. Our results suggest that bear rub surveys would provide an efficient and powerful means to inventory and monitor grizzly bear populations in the Central Canadian Rocky Mountains. PMID:22567089

  6. Secular trends in the relationship between surnames in a population: Study of a border town.

    PubMed

    Román-Busto, J; Fuster, V

    2015-04-01

    The study of surnames in a territory over time is an opportunity to obtain knowledge of the evolution of allelic frequencies. Geographic and cultural factors influence the renovation of surnames and reflect accelerations or delays in the gene flow. Political borders may also condition the genetic structure of a population. Using isonymy, this paper studies the evolution (from 1750 to 2006) of the frequencies of surnames and the components of inbreeding in Olivenza, a border town whose sovereignty was transferred from Portugal to Spain in 1801. After the change in dominion the number of Portuguese surnames fell sharply and the expected values for a population so close to Portugal recovered only after a long period of time. The results indicate that although the border has made population movement more difficult, and has therefore had an impact on the rate of gene exchange, a certain gene flow with Portugal persisted. PMID:25659892

  7. Population, development, and the environment: trends and key issues in the developed countries.

    PubMed

    Commoner, B

    1993-01-01

    The quantitative relationship between environmental degradation (pollution) and the factors that influence it can be expressed by the identity: Pollution = population x (good/population) x (pollution/good), where "affluence" is expressed as good/population and the technology of production as pollution/good. Annual data for the emission of carbon monoxide and nitrogen oxides from mobile sources and for the use of pesticides and inorganic nitrogen fertilizer from agriculture, for the member countries of the Organization for Economic Cooperation and Development and the United States, were analyzed to determine the relative change in the three factors over the period 1970-1987. In each case the considerable variation in pollutant emissions among the different countries is most closely related to the concomitant change in the technology factor (pollution/good). In contrast, there is much less variation among the countries in the population and "affluence" factors, which are consequently uncorrelated with the variation in pollutant emissions. The data show that the change in production technology is by far the most important of the several factors responsible for changes in pollution emission. PMID:8375953

  8. Use of geographic information systems to depict and analyze mosquito population trends.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mosquitoes transmit (vector) disease agents that cause malaria, yellow fever, dengue, West Nile fever, and encephalitis. Spread of these diseases is controlled by the management of mosquito population levels, changes in which are monitored in vector surveillance programs by the use of mechanical tr...

  9. Ten-Year Trend Analysis of Autism Severity: A Nationwide Population-Based Register Study

    ERIC Educational Resources Information Center

    Lin, Jin-Ding; Sung, Chang-Lin; Lin, Lan-Ping; Hsu, Shang-Wei; Chien, Wu-Chien; Su, Sui-Lung; Wu, Jia-Ling

    2011-01-01

    The severity of autism spectrum disorder was strongly related to the education and service outcome. Without a clear profile of autistic population and its change, efforts to understand its nature and improve the quality of service or education will be impossible. The present study aims to describe the over time reported rate of autism severity…

  10. World Population Trends: Signs of Hope, Signs of Stress. Worldwatch Paper 8.

    ERIC Educational Resources Information Center

    Brown, Lester R.

    The interrelationship of population growth, food production, and death rates is explored. Birth rates in China, Western Europe, and North America have significantly decreased in the five-year period from 1970-75. This is largely due to widening availability of family planning services and the growing desire to use them. Four European countries…

  11. Trend in Obesity Prevalence in European Adult Cohort Populations during Follow-up since 1996 and Their Predictions to 2015

    PubMed Central

    von Ruesten, Anne; Steffen, Annika; Floegel, Anna; van der A, Daphne L.; Masala, Giovanna; Tjønneland, Anne; Halkjaer, Jytte; Palli, Domenico; Wareham, Nicholas J.; Loos, Ruth J. F.; Sørensen, Thorkild I. A.; Boeing, Heiner

