Boxed In: Hinge Closing Performance of Ornate Box Turtles (Terrapene ornata)

Author

Gina L. Buelow, Missouri State UniversityFollow

Date of Graduation

Fall 2021

Degree

Master of Science in Biology

Department

Biology

Committee Chair

Day Ligon

Abstract

Turtles are perhaps best known for the bony shells that encase them, a unique morphological trait that provides protection against predators. Many taxa have even evolved the ability to enclose themselves using hinges that can be used to create a seal between the carapace and plastron. I measured the hinge closing force of Ornate Box Turtles (Terrapene ornata) to assess the performance of this unusual yet ecologically important trait. I sampled head-started turtles from Thomson Sand Prairie in the Upper Mississippi River National Wildlife and Fish Refuge and wild turtles collected in northern Oklahoma. To assess the effects of head-starting on predator defense, I compared hinge closure force, behaviors when threatened, and shell morphometrics between the two populations. Wild turtles typically closed immediately and with greater force than head-started turtles. The head-started turtles exhibited bolder behaviors and often were hesitant to seal themselves completely into their shells. Those that were head-started also had disproportionately long plastrons relative to wild turtles, a characteristic that tended to prevent them from creating a tight seal between the plastron and carapace. These results suggest that future head-start efforts should take steps to meliorate maladaptive morphological and behavioral consequences of captivity to maximize anti-predator measures following release.

Keywords

conservation, head-start, reintroduction, animal behavior, turtle morphology

Subject Categories

Behavior and Ethology | Other Ecology and Evolutionary Biology | Zoology

Copyright

© Gina L. Buelow

Recommended Citation

Buelow, Gina L., "Boxed In: Hinge Closing Performance of Ornate Box Turtles (Terrapene ornata)" (2021). MSU Graduate Theses/Dissertations. 3692.
https://bearworks.missouristate.edu/theses/3692