Conservation Strategies and Emergent Diseases: The Case of Upper Respiratory Tract Disease in the Gopher Tortoise

Abstract

ABSTRACT We obtained demographic data on more than 60 gopher tortoise (Gopherus polyphemus) populations in Florida before the emergence of upper respiratory tract disease (URTD). We later resurveyed 10 populations to compare demographic profiles at sites where antibodies to Mycoplasma agassizii were detected subsequently and at sites where they were not. We screened for antibodies and checked for potential biases in studying URTD by determining whether individuals caught above ground were representative of a population as a whole and whether the probability of detection of seropositive (plus serologically suspect) individuals is a function of sample size. Some sites with no indication of decline had relatively high percentages of seropositive individuals, and some sites exhibiting substantial population decline had no or low percentages of seropositive individuals; therefore, our results do not unambiguously implicate the presence of URTD in the population declines. Seropositive individuals occurred at 4 ...