Among Alaskan mammals examined for helminthic parasites during 1950 was a series of marmots, Marmota caligata broweri (Hall and Gilmore, 1934) from the Brooks Range, Arctic Alaska. The animals were collected a few miles south of Tolugak Lake (lat. 68Â° 24' N., long. 151Â° 26'W.), and from the vicinity of Kanayut Lake, about 15 miles northeast of Tolugak Lake. This distinctive marmot has been hitherto represented in collections only by the three specimens comprising the type material. In addition to greatly extending the known range of this form, the collection of these specimens also contributes the first information on Brooks Range marmots (Rausch, 1950).
Helminth parasites of rats have been investigated in many parts of the world; however, no previous investigations of the parasites of this host have been made on the Aleutian Islands. Because rats are implicated in the transmission of various diseases to man, a knowledge of rat parasites is fundamental. The purpose of the present study was to obtain information concerning the helminth parasites of Adak rats and to determine, insofar as possible, the occurrence of related health problems. This study was conducted on Adak during May 1950 in conjunction with animal-borne disease investigations by the Arctic Health Research Center, U.S. Public Health Service, Anchorage, Alaska.
A survey of the helminth parasites of Alaskan rodents has been carried on by the writer since the winter of 1948-49, as a continuation of an investigation begun in the central United States in 1942. Results of this work indicate that, despite the size of the Territory of Alaska, the survey is complete enough to furnish a reasonable knowledge of the species of helminths parasitic in microtine rodents in Alaska. Information derived from previous investigations serves as a standard against which the completeness of the present work may be judged. In the writer'sopinion, the continuation of this work on a survey basis is impractical, and it is the purpose of this paper to report qualitatively the results obtained to date. Main emphasis has been placed here on the taxonomic consideration of the helminthspecies collected. Ecological and zoogeographical observations will be presented in another publication.
During the spring of 1951, the U.S. Fish and Wildlife Service undertook the removal of sea otter, Enhydra lutris (L.), from the Aleutian Island of Amchitka, for the purpose of restocking range from which the animals have long been exterminated. The decision to undertake this activity was influenced by the nature of military operations planned for the island later the same year. The capture and removal of the otter were under the supervision of Mr. Robert D. Jones, Biologist, U.S. Fish and Wildlife Service. Heavy losses among the animals shortly after capture made the venture unsuccessful. Many deaths were concurrent among animals in the wild state. The writer was asked to investigate the causes of disease in the sea otter, and it is the purpose of this paper to report the results of these investigations.
References concerning the diseases and parasites of ptarmigan are widely dispersed in the literature, and for the most part are not readily accessible. It is the purpose of this paper to report the helminth parasites obtained from 191 willow ptarmigan, Lagopus lagopus (Linn.); 45 rock ptarmigan, L. mutus (Mont.); and 56 white-tailed ptarmigan, L. leucurus (Rich.). These birds were collected over a period of four years, and were taken from widely separated areas in Alaska.
According to the work of Rausch (1953) , two species of helminth parasites, Porrocaecum decipiens (Krabbe, 1878) and Microphallus pirum (Afanas'ev, 1941), are pathogenic for the sea otter, Enhydra lutris (L.) , on the Aleutian Island of Amchitka. In continuation of investigations of sea otter mortality on Amchitka during the latter part of May and early June, 1952, the writer made an attempt to
obtain information on the life cycles and developmental characteristics of these parasites. It is the purpose of this paper to report the results of these observations.