    2011-01-01

    Objective To investigate trends in obesity prevalence in recent years and to predict the obesity prevalence in 2015 in European populations. Methods Data of 97 942 participants from seven cohorts involved in the European Prospective Investigation into Cancer and Nutrition (EPIC) study participating in the Diogenes project (named as “Diogenes cohort” in the following) with weight measurements at baseline and follow-up were used to predict future obesity prevalence with logistic linear and non-linear (leveling off) regression models. In addition, linear and leveling off models were fitted to the EPIC-Potsdam dataset with five weight measures during the observation period to find out which of these two models might provide the more realistic prediction. Results During a mean follow-up period of 6 years, the obesity prevalence in the Diogenes cohort increased from 13% to 17%. The linear prediction model predicted an overall obesity prevalence of about 30% in 2015, whereas the leveling off model predicted a prevalence of about 20%. In the EPIC-Potsdam cohort, the shape of obesity trend favors a leveling off model among men (R2 = 0.98), and a linear model among women (R2 = 0.99). Conclusion Our data show an increase in obesity prevalence since the 1990ies, and predictions by 2015 suggests a sizeable further increase in European populations. However, the estimates from the leveling off model were considerably lower. PMID:22102897

  12. Trends in the Population Prevalence of People Who Inject Drugs in US Metropolitan Areas 1992–2007

    PubMed Central

    Tempalski, Barbara; Pouget, Enrique R.; Cleland, Charles M.; Brady, Joanne E.; Cooper, Hannah L. F.; Hall, H. Irene; Lansky, Amy; West, Brooke S.; Friedman, Samuel R.

    2013-01-01

    Background People who inject drugs (PWID) have increased risk of morbidity and mortality. We update and present estimates and trends of the prevalence of current PWID and PWID subpopulations in 96 US metropolitan statistical areas (MSAs) for 1992–2007. Current estimates of PWID and PWID subpopulations will help target services and help to understand long-term health trends among PWID populations. Methodology We calculated the number of PWID in the US annually from 1992–2007 and apportioned estimates to MSAs using multiplier methods. We used four types of data indicating drug injection to allocate national annual totals to MSAs, creating four distinct series of component estimates of PWID in each MSA and year. The four component estimates are averaged to create the best estimate of PWID for each MSA and year. We estimated PWID prevalence rates for three subpopulations defined by gender, age, and race/ethnicity. We evaluated trends using multi-level polynomial models. Results PWID per 10,000 persons aged 15–64 years varied across MSAs from 31 to 345 in 1992 (median 104.4) to 34 to 324 in 2007 (median 91.5). Trend analysis indicates that this rate declined during the early period and then was relatively stable in 2002–2007. Overall prevalence rates for non-Hispanic black PWID increased in 2005 as compared to other racial/ethnic groups. Hispanic prevalence, in contrast, declined across time. Importantly, results show a worrisome trend in young PWID prevalence since HAART was initiated – the mean prevalence was 90 to 100 per 10,000 youth in 1992–1996, but increased to >120 PWID per 10,000 youth in 2006–2007. Conclusions Overall, PWID rates remained constant since 2002, but increased for two subpopulations: non-Hispanic black PWID and young PWID. Estimates of PWID are important for planning and evaluating public health programs to reduce harm among PWID and for understanding related trends in social and health outcomes. PMID:23755143

  13. Lead poisoning in wild birds from southern Spain: a comparative study of wetland areas and species affected, and trends over time.

    PubMed

    Mateo, R; Green, A J; Lefranc, H; Baos, R; Figuerola, J

    2007-01-01

    We studied lead (Pb) shot contamination in sediments from the Guadalquivir marshes and six other closed-basin lagoons in Southern Spain that are of major importance for threatened species of waterbirds. Shot densities were relatively low in Doñana, ranging from 0 to 25 shot/m(2) in the top 10 cm of sediments. The density at Medina lagoon (Ramsar site) was 148 shot/m(2), making it the most contaminated wetland known in Europe. Densities in the other five lagoons ranged from 9 to 59 shot/m(2). We studied the prevalence of ingested Pb shot in waterbirds from Doñana and found a lower prevalence in ducks than previously recorded in other Spanish wetlands. Lead shot were also found embedded in tissues of some waterbirds, proving that protected species such as the greater flamingo (Phoenicopterus ruber) and the glossy ibis (Plegadis falcinellus) are subjected to illegal hunting. The prevalence of embedded shot for geese was especially high (44% for trapped birds). Lead shot were detected in 2.8% of the pellets of the Spanish imperial eagle (Aquila adalberti) which usually preys on geese. We found that the prevalence of ingested Pb shot in geese and in Spanish imperial eagles has significantly decreased in recent years, possibly due to restrictions on hunting activity, efforts to remove shot from a sand dune used by geese to obtain grit, and to the high rainfall in Doñana during the last years that permitted waterfowl to stay more within the protected areas. PMID:16483652

  14. Current Characteristics and Trends of the Tracked Satellite Population in the Human Space Flight Regime

    NASA Technical Reports Server (NTRS)

    Johnson, Nicholas L.

