The influence of chemical cues on burrow choice by desert tortoises (Gopherus agassizii) was examined using a series of four two-choice tests of treated and untreated artificial burrows. A total of 32 adult tortoises (16 males, 16 females) were tested during nesting and mating seasons. Treatments included feces from an adult male, feces from an adult female, feces from the subject tortoise, and chin-gland secretion collected from an adult male tortoise, When presented with chin-gland secretion, male tortoises spent more time inside the treated than the untreated burrow during observations, and significantly more males used the treated burro tv during the mating season. In addition, males were less likely to use the treated burrow when the treatment was another mate's feces. During the nesting season, significantly more females used the untreated burrow when the treatment was another female's feces. Feces and chin-gland secretion deposited in the vicinity of burrows malt influence burrow use patterns by free-ranging desert tortoises.
