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RESEARCH ARTICLE
Contents Vol 30(6)

Recent surveys of the sea otter (Enhydra lutris) population on Kuril Islands

Igor Popov https://orcid.org/0000-0002-2564-3294 A * and Anton Iurmanov B
+ Author Affiliations
- Author Affiliations

A Department of Applied Ecology, Faculty of Biology, St. Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg 199034, Russia.

B K.A. Timiryazev Institute of Plant Physiology Russian Academy of Sciences, Street Botanicheskaya, 35, Moscow 127276, Russia. Email: yurmanov-anton.ya.ru@yandex.ru

* Correspondence to: i.y.popov@spbu.ru

Handling Editor: Mike Calver

Pacific Conservation Biology 30, PC24026 https://doi.org/10.1071/PC24026
Submitted: 3 April 2024  Accepted: 7 October 2024  Published: 24 October 2024

© 2024 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Context

Sea otters, an endangered species, require regular assessments of their distribution and abundance. These animals inhabit the coastal waters of the North Pacific, traversing from Japan through the Kurils, southern Kamchatka, Commander and Aleutian Islands, and the coasts of North America, to California. Although populations in America and the Commander Islands have been consistently monitored over recent decades, the same cannot be said for the Kuril Islands.

Aim

This study aims to estimate the state of sea otter populations on the Kuril Islands.

Methods

The study area encompassed a section of the Kuril archipelago, including Iturup, Urup, Broughton, Chirpoy, and Simushir Islands, surveyed from 2019 to 2023. Sea otters were counted along sections of the coastline, and published sources on other Kuril Islands were analysed.

Key results

There are several hundred sea otters within surveyed area, whereas in 1960–1980 ~2000 were reported. The total number of sea otters on the archipelago hardly exceeds 3000. The initial or normal number is not known, but the information on hunting indicates that it was much bigger. Up to the end of 19th century, at least ‘one thousand individuals’ had been harvested annually over several decades; this means that the total number was at least several tens of thousands.

Conclusions

Sea otter populations on the Kuril Islands are in decline, with poaching in the recent past identified as significant contributing factor in a part of the archipelago.

Implications

Urgent conservation measures are imperative to address the decline of sea otter populations.

Keywords: decline, kelp, killer whale, Kuril Islands, pelts, poaching, sea otter, trade.

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