Special Field Report From Parker Levinson:
We just got back from our first trip out to White Island, an isolated seal colony about 20 miles south of McMurdo station. It’s a really interesting story.
New field video report from Parker Levinson on the isolated White Island colony of Weddell seals.
Usually, Weddell seals reproduce on sea ice or frozen ocean. They’re able to swim miles under the sea ice to form these large pupping colonies away from predators. Then, when the ice breaks out, the seals go elsewhere. We’re not quite sure where they go in the winter months; some probably stay in Erebus Bay, others travel north up the coast in search of food. But what the Erebus Bay seals have in common with the 200,000 other Weddell seals around the Antarctic continent is that they utilize sea ice to breed and to haul out on (Larue 2021).
A Weddell mom with her new pup at the isolated White Island pupping colony. Photo by Parker Levinson.
The White Island seals do not. The White Island seals live on an ice shelf, which is basically a frozen glacier. The thought is that decades ago, most likely in the late 1940s, the ice shelf broke out, allowing seals from Erebus Bay to swim to White Island. As the ice shelf grew back, the seals got trapped behind it, resulting in an isolated population.
Weddell mom with new pup in the distance at White Island. Photo by Parker Levinson.
Geneticists believe the population was founded by two males and three females and is now in its 3rd or 4th generation (Gelatt 2009). To continue surviving and reproducing, seals must find food beneath the ice shelf, swimming through thick ice and extreme darkness. We really don’t know too much about how the life history of seals at White Island differs from those at Erebus bay, although we do know they reproduce a little less frequently.
Heading back to the helicopter at White Island, Antarctica. Photo by Parker Levinsoon.
We go to White Island 1 or 2 times every year to tag the pups, see who is still alive and hauled out on the ice, and collect genetic samples for our collaborators. We take a helicopter out there, conduct an aerial survey of the seals, and then land on the ice shelf to begin our tagging efforts.
Video from a previous pupping season of Jesse DeVoe and Jessica Farrer flying out to
White Island to record the isolated Weddell seal pupping colony there.
We saw 5 adults out there this time and tagged 2 live pups, which is a pretty average year. While we don’t get that many seals out there, visiting White Island always reminds me of how resilient these animals are.
- Parker Levinson, 2023 Field Team Leader and MSU Masters Student
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