Meeting Abstract

P3.24  Wednesday, Jan. 6  Prey Preference of the Desert Nightsnake (Hypsiglena chlorophaea): Invertebrates and Prey Size WEAVER, R. E. *; KARDONG, K. V.; School of Biological Sciences, Washington State University weaverr@wsu.edu

Nightsnakes (Hypsiglena chlorophaea) were collected during 2008 from 3 localities in Washington State,maintained in glass aquaria on a 12:12 light cycle, and fed a variety of known prey items. Water was available atall times. We collected odors from 3 possible invertebrate prey species: spider (Tegenaria spp.), scorpion (Paruroctonus borealis), and field cricket (Gryllus spp.). We then compared the responses of snakes to these invertebrate odors to known vertebrate prey odors. Further, to test whether H.chlorophaea can assess the size of potential prey, odors were collected from adult and juvenile garter snakes (Thamnophis spp.). We presented all odors on pre-moistened 13-cm cotton swabs held 2.5 cm in front of a snake’s snout. For each trial we recorded the number of tongue flicks/60 s, and the latency to first tongue flick. There was no significant difference in tongue flicks or latency between either spider, scorpion, or cricket odors to water or a pungency control. Snakes did respond with greater tongue flicks, and a decreased latency to a vertebrate odor over each invertebrate odor and water control. Snakes responded with increased tongue flicks to small snake odors over large snake odors. Our study is the first to show that at least for the invertebrates tested, H. chlorophaea does not exhibit a chemosensory response to these invertebrate prey odors, a result which is supported by current field work. This study is also the first to show that a snake can assess the size of potential prey via an odor stimulus.