National Geographic : 1997 Mar
BON VOYAGE With an "Off you go" and a friendly shove, lan coaxes a TDR tagged female toward the sea (left). Graduate students Randi Holsvik and Bjorn Krafft help make sure that the pup soon fol lows. The seals' journey will then become a part of our own. We'll check their locations daily-weather permitting-for the next few weeks, keeping as far as three miles away. If all goes well, we'll recapture these seals just before the pup is weaned, then download their TDR data into our portable computers. From data collected so far, we've learned that mothers attend their pups very closely during the first week of life, mir roring their babies' dives. But pups soon become more inde pendent, spending less synchro nized time with their mothers and venturing out on their own. Satellite data from one of our earlier studies show that one pup took a jaunt to Greenland just a few months after being weaned. Before any captured seals are released, we take blood samples and attach flipper tags for identi fication, which the animals will wear for life. This process leaves the snow bloodstained but the seals unhurt. (Pups have occa sionally been known to doze off while being worked on.) Once we have collected blood samples from enough animals, we'll begin to study their DNA to learn more about their genetic makeup, mating patterns, and population distinctions. We'll also analyze their blood for con taminants. Bearded seals may accumulate concentrations of toxic compounds such as PCBs, found in the clams and some other invertebrates the seals eat. Our work on the ice complete, it's gratifying to watch a bearded seal glide back into the sea (be low). Her neon color mark will soon molt off, but her contribu tion to our knowledge of the spe cies will remain.