| The Western Pond turtle (Actinemys marmorata) is a mid-sized semiaquatic turtle found throughout Northern California in reservoirs, ponds, and streams. Six perennial stock ponds on East Bay Municipal Utility District lands have persistent Western pond turtle populations that are monitored annually using visual basking turtle counts. A decline in the total number of turtles observed at these ponds annually coincided with California's most recent drought, prompting a mark/recapture study to be carried out during the summer or 2017. A mark/recapture study of similar scope and methodology was previously carried out at one of the monitored locations in 2011 as part of a telemetry effort. Comparing the results of these two studies provides a "before and after" snapshot of turtle demographics in one pond, following a severe drought. This project seeks to gauge effects of extended drought conditions on a turtle population's age structure, physical demographics, survivorship, and breeding capacity by analyzing data collected during the study. A cursory evaluation of capture data indicates a population shift towards a younger, smaller demographic, with population estimates lower than previously recorded. |