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Two independent sampling methods were used to collect genetic samples from grizzly bears (Ursus arctos): (i) hair traps—corrals of barbed wire with lure in the center systematically distributed using an 8 x 8 km (1998, 2000) or 7 x 7 km (2004) grid and (ii) bear rubs—naturally occurring trees or other objects that bears rub on fitted with barbed wire (1998–2000, 2004, and 2009–2012). From 1998 to 2000, sampling occurred on 8000 km2 in the northern extent of the Northern Continental Divide Ecosystem (NCDE), whereas systematic and consistent, ecosystem-wide sampling occurred in 2004 and 2009–2012. In total, there were 6160 confirmed grizzly bear detections, leading to the identification of 1115 unique individual genotypes...
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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.
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***This dataset is superseded by Adams, M.J., Pearl, C.A., McCreary, B., Galvan, S.K., and Rowe, J.C., 2017, Oregon Spotted Frog Monitoring at Jack Creek 2015-2016: U.S. Geological Survey data release, https://doi.org/10.5066/F7V40SC6*** This dataset contains information from mark-recapture surveys conducted in 2015 by USGS as part of an ongoing Oregon spotted frog (Rana pretiosa) monitoring effort at Jack Creek, Klamath County, Oregon. Data consist of spotted frog counts aggregated by date, location, life stage, and sex, as well data on environmental conditions at the time of each survey.
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This dataset contains information from mark-recapture and egg mass surveys conducted 2015-2016 by USGS as part of an ongoing Oregon spotted frog (Rana pretiosa) monitoring effort at Jack Creek, Klamath County, Oregon. Data consist of spotted frog counts aggregated by date, location, life stage, and sex, as well as data on environmental conditions at the time each survey.
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***This dataset is superseded by Adams, M.J., Pearl, C.A., McCreary, B., Galvan, S.K., and Rowe, J.C., 2017, Oregon Spotted Frog (Rana pretiosa) Monitoring in the Oregon Cascades 2012-2016: U.S. Geological Survey data release, http://doi.org/10.5066/F7QC01NV*** This dataset contains information from visual encounter surveys conducted between 2012 and 2015 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...
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The current study was designed to provide critical information for resource managers (specifically the Bureau of Ocean Energy Management, henceforth BOEM, and the U.S. Fish and Wildlife Service, henceforth USFWS) about the spatial ecology, population status, and potential population threats to sea otters in Santa Barbara Channel, with particular reference to exposure to manmade structures and sources of oil and natural gas. Our four primary research objectives were: 1. Determine the extent of movements and spatial use patterns by sea otters along the southern California coast 2. Identify important sea otter resting and foraging areas adjacent to manmade structures 3. Assess sea otter distribution, behavior and...
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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.
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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...
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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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A plague (Yersinia pestis) epizootic spread through Gunnison's prairie dogs (Cynomys gunnisoni), and possibly other rodent species, in the Moreno Valley in north-central New Mexico between winter 1984-1985 and autumn 1987. We observed the progress of the epizootic and subsequent population recovery at four prairie dog towns within the valley during this period. At two towns (Midlake and Val Verde) the prairie dogs were marked prior to the epizootic. At two additional towns (Vega and South Entrance) prairie dogs were marked following the epizootic. In 1988, a second epizootic occurred at Vega. One hundred thirty-nine serum samples were collected from prairie dogs and other rodents and 1,750 fleas were collected from...
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Biological soil crusts are an essential part of desert ecosystems throughout the world, as they are important in soil stabilization and soil fertility. Despite their importance, there have been few efforts to examine the population dynamics of the dominant species comprising these crusts or the effect of exotic plant invasions on these dynamics. In this study, we followed changes in lichen and moss cover for 8 years in plots dominated by native grasses or invaded by the exotic annual grass Bromus tectorum and across sites representing a range of land use histories. Our data showed that cover of both lichens and mosses can increase dramatically over short time periods, often going from just above 0% cover to as high...
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Lake Erie Biological Station (LEBS), located in Sandusky, Ohio, is a field station of the USGS Great Lakes Science Center (GLSC). LEBS is the primary federal agency for applied fisheries science excellence in Lake Erie. Since 2004, LEBS has participated in a collaborative, multiagency effort to assess forage fish populations in the western basin of Lake Erie. Assessing the distribution and abundance of both predator and prey (forage) fish species is a cornerstone of ecosystem-based based fishery management, and supports decision making that considers food-web interactions. 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...
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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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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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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: population dynamics, Lake Ontario
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Rainfall variability is a key driver of ecosystem structure and function in grasslands worldwide. Changes in rainfall patterns predicted by global climate models for the central United States are expected to cause lower and increasingly variable soil water availability, which may impact net primary production and plant species composition in native Great Plains grasslands. We experimentally altered the timing and quantity of growing season rainfall inputs by lengthening inter-rainfall dry intervals by 50%, reducing rainfall quantities by 30%, or both, compared to the ambient rainfall regime in a native tallgrass prairie ecosystem in northeastern Kansas. Over three growing seasons, increased rainfall variability...
