Sexual Behavior of Bowhead Whales Observed Off the North Coast of Alaska

Abstract

, aerial surveys were conducted off the north coast of Alaska to delineate migratory patterns of bowhead whales (Balaena mysticetus) in the Chukchi and Beaufort Seas. At 1620 hours on 8 May 1976 approximately 32 km east of Point Barrow (71°24.4N, 156"ll.O'W) we observed and photographed a group of six bowhead whales engaged in sexual behavior in an open water "lead" in the pack ice. Pack ice appeared to be solid east of the region where sightings occurred, suggesting that the animals were detained during migration. A series of 15, 35mm photographs taken with a motor drive attachment provided a clear record of the observation. To facilitate discussion of the sequence of events, the whales are numbered from left to right in a sketch (Fig. la) made from a representative photo (Fig. lb). The aspect of each whale will be described as dorsal, lateral, or ventral, depending on which surface of the whale was toward the observer. Whale 1 was positioned laterally with its dorsal surface toward the outer edge of the photograph. Its head was partially out of the water. Whale 2 was positioned dorsally, and both 1 and 2 were moving slowly in a counterclockwise direction toward the bottom of the photograph. Whale 3 was approximately two meters beneath the surface, with its head directly beneath whale 5 , possibly pushing up 5's head. Later in the sequence of photographs whale 3 moved out from under whale 5 as whale 5 rolled forward and downward.