    2006-01-01

    Since the end of the Apollo program in 1972, human space flight has been restricted to altitudes below 600 km above the Earth s surface with most missions restricted to a ceiling below 400 km. An investigation of the tracked satellite population transiting and influencing the human space flight regime during the past 11 years (equivalent to a full solar cycle) has recently been completed. The overall effects of satellite breakups and solar activity are typically less pronounced in the human space flight regime than other regions of low Earth orbit. As of January 2006 nearly 1500 tracked objects resided in or traversed the human space flight regime, although two-thirds of these objects were in orbits of moderate to high eccentricity, significantly reducing their effect on human space flight safety. During the period investigated, the spatial density of tracked objects in the 350-400 km altitude regime of the International Space Station demonstrated a steady decline, actually decreasing by 50% by the end of the period. On the other hand, the region immediately above 600 km experienced a significant increase in its population density. This regime is important for future risk assessments, since this region represents the reservoir of debris which will influence human space flight safety in the future. The paper seeks to put into sharper perspective the risks posed to human space flight by the tracked satellite population, as well as the influences of solar activity and the effects of compliance with orbital debris mitigation guidelines on human space flight missions. Finally, the methods and successes of characterizing the population of smaller debris at human space flight regimes are addressed.

  15. Fifty-year trends in a box turtle population in Maryland

    USGS Publications Warehouse

    Hall, R.J.; Henry, P.F.P.; Bunck, C.M.

    1999-01-01

    A survey conducted in 1995 investigated long term declines reported in a population of box turtles Terrapene Carolina monitored each decade since 1945 in bottomland hardwood forest at the Patuxent Wildlife Research Center, Maryland. Methods duplicated past surveys in most respects, but were supplemented by radiotelemetry and a survey of dominant vegetation. Seventy different turtles were found on the 11.8 ha study area, a decline of >75% since peak populations were recorded in 1955. Searchers were less efficient in 1995 than in 1945-1975 for a variety of possible reasons. Among turtles recorded, approximately equal numbers persisted from each of the past five decades, with some individuals surviving >70 years. A sex ratio strongly favoring males was first recorded in 1975 and continued in 1995, but juveniles and subadults were found in greater proportion in 1995 than in any other survey. Six of nine radio-marked turtles left the bottomland study area and migrated to the adjoining bluffs to hibernate, suggesting more extensive movements and perhaps less stable home ranges than formerly thought. Age structure of trees indicated a gradual change to more shade-tolerant species. Examination of rates of change from survey data suggested that major losses probably resulted from changes in hydrology that exacerbated flooding in 1972, with recovery only beginning in 1995 and perhaps limited both by repeated flood events and successional changes in the forest. Slow recovery from losses may indicate that populations of the species would respond poorly to exploitation.

  16. Time trends of smoking cessation: a micro-population computer simulation model.

    PubMed

    Elketroussi, M; Fan, D P

    1992-10-01

    The Micro-population model of Risk-group Dynamics (MRD) approaches smoking behavior at the level of the individual and integrates physiological and social factors to describe the evolution of behavior change in the population. MRD is innovative in several ways: (1) the model describes mathematically the interactions among these behavioral factors; (2) the model accounts for both the variability of these factors among different persons and the universality of basic rules describing these factors in all individuals; and (3) the model can be applied to various types of populations and a wide range of intervention strategies. MRD combines the physiological, psychological and social determinants into a hazard function for relapse to smoking. This hazard function is then organized into a three term expression incorporating: a baseline hazard characteristic to each individual, a decreasing term for the diminishing aspect of the initial hazard and an effect of external interventions. The model gives promising results when applied to the Multiple Risk Factors Intervention Trial (MRFIT) data using the assumptions of a Weibull distribution for the baseline hazard, a negative exponential for the decrease in the initial hazard and a constant intensity for the external intervention. PMID:1428217

  17. A unified strategy for monitoring changes in abundance of birds associated with North American tidal marshes

    USGS Publications Warehouse

    Conway, C.J.; Droege, S.

