Seals are pinnipeds, a group of animals with three separate families—phocidae, otaridae, and odobenidae—that are the only mammals that feed in the water and breed on land. New research shows Weddell seals avoid making extreme dives for prey during midday, allowing the seals to keep diving over and over without having to pause for long. This allows them to spend almost all of their time underwater, foraging under high-light conditions, which is best for visual hunters.

Understanding the Context

(Michelle Shero, ©Woods Hole Oceanographic Institution) WHOI biologist Rebecca Gast examines whether the recovered and thriving population of gray seals in Cape Cod waters has affected water quality off the beaches they frequent. The night approaches quickly. A harbor seal plunges into the water, diving deep as the sunlight recedes. Through the dark, turbid waters, she searches for fish.

Key Insights

Suddenly, the whiskers on her right cheek begin vibrating. And she’s off. Heather Beem is closely examining seal whiskers for insights to design new… A female grey seal nursing her pup on the beaches of Sable Island, Nova Scotia. Gray seals give birth once a year and females will quickly lose ~30% of their body mass while the pup triples in size during a short nursing period of only 15-20 days. Studying how seals adapt to extreme environments could lead to benefits ...

Final Thoughts

This past winter, on a cold, sandy island about 200 miles off the coast of Nova Scotia, a pair of shaggy wild horses supervised the efforts of a small group of seal researchers. “They just stood there and watched us work for a little while,” said Michelle Shero, a marine biologist at WHOI. “They seemed very curious about what we were doing.” As the horses looked on, Shero and her team ...