Under the Marine Mammal Protection Act (MMPA) of 1972, NMFS has responsibility for the management and conservation of all marine mammal species in the North Pacific, with the exception of Pacific walrus, Odobenus
rosmarus divergens; sea otter, Enhydra lutris; and polar bear, Ursus maritimus, which are managed by USFWS.
As a result, the American whalers tried to "offset poor catches" by hunting walruses, Odobenus
rosmarus, and gray whales during the "middle season" between late spring and autumn.
These observations contain the date and geographical position of the vessel, often the wind's direction and velocity, the visibility, ice coverage, and usually the fauna encountered (for example, bowhead, gray whale, Eschrichtius robustus; right whale (4), Eubalaena glacialis; humpback whale, Megaptera novaeangliae; walrus, Odobenus
Pacific walrus, Odobenus
rosmarus divergens, occur throughout the Chukchi and Bering Seas, with the southernmost major haulouts occurring in northern Bristol Bay on the islands of Round Island and the Twins, as well as on Cape Pierce.
1999), and walrus, Odobenus
rosmarus (Taylor et al.