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Climate often drives ungulate population dynamics, and as climates change, some areas may become unsuitable for species persistence. Unraveling the relationships between climate and population dynamics, and projecting them across time, advances ecological understanding that informs and steers sustainable conservation for species. Using pronghorn (Antilocapra americana) as an ecological model, we used a Bayesian approach to analyze long-term population, precipitation, and temperature data from 18 subpopulations in the southwestern United States. We determined which long-term (12 and 24 months) or short-term (gestation trimester and lactation period) climatic conditions best predicted annual rate of population growth...
Abstract (from https://www.ncbi.nlm.nih.gov/pubmed/26990459): There is intense interest in basic and applied ecology about the effect of global change on current and future species distributions. Projections based on widely used static modeling methods implicitly assume that species are in equilibrium with the environment and that detection during surveys is perfect. We used multiseason correlated detection occupancy models, which avoid these assumptions, to relate climate data to distributional shifts of Louisiana Waterthrush in the North American Breeding Bird Survey (BBS) data. We summarized these shifts with indices of range size and position and compared them to the same indices obtained using more basic modeling...
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These data were compiled to investigate the demographic and phylogeographic of Carex specuicola. Objectives of our study were to understand the demographic and dispersal history of Carex specuicola across hanging gardens, the hybridization history between Carex specuicola and Carex utahensis, and the population structure of Carex specuicola across its distribution. The data release consists of three tab delimited text files that may be used to infer population structure and diversity (CASP.stru), relationships among sampling localities Carex.phylip), or genetic diversity statistics and demographic history (Carex.snps.vcf). These data represent genetic variation on an individual (.stru and .vcf) or sampling locality...
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The Western Gulf Coast (WGC) is home to approximately 90% of the worldwide population of mottled ducks (Anas fulvigula), a non-migratory species that must satisfy its annual cycle needs within a small geographic range. Available population data suggest the WGC mottled duck population has experienced a slight to moderate decline across its range since 1985 (Gulf Coast Joint Venture [GCJV] Mottled Duck Working Group, Unpublished report). Because of its population status and reliance on a restricted geography, the mottled duck has been identified as a focal species for the U.S. Fish and Wildlife Service, a priority species in Texas and Louisiana Comprehensive Wildlife Conservation Plans, and the subject of targeted...
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Synopsis: To date, there is a lack of well-controlled field experiments that disentangle the effects of the intervening matrix from other landscape variables (e.g., patch geography or quality) that might influence animal dispersal among patches. We performed a field experiment to investigate how the movement of a delphacid planthopper (Prokelisia crocea) among discrete patches of prairie cordgrass (Spartina pectinata) is affected by the composition of the matrix (mudflat, native nonhost grasses, and the introduced grass smooth brome [Bromus inermis]). Within each matrix type, marked planthoppers were released onto experimental cordgrass patches that were made identical in size, isolation, and host plant quality....
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In 2014, the USGS Lake Erie Biological Station participated in the Coordinated Science and Monitoring Initiative (CMSI) program, a program founded by the U.S. Environmental Protection Agency (EPA) and Environment Canada in the 1990s as a means to focus collaborative research attention on one of the five Great Lakes each year (on a rotating schedule) as a means to increase scientific knowledge for Great Lakes restoration. The Lake Erie survey examined the food web across a nearshore to offshore gradient, matching the sampling design the preceding USGS studies of the other four Great Lakes (2010-2013). We sampled all trophic levels in all three lake basins across multiple seasons in order to determine nutrient availability...
The cycles of the key nutrient elements nitrogen (N) and phosphorus (P) have been massively altered by anthropogenic activities. Thus, it is essential to understand how photosynthetic production across diverse ecosystems is, or is not, limited by N and P. Via a large-scale meta-analysis of experimental enrichments, we show that P limitation is equally strong across these major habitats and that N and P limitation are equivalent within both terrestrial and freshwater systems. Furthermore, simultaneous N and P enrichment produces strongly positive synergistic responses in all three environments. Thus, contrary to some prevailing paradigms, freshwater, marine and terrestrial ecosystems are surprisingly similar in terms...
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Deepwater Sculpin are important in oligotrophic lakes as one of the few fishes that use deep profundal habitats and link invertebrates in those habitats to piscivores. In Lake Ontario the species was once abundant, however drastic declines in the mid-1900s led some to suggest the species had been extirpated and ultimately led Canadian and U.S. agencies to elevate the species’ conservation status in the 1990s. Following multiple decades of annual surveys with no captures, Deepwater Sculpin were first caught in low numbers in 1996 and by the early 2000s there were indications of population recovery. These data sets were used to update the status of Lake Ontario Deepwater Sculpin through 2016 to inform resource management...
