Occurrence, photo ID and killer whales (Orcinus orca, Linnaueus, 1758) feeding on catch during longline fishing in the Sea of Okhotsk in 2017
PAVEL S. GUSHCHEROV, IGOR A. NABEREZHNYKH, PETR A. TIUPELEEV, ANTON A. NOVOZHILOV
Registration of killer whales was carried out while on bottom longline fishing of black halibut in the Sea of Okhotsk in spring-summer period. At least 100 killer whales specializing on feeding on black halibut have been registered. A ratio of longlines attacked by killer whales (21%) to the total number of black halibut longlines is provided. The pictures taken have allowed pre-identification of 19 killer whales. The data collected allow proposing that the killer whales that feed on longline fishing do not have narrow food specialization, which questions the division of killer whales into two ecotypes, while the observed differences in the diets of different families are related to seasonality of food and to possession of skills in specific hunting methods for individual groups.