A Population Model for the Diamondback Terrapin: Implications for Conservation Management

The diamondback terrapin, Malaclemys terrapin, is an estuarine turtle important in the conservation of the Chesapeake Bay. This paper presents a discrete-time matrix model for the terrapin population. The model was analyzed in order to increase understanding of terrapin population dynamics and to determine the effects of various population pressures, including crab potting, road mortality, and nest predation. It was found that the survival of a population is most greatly affected by adult female mortality. However, the capture of juvenile terrapins as by-catch in the crab potting industry was also found to be a major threat to the survival of the diamondback terrapin. I also analyzed how the disproportionate capture of males in crab pots affects gender ratios and long-term population growth. The results of this model have implications for both research and conservation management for the diamondback terrapin