Box Turtle Project Update

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Scott Kiester, Friends of LLELA, Elm Fork Master Naturalist

Several years ago, LLELA staff, volunteers and visitors who frequent our trails and restoration areas began a discussion about our box turtle populations. Three-toed and Ornate Box Turtles are both native in Denton County. We all noticed that we seldom encounter box turtles at LLELA, and never any young individuals. Volunteers from the Friends of LLELA, Texas Master Naturalists, and UNT began tracking several wild box turtles on the property and fostering a group of juveniles. It is possible that LLELA has only a remnant population of older Three-toed Box Turtles and it is questionable if we have any Ornate Box Turtles at all, since none have been seen in some time. We don’t understand the reason(s) for this population decline yet, but we hope our tracking project will help us better understand the habitat needs of box turtles at LLELA.

The tracking project follows 11 radio-tagged individuals to determine their habitat and resource needs. We hope to learn about the current population and develop information about the habitat requirements for the juveniles that are to be released on LLELA. Most turtles have a home range, the area where they hang out. The home ranges we have documented vary from less than two acres to about seven acres with an average of around four acres/turtle.

There are two groups being tracked: six individuals on the west side of LLELA, in and around the Cross Timbers forest along the Blackjack Trail, and five on the east side of the property in the scrub forests on the edge of the prairies. We have learned that the turtles in the Cross Timbers have smaller home ranges than the individuals on the east side. We plan to investigate the reasons behind this.  There are a few transient individuals who seem to have a regular pattern of movement over a much larger area. An example is Turtle F1, whose nickname is Gypsy. She wanders through an area of about 30 acres.  

All the turtles will all be dug in and hibernating underground by Thanksgiving and are not likely to move again until mid-April. This will give both the tracking team and the fostering team a welcome break from the daily feeding and watering of juveniles and weekly tracking of the movements of adults.  

Young box turtles are subject to predation from several carnivores, principally coyotes, bobcats, and raccoons. Once a juvenile reaches three to four years of age they are large enough to close up using the hinge on their plastron, the bottom shell, and become mostly predator-proof. Volunteers are rearing 24 juveniles who are one to three years old in outdoor enclosures that approximate natural conditions. They will be released at LLELA when they are large enough to use their defenses. Tracking them after release should provide more data to help us help our turtles.

Turtle locationsAbove: a map of LLELA showing the locations of radio tagged turtles. Each color represents a different individual and each dot is a tracked location. The movements of turtle F1, Gypsy, are the blue dots along the east portions of the Blackjack trail. She has been tracked the longest and has the most location dots. Turtle M2 lives in the center of the property, brown dots on the map. We lost track of him when his radio tag was bitten off in May. Very likely he survived though, as several individuals have bite marks and scrapes on their shells. 

 

Turtle F1F1, Gypsy, on 5/30/2019. Notice the bite marks on her carapace.

 

 

 

 

 Turtle F7

 

 

 

 

 

 

 

F7 on the move, 10/8/2019. The radio tags are placed so they will not hinder activity in any way.

 

 

 

Turtle M7M7 showing the hinge on the plastron and how box turtles can close up their shells.

 

 

 

 

 Turtle M2

                                           M2's radio tag showing the bite damage.

 

If you’re interested in volunteering with this project, contact Ken Steigman, steigman@unt.edu.

Find a box turtle on the trail at LLELA? Please photograph it and record the sighting at our iNaturalist Project.