The entire population migrates through the lease area from 

 April to June and are found primarily west of the lease area 

 from September to December. 



The northeastern Chukchi Sea is important for both spring 

 and autumn migration, nearshore in the spring, and less so 

 during autumn. Bowheads probably feed in the northeastern 

 Chukchi Sea during autumn, most likely from September to 

 December. If some bowheads do not migrate into the Beaufort 

 Sea during the spring, then it seems likely that some whales oc- 

 cur west and perhaps southwest of Point Barrow from late 

 summer on, especially during years of heavy ice. 



Beaufort Sea 



For an assessment of the occurrence of bowheads in or adja- 

 cent to existing or anticipated OCS lease areas in the Beaufort 

 Sea, we consider the Beaufort Sea east of long. 150°W first, 

 then west to approximately Point Barrow. This was done 

 because 1) of the high probability that the western Beaufort 

 Sea will soon be considered for OCS leasing, and 2) we have 

 more site specific information on bowheads west of long. 

 150°Wthan east. 



East of Longitude 150° W 



The fact that few sightings (5) were made of bowheads with- 

 in or adjacent to the existing OCS lease area (approximately 

 between Colville River and Flaxman Island) between 1974 and 

 1978 makes it extremely difficult to determine what effects oil 

 and gas development may have on the population (Table 4). 

 Since 1974 we have made, or obtained, 53 fall sightings total- 

 ing approximately 323 animals for the entire Beaufort Sea 

 (Fig. 30). Only about 23% (a total of 15 animals) were made 

 east of long. 150°W. The paucity of sightings is directly pro- 

 portional to effort: We were not able to conduct extensive sur- 

 veys east of long. 150 °W because of poor flying weather. 



east fork of the Canning River (east edge of OCS lease area) in 

 the fall of 1973. 



Commercial whalers frequently followed bowheads during 

 the late summer and autumn months from the western Cana- 

 dian Beaufort Sea to the Chukchi Sea, yet few whales were 

 taken near the OCS lease area (Fig. 2). This may have been 

 because 1) few whales were present, 2) whales occurred in 

 areas where the whalers could not go (e.g., in shallow waters), 

 3) the whales moved swiftly through the area and thus were 

 difficult for the whalers to catch, and/or 4) whales occurred 

 farther offshore near or in the pack ice. The net result is that 

 we simply do not know how important the Beaufort Sea OCS 

 lease area is to the bowhead whale. However, if they are pres- 

 ent in any significant numbers, then they probably occur from 

 late August to mid-October. Unfortunately, we have very little 

 data to verify the precise timing and magnitude of their move- 

 ments. Recent sightings of bowheads in and adjacent to this 

 lease site by Ljungblad (1981) confirm that at least some bow- 

 heads frequent the nearshore environs in the eastern and cen- 

 tral Beaufort Sea in autumn. We do know a few bowheads 

 have been sighted or taken by Eskimos in the OCS area in the 

 past 50 yr. 



Eskimo whalers at Kaktovik, Barter Island, hunt bowheads 

 as the whales head west on their autumn migration. They in- 

 form us that the autumn migration is segregated roughly into 

 age classes. Smaller whales pass by early in the autumn and 

 larger whales, including cow-calf pairs, pass by later. Whales 

 are often first seen by late August, and later are seen near the 

 pack ice as the ice moves closer to shore in September and 

 October. The earliest whale taken in memory by Kaktovik 

 Eskimos was 21 August 1972. Bowheads are still going by 

 Barter Island as late as the whalers can get out in their boats 

 and are seen even when the sea is covered with slush ice as 

 late as mid-October. 



West of Longitude 150° W 



Table 4. — Sightings of bowhead whales within and adjacent to the existing Beau- 

 fort Sea Outer Continental Shelf lease area between long. 150° and 145° W within 

 the 12 m depth contour. Data compiled from aerial surveys conducted between 

 1974 and 1978. Positions are approximate. 







No. of 



Latitude 



Longitude 



Information 



Date 



Time 



animals 



(N) 



(W) 



source 



21 Sept. 1974 



1528 



l(t) 1 



70° 13' 



146°39' 



NMFS 



12 Sept. 1975 



1130 



1 



70° 16' 



147°21' 



NMFS 



2 Aug. 1977 



2300 



l(t)' 



70° 35' 



150° 00' 



S. R. Johnson 2 



21 Sept. 1977 



1243 



1 



70° 30' 



149° 00' 



NMFS 



21 Sept. 1977 



1442 



1 



70° 20' 



146° 20' 



NMFS 



'(t) = tentative. 



: LGL, Edmonton. Alberta, Canada, pers. commun. 20 September 1977. 



Results nevertheless indicate that bowheads do visit the OCS 

 lease area, as 38% of our sightings east of long. 150°W were 

 within or adjacent to the barrier islands between long. 145° 

 and 150°W (Fig. 30). Other evidence exists for the occurrence 

 of bowheads in the OCS lease area. In autumn 1921 Sara 

 Kunaknana's (Kaktovik, Barter Island, Alaska) family took a 

 whale on Cross Island; and in 1935 they took another whale in 

 ihe "Prudhoe Bay area." 14 A whale was also taken near the 



Bowheads apparently frequent the inshore waters of the 

 Beaufort Sea between Point Barrow and Smith Bay on an an- 

 nual basis (Figs. 24, 25, 30). Though we have spent more time 

 flying offshore (out to 225 km) than nearshore west of long. 

 150°W, most animals were sighted within only a few kilome- 

 ters of the coast. Most were seen in September (over 90%), but 

 sightings made in August (Fig. 22; A. Brower, Sr. )5 ), and one 

 in November" point out that the time of occurrence here, as 

 well as east of long. 150°W, covers a longer period than we 

 previously thought (Table 2). Again, the timing of migration 

 and occurrence undoubtedly varies somewhat among years. 



We observed bowheads feeding east of Point Barrow to 

 Smith Bay during September 1976. The whales were observed 

 in shallow water, adjacent to the Plover Islands (Fig. 24). 

 The same occurrence and behavior was observed in 1974, 37 

 1975 (Ray in Braham and Krogman footnote 2), and 1978 

 (Braham et al. 1980d) (Fig. 30). On 21 September 1976, R. 



"G. Jarrell, National Marine Fisheries Service, NOAA, pers. commun. 15 

 October 1978. 



J! A. Brower, Sr., Barrow, Alaska, pers. commun. 20 December 1977. 



"J. Burns, Alaska Department of Fish and Game, Fairbanks, Alaska, pers. 

 commun. 20 December 1977. 



"C. Fiscus, Natl. Mar. Mammal Lab., Natl. Mar. Fish. Serv., NOAA, 7600 

 Sand Point Way NE., Bldg. 32, Seattle, WA 98115, pers. commun. 28 Septem- 

 ber 1976. 



25 



