Early spring distribution of bowhead whales in the Bering Sea

Helicopter surveys were conducted of the pack ice in the northwestern Bering Sea during early spring 1979 to determine bowhead whale (Balaena mysticetus) distribution. One hundred and nine bowheads were observed in the approximately 15,000 km2surveyed. Whale use of the pack ice was disproportionately highest in the 3-4 okta ice concentration category and lowest in the 7-8 okta category; the 1-2 and 5-6 okta categories were used in proportion to their availability. The association of whales with these ice concentration categories appeared to suggest the possible location of a spring migration corridor. No calves were observed during the study.