    2006-01-01

    An effective approach to species conservation involves efforts to prevent species from becoming threatened with extinction before they become listed as endangered. Standardized monitoring efforts provide the data necessary to estimate population trajectories of many species so that management agencies can identify declining species before they reach the point of endangerment. Species that occur in tidal saltmarshes in North America are under sampled by existing broad-scale monitoring programs. We summarize existing local and regional survey efforts for saltmarsh birds and propose a standardized continental protocol for assessing the status and population trends of birds that breed in saltmarshes in North America. The objective of this proposed survey effort is to create a series of interconnected monitoring efforts that will provide information on the status and the changes in status of terrestrial birds living in saltmarsh systems of North America. We describe detailed field protocols for standardized surveys of saltmarsh birds across North America. We recommend morning point-count surveys with an initial 5-min passive period followed by a period of call broadcast. Surveyors record all individual birds detected (regardless of distance) for all species that are associated with saltmarshes and estimate the distance to each individual bird detected. We provide recommendations for standardizing distance between adjacent survey points, how repeat detections across points are recorded, daily and seasonal timing of surveys, timing of surveys relative to tidal cycles, number of replicate surveys per year, and focal species for this standardized survey effort. Recommended survey protocols include methods that allow estimation of various components of detection probability so that stronger inferences can be made based on trends in count data. We explain why the various survey recommendations are made so that potential participants understand the rationale for various

  18. Infant mortality in three population-based cohorts in Southern Brazil: trends and differentials.

    PubMed

    Santos, Iná S; Menezes, Ana M B; Mota, Denise M; Albernaz, Elaine P; Barros, Aluísio J D; Matijasevich, Alicia; Barros, Fernando C; Victora, Cesar G

    2008-01-01

    We studied time trends in infant mortality and associated factors between three cohort studies carried out in Pelotas, Rio Grande do Sul State, Brazil, in 1982, 1993, and 2004. All hospital births and deaths were determined by means of regular visits to hospitals, registrar's offices, and cemeteries. This data was used to calculate neonatal, post-neonatal, and infant mortality rates per thousand live births. Rates were also calculated according to cause of death, sex, birth weight, gestational age, and family income. The infant mortality rate fell from 36.4 per 1,000 live births in 1982 to 21.1 in 1993 and 19.4 in 2004. Major causes of infant mortality in 2004 were perinatal causes and respiratory infections. Mortality among low birth weight children from poor families fell 16% between 1993 and 2004; however, this rate increased by more than 100% among high-income families due to the increase in the number of preterm deliveries in this group. The stabilization of infant mortality in the last decade is likely to be due to excess medical interventions relating to pregnancies and delivery care. PMID:18797721

  19. Epidemiological Trends of Traumatic Brain Injury Identified in the Emergency Department in a Publicly-Insured Population, 2002-2010

    PubMed Central

    Fu, Terence S.; Jing, Ruwei; Fu, Wayne W.; Cusimano, Michael D.

