Clinical Signs of Health, Disease, and Trauma in Desert Tortoises (Gopherus agassizii) During a Long-term Study of Populations and Habitat at a 7.77 square km Study Area at the Desert Tortoise Research Natural Area, Western Mojave Desert, USA

Clinical signs of health, disease, and trauma were collected as part of a long-term research program on Agassiz’s desert tortoises (Gopherus agassizii) at a 7.77 square km plot at the fenced Desert Tortoise Research Natural Area in the western Mojave Desert, USA. Surveys for health, infectious and non-infectious diseases were initiated in 1993, because of an outbreak of infectious upper respiratory tract disease caused by Mycoplasma agassizii, M. testudineum, and possibly herpesvirus (TeHV2). The disease outbreak was discovered in 1988-1989. Moderate to severe clinical signs of upper respiratory tract disease increased over time on four surveys, from 1993 through 2012. Moderate to severe signs of shell lesions (cutaneous dyskeratosis, fungal involvement) varied significantly by year. Moderate to severe clinical signs of healed, healing or moderate trauma varied from 29.8 to 42.3 percent in all sizes of tortoises. Evidence of trauma was best predicted by size-age class of the tortoises with rates increasing as size-class increased.