In the far west of Arctic Alaska lies Kasegaluk Lagoon, one of the largest, undiminished coastal lagoon systems in the world, spanning approximately 125 miles of the Chukchi Sea coast. This sheltered, shallow lagoon is important habitat for calving and molting beluga whales. Hundreds of spotted seals and walrus haul out along the barrier islands, also a frequent denning destination for polar bears.
Kasegaluk Lagoon also supports the highest abundance of diversity of bird life of all of Arctic Alaska’s coastal lagoons. As many as half of the world's Pacific black brant descend in late August or early September before beginning their journey to wintering grounds in Baja Mexico. Both sexes are identical in plumage – dark with white necklaces – except that the male's white necklace is larger than the female's. Spectacled eiders nest on the mainland, while Pacific loons seek out inland lakes, nest on tiny ponds and fish in the lagoon itself. The loons are awkward on land and require 30-50 meters of open water to take flight!