Gray whale research off northeastern Sakahin Island and eastern Kamchatka, Russia: 2020 filed report
Alexander M. Burdin, Olga Sychenko and Matvey Mamaev
In 2020, research onwestern gray whales off northeastern Sakhalin Island and off the southeastern coast of Kamchatka (Kronotsky Bay) wasconducted by the RussianGray Whale Project. In Sakhalin work was conducted from 27 July 27 to 8 September 8during which time 17 boat surveyswere completed. A total of 122 whale groups were encountered (with repeated sightings)and 32 unique whales were identified. Eightmother-calf pairsand four new whales at the age 1+, previously not seen in the study area,were observed in the Piltun feeding area. Thus, our catalog of whales summering offSakhalinbetween 1994-2020 includes 314 individuals. The distribution of whales was similar to2019, but in the period of our work all whales were concentrated only in the area offthe mouth of Piltun Lagoon. In addition, the total numberof gray whales usingthe study area was lower than in 2019 (32 and 49 respectively). In Kronotsky Gulf of the Kamchatka Peninsula (Olga Bay), studies of gray whales were conductedon 12 Julyand 13 August. We encountered 21 and 18 whales (including 2 calves) respectively, of which 8 adult whales (including 2 females) were from the Sakhalin catalog and were previously observed in the Piltun feeding area. Female No. 149 (calf No. 310) was photographedin Olga Bay on 12 Julyand on 4 August resighted off the Piltun Lagoon area (~ 800 nautical miles in 23 days). Whale No. 260 observed in Olga Bay on 12 July was sighted offPiltun on 24 August. The remaining animals (both unknown and those form the Sakhalin Catalog) were not observed in 2020 in the Piltun area. The whale No. 135 from the Sakhalin catalog was met in Olga Bay twice in 12 July and 13 August. The same whale was observed on 9 September 9 in the AvachaGulf (eastern Kamchatka). This data once again confirms the importance of NE Sakhalin as the main feeding area for gray whale females with dependentcalves and yearlings after weaning, as well as the stable connection between feeding (Sakhalin) and transit (Eastern Kamchatka) areas. The absence of some whales from the Sakhalin catalog which were found off the Kamchatka coast in the Piltun feeding area for several years indicates the possibility of the existence of unknown feeding areas (except for offshorefeeding area opposite the Chaivo Lagoon)or simply that they were off Sakhalin but missed by our sampling efforts. Thus, the results of the 2020 research indicate anoverall decrease in the number of gray whales offthe Piltun feeding area and some changes in the distribution of animals off the NE coast of Sakhalin Island.