| MMS ENVIRONMENTAL STUDIES PROGRAM: ONGOING STUDIES | ||||||
| MMS OCS Region: | Alaska | |||||
| Title: | Use of Sea Ice Habitat by Polar Bears in the Southern Beaufort Sea (AK-01-07) | |||||
| Total Cost: | $60,000 | Period of Performance: | FY 2002-2003 | |||
| Conducting Organization: | USGS Biological Resources Division | |||||
| MMS Contact: | Chief, Alaska Environmental Studies Section | |||||
| Description: | ||||||
| Background | ||||||
| Polar bears (Ursus maritimus) occupy ice-covered seas in northern and western Alaska. Polar bears remain with the sea ice throughout the year, and their range generally reflects the seasonal extent of sea ice. Availability of their principle prey, ringed seals (Phoca hispida), is dependent on the form and stage of sea ice. In particular, the near-shore region of the Beaufort Sea is an important hunting area for polar bears soon after the autumn ice has formed. Near-shore ice also serves as a stable substrate for maternal dens during the winter, and as an area in which seals are hunted by adult female bears with their new young during the spring. | ||||||
| Petroleum companies have extended their activities to include these nearshore areas as potential locations for exploration, construction of facilities, and extraction of oil. In addition to existing development, the petroleum industry will likely become increasingly interested in developing nearshore polar bear habitat as new recoverable hydrocarbon deposits are identified. Industrial development in polar bear habitat may result in displacement of bears from foraging and denning habitat because of activities associated with exploration and construction. Bears may die or experience chronic negative health effects as a result of spills of crude oil or other chemicals. In general, polar bears may be exposed to toxic substances and have an increased likelihood of direct interactions with humans. | ||||||
| Polar bears inhabit an environment that constrains direct observation of their behavior. Additional information about habitat use by bears would help managers make decisions regarding how to conduct human activities relative to sea ice conditions in polar bear habitat in the southern Beaufort Sea. With better data on polar bear behavior, the effect of human perturbations could possibly be reduced if human activities were managed to take into account polar bear ice-habitat relationships. Data on polar bear movements and sea ice conditions exist but have not been merged to permit analysis of polar bear habitat preferences relative to ice conditions. | ||||||
| Objectives | ||||||
| The objective of this study is to quantitatively describe the ice habitat types preferred by polar bears in the southern Beaufort Sea. | ||||||
| Methods | ||||||
| Polar bear locations obtained by satellite radio-telemetry will be associated with NOAA weekly ice charts. Ice charts that include the coast of the Beaufort and Chukchi Seas are available and updated on a weekly basis from the National Ice Center (Washington, D.C.). This information will be obtained from the National Ice Center through the Internet. Charts are geo-referenced and ice is identified by form, stage, and the percent of open water. Data are available either as GIF files for producing hard copies or as geographic information system (GIS) software ARC/INFO export files for spatial analysis. Locations have been recorded for instrumented adult female polar bears in Alaska since 1985. ARC/INFO will be used to extract ice habitat attributes and attach those attributes to polar bear locations. Habitat preferences and avoidance will be analyzed using log-linear statistical models. Habitat use will be compared by season and reproductive status of bears. | ||||||
| Importance to MMS | ||||||
| Polar bears are highly susceptible to spilled oil. The species is protected under the Marine Mammal Protection Act and any "take" by disturbance, mortality, or otherwise requires a Federal Permit. Concerns of polar bear welfare raised in environmental impact statements can be addressed by the information gained through this study. Industrial activity in the southern Beaufort Sea is ongoing and will continue into the future, necessitating baseline data of polar bear habitat use. | ||||||
| Current Status: | ||||||
| The BRD has analyzed 1741 locations collected from 51 female polar bears wearing radio collars between autumn 1997 and spring 2001. Some of the preliminary results indicate that the Habitat Selection "Function" by female polar bears is correlated to thick 1st year ice, and proximity to shore. | ||||||
| Final Report Due: | December 2002 | |||||
| Publications: | ||||||
| Affiliated WWW Sites: | ||||||
| Revised date: | March 2002 | |||||
| ESPIS |
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