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These data are .csv files of tagged sea otter re-sighting locations (henceforth, resights) collected in the field using a combination of VHF radio telemetry and direct observation using high powered (80x) telescopes. Sea otters were tracked by shore or boat-based observers from the date of tagging until the time of radio battery failure, the animal’s death, or the end of the project, whichever comes first. The frequency of re-sighting was opportunistic, depending on logistical factors such as coastal access, but generally ranged from daily to weekly. Location coordinates are reported latitude and longitude as well as X and Y coordinates in the projection/datum California Teale-Albers NAD 1927. The file contains...
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These data are .csv files of capture data from tagged sea otters in the Santa Barbara Channel Study. Sea otters were captured using highly specialized techniques employed by a team a rebreather divers and were processed by a shore team and veterinary crew at a mobile vet lab. Overall health assessments and morphometric data were collected, and the otters received colored flipper tags (for visual identification in the field) as well as VHF radio transmitter implants (for locating and "re-sighting" individuals) and time-depth recorder instruments (for archival logging of dive records and core body temperature for individual sea otters). Fields include an individual otter identification number, capture date, general...
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...
We examined the effects of the Zemko Dam removal on the Eightmile River system in Salem, Connecticut, USA. The objective of this research was to quantify spatiotemporal variation in fish community composition in response to small dam removal. We sampled fish abundance over a 6-year period (2005-2010) to quantify changes in fish assemblages prior to dam removal, during drawdown, and for three years following dam removal. Fish population dynamics were examined above the dam, below the dam, and at two reference sites by indicator species analysis, mixed models, non-metric multidimensional scaling, and analysis of similarity. We observed significant shifts in fish relative abundance over time in response to dam removal....


map background search result map search result map Dynamics of plague in a Gunnison's prairie dog colony complex from New Mexico Productivity responses to altered rainfall patterns in a C4-dominated grassland. Soil lichen and moss cover and species richness can be highly dynamic: The effects of invasion by the annual exotic grass Bromus tectorum, precipitation, and temperature on biological soil crusts in SE Utah Long-Term Trends in Mule Deer Pregnancy and Fetal Rates in Colorado Changes in landscape composition influence the decline of a threatened woodland caribou population Matrix composition affects the spatial ecology of a prairie planthopper. Oregon Spotted Frog (Rana pretiosa) Monitoring at Jack Creek 2015 Oregon Spotted Frog (Rana pretiosa) Monitoring in the Oregon Cascades 2012-2015 Lake Ontario Deepwater Sculpin Bottom Trawl Catch and Biological Data, 1996-2016 Data for Southern Sea Otter Range Expansion and Habitat Use in the Santa Barbara Channel Demographics of Sea Otters in the Santa Barbara Channel Movements of Sea Otters in the Santa Barbara Channel Oregon Spotted Frog (Rana pretiosa) Monitoring in the Oregon Cascades Oregon Spotted Frog (Rana pretiosa) Monitoring at Jack Creek 2015-2016 Oregon Spotted Frog (Rana pretiosa) Monitoring in the Oregon Cascades 2012-2016 Lake Erie Fish Community Data, 2013 - 2016 Gulf Watch Alaska, Benthic Monitoring Component: Sea Otter Aerial Survey Data Kenai Fjords National Park, 2002-2016 Productivity responses to altered rainfall patterns in a C4-dominated grassland. Dynamics of plague in a Gunnison's prairie dog colony complex from New Mexico Oregon Spotted Frog (Rana pretiosa) Monitoring at Jack Creek 2015 Oregon Spotted Frog (Rana pretiosa) Monitoring at Jack Creek 2015-2016 Soil lichen and moss cover and species richness can be highly dynamic: The effects of invasion by the annual exotic grass Bromus tectorum, precipitation, and temperature on biological soil crusts in SE Utah Lake Erie Fish Community Data, 2013 - 2016 Gulf Watch Alaska, Benthic Monitoring Component: Sea Otter Aerial Survey Data Kenai Fjords National Park, 2002-2016 Oregon Spotted Frog (Rana pretiosa) Monitoring in the Oregon Cascades 2012-2015 Oregon Spotted Frog (Rana pretiosa) Monitoring in the Oregon Cascades Oregon Spotted Frog (Rana pretiosa) Monitoring in the Oregon Cascades 2012-2016 Data for Southern Sea Otter Range Expansion and Habitat Use in the Santa Barbara Channel Demographics of Sea Otters in the Santa Barbara Channel Movements of Sea Otters in the Santa Barbara Channel Lake Ontario Deepwater Sculpin Bottom Trawl Catch and Biological Data, 1996-2016 Matrix composition affects the spatial ecology of a prairie planthopper. Long-Term Trends in Mule Deer Pregnancy and Fetal Rates in Colorado Changes in landscape composition influence the decline of a threatened woodland caribou population