    2016-01-01

    Objectives To examine epidemiological trends of Traumatic Brain Injury (TBI) treated in the Emergency Department (ED), identify demographic groups at risk of TBI, and determine the factors associated with hospitalization following an ED visit for TBI. Methods A province-wide database was used to identify all ED visits for TBI in Ontario, Canada between April 2002 and March 2010. Trends were analyzed using linear regression, and predictors of hospital admission were evaluated using logistic regression. Results There were 986,194 ED visits for TBI over the eight-year study period, resulting in 49,290 hospitalizations and 1,072 deaths. The age- and sex-adjusted rate of TBI decreased by 3%, from 1,013.9 per 100,000 (95% CI 1,008.3–1,010.6) to 979.1 per 100,000 (95% CI 973.7–984.4; p = 0.11). We found trends towards increasing age, comorbidity level, length of stay, and ambulatory transport use. Children and young adults (ages 5–24) sustained peak rates of motor vehicle crash (MVC) and bicyclist-related TBI, but also experienced the greatest decline in these rates (p = 0.003 and p = 0.005). In contrast, peak rates of fall-related TBI occurred among the youngest (ages 0–4) and oldest (ages 85+) segments of the population, but rates remained stable over time (p = 0.52 and 0.54). The 5–24 age group also sustained the highest rates of sports-related TBI but rates remained stable (p = 0.80). On multivariate analysis, the odds of hospital admission decreased by 1% for each year over the study period (OR = 0.991, 95% CI = 0.987–0.995). Increasing age and comorbidity, male sex, and ambulatory transport were significant predictors of hospital admission. Conclusions ED visits for TBI are involving older populations with increasingly complex comorbidities. While TBI rates are either stable or declining among vulnerable groups such as young drivers, youth athletes, and the elderly, these populations remain key targets for focused injury prevention and surveillance

  20. Trends of contraception among ladies of local population in Pakistan; why, how, when and what?

    PubMed Central

    Atif, Khaula; Afsheen, Afeera; Naqvi, Syed Abid Hassan; Niazi, Saleem Asif; Ullah Khan, Habib

    2016-01-01

    Objective: To analyze trends of use of methods of contraception along with study of impact of various demographic and social factors on contraception in Peshawar, Pakistan. Methods: A cross-sectional descriptive study with random purposive sampling was conducted at Combined Military Hospital Peshawar, from Mar 2015-Nov 2015. Self-designed questionnaire with demographic details and questions pertinent to contraceptive practices was utilized as study instrument. Females reporting to concerned hospital for contraceptive advice and prescription were distributed with questionnaire and written informed consent form. Formal approval was taken from ethical committee of hospital. Data was analyzed via descriptive analysis (SPSS-21), qualitative data was expressed as frequencies and percentages; quantitative as mean±standard deviation (SD). Main outcome variable i-e contraceptive device used; was cross-tabulated with independent variables. Results: Response rate was 53.2% (n-426). Usage of contraceptive device was as follows; 51.2% Nil, 9.4% barriers, 22.3% oral/injectable hormones, 13.4% IUCDs, 3.8% sterilization. There was a strong relationship between type of contraceptives used and age (p<0.001), client’s education (p<0.001), husband’s education (p<0.001), number of children (p<0.001), religion (p0.013), socioeconomic class (p<0.001), and religious beliefs about use of contraceptives (p<0.001). More Muslims considered contraception irreligious than non-Muslims (p 0.02). There was no significant impact of husbands’ pressure to not to use contraceptives on type of contraception practised (p 0.114). Conclusion: Contraceptive devices are under-utilized in the study participants. Multidisciplinary approach should be applied to enhance client education, awareness and counseling to utilize these devices more appropriately and regularly. PMID:27375727

  1. DIFFERENTIAL IMPACT OF WEST NILE VIRUS ON CALIFORNIA BIRDS

    PubMed Central

    Wheeler, Sarah S.; Barker, Christopher M.; Fang, Ying; Armijos, M. Veronica; Carroll, Brian D.; Husted, Stan; Johnson, Wesley O.; Reisen, William K.

    2010-01-01

    The strain of West Nile virus (WNV) currently epidemic in North America contains a genetic mutation elevating its virulence in birds, especially species in the family Corvidae. Although dead American Crows (Corvus brachyrhynchos) have been the hallmark of the epidemic, the overall impact of WNV on North America’s avifauna remains poorly understood and has not been addressed thoroughly in California. Here, we evaluate variation by species in the effect of WNV on California birds from 2004 to 2007 by using (1) seroprevalence in free-ranging birds, (2) percentage of carcasses of each species reported by the public that tested positive for WNV, (3) mortality determined from experimental infections, and (4) population declines detected by trend analysis of Breeding Bird Survey (BBS) data. Using Bayesian linear models, we extrapolate trends in BBS data from 1980–2003 (pre-WNV) to 2004–2007 (post-WNV). We attribute significant declines from expected abundance trends in areas supporting epiornitics to WNV transmission. We combine risk assessed from each of the four data sets to generate an overall score describing WNV risk by species. The susceptibility of California avifauna to WNV varies widely, with overall risk scores ranging from low for the refractory Rock Pigeon (Columba livia) through high for the susceptible American Crow. Other species at high risk include, in descending order, the House Finch (Carpodacus mexicanus), Black-crowned Night-Heron (Nycticorax nycticorax), Western Scrub-Jay (Aphelocoma californica), and Yellow-billed Magpie (Pica nuttalli). Our analyses emphasize the importance of multiple data sources in assessing the effect of an invading pathogen. PMID:20589226

