26th Annual Meeting and Symposium of the
Desert Tortoise Council, March 16-18, 2001
Abstracts

Status of the Sonoran Population of the Desert Tortoise in Arizona:
Arizona Interagency Desert Tortoise Team

Roy C. Averill-Murray
Arizona Game and Fish Department, 2221 W Greenway Road, Phoenix, AZ 85023

The Arizona Interagency Desert Tortoise Team updated a 1990 report on the status of the desert tortoise in the Sonoran Desert to analyze current management to conserve viable populations of Sonoran desert tortoises. Important gaps in desert tortoise habitat protection occur near Phoenix, Tucson, and Kingman, areas under pressure as more public land is being accessed for recreation by Arizona's growing urban population. Genetic contamination and introduced disease from released captives also pose increasing risks. Wilderness-level status in some areas may offer protection against urbanization, roads and OHV activity, and grazing and mining, but other threats, especially exotic plant invasion and fire, are not constrained by artificial boundaries. Unknown effects of habitat fragmentation may also impact many populations.

Tortoise populations currently appear to be stable within Arizona's Sonoran Desert, but monitoring has been haphazard. Inconsistent funding will result in increased time before trend estimation is possible, and catastrophic declines might not be recognized as such, thus reducing the ability to identify and correct the cause. Unknown significance of cutaneous dyskeratosis within tortoise populations poses another concern. Continued monitoring is essential to better quantify population status and trends. Individual and cooperative efforts by land and wildlife management agencies must continue to ensure that sufficient habitat area and quality remain for survival of tortoise populations. Resources are needed to implement existing policies, update management plans, and enforce existing regulations on public lands. Finally, research is needed to address population dynamics, habitat impacts, and disease, so managers can better direct their conservation efforts.