Prevalence and Levels of Parasitemia of Hepatozoon sp. (Apicomplexa: Adeleorina) in Four Gopher Tortoise (Gopherus polyphemus) Populations of South FLORIDA, USA.

Hepatozoon prevalence (occurrence) and parasitemia (intensity) levels were documented in 67 individuals of the threatened gopher tortoise (Gopherus polyphemus) for the first time in four South Florida, US, locations: Jonathan Dickinson State Park (JDSP), Pine Jog Preserve (PJP), Florida Atlantic University Preserve (FAUP), and Blazing Star Preserve (BSP). Sex ratios (males:females) per site were 0.44 at JDSP, 0.72 at PJP, 1.42 at FAUP, and 0.40 at BSP, but no significant differences in the carapace length were found between the two sexes (independent t-test; P=0.101). Hepatozoon sp. was found in 13% (9/67) of tortoises. Percentages of infected tortoises were 22% (5/23) males and 6% (2/33) females. Prevalence and parasitemia were low or nonexistent within sampled tortoises at each of the study sites, although the highest prevalence and parasitemia values were found in gopher tortoises at JDSP (23%, 4/17) which also harbored the highest infection levels, reaching 349/10,000 erythrocytes. No infection was detected within sampled gopher tortoises at PJP.

A Survey of Gopherus polyphemus Intestinal Parasites in South Florida.

Gopherus polyphemus populations are diminishing throughout their range due to urbanization, fragmentation, and poor habitat management. Increased population densities, poor habitat quality, and lack of fire may influence disease transmission. Parasite roles within wild tortoise populations are largely unknown; despite evidence these pathogens may pose significant health risks. This study provides a baseline of gopher tortoise intestinal parasites across South Florida and reports on how varying environmental and tortoise characteristics may affect intestinal parasite species prevalence and approximate loads. Tortoise fecal samples were taken from six tortoise populations across five South Florida sites. Seven species of intestinal parasites were discovered from 123 tortoises. Identified parasites include endohelminths such as cyathostomes, pinworms, ascarids, flukes, and protozoans including Eimeria, Cryptosporidium, and Amoeba species. Significant differences in parasite prevalence and loads were seen between sites, while parasitism among sex, size class, and habitat type remained relatively ubiquitous.