  2. Preliminary forecasts of Pacific bigeye tuna population trends under the A2 IPCC scenario

    NASA Astrophysics Data System (ADS)

    Lehodey, P.; Senina, I.; Sibert, J.; Bopp, L.; Calmettes, B.; Hampton, J.; Murtugudde, R.

    2010-07-01

    An improved version of the spatial ecosystem and population dynamics model SEAPODYM was used to investigate the potential impacts of global warming on tuna populations. The model included an enhanced definition of habitat indices, movements, and accessibility of tuna predators to different vertically migrant and non-migrant micronekton functional groups. The simulations covered the Pacific basin (model domain) at a 2° × 2° geographic resolution. The structure of the model allows an evaluation from multiple data sources, and parameterization can be optimized by adjoint techniques and maximum likelihood using fishing data. A first such optimized parameterization was obtained for bigeye tuna ( Thunnus obesus) in the Pacific Ocean using historical catch data for the last 50 years and a hindcast from a coupled physical-biogeochemical model driven by the NCEP atmospheric reanalysis. The parameterization provided very plausible biological parameter values and a good fit to fishing data from the different fisheries, both within and outside the time period used for optimization. We then employed this model to forecast the future of bigeye tuna populations in the Pacific Ocean. The simulation was driven by the physical-biogeochemical fields predicted from a global marine biogeochemistry - climate simulation. This global simulation was performed with the IPSL climate model version 4 (IPSL-CM4) coupled to the oceanic biogeochemical model PISCES and forced by atmospheric CO 2, from historical records over 1860-2000, and under the SRES A2 IPCC scenario for the 21st century (i.e. atmospheric CO 2 concentration reaching 850 ppm in the year 2100). Potential future changes in distribution and abundance under the IPCC scenario are presented but without taking into account any fishing effort. The simulation showed an improvement in bigeye tuna spawning habitat both in subtropical latitudes and in the eastern tropical Pacific (ETP) where the surface temperature becomes optimal for

  3. 9 CFR 93.104 - Certificate for pet birds, commercial birds, zoological birds, and research birds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Certificate for pet birds, commercial birds, zoological birds, and research birds. 93.104 Section 93.104 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND...

  4. 9 CFR 93.104 - Certificate for pet birds, commercial birds, zoological birds, and research birds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Certificate for pet birds, commercial birds, zoological birds, and research birds. 93.104 Section 93.104 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND...

  5. Birds Kept as Pets

    MedlinePlus

    ... restricts the importation of pet birds from certain countries and enforces a 30-day quarantine for all imported birds except those that come from Canada. People interested in importing pet birds should visit the USDA non-US Origin Pet Bird Importation website . Choosing a bird Match ...

  6. Diving birds

    NASA Astrophysics Data System (ADS)

    Clanet, Christophe; Masson, Lucien; McKinley, Gareth; Cohen, Robert; Ecole polytechnique Collaboration; MIT Collaboration

    2015-11-01

    Many seabirds (gannets, pelicans, gulls, albatrosses) dive into water at high speeds (25 m/s) in order to capture underwater preys. Diving depths of 20 body lengths are reported in the literature. This value is much larger than the one achieved by men, which is of the order of 5. We study this difference by comparing the impact of slender vs bluff bodies. We show that, contrary to bluff bodies, the penetration depth of slender bodies presents a maximum value for a specific impact velocity that we connect to the velocity of diving birds.

  7. Immigrant workers in the United States: recent trends, vulnerable populations, and challenges for occupational health.

