Physical Sciences and Mathematics Commons^™

Visual Head Counts: A Promising Method For Efficient Monitoring Of Diamondback Terrapins, Patricia Levasseur, Sean Sterrett, Chris Sutherland

Environmental Conservation Faculty Publication Series

Determining the population status of the diamondback terrapin (Malaclemys terrapin spp.) is challenging due to their ecology and limitations associated with traditional sampling methods. Visual counting of emergent heads offers a promising, efficient, and non-invasive method for generating abundance estimates of terrapin populations across broader spatial scales than has been achieved using capture–recapture, and can be used to quantify determinants of spatial variation in abundance. We conducted repeated visual head count surveys along the shoreline of Wellfleet Bay in Wellfleet, Massachusetts, and analyzed the count data using a hierarchical modeling framework designed specifically for repeated count data: the N-mixture model. …