Leech Parasitism in a Turtle Assemblage: Effects of Host and Environmental Characteristics
Leeches are one of the most commonly observed parasites of freshwater turtles. We used baited hoop traps to capture 433 turtles belonging to five species (Apalone spinifera, Chelydra serpentina, Chrysemys picta, Sternotherus odoratus, and Trachemys scripta) to determine the host (species, microclimate use, sex, reproductive stage, and body size) and environmental characteristics (month of capture, turtle abundance, vegetation, turbidity, pond size, and availability of basking structures) that affected leech parasitism in Illinois ponds. Leech prevalence on turtles varied significantly among turtle species, was highest on bottom-walkers and adults, and varied throughout the year. Leech intensity was highest on larger turtles and in turbid ponds. The results from this study display the importance of utilizing turtle assemblages for examining overall trends in host–parasite dynamics, demonstrate the influence of environmental characteristics on leech parasitism, and provide baseline data for future studies examining leech parasitism on turtles.Abstract
Frequency histogram of the number of leeches on each turtle species. Each bar indicates the percentage of turtles of each species that had leech intensities within the numerical category.
Leech attachment sites for each turtle species. Each symbol represents the prevalence of leeches at that site for each turtle species. Only one Apalone spinifera was parasitized by a single Placobdella sp. on the plastron and was not included in this graph. Error bars represent 95% confidence intervals.
Prevalence and intensity of leeches on each turtle species. Error bars represent 95% confidence intervals.
Prevalence and intensity of leeches on turtles by month. Data from all five turtle species were pooled. Error bars represent 95% confidence intervals.
Contributor Notes
Section Editor: G. Haenel.