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The Bering Sea makes up one of the most diverse and rich subpolar and polar marine ecosystems in the world. Where can a bear walk on water? In the Bering Sea ecoregion, where the sea freezes into an ice pack the size of California. This place of water, islands, and ice is remarkably diverse. Polar bears lumber across the ice pack looking for their next meal. The world’s largest mammal, the blue whale, migrates through on its way to and from summering grounds. Seals, sea lions, and walruses heave themselves up on the ice to rest. Salmon, including sockeye, chinook, chum and coho salmon, swim in the ocean before migrating up the rivers to spawn. Millions of seabirds nest in the region’s islands, raising chicks in some of the world’s largest seabird colonies. And so many fish, crustaceans and mollusks inhabit this ecoregion that it’s one of the most productive fishing spots on the planet.
Some sheltered lagoons in the Bering-Beaufort-Chukchi Seas ecoregion are shallow and warm enough to support forests of giant kelp (which can stretch hundreds of feet from the ocean bottom to the surface) and meadows of eelgrass, along with the hundreds of invertebrates and fish that depend on these plants. Other areas are deep, cold, and covered in ice most of the year. In the late spring and summer months, the pack ice breaks up and coastal areas teem with life. Red and blue king crabs, pink shrimp and weathervane scallops live here, along with millions of squid that dart around the ocean using jet propulsion. Nearly two million murres and auklets -- two common seabird species--crowd the region’s cliff faces, where they rest and make their nests. Bald eagles and Stellar’s sea eagles nest in trees and hunt salmon -- the Bering-Beaufort-Chukchi Sea is home to one of the largest runs of salmon in the world. Sockeye, chinook, steelhead, and chum salmon migrate up rivers to spawn each summer and fall, while other fish, such as the yellowfin sole, live in the sea all year round. The Steller sea lion’s favorite fish to eat is the pollock. An incredible diversity of whales swim here, including bowhead whales, Sei whales, Dall’s porpoise, and sperm whales. Seals, sea lions, and Pacific walruses breed and rest on rocky shores but hunt in the sea when they get hungry.
Not surprisingly, the tremendous richness of this ecoregion draws fishermen from all over the world. But in recent years, coastal residents, fishermen, and biologists have documented declines not only in fish, but in Steller sea lions, northern fur seals, and birds such as red-legged kittiwakes and spectacled eiders. Some people think that overfishing by commercial fisheries is making it harder for mammals and birds that depend on fish to survive. Other major threats to the ecoregion are mining along the coasts and pollution from shipping. And many scientists are concerned about the impacts of global climate change on the ice pack. They believe that shrinking ice cover may threaten seals, polar bears, and walruses.
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