Ecological epidemiology of an invasive host generalist parasite, Dicrocoelium dendriticum, in Cypress Hills Interprovincial Park, Alberta
Beck, Melissa A.
University of Lethbridge. Faculty of Arts and Science
Lethbridge, Alta: University of Lethbridge, Dept. of Biological Sciences.
Innate variability in parasite transmission is one of the hallmarks of the phenomenon of parasitism. Empirical research aimed at quantifying these differences is limited, particularly for generalist parasites that utilize a broad range of sympatric hosts. Using an ecological epidemiological approach, I characterized variability in transmission of an emerging host generalist parasite, Dicrocoelium dendriticum, in Cypress Hills Interprovincial Park, Alberta. ‘Hotspots’ for ant-to-ungulate transmission were characterized by the presence of aspen (Populus tremuloides) trees on moderately graded, south, or east facing slopes at elevation > 1300m. Individual fluke performance and per capita fecundity were approximately equal among naturally-infected elk and experimentally-infected sheep and cattle. However, when these data were combined with host population size and host residency time in CHP, the sub-population of roughly 4000 cow/calves that are pastured in CHP contribute approximately 80% of the estimated 300 billion eggs that contaminate pasture each year.
ant-to-ungulate transmission , environmental factors , GIS-based analysis , host-specific factors , parasite distribution , parasite spill-over