100 Places To Remember: The Bering Sea, Russia and the United States
Geschreven op 2-5-2010 - Erik van Erne. Geplaatst in Natuur
A Sea that Feeds Walruses, Polar Bears and Two Superpowers. In 1725, the Danish navigator Vitus Bering led an expedition to Eastern Russia on behalf of the Russian czar, Peter the Great, who wanted to know whether Siberia and North America were connected by land. It took him three years to reach what is today known as the Bering Strait. The great sea stretching south of the narrow strait and covering more than two million square kilometres all the way to the Alaska Peninsula and the Aleutian Islands, was also named after the great explorer.
The Bering Sea is unusually prolific. It provides almost half of the seafood caught in the USA, valued at around $1 billion p.a., and the Russian catch is worth $600 million. It is also home to sea lions, walrus, polar bears and endangered whales such as the blue whale, sperm whale, bowhead whale, humpback whale, killer whale and, the rarest of them all, the North Pacific Right Whale. More than 30 species of seabird breed in the region, including the Spectacled Eider and the endangered Short-tailed Albatross.
The cornerstone of the seas rich biodiversity is the diatom, a large phytoplankton that grows on the underside of the ice. The northern part of the Bering Sea is typically covered in ice for seven months of the year. When the ice melts, the diatoms float to the bottom, creating a rich food layer for sea-floor populations, which then support birds and marine mammals. The walrus plays an essential part in the ecosystem as well; by rooting for food with its whiskered muzzle, its stirs up the seabed and circulates vital nutrients.
With the warming of the oceans, there is little doubt that the biodiversity of the Bering Sea will change. There is already less ice than just a few decades ago, and it melts earlier every year, reducing the size and abundance of the diatoms. As the cold waters grow warmer, the fish and crabs move northwards, eating into food supplies that until now have been reserved for ice-dependent species. This means new mouths to feed and less food for the sea lions, walrus and whales. By the end of the 21st century, all the ice in the Bering Sea may be gone.
