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This dataset contains the growth index from annual growth bands in the shells of two bivalve clam species (Astarte borealis and Liocyma fluctuosa) captured in the Chukchi Sea, Alaska. The growth index is based on a measurement of the annual growth increment width that has been detrended for age-related differences in growth.
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,
This study focuses on the development of a 20 attribute lake cover classification scheme for the Fish Creek Watershed (FCW), which is located in the National Petroleum Reserve-Alaska (NPR-A). The GIS dataset consists of 4,362 lakes (which were extracted from a 5m resolution IfSAR/orthophoto image) covering 18% of the 4,900 km2 FCW and provides information on lake morphometry, hydrologic connectivity, surface area dynamics, surrounding terrestrial ecotypes, and other important aquatic conditions. The FCW lake cover classification scheme provides lake specific information for an arctic watershed that will guide research and aid in the management of the natural and human-modified environment.
Categories: Data;
Tags: Alaska,
Aquatic Ecosystems,
Environment,
Fluvial Landforms,
Fluvial morphology,
These are data collected from polar bears from the southern Beaufort Seas during the spring and fall between 2004 and 2011. Data include individual ID, sex and age class, presence of dependent young, season of sample collection, total mercury concentration derived from a hair sample, estimate of annual diet proportion, and indices of body condition.
This data set contains a single table of descriptions of benthic samples collected in 1998 at Nelson and Izembek lagoons, Alaska. This includes: the weight of the sample, the species or species group of benthic animals (also vegetation) and their number, size and weight, and the amount of sand and gravel. These data provide a basis for additional studies that includes sampling of the benthos in Nelson and/or Izembek lagoons. These data are important as historic information useful in examining long-term changes in the lagoons in light of changing climate.
Categories: Data;
Tags: Alaska,
Animals/Invertebrates,
Aquatic Biology,
Arthropods,
Benthic invertebrates,
These were data collected from polar bears from the southern Beaufort Sea during the spring between 2004 and 2016. Data include individual bear identification, age and sex class, capture date, capture year, open water season lengths, melt season length, and diet composition (expressed as a percentage of prey species). These data were used to determine whether polar bear diets have recently changed or remained stable over time.
These data were part of a pilot tracking study of three adult female caribou from the Fortymile Herd in Alaska. The dataset is comprised of two comma separated values (.csv) files. Data includes: 1) processed (i.e., erroneous locations removed) GPS locations for caribou, received once per hour for 6 months (October 1998 to April 1999), and 2) spatial, temporal, and biological attributes of three female caribou tracked during the study.
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.
This data package contains 3 tables presenting site selection information, basin characteristics, subsidy to streamflow from glacier mass loss data, and other streamflow statistics for selected streamgages in Alaska that were used to evaluate the influence of glacier mass loss on streamflow in Alaska and conterminous basins in Canada. The first ("site_selection_outcomes.csv") contains streamgage identification and site selection or omission details for 728 streamgages. The second ("streamflow_statistics_eligible_gages.csv") includes observed mean annual streamflow for the period of record through September 30, 2022, observed or estimated mean annual streamflow for the period 2000-2019, and associated period of record...
Available here are tracking data of Caribou, a terrestrial mammal that ranges between the Alaska and Canada. These data were collected from animals marked in interior and northern Alaska to understand seasonal movement patterns and the effects of fire regime on the movements. USGS Alaska Science Center scientists collect data from wildlife tracking devices to: determine locations of animals throughout their annual cycles, understand patterns of habitat use, quantify time spent on various behaviors, and identify geographic areas repeatedly used by wildlife that may indicate sites of importance to species and populations. Tracking data from other wildlife species can be found at: https://doi.org/10.5066/P9VYSWEH.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Alaska,
Alaska Range,
Animal tracking,
Animals/Vertebrates,
Biota,
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.
These data are in one table with age and sex composition counts of groups of walruses on ice floes in the northern Bering and Chukchi Seas. Counts were collected by visual observations from boats.
This dataset includes 15-minute interval data on stream temperature from low-order streams and main-stem rivers in the Noatak and Kobuk River valleys in Northwestern Alaska, collected during the summer months. The water temperatures were determined using a HOBO Water Temp Pro v2 (Onset Computer Corporation, Bourne, MA, USA)with ±0.2 °C accuracy. Sensors were place in several locations within each stream as well as in the main river below the tributary junction in order to assess stream thermal state.
This dataset is one table with demographic, morphometric, and blood analyte measurements from whole blood and serum samples taken from a subset of polar bears sampled in Alaska's southern Beaufort Sea during 1989-2012. The measured blood analytes include: blood urea nitrogen, creatinine, glucose, total protein, hemoglobin, red blood cell count, packed cell volume, and hemoglobin A1c (HbA1c).
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.
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