The center of abundance for breeding black-legged kittiwakes in the Gulf of Alaska is in the Semidi Islands, where Palmer Sekora (U.S. Bureau of Sport Fisheries and Wildlife 1973) estimated that there were 426,000 breeding kittiwakes in 1972. He located kittiwake colonies at eight sites, ranging in size from 1,000 to 109,000 nesting birds. The size of the average colonial site was 27,000 birds. Ten sites were Class IV in size and one was a solid Class V.
The easternmost known colony in the northern Gulf of Alaska is at Wingham Island. Up to 1973, 22 colonies had been located in Prince William Sound. The largest of these contained only 5,636 nests in 1972 (Isleib and Kessel 1973). Class IV or larger colonies are found at Cape Resurrection, the Barren Islands, Chisik Island, Boulder Bay and Cape Chiniak on Kodiak Island, and at Delarof Harbor and the Haystacks in the Shumagin Islands. It is interesting to note that Gabrielson (1940) considered Whale Island to be one of the largest known kittiwake colonies in Alaska. He stated that there were many thousands of pairs extending over a mile or more of cliff. He saw a second site which he did not visit but looked equally large. A photograph in an article by East (1943) also indicated the presence of a large colony. C. J. Lensink (personal communication) estimated that there were about 100,000 kittiwakes in the colony in 1956. When last visited by Vernon Berns (personal communication), this colony contained only 3,000 birds. It is also of interest that Gabrielson (1940, 1944) did not notice either the kittiwakes or the murres now breeding on Nord Island in the Barren Islands or the kittiwakes on East Amatuli Island.
Whale Island and possibly the colonies in the Barren Islands give evidence of local population fluctuations, but for the most part I have not found an indication of a major perturbation over the past 40 years. Before 1936, the record is too fragmentary to allow an assessment.
One of the interesting aspects of kittiwake ecology in the Gulf of Alaska is the common occurrence of breeding failure. David Snarski (December 1943 Quarterly Progress Report, Alaska Cooperative Wildlife Research Unit, University of Alaska) observed breeding failure on colonies in the Tuxedni National Wildlife Refuge in 1970 and 1971 and obtained circumstantial evidence of another failure in 1972. In 1973 all of the breeding cliffs were occupied and nesting was successful. Whatever the cause of these periodic failures, they do not yet appear to have had a permanent impact that we are able to measure.
Red-legged Kittiwake (Rissa brevirostris)
Red-legged kittiwakes are not now known to breed in the western Gulf of Alaska. Turner (1886) stated that he saw a few at Sanak in 1878. We also have Stejneger's (1885) statement, that "red-legged" kittiwakes nest from Bering Island to Sanak. Friedmann (1937) reported two humeri from Kodiak Island middens. During the summer of 1976, two birds were observed off Kodiak Island by Irving M. Warner (personal communication), and one at 158°W and 54°30'-54°20'N south and east of the Shumagin Islands (Patrick J. Gould, personal communication).
Turner (1885) listed the red-legged kittiwake as abundant and breeding in the Near Islands. Turner (1886) also stated that he had seen quite a number about a cliff back of the village on Akutan Island in 1878. He added that to the westward this kittiwake was more abundant than the black-legged kittiwake. Murie (1959) expressed the opinion that Turner had confused the short-billed gull with the "short-billed" kittiwake. Clark (1911) also reported that he had seen the red-legged kittiwake in small numbers near Unalaska and that they became progressively more common west to the Near Islands. Nelson (1887) reported seeing large numbers of red-legged kittiwakes at Unalaska. Murie (1959) and Gabrielson (1940, 1944) did not see any red-legged kittiwakes in the Aleutian Islands. The species has recently been discovered breeding at Buldir and Bogoslof islands (G. Vernon Byrd, personal communication).
Is it possible that we have here another species which is exhibiting a response to some unknown long-term perturbation? The suggestion that such an event has occurred is faint, but it is there. Do we have in the red-legged and black-legged kittiwakes an example of yet another congener pair that has been affected by some perturbation in which one was affected positively and the other negatively? Clark (1911) reported small numbers of black-legged kittiwakes to go with large numbers of red-legged kittiwakes in the Near Islands, which is the reverse of the current situation.
Arctic Tern (Sterna paradisaea)
Gabrielson and Lincoln (1959) attribute to the Arctic tern the most extensive range of any Alaskan water bird. It is found in suitable habitat everywhere north of Tracy Arm in Southeastern Alaska. Murie (1959) stated that he found it nesting at suitable sites everywhere he went. Isleib and Kessel (1973) considered it to be an abundant breeder in Prince William Sound and along the northern Gulf Coast.