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 are estimates of the proportional contributions of bearded seal, beluga whale, bowhead whale, and ringed seal to the diets of southern Beaufort Sea polar bears. Fat biopsy samples were collected from polar bears captured or biopsy darted along the north coast of Alaska or on offshore ice during March, April, and May from 2004 to 2016. Fatty acid data of the above four prey species were compiled from online sources (Bromaghin et al. 2015ab, USGS 2021) and one private source that has been used in several polar bear diet studies (Thiemann et al. 2008). Diet composition was estimated from polar bear adipose tissue fatty acid composition data (USGS 2023) using three methods: the original quantitative fatty acid signature analysis model (Iverson et al. 2004, McKinney et al. 2017) and two alternative methods based on recommendations by Bromaghin et al. (2015c, 2016ab, 2017).

These data are estimates of the proportional contributions of bearded seal, beluga whale, bowhead whale, and ringed seal to the diets of southern Beaufort Sea polar bears. Fat biopsy samples were collected from polar bears captured or biopsy darted along the north coast of Alaska or on offshore ice during March, April, and May from 2004 to 2016. Fatty acid data of the above four prey species were compiled from online sources (Bromaghin et al. 2015ab, USGS 2021) and one private source that has been used in several polar bear diet studies (Thiemann et al. 2008). Diet composition was estimated from polar bear adipose tissue fatty acid composition data (USGS 2023) using three methods: the original quantitative fatty acid signature analysis model (Iverson et al. 2004, McKinney et al. 2017) and two alternative methods based on recommendations by Bromaghin et al. (2015c, 2016ab, 2017).

This dataset is one table with data collected and derived from polar bears sampled in Alaska's southern Beaufort Sea during 2015-2019. Data include demographic and morphometric information from each sampled polar bear, gut microbiome diversity indices derived from fecal DNA metabarcoding, and the proportion of prey species detected in individual bear diets derived from quantitative fatty acid analysis (QFASA). The presence of prey items in the diet of polar bears was also assessed using fecal DNA metabarcoding. Note that cetacean data obtained via DNA metabarcoding was not analyzed and is not presented in this data release. Only southern Beaufort Sea population data are included in this USGS data release. All DNA sequence data have been submitted to the NCBI Short Read Archive (accession bioproject ID: PRJNA773176).

This dataset is one table with data collected and derived from polar bears sampled in Alaska's southern Beaufort Sea during 2015-2019. Data include demographic and morphometric information from each sampled polar bear, gut microbiome diversity indices derived from fecal DNA metabarcoding, and the proportion of prey species detected in individual bear diets derived from quantitative fatty acid analysis (QFASA). The presence of prey items in the diet of polar bears was also assessed using fecal DNA metabarcoding. Note that cetacean data obtained via DNA metabarcoding was not analyzed and is not presented in this data release. Only southern Beaufort Sea population data are included in this USGS data release. All DNA sequence data have been submitted to the NCBI Short Read Archive (accession bioproject ID: PRJNA773176).

These data consist of the fatty acid composition (percent of mass) of adipose tissue samples from polar bears in Alaska's southern Beaufort Sea. Fat biopsy samples were collected from polar bears that were either captured or biopsy darted along the north coast of Alaska or on offshore ice during March, April, or May from 2004 to 2016. The data also include an identification code unique to an individual bear, sex, age class, and the date of sample collection.

These data consist of the fatty acid composition (percent of mass) of adipose tissue samples from polar bears in Alaska's southern Beaufort Sea. Fat biopsy samples were collected from polar bears that were either captured or biopsy darted along the north coast of Alaska or on offshore ice during March, April, or May from 2004 to 2016. The data also include an identification code unique to an individual bear, sex, age class, and the date of sample collection.

This dataset is one table with observations of polar bears located during aerial surveys along the coast and barrier islands of the southern Beaufort Seas during fall, 2010-2013. Survey flights were conducted using A-Star B2 and Bell 206 helicopters at an average altitude of 300 feet AGL and an average speed of 50 miles per hour. Survey crews searched for polar bears using coastal and inland transects and over-flights of all coastal barrier islands.

This data set is one table with observations of polar bears located during aerial surveys along the coast and barrier islands of the southern Beaufort Seas during fall, 2010-2013. Survey flights were conducted using A-Star B2 and Bell 206 helicopters at an average altitude of 300 feet AGL and an average speed of 50 miles per hour. Survey crews searched for polar bears using coastal and inland transects and over-flights of all coastal barrier islands.

This data release includes 4 child items with data regarding metabolic rate, body composition, diet, behavior, blood chemistry, stable isotope, tri-axial accelerometer, and GPS locations of polar bears (Ursus maritimus) on land, Western Hudson Bay, Canada, 2019-2022. Child Item 1: "GPS Location Data from Polar Bears (Ursus maritimus) Instrumented on Land, Western Hudson Bay, Canada, 2019-2022" Child Item 2: "Metabolic Rate, Body Composition, and Blood Biochemistry Data from Polar Bears (Ursus maritimus) on Land, Western Hudson Bay, Canada, 2019-2022" Child Item 3: "Tri-axial Accelerometer and Temperature Data from Polar Bears (Ursus maritimus) Instrumented on Land, Western Hudson Bay, Canada, 2019-2022" Child Item 4: "Behavior and Diet Data Derived from Video Camera Collars on Polar Bears (Ursus maritimus) Instrumented on Land, Western Hudson Bay, Canada, 2019-2022"