Meeting Abstract

P2.144  Sunday, Jan. 5 15:30  The influence of prey size and abundance on patterns of energy allocation in watersnakes CHAMBERLAIN, J/D*; GIFFORD, M/E; Univ. of Arkansas, Little Rock; Univ. of Arkansas, Little Rock jdchamberlai@ualr.edu

Fat is utilized for a variety of functions within the body including growth and reproduction. Variation in fat storage and use is predicted to be a function of prey availability and size. Energetic demands often change throughout the year and are associated with reproductive activity. Spatial variation in the availability and size of prey could drive population-level differences in patterns of energy allocation. In this study we test the hypothesis that prey availability will influence the amplitude of annual fat-cycling and reproductive output in diamondback watersnakes (Nerodia rhombifer). We studied watersnakes from four sites that varied in prey size and abundance (two fish farms producing large prey, one fish farm producing small prey, and one lake site with variable prey size and abundance). For annual fat-cycling and reproductive activity, we measured fat-body, liver, and gonad masses of 20 individuals (10 of each sex) from each population at three different time periods (April/May, July/August, and September/October). We also sampled approximately 20 pregnant females from each population to examine reproductive traits. Preliminary data suggest that both reproductive output and patterns of annual fat cycling vary among populations.