    PubMed

    McCauley, Linda A

    2005-07-01

    Immigrant workers are a rapidly growing segment of the U.S. work force, and these increasing numbers have resulted in a different ethnic mix in the work force than in previous decades. Immigrant workers are not a homogenous group, but are over-represented in low-paying occupations. Their diversity and vulnerability present distinct challenges for occupational health nurses. High-risk occupations in which a large proportion of immigrant workers are hired include agriculture, sweatshops, day laborers, and construction. Initiatives needed to improve the working conditions of this vulnerable population include improved surveillance and research, culturally competent care providers, improved health care access, advocacy, and changes in immigration and health policy. PMID:16097105

  8. Conservation of wading birds

    USGS Publications Warehouse

    Kushlan, J.A.

    1996-01-01

    The conservation and management of wading birds has received considerable attention over the past twenty years, through research, population monitoring, habitat protection, and through activities of specialist groups devoted to all three groups, the herons, ibises and allies, and flamingos. While populations are best known in North America, greatest advances in knowledge may have come in Australasia. The status of most species and many populations is now sufficiently known to allow assessment of risk. Conservation and management techniques allow creation of global and regional action plans for conservation of many species. Global action plans are being developed, but few regional plans have been undertaken. Management of nesting sites is now particularly well appreciated. Although known in broad stroke, much remains to be learned about managing feeding habitat. Problems related to disturbance, conflict with humans, habitat loss, contaminants and other environmental stresses remain for some species and many populations. New challenges lie in creating conservation action that account for genetic stocks.

  9. Population trends, growth, and movement of bigmouth buffalo, Ictiobus cyprinellus, in Lake Oahe, 1963-70

    USGS Publications Warehouse

    Moen, Thomas E.

    1974-01-01

    The bigmouth buffalo, Ictiobus cyprinellus, is the most important commercial species in Lake Oahe, a reservoir in the upper Missouri River. The population was dominated by three strong year classes (1959, 1960, and 1962). Estimated population in the fall of 1964 was 540,000 fish of the combined 1959-60 year classes and 5 million of the 1962 year class (equivalent to 81 kg per hectare). Abundance declined irregularly during 1964-70. Annual landings of these two dominant groups during 1965-70 ranged from 149 to 271 metric tons. The total landings during the period amounted to about 151,800 fish of the 1959-60 year classes and 313,000 fish of the 1962 year class. Growth rate was high during the first few years of impoundment and then declined. Males and females grew at about the same rate for the first 4 yr of life, but females were longer and heavier than males at ages V-VIII. At these ages, fish of the 1962 year class were about 10% shorter and 36% lighter than those of the 1959 year class. Growth of tagged and untagged fish was similar. The number of females per male increased with age. Age at maturity increased slightly as growth rate declined. Movement of marked fish was extensive and the recapture of marked fish was directly related to size of fish, location of release, and subsequent fishing pressure; 44% were recaptured downstream from the point of release, and 38% upstream. Females showed a stronger tendency to move downstream than males. Maximum distance traveled was 380 km and maximum rate of travel was 6.4 km per day. Successful reproduction appeared to be associated with flooding of shoreline vegetation during spring and early summer. Inasmuch as little such flooding is expected in the future, annual landings of bigmouth buffalo will probably continue to decline sharply.

  10. Temporal Trends in the Population Attributable Risk for Cardiovascular Disease: The Atherosclerosis Risk in Communities Study

    PubMed Central

    Cheng, Susan; Claggett, Brian; Correia, Andrew W.; Shah, Amil M.; Gupta, Deepak; Skali, Hicham; Ni, Hanyu; Rosamond, Wayne D.; Heiss, Gerardo; Folsom, Aaron R.; Coresh, Josef; Solomon, Scott D.

