Arctic Field Projects
Project Title: Adaptive long-term fasting in land- and ice-bound polar bears: coping with ice loss in the Arctic? (Award# 0732713)
PI: Harlow, Henry J (hharlow@uwyo.edu)
Phone: (307) 766.3321
Institute/Department: U of Wyoming, Department of Zoology
IPY Project? YES
Funding Agency: US\Federal\NSF\OD\OPP\ARC\ANS
Program Manager: Dr. Henrietta Edmonds (hedmonds@nsf.gov )
Discipline(s): | Biology\Ecophysiology | Biology\Spatial Analyses |
Science Summary:
The largest segment of the world’s polar bear (Ursus maritimus) population follows the retreating sea ice northward and spends much of the summer and early fall on the pack ice offshore. These individuals likely contend with different conditions than those experienced by land-bound bears. Cooler temperatures on the pack ice and potential opportunistic predation of seals (Phoca hispida and Erignathus barbatus) and walruses (Odobenus rosmarus) may result in a higher activity profile and food intake which may lead to lower skeletal muscle atrophy, reduced risk of heart disease by ingestion of omega-3 fatty acids, and maintenance of fat and protein reserves that could be allocated to reproduction. Because the capacity of polar bears to withstand extended periods of fasting is finite, it is possible that the ability of polar bears to remain on the pack ice year round minimizes the negative effects of reduced foraging opportunities associated with declines in annual sea ice and may buffer polar bears from the ill effects of climate change. Nonetheless, reduced primary productivity and thinning of multiyear ice and continued ice loss in the Arctic may force all bears onto land and this physiological buffer may be lost, thus rendering population projections based on current conditions incorrect. The researchers will use a combination of in vivo sampling of movements, body temperature, and muscle strength and fatigue, and lab analyses of stable isotopes, blood chemistry, fatty acid and amino acid profiles, and protein synthesis, to establish whether polar bears that follow the pack ice north of the continental shelf off Alaska experience food deprivation, prolonged adaptive fasting, and skeletal muscle protein and strength retention in comparison with land-bound bears. They will then incorporate these data into models that forecast changes in polar bear population in relation to sea ice conditions. This research is a collaborative endeavor between the National Science Foundation (including use of EPSCoR funds for graduate and undergraduate fellowships through the University of Wyoming program in Ecology), the University of Wyoming, the US Geological Survey and the US Fish and Wildlife Service. This project provides opportunities for students and young researchers (with emphasis on increasing ethnic and cultural diversity). The team will disseminate results through professional presentations and lectures to the public, resource managers, students, and school children. They also will write scientific papers and popular articles. Further, experts will use information gathered for conservation efforts by the USGS and USFWS. In addition, all data and reports will be posted on the Internet.
Logistics Summary:
This grant funds biological and ecological studies of polar bears aimed at understanding what the impact of retreating summer sea ice in the Beaufort Sea region of the Arctic may have on these animals (who use sea ice to hunt). Working in close collaboration with United States Geological Survey (USGS) teams, the NSF researchers will study bears at the beginning of the ice-retreat period in the summer, and shortly before annual ice is re-formed in autumn, along the Beaufort Sea coast during field seasons in 2008 and 2009. The goal of the study is to establish whether polar bears that follow the pack ice north of the continental shelf experience food deprivation, and to estimate their ability for prolonged adaptive fasting and skeletal muscle protein and strength retention in comparison with land-bound bears. In 2008, a team will base from Prudhoe Bay for a two-phased field effort. Using helicopter support to reach their subjects, the team will capture, tag (with GPS radio collars), collect samples from and assess bears after the annual sea ice break-up, in August. They then will return in October to recapture and study some subset of their sample population. In 2009, the Harlow team will visit the region three times: in April/May and October. During the first two trips, the group will lodge in Deadhorse and commute daily via helicopter. The final capture period will be onboard an ice breaker, with a brief stay in Barrow, from which they will use onboard helicopters to capture bears on the fast ice. The bears will be weighed, examined, sampled, tagged and released. During the month-long trip in April/May, the four person Harlow team will have its own helicopter but will work in conjunction with the USGS capture team and helicopter. Some other resources (for example, a helicopter mechanic) will be shared with the USGS team. The October trips will involve intermingling support with the USGS. PolarTREC teacher, Cristina Galvan (0632401CG), will join the field team in October. In 2010, the group will return to Deadhorse for recaptures in April/May in particular to recapture bears that received temperature logger implants in 2008 and 2009 but which have not yet been recaptured. In addition to logger retrievals, these recaptures will greatly increase the sample sizes for blood and breath analyses.
In 2008, the USFWS will provide an R44 helicopter to assist with gear transport and animal spotting in August; the USFWS will also provide a spotting plane. For 2008 and 2009, USGS will assist with all operations but will cover costs related to their own room and board. USGS will provide all helicopter support for the August period. USGS will cover remote fuel costs at Barter Island and Lonely. The US Department of the Interior (DOI) Aviation Management Directorate (AMD) will work directly with the NSF to provide air support in 2008 and 2009, though CPS is involved in developing tasking and coordinating communication. For 2008 and the spring 2009 trip, CPS will provide lab space with power and water, a chest freezer for sample storage, lodging and per diem, communications equipment and vehicle rental and will cover the cost for the Oilfield Unescorted training, if needed. For the August 2009 trip, CPS support will be limited to lodging and per diem and vehicle rental. CPS can cover one charter flight to Kaktovik, if needed. For 2010 work, CPS will provide Prudhoe user days.
| Season | Field Site | Date In | Date Out | #People |
| 2008 | Alaska - Prudhoe Bay | 08 / 02 / 2008 | 10 / 21 / 2008 | 6 |
| 2008 | Arctic Ocean and Seas - Beaufort Sea | 08 / 02 / 2008 | 10 / 21 / 2008 | 6 |
| 2009 | Alaska - Prudhoe Bay | 04 / 14 / 2009 | 11 / 30 / 2009 | 5 |
| 2009 | Arctic Ocean and Seas - Beaufort Sea | 04 / 14 / 2009 | 11 / 30 / 2009 | 5 |
| 2010 | Alaska - Prudhoe Bay | 4 | ||
| 2010 | Arctic Ocean and Seas - Beaufort Sea | 4 |
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