Northern Fur Seal - Range

Range

The northern fur seal is found in the north Pacific – its southernmost reach is a line that runs roughly from the southern tip of Japan to the southern tip of the Baja California Peninsula, the Sea of Okhotsk and the Bering Sea. There are estimated to be around 1.1 million northern fur seals across the range, of which roughly half breed on the Pribilof Islands in the east Bering Sea. Another 200–250,000 breed on the Commander Islands in the west Bering Sea, some 100,000 breed on the Tyulen'i Islands off the coast of Sakhalin in the southwest Sea of Okhotsk, and another 60–70,000 in the central Kuril Islands in Russia. Smaller rookeries (around 5,000 animals) are found on Bogoslof Island in the Aleutian Chain and San Miguel Island in the Channel Island group off the coast of California. Recent evidence from stable isotope analysis of Holocene fur seal bone collagen (δ13C and δ15N) indicates prior to the maritime fur trade, it was more common for these animals to breed at local rookeries in British Columbia, California and likely along much of the northwest coast of North America.

During the winter months, northern fur seals display a net movement southward, with animals from Russian rookeries regularly entering Japanese and Korean waters in the Sea of Japan and Alaskan animals moving along the central and eastern Pacific as far as Baja California.

The northern fur seal's range overlaps almost exactly with that of Steller sea lions, with which they occasionally cohabit reproductive rookeries, notably in the Kurils, the Commander Islands and Tyulen'i Islands. The only other fur seal found in the Northern Hemisphere is the Guadalupe fur seal which overlaps slightly with the northern fur seal's range in California.