The ecology of Echinococcus multilocularis Leuckart, 1863, (Cestoda: Taeniidae) on St. Lawrence Island, Alaska. I. Background and rationale

Abstract

The island, about 5000 km2 in area, is mainly tundra, with a relatively cold, wet climate and depauperate fauna and flora. The principal hosts of E. multilocularis on the island are the arctic fox, Alopex lagopus, and the northern or root vole, Microtus oeconomus, which inhabit most of the area and whose populations are cyclic, with a 3 to 4 year frequency. The study, begun in 1956, comprised a 4 year intensive phase, in which the host and parasite populations and the environment were examined in detail, and an 11 year follow up phase, in which the results of earlier work were repeatedly tested in the field and under laboratory conditions. Primary emphasis was placed on the influence of population cycles of the natural hosts on the abundance of the parasite. Comparative studies of the synanthropic life cycle, involving sledge dogs and voles in the island's largest Eskimo village, also were undertaken.