Skip to main content
ARS Home » Research » Publications at this Location » Publication #248339

Title: Where are the parasites?

Author
item KUTZ, SUSAN - University Of Calgary
item DOBSON, ANDREW - Princeton University
item Hoberg, Eric

Submitted to: Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/22/2009
Publication Date: 11/30/2009
Citation: Kutz, S., Dobson, A., Hoberg, E.P. 2009. Parasites on the Move Across the Climate Changed Arctic. Science. 236:1187-1188.

Interpretive Summary: The Review by E. Post et al. (“Ecological dynamics across the Arctic associated with recent climate change,” 11 September, p. 1355) paid little heed to parasites and other pathogens. The rapidly growing literature on parasites in arctic and subarctic ecosystems provides empirical and observational evidence that climate-linked changes have already occurred. The life cycle of the protostrongylid lungworm of muskoxen, Umingmakstrongylus pallikuukensis has changed (1) and the range of that organism and the winter tick, Dermacentor albipictus have expanded (2). Extremes in temperature and the hydrological cycle, predicted in most climate scenarios, can result in epidemic disease outbreaks in arctic-adapted species such as reindeer and muskoxen, with substantial economic costs (3–7). Similarly, increased frequency and magnitude of flooding might enhance transmission of waterborne pathogens such as zoonotic strains of Giardia, in and between terrestrial and marine systems (8, 9). Parasites whose stages in the environment are buffered by gastropod or insect hosts have the potential to increase in abundance and distribution, whereas for those with life stages that develop freely in the environment, extreme variability in microhabitat temperatures and humidity might reduce their abundance (2, 10). Given the low species diversity of arctic ecosystems, and the potentially reduced immunocompetence of Arctic species (11), these systems may be particularly sensitive to parasitic invasions (2). Invasions will occur primarily through range expansion of more southerly host species, through ongoing wildlife translocations, and increasing pressures for domestic animal agriculture. All will radically alter the existing parasite fauna and lead to parasite-mediated competition between current residents and newly arrived host species. This might in turn lead to the loss of parasite diversity as arctic-adapted hosts and their endemic parasite species become increasingly displaced by competitive interactions.

Technical Abstract: The Review by E. Post et al. (“Ecological dynamics across the Arctic associated with recent climate change,” 11 September, p. 1355) paid little heed to parasites and other pathogens. The rapidly growing literature on parasites in arctic and subarctic ecosystems provides empirical and observational evidence that climate-linked changes have already occurred. The life cycle of the protostrongylid lungworm of muskoxen, Umingmakstrongylus pallikuukensis has changed (1) and the range of that organism and the winter tick, Dermacentor albipictus have expanded (2). Extremes in temperature and the hydrological cycle, predicted in most climate scenarios, can result in epidemic disease outbreaks in arctic-adapted species such as reindeer and muskoxen, with substantial economic costs (3–7). Similarly, increased frequency and magnitude of flooding might enhance transmission of waterborne pathogens such as zoonotic strains of Giardia, in and between terrestrial and marine systems (8, 9). Parasites whose stages in the environment are buffered by gastropod or insect hosts have the potential to increase in abundance and distribution, whereas for those with life stages that develop freely in the environment, extreme variability in microhabitat temperatures and humidity might reduce their abundance (2, 10). Given the low species diversity of arctic ecosystems, and the potentially reduced immunocompetence of Arctic species (11), these systems may be particularly sensitive to parasitic invasions (2). Invasions will occur primarily through range expansion of more southerly host species, through ongoing wildlife translocations, and increasing pressures for domestic animal agriculture. All will radically alter the existing parasite fauna and lead to parasite-mediated competition between current residents and newly arrived host species. This might in turn lead to the loss of parasite diversity as arctic-adapted hosts and their endemic parasite species become increasingly displaced by competitive interactions.