TELEMETRY OF HOMING BEHAVIOR BY THE DEERMOUSE, PEROMYSCUS.

Miniature transmitters (weighing 2.5 to 2.7 grams, including encapsulation) implanted subcutaneously in deermice (Peromyscus) radiate a pulsed signal at 27 megacycles per second which can be detected by a simple antenna at a distance of 45 meters. The radio signal indicates movements of the deermice, periods of activity, and the location of occupied nests. One mouse was traced as it returned to its nest 300 meters in 1 hour. This rate of homing is many times more rapid than the rate usually determined by conventional methods for tracking small terrestrial mammals.