Categories: Data; Types: Citation; Tags: Lake Ontario, biota, population dynamics
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Mule deer (Odocoileus hemionus) fawn:doe (f:d) ratios in December have declined by 0.015 fawns/doe/year from 1972 through 1995 in Colorado, USA. To determine whether lower pregnancy or fetal production was the cause of low December f:d ratios, we estimated mule deer pregnancy rates in the Poudre River drainage during January 1998 and pregnancy and fetal rates on the Uncompahgre Plateau during February 1999. Twenty-seven (93.1%) of 29 yearling and adult does in the Poudre River drainage were detected pregnant with pregnancy-specific protein-B (PSPB). This proportion did not differ (P > 0.2) from the proportion of yearling and adult does that were pregnant when collected by various methods in previous studies in Colorado....
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The Great Lakes Research Vessel Operations data release is taken from the Research Vessel Catch (RVCAT) database curated at the Great Lakes Science Center (GLSC). RVCAT has been used as the primary data collection tool aboard the GLSC’s research vessel operations. Content: The data set has been collected on various vessel operations on all the Great Lakes and select connecting waterways between the years 1958-2018. Data collection begins in early spring and ends in late fall. Each vessel operation was completed for a specific purpose, or target mission, which are enumerated in this data set. In addition to vessel operations data, RVCAT collects trawl and gillnet catch data, sample information of fish species caught,...
Types: Citation; Tags: Alewife, Bathythermograph, Benthos, Bloater, Cisco, All tags...
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This dataset includes data on the growth, fecundity, and survival of Giant Gartersnakes (Thamnophis gigas) in the Sacramento Valley of California from 1995-2017. These data support the following publication: Rose, J.P., Ersan, J.S., Wylie, G.D., Casazza, M.L. and Halstead, B.J., 2019. Demographic factors affecting population growth in giant gartersnakes. The Journal of Wildlife Management, 83(7), pp.1540-1551.
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These data are multi-state capture histories of 273 individual San Francisco gartersnakes collected at a site before and after a portion of the site was burned. Data collection began in 2008 and continued until 2013, and the prescribed fire was applied in the fall of 2010. These data support the following paper: Halstead, B. J., Thompson, M. E., Amarello, M. , Smith, J. J., Wylie, G. D., Routman, E. J. and Casazza, M. L. (2018), Effects of prescribed fire on San Francisco gartersnake survival and movement. Jour. Wild. Mgmt.. . doi:10.1002/jwmg.21585
Most populations of migrant shorebirds around the world are in serious decline, suggesting that vital condition-dependent rates such as fecundity and annual survival are being affected globally. A striking example is the red knot (Calidris canutus rufa) population wintering in Tierra del Fuego, which undertakes marathon 30,000 km hemispheric migrations annually. In spring, migrant birds forage voraciously on horseshoe crab eggs in Delaware Bay in the eastern USA before departing to breed in Arctic polar deserts. From 1997 to 2002 an increasing proportion of knots failed to reach threshold departure masses of 180-200 g, possibly because of later arrival in the Bay and food shortage from concurrent over-harvesting...
This project will engage researchers from the University of Idaho to assist with a set of analysis tasks that will improve understanding of seabird population dynamics and environmental drivers at a regional scale based on prior survey efforts that have been focused at a colony scale. Specifically, we envision the development of a population model for a couple of index species like murres and kittiwakes, including evaluation of spatial clustering of populations that co-vary, in order to: 1) asses implications of covariates with identified mechanisms and appropriate temporal (pre-breeding condition, summer, rearing, overwinter survival, etc.) and spatial scales; 2) evaluate the feasibility of combining seabirds into...
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This data release provides catch-per-unit-effort (CPUE) data by age-class for alewife (Alosa pseudoharengus) based on bottom trawl surveys from Lake Michigan (1973-2022) or Lake Huron (1976-2004). These data are associated with a study that sought to evaluate whether alewife populations across the Great Lakes are synchronous in their time series.
