Entanglement of northern fur seals (Callorhinus ursinus) in marine debris on Tyuleniy Island (Sea of Okhotsk) in 1998–2013

• Published in: Marine pollution bulletin 2019-06, Vol.143, p.187-192
• Main Authors: Kuzin, Alexey E., Trukhin, Alexey M.
• Format: Article
• Language: English
• Subjects: Age Factors; Animals; Anthropogenic factors; Aquatic mammals; Debris; Entanglement; Environmental Monitoring; Female; Fishing; Fishing nets; Fur Seals; Islands; Male; Marine debris; Marine mammals; Northern fur seal; Pacific Ocean; Pollution; Rookeries; Ropes; Russia; Sea of Okhotsk; Seals; Tyuleniy Island; Waste Products - statistics & numerical data; Water Pollution; Wounds and Injuries - veterinary
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2019.04.051

The systematic annual observations of the northern fur seal rookery on Tyuleniy (= Robben) Island, Sea of Okhotsk, were started in 1958. Since 1975, all seals entangled in marine debris have been registered. Some of the data on this issue, collected on the island in the late 20th century, were published earlier. This report provides data for the period of completion of the commercial sealing (from 1998 to 2013). During this period, a total of 867 fur seals were observed entangled in marine debris, including 212 bulls, 97 half-bulls, 223 bachelors, and 335 females. The estimated mean annual number of entangled fur seals in 1998–2013 is 1113 individuals. Marine debris was found mainly on the neck and, less frequently, on the head and front flippers of the animals. This included pieces of fishing nets, packaging bands, ropes, fishing lines, and other items of anthropogenic origin. •Among all the entangled fur seals, almost a half (44.3%) had fragments of nets.•The ban on driftnet fishing has led to a decrease in entanglement of seals in the nets.•The estimated mean annual number of entangled seals in 1998–2013 is 1113 animals.•Among the entire age-sex group, entangled half-bulls showed the largest proportion.