A Day With Hatchling Eastern Box Turtles
Release Date: Jan 28, 2014
Contact(s): Kate Salm
There are 57 species of turtles found in the US and 10 of those are found in Michigan. Many species are in trouble because of road mortality, habitat loss and over collection. I got to spend a few days getting to know one of those species, the Eastern Box Turtle for a few days this past summer.
The Eastern Box turtle is the focus of a monitoring project being conducted as part of a partnership with Grand Valley State University (GVSU) in Allendale, MI and the Huron-Manistee National Forests. For the past 3 years Patrick Laarman, a graduate student from GVSU and seasonal wildlife technician for the Forest Service, has spent April through October tracking adult turtles, protecting nests, and waiting for eggs to hatch.
I didn’t know what to expect when I agreed to help Patrick get some video footage and photos of hatchling Eastern Box Turtles for the monitoring. I knew that the hatchling turtles would be adorable, they are baby turtles after all. And I knew that I would be outside. And that was about it. I had no idea how you attach a radio to a baby turtle, let alone what else went along with attaching a radio to a baby turtle. And it turns out there is a lot more involved than just putting a radio on a turtles back. And a lot of reasons why the turtles get radios.
During May and June the female turtles come out of the woods and find a spot they like, dig a hole in grassy forest openings, and then lay their eggs in the hole before covering the eggs up with dirt, usually in the middle of the night. During that time, Laarman and several volunteer undergraduate students from GVSU wait quietly in the dark, listening as raccoons and other predators circle the fields hoping for a chance to snatch the eggs from the nests.
After the female would leave, the students would put a mesh box over the nest to protect it from larger predators in search of a quick meal. When the nests were due to hatch, Laarman enters into a 45-day vigil of nest daily nest monitoring.
I spent two of those days with Patrick, checking nests to see if racoons or ants had gotten the eggs, and seeing if any eggs had hatched. The first day we found one nest with three hatchlings, which were weighed and measured to make sure they were large enough to get a radio. The radio transmitter, about the size of a tiny mint, is glued to their shell with a special non-toxic epoxy that will keep the radio in place for at least a few months. After the glue dries the turtles are put back in the area of their nesting box and released. Then we all stand back to watch they slow walk away.
Each turtle equipped with a radio is assigned a unique radio frequency signal. Laarman uses a radio receiver to pick up the signals, which helps him locate the turtles and identify them. The information provided lets researchers know how far the hatchlings travel after they leave the nest and what types of habitat they use. As the turtles with radios get older, the small radios are replaced by larger ones, placed in a way that doesn’t interfere with the turtles travels.
As you might guess, finding a baby turtle with a radio receiver is as hard as it sounds. Finding the adult turtles, which are much larger than the hatchlings, is also difficult. On one of our monitoring days, I got the chance to help locate an adult turtle with the telemetry receiver. As you walk, the receiver beeps at you giving you an idea of where the turtle may be found – or not found. The louder the beep, the closer the turtle.
Which sounds simple, except the adult turtles blend into their surroundings because of their shell coloring and markings, and they hide under logs, behind trees, and under branches. We had one adult turtle we walked past five times before we found her under a log, in some grass. The babies were even harder to find because they are mostly dirt brown and bury themselves under the top layer of grass and dirt, and they are the size of a wireless computer mouse.
So why all this effort to monitor the turtles? The adult turtles that have had radios attached let Laarman get information about the adult’s habits; where they prefer to spend their time, for the females he finds out nesting site preferences, and even how far the turtles travel over the course of a year or two. Patrick can track about 15 turtles on an average day, which he does several times a week, if possible, from May to October. Each time he finds one he takes a GPS coordinate of where the turtle is and collects many habitat variables, such as the temperature of the air and soil, and a location description, if they are near a tree, under a log or out in the open. After days of collecting habitat data and nesting information, Laarman populates a habitat model, which can be applied to other geographical areas to estimate the chances that there are Eastern box turtles in that habitat.
The monitoring information will be used in the next step, developing an environmental analysis for the area the turtles are nesting in, and deciding how to manage openings, especially openings where the turtles are nesting. Because so many other species, including turkey, deer, bluebirds, butterflies and many other pollinators, also use these openings for nesting and foraging, maintaining and creating openings is essential.
The other thing I found out about turtles on those days, besides learning how to weigh and measure a baby turtle, attach radio transmitters, track a turtle and why all of that is good information to have - if you move a turtle off of the road, put it on the side of the road it was heading towards. Don't move it out of the area where you found it, if you move it out of its area to “rescue” it, you probably aren’t doing it any favors. It will just have to walk that much further to get home again.