28th Annual Meeting and Symposium of the
Desert Tortoise Council, February 21-23, 2003
Abstracts

Spring, Fall, or Winter? Success of Desert Tortoise Translocation as Affected by Season of Release

Kimberleigh J. Field^1,4, C. Richard Tracy¹, Philip A. Medica^2,5, Ronald W. Marlow¹, and P. Stephen Corn^3
1Biological Resources Research Center, University of Nevada-Reno, Reno, NV 89557;
²USGS Biological Resources Division, Las Vegas, NV 89108; 
³Aldo Leopold Wilderness Research Institute, 790 E. Beckwith Avenue, PO Box 8089, Missoula MT 59807; 
⁴Arizona Game and Fish Department, 2221 W. Greenway Road, Phoenix, AZ 85023
⁵U.S. Fish and Wildlife Service, Southern Nevada Field Office, 4701 N. Torrey Pines Drive, Las Vegas, NV 89130

Translocation gives numerous desert tortoises in Clark County, Nevada a second chance. Urban expansion is displacing tortoises at an alarming rate. Prior to our experiments in translocation, tortoises collected from the wild were kept in pens at the Desert Tortoise Conservation Center in Las Vegas with no plans for them to become functioning members of recovering wild populations. Numerous variables may affect the success translocation. In this experiment we investigated the effects of season of release on mortality, movements, and body mass of desert tortoises. Tortoises were translocated to the Large Scale Translocation Study (LSTS) site near Jean, Nevada in spring 1998, fall 1998 and winter 1999. The results of this study allow us to determine the most suitable times for translocation to occur. Considerations such as cost of maintaining tortoises in captivity prior to translocation may also affect decisions and should be considered in concert with expected mortality rates, behaviors, and changes in health status following translocation.