ductive activities (Sergeant and Hoek 1974). Later on, due to 

 the gradual dispersal of food (primary fish), Klumov (1939) 

 reported the whales divide into smaller groups and eventually 

 move toward the wintering grounds. 



From a sample size of 2,002 white whales observed during 

 surveys since 1976, we calculated that mean group size was 

 4.8 (SD 0.43, n = 419). The preponderance of sightings oc- 

 curred in April and May. The mean group size estimated is 

 believed to be biased downwards because of a tendency to 

 split larger "groups" when counting from an airplane. 

 Group size estimates made from our ice camps at Point Bar- 

 row varied from 4.8 to 12.4 (no variance estimate) depending 

 on lead width (extent of water). As open water increased, 

 group size decreased. 



Kleinenberg et al. (1964) further detailed the composition 

 of groups with size variation (i.e., 10's or 100's of individ- 

 uals). In groups of 10, the animals were normally traveling 

 by two's and three's, some 10-30 m apart. Within these 

 groups of 10 they found that 1) adults always kept apart; 2) 

 adults often formed the majority of the herd; and 3) the few 

 young that were present remained in the middle of the larger 

 group structure. In groups of 100's, large adult males, form- 

 ing 51.2% of the herd, were followed by females with calves 

 (Dorofeev and Klumov 1936; Arsenyev 1939). Kleinenberg et 

 al. (1964) reported that females were often accompanied by 

 one to three "young" (presumably gray-colored subadults). 



White whales are dark brown to gray in color up to about 



6 yr old. Sexual maturity occurs at approximately 5 yr for fe- 

 males and 8 yr for males (Sergeant 1973). Color change can 

 thus be used to estimate the minimum size of the subadult 

 population. In 1977, we scored 1,699 white whales (including 



7 newborn calves) as to color phase during their annual 

 spring migration past Point Hope, Alaska. It was possible to 

 make a classified count of 507 animals: 316 (62.3%) were 

 white; 166 (32.7%) were gray; and 25 (4.9%) were transi- 

 tional between gray and white. This resulted in an approxi- 

 mate adult to subadult ratio of 2:1. From aerial surveys in 

 1976 and 1977, a ratio of 14:1 (white:gray phase) was esti- 

 mated. We believe the aerial results to be an overestimate 

 because of the short amount of time to count and confirm 

 the color of an animal from the air (for these data years 

 only), and the ice counts to be an underestimate because of 

 the light reflection off gray ice or dark water onto a light 

 object making the object appear darker than actual. Also, we 

 assume that both methods were an unbiased estimate of the 

 population(s). 



RECOMMENDATIONS 



Designation of these areas as of primary importance to the 

 species is partly based on the fact that we have better infor- 

 mation for these areas than for others. Unfortunately, we 

 have less good information for areas which might prove to be 

 of particular importance, e.g., the eastern Beaufort Sea (in- 

 cluding the present OCS lease site), Hope Basin, and the 

 Navarin Basin. However, the eastern Beaufort Sea and the 

 Hope Basin appear to be transition zones for the whales dur- 

 ing their annual migration rather than vital places where they 

 would be most vulnerable. Additional research, particularly 

 in the Beaufort Sea, is needed to verify this point. 



Without precedents regarding effects on whales of oil- 

 related development activities, it is difficult to assess jeopardy 

 to this population, as required by Section 7 of the U.S. En- 

 dangered Species Act of 1972. However, we can predict the 

 times and locations where the population, or at least indi- 

 viduals, would be vulnerable to an oil spill or other possible 

 disturbing activities. The times are outlined by OCS lease 

 area in Table 3. Specifically the above described areas are of 

 greatest significance because we believe bowheads engage in 

 two critical life history phases there — reproduction and feed- 

 ing. They also migrate directly through these areas twice 

 annually. 



Our conclusions are based on 2 yr of OCSEAP research, 

 and two additional years of NMFS studies where, in both 

 cases, we were limited by weather, time, and budget to com- 

 pletely cover all areas visited by bowheads. It is, of course, 

 difficult to draw conclusions on the importance of areas and 

 times within their range where few data exist. 



We are less certain about the times and areas where white 

 whales might be vulnerable. Certainly inner Kotzebue Sound 

 appears to be an important summering area for reproduction 

 and feeding. The northwest coastal waters from Point Lay to 

 Point Barrow appear also to be an important area for white 

 whales, although this may vary among years. But again, be- 

 cause we do not know how many stocks of white whales we 

 are dealing with, site specific vulnerability is particularly dif- 

 ficult to assess. 



White whales appear to occur farther offshore in the U.S. 

 Arctic Ocean than bowheads; perhaps they are less vulnerable 

 to nearshore development. Some do, however, occur very 

 near shore in the eastern Bering and Chukchi Seas during the 

 spring and summer. Because some Eskimo subsistence de- 

 pends upon both species, we urge that site specific studies 

 related to interaction between whale, subsistence activities 

 (hunting requirements), and oil development activities be 

 undertaken or continued. 48 We further urge that ecological 

 studies be conducted, placing greater value on both species 

 habitat requirements and environmental (physical and bio- 

 logical) interaction than previously suggested or conducted. 



Actions Based on Existing Knowledge 



Based on our present state of knowledge of the distribu- 

 tion and biology of the bowhead whale in the Bering, Chuk- 

 chi, and Beaufort Seas, we recommend that serious consider- 

 ation be given to removing or drastically limiting oil and gas 

 development in four important (perhaps critical) habitat 

 areas: 1) The northern Bering Sea around St. Lawrence Is- 

 land. 2) The Bering Strait. 3) Northwest coast of Alaska, 

 Cape Lisburne to Point Barrow. 4) The western U.S. Beau- 

 fort Sea from long. 150°W to Point Barrow. 



"■"Since this paper was written two important studies were conducted on be- 

 havior and distribution of bowheads which we recommend to the reader. 1) 

 Wursig, B., C. Clark. E. Dorsey, M. Fraker, and R. Payne. 1981. Normal be- 

 havior of bowheads. In W. J. Richardson (editor). Behavior, disturbance 

 responses and feeding of bowhead whales in the Beaufort Sea, 1980, p. 21-90. 

 Chapter in unpublished report from LGL Ecol. Res. Assoc, Inc., Bryan, Tex., 

 for U.S. Bureau of Land Management, Wash., D.C. 2) Fraker, M., C. Greene, 

 and B. Wursig. 1981. Disturbance responses of bowheads and characteristics of 

 waterborne noise. /bW.J. Richardson (editor), Behavior, disturbance responses 

 and feeding of bowhead whales in the Beaufort Sea, 1980, p. 91-195. Chapter in 

 unpublished report from LGL Ecol. Res. Assoc, Inc., Bryan, Tex., for U.S. 

 Bureau of Land Management, Wash., D.C. 



30 



