Monday, August 4, 2008

PS 13-151: Box turtles in Arkansas: Habitat selection and diet

Gary R. Huxel, University of Arkansas

Background/Question/Methods

Two species of box turtle are present in Arkansas: Terrapene carolina triunguis (three-toed) and Terrapene ornata ornata (ornate).  These two species have different habitat preferences with the ornate box turtle favoring  natural relict prairies and the three-toed favoring grasslands with nearby forested areas.  However, they are occasionally found sympatric.  The loss of native prairies and forests in Arkansas has contracted the available habitat for these species.  Thus, one must ask whether the box turtles are able to persist in suboptimal habitats, and if so, does this effect population dynamics and the status of individuals.

The habitats available differ in available food resources, thus habitat selection may influence diet.  This leads to the null hypothesis that diet does not diet for each species across habitats.  The available food resources and the diet of both species in a variety of habitats has investigated. 

Results/Conclusions

Ornate box turtles have been found in only native or restored prairies that have not been previously plowed.  Three-toed box turtles have been found in prairies and in forested areas.  The diet of three-toed box turtles differs with habitat as does the availability of resources.  As noted in previous studies, these species have differ temperature tolerances and preferences with ornate box turtles favoring warmer conditions.

The Arkansas Natural Heritage Commission along with The Natural Conservancy are preserving and restoring prairie systems in Arkansas.  Given this and predicted warmer temperatures in response to climate change, the ornate box turtle should increase in abundance and distribution in Arkansas.  How three-toed box turtles will fair is largely unknown, but as more of a habitat generalist it is more widespread in its distribution and is expected to be closely linked to changes in forest habitat availability.