Filters: Tags: Population Dynamics (X)
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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...
Categories: Data,
Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2017,
Anas fulvigula,
BIOSPHERE,
Conservation NGOs,
Data Acquisition and Development,
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...
Categories: Data;
Tags: Academics & scientific researchers,
Conservation NGOs,
FOOD-WEB DYNAMICS,
FOOD-WEB DYNAMICS,
Federal resource managers,
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...
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...
Categories: Data;
Tags: California,
San Mateo County,
USGS Science Data Catalog (SDC),
Wildlife Biology,
biota,
In Texas, the USFWS is currently reviewing 11 mussel species for ESA protection and several of these species (e.g., Cyclonaias petrina, Texas Pimpleback, and Lampsilis bracteata, Texas Fatmucket) have been the primary focus of controlled propagation by several federal hatcheries. To date, information on genetic diversity within and across known populations for these species is incomplete and so the justification for their controlled propagation is unclear, and a genetic management plan to guide propagation activities does not exist. These unknowns raise serious questions about whether any of the 11 proposed species are truly in need of and would benefit from controlled propagation. The overall goal of this project...
Categories: Data,
Project;
Tags: ANIMALS/INVERTEBRATES,
BIOLOGICAL CLASSIFICATION,
BIOSPHERE,
BIVALVES,
EARTH SCIENCE,
Conclusions: Habitat changes resulting from timber harvest have altered the predator–prey balance leading to asymmetric predation affecting the survivial rates of endangered mountain caribou Thresholds/Learnings: As young forest stands increase in proportion to old forests, caribou population densities and survival rates decline as they become increasingly vulnerable to predation and extripation. Synopsis: Timber harvesting in areas of Mountain Caribou habitat have created landscapes of early seral forests. Such habitat changes have altered the predator–prey balance resulting in asymmetric predation in which predators are maintained by alternative prey (i.e. apparent competition). This study estimates survival...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: British Columbia,
Caribou,
Natural cover amount,
Predation,
Woodland Caribou,
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 2019 data to...
This dataset contains information from visual encounter surveys conducted between 2012 and 2016 by USGS as part of an ongoing Oregon spotted frog (Rana pretiosa) monitoring effort in the Oregon Cascade Mountain Range. We surveyed 91 sites using a rotating frame design in the Klamath and Deschutes Basins, Oregon, which encompass most of the species' core extant range. Data consist of spotted frog counts aggregated by date, location, and life stage, as well as data on environmental conditions at the time of each survey.
This data set provides a table of length, weight, sex, and estimated fecundity of Silver Chub Macrhybopsis storeriana in western Lake Erie from 1979 through 1987. These data are potentially useful to those studying recovery and restoration of Silver Chub in Lake Erie. These data were collected as part of routine trawl surveys in western Lake Erie. Other data associated with these data can be found in the Great Lakes Research Vessel Operations 1958-2018. (ver. 3.0, April 2019). A drawn map, originally packaged alongside the hard copy data sheets, is included in this data release. This map guides users in identifying specific locations of capture. Due to the legacy nature of these data, location data is estimated...
Categories: Data;
Types: Citation;
Tags: Lake Erie,
USGS Science Data Catalog (SDC),
biota,
endangered species,
native species,
This dataset contains information from surveys conducted 2004-2015 by USGS as part of a long-term amphibian monitoring effort in the Willamette Valley, Oregon. Data consist of site, survey, habitat, and species detection covariates.
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 2020 data to...
The dataset includes three separate excel spreadsheets which provides waterbird (and predator) observations within individual survey units during the May 2019 breeding waterbird survey of south San Francisco Bay (2019WaterbirdSurveyFullData.xlsx), the total number of American avocets, black-necked stilts, and Forster's terns within each pond unit surveyed during the May 2019 survey (2019WaterbirdSurveyPondModel.xlsx), and the annual total number of nests for American avocets, black-necked stilts, and Forster's terns in south San Francisco between 2005 and 2019 (SouthBayWaterbirdNests2005-2019.xlsx). These data support the following publication: Hartman, C.A., Ackerman, J.T., Schacter, C.R., Herzog, M.P., Tarjan,...
