Meeting Abstract

P3.7  Friday, Jan. 6  Behavioral Thermoregulation and its Role in Decreasing Morbidity and Mortality Associated with Chytridiomycosis GANTZ, JD*; SHEAFOR, BA; Miami University; University of Mount Union

Chytridiomycosis, an amphibian disease caused by the chytrid fungus Batrachochytrium dendrobatitis, has been implicated as a cause for contemporary precipitous declines in amphibian populations worldwide. Temperature has been shown to be a prominent factor in viability and virility of B. dendrobatitis. Temperatures above 28° C inhibit growth and can be lethal to the fungus while temperatures between 6 and 23° C appear to increase its fecundity. Amphibians which have significant thermoregulatory control due to the thermal variability of their microhabitat, such as tree frogs (genus: Hyla), may be capable of overcoming infection through basking behavior modification and increased exposure to elevated temperatures. In order to test such responses, two species, gray tree frogs, Hyla versicolor, and green tree frogs Hyla cinerea (H. versicolor, n = 9; H. cinerea, n = 11), were selected. Frogs were housed in a 1.83 meter long clear acrylic tube within which a temperature gradient, from 14° C to 35° C, was established, in two separate treatments, uninfected and infected. A non-contact, infra-red thermometer was utilized to record body temperatures six times a day for 5 d. A significant difference between the basking temperatures of the two species existed prior to infection regimes (H. versicolor, mean: 28.0° C, standard deviation: 2.8; H. cinerea, mean: 28.7° C, standard deviation: 2.5). Data collected following the infection regimes was incomplete, as the organisms never displayed definitive signs of infection. In spite of this, the investigation may still provide greater understanding of the mechanisms by which some amphibian species avoid population declines due to chytridiomycosis.