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This data package includes two folders of data from Pacific Black Brant (Branta bernicla nigricans) during winter and migration periods. One folder has data from brant wintering along the Baja California Peninsula and Sonoran coasts of Mexico. The data include: (1) body mass and morphological measurements from sport hunter harvested brant, and (2) census counts of brant in Bahia de San Quintin, (3) counts for flock age ratio determination, and (4) behavior. The other folder has data from brant tagged with VHF radio transmitters in July 1999 on the Yukon Kuskokwim Delta, Alaska and detected in the following two years during their annual migration. Data include: 1) one table with attributes of the tagged brant, 2)...
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This dataset consists of one table with annual counts from population plots of Black-legged Kittiwakes and Common Murres at two seabird nesting colonies on Gull and Chisik Islands in lower Cook Inlet, Alaska.
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Of the vital rates that determine recruitment, breeding propensity (i.e., the proportion of females that lay at least one egg) and nest success appear to have the greatest influence, but breeding propensity remains poorly studied. The few studies that have been conducted reveal it to be highly variable among years (15–77%), likely in response to environmental conditions (e.g., precipitation and wetland availability), and lower than estimates from other dabbling ducks. Thus, quantifying breeding propensity across the mottled duck range in the WGC and identifying factors responsible for its variation remain high priorities for future investigation. Breeding propensity is also among the most difficult vital rates to...
Snowshoe hare populations fluctuate over a period of several years and are thought to send the cats on migration routes in what’s known as the “travelling wave” theory. In a changing boreal region, scientists want to know where and how lynx move across the landscape to better understand how the larger system is connected.Researchers will build on on-going research in national wildlife refuges by placing satellite tracking collars on cats to better understand the dynamics across the region. Isotypes in the cats’ teeth as well as genetic markers give more clues about lynx movement. This project involves collaboration with local trappers.The project is a collaboration among the University of Alaska Fairbanks, Yukon...
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Climate change vulnerability assessments are commonly used to identify species or populations at risk from global climate change, but few translate impact assessments to climate change adaptation actions. Furthermore, most climate change adaptation efforts emphasize where to implement management actions, whereas timing remains largely overlooked. The rate of modern climate change introduces urgency in evaluating whether delaying conservation actions compromises their efficacy for reaching important conservation targets. We evaluated the importance of multiple climate change adaptation strategies including timing of actions on preventing extinctions for a threatened climate-sensitive species, the Eastern Massasauga...
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A study comparing reintroduction scenarios for the San Francisco gartersnake (Thamnophis sirtalis tetrataenia), an endangered subspecies native to San Mateo County and Santa Cruz County in northern California. Models for snake survival, growth, fecundity, and reproductive status were used to construct a demographic population model. Data are posterior distributions for demographic parameters from Markov Chain Monte Carlo sampling in hierarchical Bayesian models. These data support the following publication: Rose, J.P., Kim, R., Schoening, E.J., Lien, P.C., and Halstead, B.J., 2023. Comparing reintroduction strategies for the endangered San Francisco gartersnake (Thamnophis sirtalis tetrataenia) using demographic...
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Assessing the distribution and abundance of both predator and prey (forage) fish species is a cornerstone of ecosystem-based fishery management and supports decision making that considers food-web interactions. In support of binational Great Lakes fishery management, the objectives of this survey were to: provide estimates of densities of key forage and predator species in the western basin of Lake Erie, to assess seasonal and spatial distributions of fishes in tandem with water quality information, and to assess year class strength. A systematic grid sampling approach with 41 stations was sampled via bottom trawl during June (Spring) and September (Autumn), starting in 2013. This data release adds 2023 data to...
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The imagery and annotations presented here were generated while testing an aerial photographic survey design to improve repeatability, transparency, and estimation of variance for annual population estimates of geese staging at Izembek Lagoon, Alaska. This dataset includes 1) 131,031 .JPG images captured from a small fixed-wing occupied aircraft, usually at an altitude of about 457 m, over Izembek Lagoon; 2) annotations of objects (geese, ducks, and gulls) assigned by an automated algorithm, and 3) manually corrected annotations that were edited by project staff for only those photos automatically identified as containing geese of any species. The photos were captured at predetermined points to systematically sample...
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The American alligator (Alligator mississippiensis) is a species of ecological and economic importance in the southeastern United States. Within South Carolina, alligators are subject to private and public harvest programs, as well as nuisance removal. These management activities can have different impacts across alligator size classes that may not be apparent through widely-used monitoring techniques such as nightlight surveys. We synthesized multiple datasets within an integrated population model (IPM) to estimate size class-specific survival and abundance estimates, that would not be estimable through separate, non-integrated modeling frameworks. The IPM framework included a multistate mark-recapture-recovery...
Snowshoe hare populations fluctuate over a period of several years and are thought to send the cats on migration routes in what’s known as the “travelling wave” theory. In a changing boreal region, scientists want to know where and how lynx move across the landscape to better understand how the larger system is connected.Researchers will build on on-going research in national wildlife refuges by placing satellite tracking collars on cats to better understand the dynamics across the region. Isotypes in the cats’ teeth as well as genetic markers give more clues about lynx movement. This project involves collaboration with local trappers.The project is a collaboration among the University of Alaska Fairbanks, Yukon...
