Date of Award
Doctor of Philosophy (PhD)
College of Science and Mathematics
Earth and Environmental Studies
Thesis Sponsor/Dissertation Chair/Project Chair
Snapping turtles--Mercury content--New Jersey, Diamondback terrapin--Mercury content--New Jersey, Turtle fisheries--Law and legislation--New Jersey, Wildlife as food--Health aspects, Health risk assessment--New Jersey
Snapping turtles and diamondback terrapins have unique life characteristics, making their populations’ survivorship heavily dependent upon the turtles that reach sexual maturity, limiting the harvest potential of turtles and making them vulnerable to exploitation. Therefore, this research tests mercury concentrations in diamondback terrapins and snapping turtles to determine if turtle meat should require human consumption advisories, and examines transport of mercury through the snapping turtle food web by testing prey items for mercury burden and mapping food webs using stable isotope composition.
Consumption of New Jersey diamondback terrapins and snapping turtles pose a health risk. 25% of Cape May and 46% of Meadowlands terrapin muscle samples surpassed the U.S. Environmental Protection Agency mercury threshold for fish consumption. For snapping turtles, Lake Wapalanne had the highest percent of turtle samples surpassing the threshold (36%), followed by Kearny Freshwater Marsh (33%) and Lake Hopatcong (28%). Based on the results of this study it is crucial to implement human consumption advisories for consumed turtle species.
Neither the commercial or recreational harvest of snapping turtles in New Jersey is well understood. We therefore administered a survey to learn about current harvest practices, willingness of commercial and recreational harvesters to pay increased license fees, and their willingness to comply with new regulations.
Respondents to the recreational harvest survey collected approximately 2,285 snapping turtles between 2012 and 2014. Respondents from the commercial harvesting survey reported collecting 1,506 turtles during the 2014 season. Commercial harvesters are willing to pay a higher permit price, up to $29.22, to keep their harvesting privileges.
The results of this study suggest diamondback terrapin and snapping turtles pose a human consumption health risk due to elevated mercury concentrations. We suggest consumption advisories be developed for snapping turtles starting with locations of heavy harvest while advising the sensitive population to avoid the consumption of turtles. Based on the results of the harvest surveys we can suggest both recreational and commercial harvesters are willing to follow regulations in order to ensure future harvest. Harvesters are also willing to pay a higher permit price to keep their current harvesting privileges.
Sherwood, Natalie R., "Risks Associated with Harvesting and Human Consumption of Two Turtle Species in New Jersey" (2017). Theses, Dissertations and Culminating Projects. 46.