These are geospatial data that characterize the distribution of polar bear denning habitat on the coastal plain of northern Alaska between the Colville River and the Alaska/Canada border. One dataset is included in this data package, it is vector geospatial data of putative denning habitat. The vector data are provided in both ESRI shapefile and Keyhole Markup Language (KML) formats. Den habitat is defined as abrupt landscape features (e.g., coastal and riverbanks, lake shores) that are likely to accumulate snow to a depth sufficient for polar bears to build a maternal den (i.e., > 1 meter deep).

These are geospatial data that characterize the distribution of polar bear denning habitat on the National Petroleum Reserve–Alaska (NPR-A). Two datasets are included in this data package, they are both vector geospatial datasets of putative denning habitat (one set each for the western and eastern portion of the NPR-A). Each vector dataset is provided in both ESRI shapefile and Keyhole Markup Language (KML) formats. Denning habitat was estimated from computer interrogation of digital terrain models (DTM) derived from Interferometric Synthetic Aperture Radar (IfSAR) imagery collected by sensors mounted on fix-wing aircraft. Den habitat is defined as abrupt landscape features (e.g., coastal and riverbanks, lake shores) that are likely to accumulate snow to a depth sufficient for polar bears to build a maternal den (i.e., > 1 meter deep).

This data package includes 3 child items with mapping data of polar bear den habitat on the Arctic Coastal Plain of Alaska. Child Item 1: "Data Used to Compare Photo-Interpreted and IfSAR-Derived Maps of Polar Bear Denning Habitat for the 1002 Area of the Arctic National Wildlife Refuge, Alaska, 2006-2016" Child Item 2: "Polar Bear Maternal Den Habitat on the Coastal Plain of Northern Alaska Between the Colville River and the Alaska/Canada border" Child Item 3: "Mapping Data of Polar Bear Maternal Den Habitat, National Petroleum Reserve–Alaska (NPR-A)"

This data package includes 3 child items with mapping data of polar bear den habitat on the Arctic Coastal Plain of Alaska. Child Item 1: "Data Used to Compare Photo-Interpreted and IfSAR-Derived Maps of Polar Bear Denning Habitat for the 1002 Area of the Arctic National Wildlife Refuge, Alaska, 2006-2016" Child Item 2: "Polar Bear Maternal Den Habitat on the Coastal Plain of Northern Alaska Between the Colville River and the Alaska/Canada border" Child Item 3: "Mapping Data of Polar Bear Maternal Den Habitat, National Petroleum Reserve–Alaska (NPR-A)"

This data reports on the approximate locations and methods of discovery of 530 polar bear (Ursus maritimus) maternal dens observed in the Beaufort and Chukchi seas and neighboring areas between 1910 and 2018, and archived partly by the U.S. Geological Survey, Alaska Science Center, and partly by the U.S. Fish and Wildlife Service, Marine Mammals Management, in Anchorage, Alaska. Data fields include a unique and permanent USGS identifier for each record, the year when the adult would have been expected to depart the den with young, an index of whether the maternal den was confirmed or probable, coordinates of the den, substrate that each den occurred on, the agency source of each record, method of discovery of each den, method used to determine the position of each den, and estimated position uncertainty. Data were collected through standardized VHF aircraft surveys and satellite radio telemetry, field research activities in polar bear habitat, and anecdotal reports from other government agencies, coastal residents, and industry personnel. The polar bear maternal den records presented here supersede an earlier version of these data (Durner and others, 2010)

These are geospatial data that characterize the distribution of polar bear denning habitat in the 1002 Area of the Arctic National Wildlife Refuge, Alaska. They were generated to compare the efficacy of two different techniques for identifying areas with suitable den habitat: (1) from a previously published study (Durner et al., 2006) that used manual interpretation of aerial photos and (2) from computer interrogation of interferometric synthetic aperture radar (IfSAR) digital terrain models. Two datasets are included in this data package, they are both vector geospatial datasets of putative denning habitat (one dataset each for the manual photo interpretation data and the computer interpreted IfSAR data). Additionally included are: vector data used for sampling and metadata describing the IfSAR-derived digital terrain model (DTM) tiles used to generate the shapefiles. The IfSAR DTM are available for purchase through Intermap Technologies, Inc. All vector data are provided in both ESRI shapefile and Keyhole Markup Language (KML) formats.

These are geospatial data that characterize the distribution of polar bear denning habitat in the 1002 Area of the Arctic National Wildlife Refuge, Alaska. They were generated to compare the efficacy of two different techniques for identifying areas with suitable den habitat: (1) from a previously published study (Durner et al., 2006) that used manual interpretation of aerial photos and (2) from computer interrogation of interferometric synthetic aperture radar (IfSAR) digital terrain models. Two datasets are included in this data package, they are both vector geospatial datasets of putative denning habitat (one dataset each for the manual photo interpretation data and the computer interpreted IfSAR data). Additionally included are: vector data used for sampling and metadata describing the IfSAR-derived digital terrain model (DTM) tiles used to generate the shapefiles. The IfSAR DTM are available for purchase through Intermap Technologies, Inc. All vector data are provided in both ESRI shapefile and Keyhole Markup Language (KML) formats.

These data represent estimates of den entrance and exit dates for female polar bears in the southern Beaufort and Chukchi Seas based on temperature sensor data obtained from satellite collars. An algorithm described in Olson et al. (2017) was used to determine whether the female entered a den and further analyses using temperature data as described in Olson et al. (2017) were used to assess den entry and emergence dates. The algorithm used identified the denning period as that during which collar temperature remained consistently above a temperature threshold. As such, users of these data should be aware that bear behavior can affect den entrance and exit date. If a bear moves in and out of a den frequently, the algorithm identifies that bear as not denning. Den substrate was determined by examining satellite locations from collars during the identified denning period and classify dens as occurring on landfast ice, pack ice, or land. This data set also includes direct observations of females post-den emergence to ascertain whether or not she was accompanied by cubs as an indicator of reproductive success. The den IDs provided in this data set correspond with those identified in the USGS den catalog (Durner 2010, Durner et al 2020) additional information about the dens in this data set may be found in the catalog.

These data represent estimates of den entrance and exit dates for female polar bears in the southern Beaufort and Chukchi Seas based on temperature sensor data obtained from satellite collars. An algorithm described in Olson et al. (2017) was used to determine whether the female entered a den and further analyses using temperature data as described in Olson et al. (2017) were used to assess den entry and emergence dates. The algorithm used identified the denning period as that during which collar temperature remained consistently above a temperature threshold. As such, users of these data should be aware that bear behavior can affect den entrance and exit date. If a bear moves in and out of a den frequently, the algorithm identifies that bear as not denning. Den substrate was determined by examining satellite locations from collars during the identified denning period and classify dens as occurring on landfast ice, pack ice, or land. This data set also includes direct observations of females post-den emergence to ascertain whether or not she was accompanied by cubs as an indicator of reproductive success. The den IDs provided in this data set correspond with those identified in the USGS den catalog (Durner 2010, Durner et al 2020) additional information about the dens in this data set may be found in the catalog.

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.