Research Objectives:
The primary goal of this program is to quantify the dynamics of lipid uptake and utilization in a naturally foraging mammalian carnivore by examining freely diving Weddell seals in Antarctica. The species and the antarctic environment offers a unique opportunity to follow the biochemistry and physiology of nutrient utilization in a large carnivore that may not be possible in any other system. As such, this project will provide rare and perhaps unparalleled data on the foraging biochemistry of freely living carnivore.
Project team members will establish a sea-ice camp a few miles from McMurdo Station on the fast-ice in an area where there are no other holes or cracks for the seals to use. Seals are then selected at a site along the coastline and brought to the camp. The seal is then allowed to dive through a hole in the sea ice under a hut at the camp. The seal must always come back to the hut to breathe and rest between diving bouts since there is no nearby access to the surface.
Dr. Castellini has used this method of study Weddell seals since 1977. The seals naturally hunt for fish and squid under these conditions and blood samples can be taken whenever the seal is at the surface. Researchers expect to study eight adults (non-lactating females) in the 2004 season. Samples may also be collected in the field from pups to test for lipid levels in their blood after they have been nursing.
