Time Flies When You’re Tagging Seals

Baylis, Nordstrom & Gibbens choosing fur seals for tagging.

When we last left our intrepid Consortium researchers, Chad Nordstrom and Brian Battaile were packing for a summer field season off the coast of Alaska, anticipating the months they’d spend in relative isolation, with more fur seals than humans for company. The two biologists are an integral part of the Patch Dynamics Study funded by the North Pacific Research Board to determine the effects of spatial variations in prey on predator-prey relations. Nordstrom and Battaile set out in early July to spend the summer and early fall tagging northern fur seals and tracking their movements and patterns. So how did they make out?

Good Company Offsets Bad Weather on the Pribilof Island
Arguably, Nordstrom had the cushier of the two placements. Stationed on St. Paul Island in the Pribilofs, his living conditions entailed a house in the Aleut community of St. Paul, shared with two friendly fur seal researchers from Australia — Alistair Baylis and John Gibbens — and a team of bird scientists. The good company almost made up for the dismal weather — fog, wind, and rain — that prevailed most of the summer, leaving the team pale and hungry for Vitamin D.

Excellent team dynamics translated into successful research. The researchers had hoped to outfit 30 female fur seals with telemetry tags that would record their foraging journeys, but managed to tag 46. The greatest limiting factors, they found, were the small number of tags they had to work with and the long journeys the fur seals took. Some seals spent up to 12 days at sea before returning with the tags.

Late in the season, Nordstrom was looking forward to returning home (especially to the red licorice he had been craving all summer), but was also reluctant to leave the fascinating seal rookery and the curious pups that had just begun to explore it.

Team MacGyver on Bogoslof Island
Meanwhile, on a 0.7 square-kilometer uninhabited volcanic island some 250 miles away, Brian Battaile and his research assistant Rob Marshall were also celebrating a successful research season. They deployed 11 more tags than their projected 36, with only a few technical blips — but nothing a bit of MacGyver-ing with wire and a hacksaw couldn’t fix.

This past season, Bogoslof Island played host to six researchers (the fur seal team and a four-person bird crew). In addition to their tents, the researchers had a tiny plywood cabin to house their gear and a portable “weatherport” for cooking and socializing.

Conditions were spartan, but the researchers remained stoic, chalking July’s downpours up to excellent dish-washing weather. Wanting for nothing but a second pair of gloves and some tar to seal the cabin roof, Battaile did not miss Vancouver’s bustle, or even his Internet connection.

Home Again, Home Again
Now home safe and sound, the researchers are analyzing the data they collected. Nordstrom is focusing on the oceanographic aspects of the study, mapping water temperatures around the islands and at different depths, while Battaile concentrates on foraging ecology — how and where fur seals feed. According to Battaile, this could prove challenging, as very little information on how to statistically analyze such data exists. He looks forward to creating a novel method of analysis, which if he remains true to form might well involve duct tape and chewing gum!

Individual foragaing trips by lactating northern fur seals tagged on St. Paul Island and Bogoslof Island in 2009.

October 29, 2009