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Filters: Types: OGC WFS Layer (X) > partyWithName: Glen Liston, PhD (X) > partyWithName: National Fish and Wildlife Foundation (X)

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The purpose of this project is to provide better information to industry and regulatory agencies regarding the likely locations of polar bear dens. This project integrates snow physics, high-resolution digital elevation data, and bear biology to produce more refined and accurate maps predicting suitable polar bear den habitat than are currently available. The work consists of data gathering, consultation between snow and bear scientists, modeling, and sensitivity studies to understand the various factors influencing den location and evolution along the Beaufort Coast.The proposed work is intended to refine current methods of identifying polar bear denning sites by incorporating higher-resolution topographic data...
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Historically, available polar bear den habitat models have been based primarily on the presence of topographic features capable of capturing drifting snow. In any given season, however, the availability and precise location of snowdrifts of sufficient size to accommodate a bear den depends on the antecedent snowfall and wind conditions, and these vary from one year to the next. Thus, suitable topography is a necessary pre-condition, but is not sufficient to accurately predict potential den sites in a given year. To satisfy the requirements of agency and industry managers what is needed is a user-friendly decision-support tool that takes into account the current fall and early-winter meteorological conditions, and...
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Throughout the Arctic most pregnant polar bears (Ursus maritimus) construct maternity dens in seasonal snowdrifts that form in wind-shadowed areas. We developed and verified a spatial snowdrift polar bearden habitat model (SnowDens-3D) that predicts snowdrift locations and depths along Alaska’s Beaufort Sea coast. SnowDens-3D integrated snow physics, weather data, and a high-resolution digital elevation model (DEM) to produce predictions of the timing, distribution, and growth of snowdrifts suitable for polar bear dens. SnowDens-3D assimilated 18 winters (1995 through 2012) of observed daily meteorological data and a 2.5 m grid-increment DEM covering 337.5 km2 of the Beaufort Sea coast, and described the snowdrift...
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Historically, available den habitat models have been based primarily on the presence of topographic features capable of capturing drifting snow. In any given season, however, the availability and precise location of snowdrifts of sufficient size to accommodate a bear den depends on the antecedent snowfall and wind conditions, and these vary from one year to the next. Thus, suitable topography is a necessary pre-condition, but is not sufficient to accurately predict potential den sites in a given year.To satisfy the requirements of agency and industry managers what is needed is a user-friendly decision-support tool that takes into account the current fall and early-winter meteorological conditions, and provides den...
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Polar bears along Alaska’s Beaufort Sea frequently give birth to young in land-based snow dens.These dens are established in November, typically in deep snowdrifts that have developed in thelee of cut-banks found along streams, rivers, and the coast. Durner et al. (2001, 2006) indicatedthat, for 24 known land den sites, the local slopes ranged from 15 to 50° and were 1.3 to 34 mhigh. The dens faced all directions but east. They published a distribution map based on habitatcharacteristics, presumably reflecting snow drifting, largely bracketing the generally northwardflowing drainages of the region. No attempt was made in the cited studies to model snow driftingexplicitly, though it was recognized that this was an...


    map background search result map search result map Mapping Suitable Snow Habitat for Polar Bear Denning Along the Beaufort Coast of Alaska Operational Polar Bear Den Mapping SnowDens-3D User Documentation Modeling snowdrift habitat for polar bear dens Mapping Suitable Snow Habitat for Polar Bear Denning Final Report Mapping Suitable Snow Habitat for Polar Bear Denning Along the Beaufort Coast of Alaska Mapping Suitable Snow Habitat for Polar Bear Denning Final Report Operational Polar Bear Den Mapping Modeling snowdrift habitat for polar bear dens SnowDens-3D User Documentation