The Mojave desert tortoise (Gopherus agassizii) is federally listed as a threatened species north and west of the Colorado River under the Endangered Species Act. Desert tortoise monitoring will assist researchers in estimating population density. Monitoring occurs during April and May to coincide with the peak activity season of desert tortoises. Field Crew Supervisors will be required to demonstrate proficiency in backcountry wilderness field skills including but not limited to 4WD vehicle operation, field safety and emergency response protocols, proficient use of GPS and electronic data collection technologies, as well as navigation using topographic maps and compasses. In addition, Field Crew Supervisors will be field tested on their ability to follow monitoring protocols thor