Categories: Data;
Tags: San Francisco Bay,
USGS Science Data Catalog (SDC),
Wildlife Biology,
biota,
birds,
Desert spring wetlands host many endemic species that require aquatic habitat and are isolated by the surrounding xeric terrestrial habitat. The Dixie Valley Toad (Anaxyrus williamsi) is a recently described anuran species endemic to desert spring wetlands in the Dixie Valley, Churchill County, Nevada, USA. Given this species was only recently recognized as distinct from Anaxyrus boreas, little is known about its ecology and habitat requirements. These data represent the results of surveys for Dixie Valley Toads conducted from April 2018 to May 2021 in Churchill County, Nevada, USA and associated covariates from surveys and study sites. The potential wetland habitat for the Dixie Valley Toad was divided into 20...
Sympatric populations of Cophosaurus texanus and Callisaurus draconoides were periodically sampled from March 1973 through April 1974 at Burro Creek, Mohave County, Arizona. Callisaurus were also sampled at Rock Valley, Nye County, Nevada. Sex ratios were skewed in favor of males in the adult Cophosaurus but were equal in both adult populations of Callisaurus. Both species became sexually mature as yearlings. Mean clutch sizes were 3.55 (+/- 0.83) for Cophosaurus, and 4.25 (+/- 1.08) and 5.07 (+/- 1.33) for Callisaurus at Burro Creek and Rock Valley respectively. Evidence of multiple clutches was exhibited by both species. Egg weight/body weight ratios for both species and clutch weight/body weight ratios for Cophosaurus...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Nevada,
Reptilia,
USA,
Western North American Naturalist,
animals,
These data were compiled as part of an ecological study of Sonora Mud Turtles and their interaction with non-native turtles at Montezuma Well in Yavapai County, Arizona. The data consist of observations and measurements of individual turtles captured during the study, and support analyses of population size and trends, general condition and health of the turtles, and female reproduction. Principal investigators for the study were Phil Rosen (1983 data), Matthew Malone and Steve Garber (1999 data) and Jeff Lovich and Charles Drost (data from 2007 through 2015). This dataset provides detailed capture data, measurements, and female reproductive status for the Sonora Mud Turtle population at Montezuma Well, which should...
Conservationists have proposed methods for adapting to climate change that assume species distributions are primarily explained by climate variables. The key idea is to use the understanding of species-climate relationships to map corridors and to identify regions of faunal stability or high species turnover. An alternative approach is to adopt an evolutionary timescale and ask ultimately what factors control total diversity, so that over the long run the major drivers of total species richness can be protected. Within a single climatic region, the temperate area encompassing all of the Northeastern U.S. and Maritime Canada, we hypothesized that geologic factors may take precedence over climate in explaining diversity...
Categories: Publication;
Types: Citation;
Tags: *Biodiversity,
*Climate Change,
*Geological Phenomena,
Animals,
Population Dynamics
Data comprise 6632 observations of individually banded Painted Buntings, captured and observed from 1999-2016 at 40 study locations on the southeastern Atlantic Coast (NC, SC, GA and FL, US).
Categories: Data;
Tags: Ecology,
Migratory Birds,
Painted Bunting,
Population Dynamics,
Southeastern Atlantic Coast,
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 populations 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...
Categories: Data;
Types: Citation;
Tags: Antilocapra americana,
Arizona,
Climatology,
Drought,
Drought, Fire and Extreme Weather,
This dataset contains the physical collection information (e.g., sample location, date, gear type) and microsatellite DNA genotype of egg and larval Lake Sturgeon collected in the St. Clair and Detroit rivers in 2015 and 2016. Individuals were genotyped for 18 microsatellite loci (13 disomic and 5 polysomic). Alleles (base pair sizes) were recorded as presence absence scores (1:present, 2:absent, 0:missing data) for all previously observed alleles. Thus individual genotypes were recorded as pseudo diploid dominant phenotypes resulting in individual vectors of length n=205 for each genotyped egg or larval individual.
Categories: Data;
Tags: Acipenser,
Acipenser fulvescens,
Acipenseridae,
Anthropogenic,
Anthropogenic Rock,
These data include egg mass counts and adult capture-mark-recapture histories for Foothill Yellow-legged frogs (Rana boylii) at two streams in northern California. Data were collected from the South Fork Eel River and its tributary, Fox Creek, from 1993-2019. Data from Hurdygurdy Creek were collected from 2002-2008. This code and data support the following publication: Rose, JP, Kupferberg, SJ, Wheeler, CA, Kleeman, PM, and Halstead BJ. 2021. Estimating the survival of unobservable life stages for a declining frog with a complex life history. Ecosphere. 12(2):e03381.
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