Submitted to: Parasitology Today
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/18/2000
Publication Date: N/A
Interpretive Summary: Although we understand much about the biology of high-latitude ruminants, our knowledge of their parasite fauna is incomplete, even for fundamental issues. Such is consequential, as ruminants, particularly caribou and muskoxen, are keystones for maintenance of remote communities across the North. Accurate documentation of faunal diversity is vital for understanding diseases processes in ruminants, factors associated with parasites as potential regulators of host-populations, and the complex abiotic and biotic parameters that control the distribution, epidemiology and emergence of parasitic diseases. Hidden diversity in the Arctic has been dramatically illustrated by a series of recent discoveries of new genera and species of nematodes in ruminants. Because of recent changes in climate and human activity in the Arctic, our inadequate knowledge of these parasites is critical as it hinders understanding potential impacts of parasites in both wild and domestic hosts. Research on an enigmatic lungworm, Umingmakstrongylus, has served as a model for monitoring and perhaps predicting the effects of climate on parasite development and distribution in northern ecosystems.
Technical Abstract: Ruminants, particularly caribou and muskoxen, are keystones for maintenance of remote communities across the Arctic. Given the importance of these ruminants as food and cultural resources, we have a limited understanding of parasite biodiversity, and the role of lungworms and other nematodes as potential regulators of host populations. In this regard, basic research on Umingmakstrongylus, a lungworm in muskoxen has fundamentally altered some of our ideas about the parasite epidemiology for protostrongylid nematodes in ruminants. Characterized by high prevalence, infections of high intensity, a long life span for adult parasites, an extended patent period, and high rates of larval shedding, this nematode appears well adapted to the Arctic. These attributes, and the observation of a narrow window for development and transmission in the summer, point to limitations on transmission in ephemeral and unpredictable environments. Knowledge of the lifehistory of this parasite derived from experimental studies in the laboratory and on the tundra are the cornerstone for using this host-parasite system as a model for predicting potential biotic responses to global climate change. Elevated temperatures such as those currently observed in the Arctic may increase rates of larval development and broaden seasonally defined windows for transmission. Such perturbations may result in changes in geographic distribution, prevalence and intensity of infection, ultimately having an influence on demographics of northern ruminants.