LNG 2-5 - Eastern indigo snakes discriminate among prey odors and prefer copperheads

Tuesday, August 9, 2016: 10:35 AM
Floridian Blrm BC, Ft Lauderdale Convention Center
Scott M. Goetz, Biological Sciences, Auburn University, Auburn, AL, James C. Godwin, Alabama Natural Heritage Program, Auburn University, Auburn, AL, Fred Antonio, Central Florida Zoo, Sanford, FL and David A. Steen, Auburn University, Auburn, AL

Prey records indicate that the Eastern Indigo Snake (Drymarchon couperi) is a dietary generalist; however, we know little about diet selectivity of this imperiled species. In this study, we investigated dietary preferences using a sample of neonate Eastern Indigo Snakes (N = 55) from 11 clutches by assaying responses to chemical cues from several potential prey species. Specifically, we explored predatory response to cues from a mammal and representatives of two subfamilies of snakes (Colubrinae and Crotalinae). Snakes were presented with chemical cues of potential prey and preference was assessed using a tongue flick attack score using a repeated-measures design. 


We found that Eastern Indigo Snakes exhibited a significant overall preference for snakes over house mice (Mus musculus; P < 0.0001), and a significant preference for Copperheads (Agkistrodon contortrix) over Ratsnakes (Pantherophis spiloides; P < 0.0001). Our results demonstrate prey discrimination in Eastern Indigo Snakes and a preference for ophidian prey. Importantly, our findings indicate crotaline snakes may be a principal dietary component of wild populations. This information increases our understanding of the natural history of Eastern Indigo Snakes, the focus of numerous conservation and repatriation projects.