Box Turtle Update: A Goodbye

We have to say goodbye to one of the first Eastern Box turtles we decided to research on the Edge.

EOA2 (Hoffa) 2019  Photo by Sam James

EOA 2 (see previous blog post from January 22, 2016) was found expired at the end of November.  This was a few weeks after our first freeze accompanied by the first snow of the season on Nov. 11 2019.  Possibly, this Eastern box turtle, froze to death before getting to its over wintering spot for the season.  But it did turn up the past summer missing a leg, which may have led to complications with movement or infection.  No other visual evidence of attack, disease or fungus appears to be the cause, but freezing is an assumption.  EOA2 was the second turtle we glued a transmitter on in 2014 and have been following its activity for 5 years.

EOA2 out and about flaunting the transmitter on its back.

See EOA2 buried in the soil to the right of a the GPS unit.  This is all the deeper it needs to be to survive winter.

This turtle was visited via telemetry by at least 100 students helping to track its movements. From 2014 until 2019, EOA 2 was followed to better understand the habits of Eastern box turtles on the preserve.  The map below shows the recorded range of the area this turtle moved in 5 years.  It was never found outside the yellow circle on the map which is over 30 acres and a perimeter of almost a mile.  Robyn Wright-Strauss, who has been researching the turtles here commented that this is a much larger range than estimated in publications.  EOA2 liked to move!

On this Northwestern slope of the preserve, the turtle used 2 overwintering spots over the five years, marked as orange dots in the map above.  We learned that it would bury itself shallowly under the leaves in these two depressions in the ground and remain there from November until April.

Multiple locations were documented over the 5 year period

This box turtle was first picked up in the parking lot of the Eulett Center.  It was never found accidentally over the 5 years, but only when we searched for it via radio telemetry.  We have transmitters on other box turtles in the same area, but we have learned the most from this original capture.  We will learn more in the future from the other turtles, but as our first, EOA2 will always be the example of turtle behavior.  For us, this turtle was the leader.

Posted by:  Mark Zloba

Where does an Eastern box turtle go in the winter?

Two years ago, I decided to put radio transmitters on Eastern box turtles to track their movements, and use this as an educational tool with our Science Camps.  These transmitters were leftover from a previous project and had very little battery life left in them.  So instead of throwing them away, I thought it would be a fun way to learn a little bit about box turtle home ranges.  The students use a Yagi antenna and go in search of the turtle, and if found we would weigh it, record its sex and GPS where it was found.  Following individual box turtles has been interesting to say the least.  Sometimes they would not move for over a week, then all of a sudden travel a few hundred yards in a couple days.  Most days we would find the turtle we were after, some days it would be hidden so well that a half a dozen of us could not find it, even though the receiver attached to the antenna was beeping loudly (which meant we were close).



Student using antenna to track box turtles



In the winter of 2014-2015, I was lucky enough to find a turtle (EOA-2 it was labeled, but I call him Hoffa since he is hard to find) buried in the soil in its hibernation spot.  This was great because I had never seen where a turtle chose to spend the winter.  Nor did I know how deep into the ground it would go.  I was surprised to see that not all of the shell is under soil.  It must be deep enough to stay a constant temperature, warm enough to prevent freezing.  It was burrowed in a depressed part of the ground where a tree root had rotted.  The top of its shell was exposed and only leaf litter covered that part.  I don't know how it managed to cover itself with leaves like a blanket.  I guess it was that year's leaf fall from the trees. 

EOA-2 or "Hoffa" getting a new transmitter attached and weighing in at 442 grams

 In April of 2015 Hoffa (EOA-2) came out of his hole in the ground and moved about again.  Throughout the summer, Science Camp students tracked him again, giving us an idea of his home range.   One day, they went in search of Hoffa but they could not hear his "beep".  Each turtle has a frequency number associated with its transmitter that will beep when its number is plugged into the receiver.  And if it gets too far away, over a big hill or the battery dies, you will not hear a beep.  After weeks of searching and listening for the beep, we figured our time with Hoffa was over.  The battery must have died and I figured one day we will stumble upon him and take off the dead receiver.  Months went by and this did not happen.  So goes nature.
 

Some points where EOA-2 traveled in 2 years. Green tacks show where turtle was found.  Range measures 1500 ft. X 500 ft.

A few weeks ago, In December, I was thinking about Hoffa, and where he would hibernate this winter.  Some reptiles, like many snakes, hibernate in the same place each year, could Hoffa do the same?  How specific are box turtles to their winter burrows?  When I got to work, I went to the area he was hibernating in last winter. I re-found a tree that I thought he was near last year, and it had a depressed area where a tree root had rotted.  This was the same area as before.  I raked away some leaves and unbelievably, there was about 2 inches of a turtles shell showing through the soil.  I couldn't believe it, but there was a turtle, in the exact same spot as last year.  I dug a little bit of soil out to see if there was a transmitter, and it was there, still attached.  It was Hoffa.

"Hoffa" buried in the same location as last winter

Now, this may or may not be common knowledge to Herpetologists, but I did not know a turtle would return to the same location each year to hibernate.  At least this turtle did, 2 years in a row.  This March I will put a new transmitter on Hoffa, and hopefully we will get to track him for a third year, and just maybe, he will go back to this same root hole to hibernate.

Posted by: Mark Zloba