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These data are in two tables relating to fall age ratios (number of juvenile birds : total birds aged) of Black Brant (Branta bernicla nigricans) staging in Izembek Lagoon, Alaska, since 1963. The first table is observation data for the age classes of Black Brant during surveys, and associated survey characteristics. The second table contains model-based estimates of age ratios by year along with Standard Error (SE), and 95% Bayesian credible intervals around estimates.
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This dataset identifies lead (Pb) concentration found in the blood of waterfowl sampled in western and northern Alaska and eastern Russia between 1993 and 2022. Data include age, sex, body measurement, capture location, presence or absence of lead shot on x-rays, and blood lead levels. Because the study took place over a number of years at the same study sites, many of the same birds were sampled in multiple years.
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The Cape Sable Seaside Sparrow (CSSS; Ammospiza maritima mirabilis) is an endangered species that has experienced population declines of more than 60% since the 1990s. The CSSS is restricted in geographic extent to a relatively small area of remaining marl prairie in the southern Florida Everglades and remains in six subpopulation areas (named A-F). There has been over two decades of field research conducted on the CSSS across its six subpopulations, but a statistically robust analysis of the bird’s demographic parameters utilizing all data has yet to be completed. To address this gap, we conducted demographic analysis of the CSSS population using an integrated population model (IPM). The IPM provides a flexible...
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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...
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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This collection includes shell-skeletal remains of Gopherus agassizii from 1980 through 2012 that was collected as part of a monograph covering the desert tortoise populations inside and outside the fenced Desert Tortoise Research Natural Area of California during a period of population decline. The principal objectives of the study were to compare trends in demographic and habitat data inside the protective fence with those outside the fence. Populations and habitat outside the fence were unprotected from recreational vehicle use and sheep grazing. Data for each shell-skeletal remain found on the long-term, 7.77 square kilometers plot, included carcass number, previous number as a live tortoise, date of collection,...
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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 2023. Data from 1978 - 2015 are from U.S. waters of Lake Ontario while data from 2016 - 2023 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.
map background search result map search result map Using light-level geolocators to measure breeding propensity of mottled ducks in the Western Gulf Coast Publication: Delaying conservation actions matters for species vulnerable to climate change Data and Model-Based Estimates from Black Brant (Branta bernicla nigricans) Fall Age Ratio Surveys at Izembek Lagoon, Alaska Final Report: Using light-level geolocators to measure breeding propensity of mottled ducks in the Western Gulf Coast Aerial Photo Imagery from Fall Waterfowl Surveys, Izembek Lagoon, Alaska, 2017-2019 American alligator demographic and harvest data from Georgetown County, South Carolina, 1979–2017 Waterfowl Lead Exposure Data in Alaska and Russia Data from Black Brant (Branta bernicla nigricans) Overwintering in Three Lagoons Along the Baja California Peninsula, Mexico Demographic Parameter Estimates for San Francisco Gartersnakes (Thamnophis sirtalis tetrataenia) for Fitting an Integral Projection Model USGS Desert Tortoise Shell-skeletal Remains Collection Lake Ontario April Prey Fish Bottom Trawl Survey, 1978-2023 Model code to build and run an integrated population model for the endangered Cape Sable Seaside Sparrow Bottom Trawl Catch Alewife Densities and Ages in Lakes Michigan and Huron Lake Erie Fish Community Data, 2013-2023 Predation of Common Murre Eggs at Two Seabird Colonies in Lower Cook Inlet, Alaska Nesting Productivity of Black-Legged Kittiwakes and Common Murres at Two Seabird Colonies in Lower Cook Inlet, Alaska Population Plots at Two Seabird Colonies in Lower Cook Inlet, Alaska USGS Desert Tortoise Shell-skeletal Remains Collection Model code to build and run an integrated population model for the endangered Cape Sable Seaside Sparrow Aerial Photo Imagery from Fall Waterfowl Surveys, Izembek Lagoon, Alaska, 2017-2019 American alligator demographic and harvest data from Georgetown County, South Carolina, 1979–2017 Predation of Common Murre Eggs at Two Seabird Colonies in Lower Cook Inlet, Alaska Nesting Productivity of Black-Legged Kittiwakes and Common Murres at Two Seabird Colonies in Lower Cook Inlet, Alaska Population Plots at Two Seabird Colonies in Lower Cook Inlet, Alaska Lake Erie Fish Community Data, 2013-2023 Lake Ontario April Prey Fish Bottom Trawl Survey, 1978-2023 Data from Black Brant (Branta bernicla nigricans) Overwintering in Three Lagoons Along the Baja California Peninsula, Mexico Bottom Trawl Catch Alewife Densities and Ages in Lakes Michigan and Huron Using light-level geolocators to measure breeding propensity of mottled ducks in the Western Gulf Coast Final Report: Using light-level geolocators to measure breeding propensity of mottled ducks in the Western Gulf Coast Publication: Delaying conservation actions matters for species vulnerable to climate change Waterfowl Lead Exposure Data in Alaska and Russia