Orientation and Homing of the Brush Rabbit (Sylvilagus bachmani)

Abstract

A study of orientation and homing in brush rabbits, Sylvilagus bachmani ubericolor (Miller), was conducted on the E. E. Wilson Game Management Area, 7 mi. N Corvallis, Oregon, between July 1967 and April 1969. Sixty-seven individual rabbits were fitted with radio-transmitters and returned to the field. Home ranges were determined for 59 of these animals. Rabbits rarely left brushy cover. Home ranges of males were larger than those of females. Nineteen of the 59 rabbits whose home ranges were determined were displaced in 29 “homing” experiments. No rabbit was displaced more than twice. Rabbits homed successfully in 15 of the 29 experiments. Brush rabbits did not home over distances as great as those reported for other species of Sylvilagus or other small mammals. Homing success was not inversely related to distance displaced as has been reported for other small mammals. Rather, there was a distinct limit above 540 feet beyond which no rabbit homed. A direct correlation was found between distance displaced and homing time; maximum homing time was 36 days. Homing ability was related to size of home range. Brush rabbits usually homed on clear nights; indicating homing depended primarily on sight. No correlation occurred between homing success and season, sex, or age. A significant number of rabbits left the release box in the direction of the nearest cover. Rabbits also restricted their routes of travel to brushy cover while attempting to home. Brush rabbit home ranges decreased significantly in size after first displacements but not after second displacements.