Chiswell Islands, Alaska Maritime National Wildlife Refuge

Chiswell Islands, Alaska Maritime National Wildlife Refuge

by | Sep 26, 2021

The Chiswell Islands are a group of rocky and uninhabited islands situated at the entrance to Aialik Bay on the south coast of Kenai Fjords National Park, about 67 miles (108 km) east of Homer and 35 miles (56 km) south of Seward, Alaska. The named islands include Granite, Twin, Dora, Harbor, Natoa, Beehive, Matushka, Chiswell, Lone Rock, Seal Rocks, Chat, and Cheval Islands. These islands appear to rise vertically out of the sea and there are virtually no horizontal beaches. The area is very active seismically and evidence of this can be seen in the sheer rock walls and the rough-hewn topography that has been repeatedly carved by glaciers and eroded by waves from the Gulf of Alaska. According to Captain George Vancouver, these islands were named Chiswell Isles in 1786 by Captain Nathaniel Portlock, possibly for Richard Muilman Trench Chiswell. The Russians called them Ayaliki Islands which may have been an Aleut name. The Chiswell Islands are managed by the Alaska Maritime National Wildlife Refuge as part of a sanctuary for seabirds and marine mammals.

The Alaska Maritime National Wildlife Refuge comprises 2,400 islands, headlands, rocks, islets, spires, and reefs in Alaska, with a total area of 4.9 million acres (20,000 sq km), of which 2.64 million acres (10,700 sq km) is wilderness. The refuge stretches from Cape Lisburne in the Chukchi Sea to the tip of the Aleutian Islands in the west and Forrester Island in the Alexander Archipelago of Southeast Alaska. The refuge is known for its abundance of seabirds. About 75 percent of Alaskan native marine birds, 15 to 30 million among 55 species, use the refuge. The Chiswell Islands are inhabited by hundreds of thousands of marine birds. Birds that nest on these islands include horned puffins, tufted puffins, black-legged kittiwakes which nest on the exposed rock face of cliffs, and Cassin’s auklet and the whiskered auklet. Marine mammal haul-outs and rookeries are mostly located on remote and rocky coasts and islands with easy access to the open sea. Several of the Chiswell Islands are used as haulouts by Steller sea lions and Chiswell Island in particular is the only known sea lion rookery in the area.

The Steller sea lion is called ‘seevitchie’ by the Unangan Aleuts and ‘sivuch’ by the Russians, each translating to ‘seawolf’. In 1741, the naturalist George Wilhelm Steller accompanied the expedition of Vitus Bering that discovered Alaska for the Russians. Steller thought the creature resembled a lion because the males have a large neck and shoulders that appear similar to the mane of a male lion. Steller sea lions are the largest members of the eared seal family. In Alaska, these include fur seals, California sea lions, and Steller sea lions. Female sea lions average 7 feet (2.1 m) in length and weigh about 600 pounds (272 kg). Male sea lions average 9 feet (2.7 m) and weigh an average of 1,500 pounds (680 kg) with very large males reaching 2,400 pounds (1089 kg). Steller sea lions are opportunistic marine carnivores. Their most important prey species include pollock, Atka mackerel, Pacific herring, capelin, Pacific sand lance, Pacific cod, and salmon. Orcas and salmon sharks are the top predators of Steller sea lions. The Steller sea lion population in the western Gulf of Alaska declined by 75 percent between 1976 and 1990. The reasons for the decline are not completely understood, however, in the mid to late 20th century, fishermen were paid a $2–6 bounty for sea lions by the U.S. government. In the 1970s, it was not unusual for fishing boats to arrive in Dutch Harbor with dozens of sea lion noses strung together. The original purpose of the bounty was to decrease predation on commercial fish species. The numbers killed probably rose from a level of 1,500 animals per year in the late 1950s to a peak of around 4,000 animals in the early 1980s. Mortality decreased through the late 1980s as the sea lion population declined and public attitudes towards sea lions changed. Recent studies suggest that fishing pressure near sea lion habitats may contribute to malnourishment and higher mortality of sea lion pups. Fishing restrictions were established around many western Gulf of Alaska islands in 2004 to protect Steller sea lions from extinction. Read more here and here. Explore more of the Chiswell Islands here:

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