Adult Survivorship and Capture Probability of The Common Snapping Turtle (Chelydra Serpentina)

Abstract

There are currently few harvest regulations for the Common Snapping Turtle (Chelydra serpentina) in West Virginia. Uncontrolled harvest of long-lived species with delayed sexual maturity may lead to long-term declines in populations. We analyzed a 17-year data set from a mark-recapture study on an unharvested population of the Common Snapping Turtle in Canaan Valley, West Virginia. We captured 91 snapping turtles (47 female, 44 male). Program MARK was used to analyze 10 competing models predicting adult Common Snapping Turtle survival and capture probabilities and compared the models using Akaike Information Criterion values corrected for small sample size (AICc). The estimated annual survival was 0.97 and the annual capture probability was 0.11. We found that the best performing model involved constant survival and capture probability that varied based on the mass at initial capture. This suggests that there is no difference in survival between males and females. Moreover, the size of trap may affect the capture of smaller and larger individuals and researchers should use multiple trap types to assess turtle abundance.