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Climate Drives Change in an Arctic Food Web


Climate-driven changes in sea ice and currents could lead to smaller, less nutritious zooplankton, a new NOAA Fisheries study suggests. These organisms are prey for whales that migrate to the Chukchi Sea to feed. These shifts in zooplankton communities could cascade through the food web to affect other marine life, from forage fish to fish-eating seabirds to bottom-feeding walrus.

An Arctic Hotspot

Zooplankton include small, shrimp-like animals like copepods and krill. Copepods and krill eat algae, and everything from forage fish to whales eats zooplankton.

But not all zooplankton are equal in nutrition. In the Chukchi Sea, Calanus glacialis, a large, energy-rich copepod, is an important food for many animals, including bowhead whales. Twice a year the whales migrate through Chukchi Sea on their way to and from their feeding grounds in the Canadian Beaufort Sea. Some whal