Altogether, 21 species of cetaceans have been registered in the coastal waters of the Commander Islands Archipelago (15 toothed and 6 baleen whales species); of those, 11 are included in the Kamchatka Red Data Book. The Commander's beaked whale and the North Pacific giant whales were first described by examples found in the Commander Islands coasts. Feeding areas or migration routes for cachalots, grampuses, beaked whales, Dall’s porpoises, mink whales, sei whales, fin whales, humpback, blue, gray and Japanese whales are located in these coastal waters.
The marine water area of the Commander Islands is used as the feeding area for the humpback whales which are listed in the Russian Federation Red Data Book; their numbers have been steadily growing in the recent years. In addition, such rare species of whales as the North Pacific giant whales, Cuvier beaked whales, Commander beaked whales also occur in the waters of the Commander Islands. Monitoring of the whales' numbers in the Commander Islands’ water area is one of the priority goals for the reserve and the UNDP - Global Environment Facility (GEF) project.