Identification and Tracking of Juvenile Desert Tortoises

Identification and tracking techniques are required for discovering juvenile Desert Tortoise migration paths at Edwards AFB, and specifically in the PIRA solid rocket plume outwash areas. Now, only the technology for tracking adult tortoises exists, and as a threatened species the juveniles must be included as soon as possible. Although suitable tracking devices exist for insects and small animals, they do not presently simultaneously satisfy battery size, longevity and transmission range for the small tortoise. The proposed research will solve this problem by utilizing a harmonic transponder as a transmitter, either unpowered or with one or more RF amplifiers. Beginning with the 0.915± 0.013 GHz band, a tortoise mounted transmitter and compatible interrogator/receiver system will be investigated and evaluated for detection/identification range. For each RF design, battery size will be evaluated for lifetime vs. output power and the resultant transmitter package evaluated for tortoise compatibility and suitability for the Edwards AFB geography. Innovative antenna and RF hardware concepts are available at Spectra-Research to produce transmitter and interrogator/receiver designs not presently extant. Although not required until Phase II, we will fabricate and test the optimum transmitter design by the end of Phase I.