RESPONSE OF WESTERN DIAMONDBACK RATTLESNAKES (CROTALUS ATROX) TO CHEMICAL CUES OF MICE (MUS MUSCULUS) OF DIFFERENT GENDERS AND REPRODUCTIVE STATUS

Eight western diamondback rattlesnakes (Crotalus atrox) were exposed to 6 stimuli: (1) clean, unused bedding; (2) an adult male mouse; (3) an adult lactating female mouse; (4) an adult lactating female mouse with a litter; (5) 2 adult nonlactating female mice, to control for the extra surface area in Condition 4; and (6) a litter of newborn mice. All stimuli were presented in opaque plastic boxes with 18 perforations in each side; hence, chemical but not visual cues were available to the snakes. Our goal was to examine if chemical cues from rodents of different genders, lactating female rodents, and rodent litters influence predatory behavior in rattlesnakes. Results indicated that C. atrox responded to odors arising from adult mice (Mus musculus) with higher rates of tongue flicking than were seen in the control condition, but the 4 conditions involving adult mice did not differ significantly from each other. Neonatal mice did not produce consistently higher rates of tongue flicking than did the control condition.