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Polar bears (Ursus maritimus) are difficult to study because of logistical challenges. Satellite radio collars are an excellent tool for efficiently collecting information on the distribution and habitat use of polar bears because they can be deployed for multiple years. Radio collars can be constructed using materials and devices that result in the collar falling off an animal so that the animal does not retain a non-functional collar indefinitely. However, the performance of "drop-off" materials and devices has been sub-optimal for many years. For example, collar release timer units (RTU), which cause the collar to detach from an animal at a pre-programmed point in time, can fail to function. Similarly, collar...
This study focuses on a 67 attribute lake cover classification scheme covering the Bering Land Bridge area of the Seward Peninsula, Alaska. The GIS dataset consists of 5170 lakes (which were extracted from a 5m resolution ifSAR/orthophoto image) and provides information on lake morphometry, hydrologic connectivity, surface area dynamics, surrounding terrestrial ecotypes, bedfast percentage, and other important conditions. The Seward Peninsula lake habitat study classification system provides lake specific information for a coastal peninsula area that will guide research and aid in the management of the natural environment.
Categories: Data;
Tags: Alaska,
Aquatic Ecosystems,
Bering Land Bridge National Preserve,
Environment,
Fluvial Landforms,
Since 1993 the U.S. Geological Survey (USGS) has worked with the Alaska Department of Transportation and Public Facilities (ADOT&PF) to provide hydraulic assessments of scour for bridges throughout Alaska. As part of this effort, repeat channel cross section surveys, or channel soundings, have been collected at either the upstream or downstream side of bridges on an annual or as needed basis. Streambed and bank elevations are measured using USGS sounding weights and reels, weighted measuring tapes, acoustic Doppler current profilers, multibeam echo sounders and light detection and ranging and are referenced to the datum of as-built plan set to provide context for the streambed elevations in relation to bridge structures....
Categories: Data,
Data Release - Revised;
Tags: ADCP,
Acoustic Doppler Current Profiling,
Alaska,
Bridges,
Discharge/flow,
These were data collected from polar bears from the Southern Beaufort Sea during the spring between 2007 and 2014. Data include individual ID, capture date, sex and age class, whether individuals visited bowhead whale carrion sites, exposure status relative to five pathogens, and concentrations of certain persistent organic pollutants.
These were data collected from polar bears from the Southern Beaufort Sea during the spring between 2013 and 2015. Data include individual identification, demographic characteristics, year, status for the current and prior year regarding use of land, concentrations of stress response and reproductive hormones, blood-based biomarker measures indicative of fasting, body mass index, and body condition. These data were used to assess factors influencing variation in measures of innate immunity, physiological stress, and concentrations in stress-response and reproductive hormones in polar bears.
This data release contains two tables of information on polar bear distributions in the southern Beaufort Sea during spring, from 2001 to 2016. One table provides location (classified into 5 broad regions) of individual bears during the spring. The other table presents the aerial search effort by year and area.
This dataset contains measures of oxygen consumption and stroke frequency from 1 captive subadult female polar bear (166.5 kg) resting in the water (n = 7 sessions) and swimming and diving in a metabolic swim flume with water circulated at approximately 0.6 km/hr during swimming and diving measurements (n = 6 sessions) in September 2017.
This dataset is in five tables with data from ecophysiological studies of free-ranging polar bears of the Southern Beaufort Sea subpopulation. They were equipped with high-resolution activity sensors, body temperature loggers, and GPS satellite-telemetry collars, to compare physiological state and activity of bears during natural behavior with that experienced by bears during helicopter recapture events (n = 14 bears). The data include: rectal temperatures for comparison to temperatures recorded by implanted loggers, levels of blood biochemical markers (n = 50 bears) related to elevated body temperature and stress for testing whether these markers were influenced by the duration of helicopter operations, ambient...
Categories: Data;
Tags: Alaska,
Anatomy and physiology,
Animal response,
Animals/Vertebrates,
Bears,
This dataset is two tables with data collected and derived from polar bears sampled in Alaska’s southern Beaufort Sea during 2008-2019. Collected data includes demographic and morphometric information and derived data includes mercury concentrations in hair samples. Ancillary data includes gut microbiome abundances, diversity indices, calculated body condition, and the proportions of prey species detected in individual bear diets. These data were used to determine whether gut microbiota community richness and diversity were associated with diet-acquired mercury.
This dataset consists of one table with predicted locations of adult female polar bears. Locations were derived by a Continuous Time-Correlated Random Walk (CTCRW) model using satellite tracking radio-collared adult female polar bears captured and instrumented in the southern Beaufort Sea, 1986–2016.
These data are the fatty acid compositions (in percent) of adipose tissue samples collected from polar bears and of blubber samples collected from ringed and bearded seal killed by polar bears in the Chukchi Sea, 2008-2017. The dataset includes sex, age, and age class of the bears that were sampled. The data are provided as percent of each fatty acid identified via nomenclature that describes the structure of each fatty acid.
These data from satellite radio-collared adult female polar bears captured in the southern Beaufort Sea, 1985-2016 were used for testing the regional, seasonal and decadal efficacy of retrospective polar bear resource selection functions (RSF) developed for the Arctic basin and its peripheral seas (see Durner et al. 2009). The data includes the following: 1) a csv file of locations used to build a 99% minimum convex polygon study area; 2) a csv file of locations, that occurred within the study area, and were used to test RSFs; 3) a csv file of locations used to build seasonal kernel utilization distributions (95% and 50% contours) for periods 1985-1995, 1996-2006, and 2007-2016.
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