Sea Ice Loss & Polar Bear Food Sources (Steve Amstrup)

Video Shot in: 2022

Steve Amstrup highlights the importance of sea ice for polar bears’ survival and explains that despite increasing primary productivity in some areas of the Arctic Ocean, it doesn’t necessarily benefit polar bears. While the productivity increase might be suitable for other species, polar bears primarily rely on catching seals from the surface of the ice. Seals, in turn, depend on the productivity that starts on the underside of the sea ice. If the sea ice diminishes or disappears, polar bears lose their essential hunting platform, and seals lose the nourishment they need. Steve refutes the idea that polar bears could simply adapt to land-based hunting, citing evidence from the past when polar bears disappeared from regions where the sea ice retreated. He emphasizes that the Arctic’s unique ecosystem supports large polar bear populations, while adjacent terrestrial environments, home to grizzly bears, can only sustain small numbers of smaller bears. Steve concludes that maintaining healthy populations of the world’s largest bears requires preserving the sea ice and the nutritious food source it provides for them.