Table 3. — Area use and limetable for Ihe majority of the bow head whale population in or adjacent to 

 proposed Outer Continental Shelf (OCS) lease areas of Ihe Bering. Chukchi, and Beaufort Seas. 

 Some exceptions exist, of course. 



OCS 



Temporal 



use 



Spatial use 





areas 



Present 





Absent 



Present 



Absent 



St. George Basin- 



Essentially absent, 



a 



few may 



west-central 1 



Remaining? 



outer Bristol Bay 



occur irregularis 

 in the western si 



■ in 

 de 



the spring 



St. George Basin 





Navarin Basin 



Feb. -Apr. 





May-Jan. 



Unknow'n 



Unknown 



Norton Sound- 



Mar. -June, 





Feb., 



Western half 



Norton 



No. Bering Sea 



Oct. -Jan. 





July-Sept. 





Sound 1 



Hope Basin 



Apr. -June, 





Jan. -Mar., 



West of long. 



Kotzebue 



(Chukchi Sea) 



Sept. -Dec. 





July-Aug. 



164°W 



Sound" 



Beaufort Sea 



Apr. -June, 





Dec. -Mar. 



Nearshore and 







Aug. -Nov. 





July? 



offshore 





If and when present. 

 : During most years. 

 'East of long. 164°\V. 



The migration rouie along ihe west side of St. Lawrence 

 Island ihen lakes ihe whales through ihe western poriion of the 

 NBS OCS lease area west of an imaginary line from Savoonga 

 to Cape Prince of Wales. Whales in spring are on occasion 

 seen in open water easi of Gambell 10 west of Savoonga (closer 

 to Gambell). Open water increases from east 10 west towards 

 the Chukotka Peninsula. We conclude that most bowheads 

 migrate through the western half of the NBS OCS lease area in 

 the spring, during average ice years. Eskimos also report that 

 some bowheads migrate around the east end of St. Lawrence 

 Island in the spring. We have only two 'sightings at the east end 

 of the island since 1976. We do not believe that the east end of 

 the island is an important migration corridor. A more detailed 

 description of the spring migration is covered in Braham el al. 

 (1980b). 



No records were found nor sightings made by us prior to 

 1980 of bowheads in the eastern portion (east of long. 166°W) 

 of the NBS OCS lease area (i.e., Norton Sound). More than 10 

 bowheads were observed in Norton Sound in May 1980; at 

 least 5 were seen near Norton Bay. These animals occurred 

 here as a result of an ice blockage in the Bering Strait which 

 halted their spring migration. Although a complete account of 

 the number and location of bowheads in Norton Sound during 

 the spring of 1980 was not available for this revised report. 

 Johnson et al. (1981) summarized the causes for the delayed 

 migration. The important point here is that, given the proper 

 conditions, bowheads can be found throughout ihe NBS OCS 

 lease area but in low numbers in Norton Sound. 



The autumn migration pattern in ihe NBS is less clear than 

 for the spring, but apparently bowheads can be seen across the 

 north side of St. Lawrence Island, suggesting that the migra- 

 tion path in autumn may be more diffuse than in spring. Sev- 

 eral Eskimos at St. Lawrence Island have told us that bow- 

 heads do not migrate around the east end of the island in the 

 autumn but rather move by the west end. 



The waters adjacent to St. Lawrence Island are important to 

 ihe survival of this population. The Bering Strait is also impor- 

 tant because the entire bowhead population passes through it 

 twice annually. The autumn period in the Bering Strait may be 

 more important than the spring because if bowheads were 

 limited or restricted from entering the Chukchi and Beaufort 

 Seas in the spring, they would still be able to feed throughout 



the summer in the ice-free waters of the northern Bering Sea. 

 Townsend (1935) clearly showed that bowheads once occurred 

 in the NBS in the summer, a period thought to be a traditional 

 feeding time for the species. However, if restricted from mov- 

 ing into the Bering Sea in autumn, some, if not many bow- 

 heads might be trapped by winter freezeup. 



In conclusion the following points can be made from our in- 

 vestigations: 1) In spring, bowheads are more likely to migrate 

 through the western portion of the NBS OCS lease area than 

 to the east. 2) The autumn-winter migration in the NBS prob- 

 ably occurs throughout most of the western NBS, but no in- 

 formation exists to help us predict how far east into outer Nor- 

 ton Sound they occur. 3) Inner Norton Sound (east of long. 

 166°W) is seldom used by bowhead whales, and does not in- 

 clude important habitat. 4) Waters adjacent to St. Lawrence 

 Island and the Bering Strait may be critical habitat areas for 

 the stability and survival of this population. 



Hope Basin and Northeastern Chukchi Sea 



Very little is known of the specific movements of bowheads 

 in the Hope Basin (south of lat. 69 °N, east of long. 169 °W) 

 and northeastern Chukchi Sea (north of lat. 69 °N, east of 

 long. 160°W). From April to June, bowheads migrate north in 

 leads through the pack ice flaw zone from the Bering Strait to 

 an area stretching from Kivalina out to, on some occasions, 90 

 km offshore Point Hope. For additional specific details, see 

 Braham et al. (1980b) and Johnson et al. (1981). 



The autumn migration through the northern Chukchi Sea 

 and Hope Basin to the Bering Sea appears to be farther off- 

 shore than during the spring. Bowheads are not known to fre- 

 quent Kotzebue Sound (east of long. I64°W) with any regu- 

 larity. Townsend's (1935) plots of harvested whales (Fig. 2) in- 

 dicated that the western portion of the Hope Basin was more 

 heavily exploited, presumably a reflection of bowhead distri- 

 bution. We believe that bowheads are generally found west of 

 this lease area during autumn (September-November) (Braham 

 et al. 1980c; Dahlheim et al. 1980; Johnson et al. 1981). 



In conclusion, bowheads frequent the Hope Basin and 

 northeastern Chukchi Sea during the spring and autumn 

 migration but do not appear to spend a significant portion o( 

 time there for purposes of reproduction, growth, or feeding. 



24 