    2014-01-01

    Background The extent to which relative contributions of traditional cardiovascular factors risk to incident cardiovascular disease (CVD) may have changed over time remains unclear. Methods and Results We studied 13,541 participants (56% women, 26% black) in the Atherosclerosis Risk in Communities Study, aged 52-66 years and free of CVD at exams in 1987-89, 1990-92, 1993-95, or 1996-98. At each exam, we estimated the population attributable risks (PAR) of traditional risk factors (hypertension, diabetes, obesity, hypercholesterolemia, and smoking) for the 10-year incidence of CVD. Overall, the PAR of all risk factors combined appeared to decrease from 1987-89 to 1996-98 (0.58 to 0.53). The combined PAR was higher in women than men in 1987-89 (0.68 vs. 0.51, P<0.001) but not by 1996-98 (0.58 vs. 0.48, P=0.08). The combined PAR was higher in blacks than whites in 1987-89 (0.67 vs. 0.57, P=0.049), and this difference was more pronounced by 1996-98 (0.67 vs. 0.48, P=0.002). By 1996-98, the PAR of hypertension had become higher in women than men (P=0.02) and also appeared higher in blacks than whites (P=0.08). By 1996-98, the PAR of diabetes remained higher in women than men (P<0.0001) and in blacks than whites (P<0.0001). Conclusions The contribution to CVD of all traditional risk factors combined is greater in blacks than whites, and this difference may be increasing. The contributions of hypertension and diabetes remain especially high, in women as well as blacks. These findings underscore the continued need for individual as well as population approaches to CVD risk factor modification. PMID:25210095

  11. Population trends and environmental contaminants in herons in the Tennessee Valley, 1980-81

    USGS Publications Warehouse

    Fleming, W.J.; Pullin, B.P.; Swineford, D.M.

    1984-01-01

    Great Blue Heron (Ardea herodias) eggs (N = 40) collected in 1980 from four of the largest colonies in the Tennessee Valley contained organochlorine pesticide, polychlorinated biphenyl (PCB), and chromium concentrations below those associated with reduced productivity. Low concentrations of organochlorine pesticide and PCB residues also were found in eggs (N = 31) from three of the larger Black-crowned Night-Heron (Nycticorax nycticorax) colonies in the Tennessee Valley. However, DDE concentrations in two of the Black-crowned Night-Heron eggs exceeded levels associated with reduced nesting success. Mercury was found in all eggs of both species with residues ranging to a high of 2.0 ppm; residues of this magnitude have not been identified as reducing nesting success of either of these two species. Green-backed Heron (Butorides striatus) eggs collected in 1981 near a former DDT manufacturing site in the Tennessee Valley had the highest DDE concentrations ever reported for this species; the effect of these high concentrations on productivity is not known. Eggshell thickness of Great Blue Heron, Green-backed Heron, and Black- crowned Night-Heron eggs averaged 7.5%, 7.6%, and 3% thinner, respectively, than shell thickness of eggs collected before 1947. This amount of thinning is not deleterious; intraclutch variation in shell thickness is often this high. Shell thickness in all three species was correlated (P lt 0.1) with DDE concentrations. The number of nesting pairs of Great Blue Herons and Black-crowned Night-Herons at each of the colonies studied has been stable or increasing during the previous decade. These population data, combined with the residue data, suggest that organochlorine pesticides, PCBs, mercury, and chromium are not adversely affecting these populations. However, we did not assess nesting success which would be a requisite for confirming this.

  12. Population and nutrition; implications of sociodemographic trends and differentials for food and nutrition policy in Central America and Panama.

    PubMed

    Teller, C; Sibrian, R; Talavera, C; Bent, V; Del Canto, J; Saenz, L

    1979-01-01

    This paper looks into some of the sociodemographic trends and differentials that may be influencing the lack of improvement in the food and nutrition situation in rural Central America. Evidence is presented that indicates that it is more difficult to reduce malnutrition and fertility than it was to reduce infant and child mortality initially. When sociostructural changes are not forthcoming after the initiation of the mortality decline, then resultant population growth, distribution and composition dynamics can hinder improvement in nutrition. In particular, changes in the social composition differentials as a result of selectivity in mortality, fertility and migration have apparently contributed to the increasing nutrition gap between the well-fed and the poorly-fed classes. PMID:12309615

  13. Evaluating causes of population change in North American insectivorous songbirds

    USGS Publications Warehouse

    Robbins, C.S.

    1962-01-01

    Although the North American Breeding Bird Survey (BBS) is a principal source of information regarding populations of most North American bird species, many features of the survey complicate analysis of population change. Correlation studies based on BBS data cannot be used to unambiguously define cause and effect relationships. Recently, B?hning-Gaese et al. (1993) presented an analysis of population trends in insectivorous songbirds using data from the BBS. They concluded that p