Brief Research Report ARTICLE
Mortality in Three-toed Box Turtles (Terrapene mexicana triunguis) at two sites in Missouri
- 1Saint Louis Zoo, United States
- 2Saint Louis University, United States
Once ubiquitous, North American box turtles are experiencing reductions in abundance and range, but the magnitude of these losses is largely unknown. In Missouri, native box turtles (Terrapene mexicana triunguis and Terrapene ornata ornata) are declining across the state due to anthropogenic disturbances such as urbanization, habitat fragmentation, and vehicle collisions. Through radio-tracking over a period of seven years, we documented the survival of adult three-toed box turtles at two sites in Missouri: Forest Park (urban park) and Tyson Research Center (a protected rural forest). Estimated annual survival of adult turtles in Forest Park was 79% (95% CI: 0.68-0.87) while at Tyson Research Center annual survival was 93% (95% CI: 0.83-0.97). The odds of annual survival for a turtle at Tyson Research Center were 3.5 times that of a turtle living in Forest Park. “Winter kill”, which refers to box turtles found on the surface during brumation or within two weeks of emergence, was the most frequently documented category of mortality in Forest Park. At Tyson Research Center, winter kill was not documented; however, the reasons for most deaths were unknown. These data raise the question about the potential of large urban parks as refuges for box turtles, which we may answer by future studies that compare box turtles living in multiple urban and rural settings. Our preliminary data suggest that even the largest urban parks may not sustain populations of box turtles which has severe implications as urbanization continues to degrade and eliminate box turtle habitat throughout their range.
Keywords: chelonian1, urban ecology2, winter kill3, telemetry4, survival estimate5, brumation6
Received: 21 Aug 2019;
Accepted: 05 Nov 2019.
Copyright: © 2019 Palmer, Brenn-White, Blake and Deem. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Ms. Jamie L. Palmer, Saint Louis Zoo, St. Louis, United States, email@example.com
Dr. Maris Brenn-White, Saint Louis Zoo, St. Louis, United States, firstname.lastname@example.org