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These data are is part of the Gulf Watch Alaska (GWA) long term monitoring program, nearshore monitoring component. Specifically, these data describe sea otter (Enhydra lutris) aerial survey observations from the waters around Kenai Fjords National Park between 2002 and 2016. Sea otters are a keystone predator, well known for structuring the nearshore marine ecosystem through their consumption of invertebrate prey. The dataset consists of 3 comma delimited files exported from Microsoft Excel. The data consists of 1. Strip transect counts, 2. Intensive Search Unit (ISU) counts, and 3. Transect coordinates. For each aerial survey, a pilot flew an airplane at an altitude of 91m over pre-determined transects while an...
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Data include population information of eastern screech owl (Megascops asio, formerly Otus asio) populations in four counties of northern Ohio. Researchers recorded adult and chick color phases, eggs laid, brood size and location.
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This data set represents a preliminary attempt to define distinct areas of Sage-grouse occupation in North America. The 'boundaries' for subpopulations are not actually boundaries, but lines meant to encircle a specific group of leks. The difference may seem trivial, but it is significant. We did not establish an area associated with each population or subpopulation, and consequently we did not evaluate the associated habitat and/or landscape. This type of analysis would have required a specific assessment of the habitat within and between each of the identified populations and subpopulations. The descriptions of subpopulations are clearly a preliminary attempt to define distinct areas of occupation.
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This data release includes Lake Ontario prey fish data including species captured, relative abundance, spatial distribution, size structure, and age data from the April or spring prey fish bottom trawl survey, 1978 through 2022. Data from 1978 - 2015 are from U.S. waters of Lake Ontario while data from 2016 - 2022 include both U.S. and Canadian waters of Lake Ontario. Details about the vessel and gear descriptions, sampling protocols, and catch processing protocols are provided in the associated metadata. Portions of this data release follows the data model of the USGS Great Lakes Science Center Research Vessel Catalog (RVCAT). The trawl data included in this data release are a subset of the larger RVCAT data base....


map background search result map search result map Long-Term Trends in Mule Deer Pregnancy and Fetal Rates in Colorado Matrix composition affects the spatial ecology of a prairie planthopper. Great Lakes Research Vessel Operations 1958-2018. (ver. 3.0, April 2019) Lake Ontario Deepwater Sculpin Bottom Trawl Catch and Biological Data, 1996-2016 Coastal California San Francisco Gartersnake Capture-Mark-Recapture Data (2008-2013) Lake Erie Collaborative Science and Monitoring Initiative 2014 Gulf Watch Alaska, Benthic Monitoring Component: Sea Otter Aerial Survey Data Kenai Fjords National Park, 2002-2016 Impact of Drought on Southwestern Pronghorn Population Trends and Predicted Trajectories Predictor Model Bear capture recapture sampling in Glacier National Park, Montana, 2004 Long-term monitoring data from eastern screech owl populations in northern Ohio, 1944-1971 Data files Final Report: Using light-level geolocators to measure breeding propensity of mottled ducks in the Western Gulf Coast Sage-grouse Subpopulations in North America Carex specuicola genomic data for the southern Colorado Plateau Desert Lake Ontario April Prey Fish Bottom Trawl Survey, 1978-2022 Bottom Trawl Catch Alewife Densities and Ages in Lakes Michigan and Huron Coastal California San Francisco Gartersnake Capture-Mark-Recapture Data (2008-2013) Long-term monitoring data from eastern screech owl populations in northern Ohio, 1944-1971 Gulf Watch Alaska, Benthic Monitoring Component: Sea Otter Aerial Survey Data Kenai Fjords National Park, 2002-2016 Bear capture recapture sampling in Glacier National Park, Montana, 2004 Carex specuicola genomic data for the southern Colorado Plateau Desert Lake Ontario April Prey Fish Bottom Trawl Survey, 1978-2022 Lake Ontario Deepwater Sculpin Bottom Trawl Catch and Biological Data, 1996-2016 Data files Lake Erie Collaborative Science and Monitoring Initiative 2014 Matrix composition affects the spatial ecology of a prairie planthopper. Long-Term Trends in Mule Deer Pregnancy and Fetal Rates in Colorado Bottom Trawl Catch Alewife Densities and Ages in Lakes Michigan and Huron Final Report: Using light-level geolocators to measure breeding propensity of mottled ducks in the Western Gulf Coast Great Lakes Research Vessel Operations 1958-2018. (ver. 3.0, April 2019) Impact of Drought on Southwestern Pronghorn Population Trends and Predicted Trajectories Predictor Model Sage-grouse Subpopulations in North America