Tracking Scarce Turtles

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One of the more challenging aspects of surveying for Wood Turtles is that they are so darn good at hiding, and they hide most of the time. Couple that with the fact that they roam thousands of feet from water to forage and are an uncommon species with a patchy distribution and it’s no surprise that even Wood Turtle experts get skunked on quite a few surveys. For new “experts”, the problem is even worse, and from what I have seen it takes most folk about two weeks of looking in the best places before they finally start to figure out how do it. The stages of learning to find Wood Turtles progresses from 1) not having a clue how to find them to 2) knowing where to look, but still not finding any to 3) becoming extremely frustrated at how many Wood Turtles everybody else is finding and thinking you are a natural failure and finally 4) finding Wood Turtles left and right. Go to a spot with a very small population and all bets are off, even for the adept. Last year one of our big priorities was to survey places in Vermont’s Northeast Kingdom where Wood Turtles had never been documented before and where, in all likelihood, population sizes were either zero or not far from it, so we were well-acquainted with the feeling of coming up empty. It was in places such as those where knowing how to identify Wood Turtle tracks tipped the scales ever so slightly in our favor. 

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Two rows of prints spaced evenly apart are a classic trademark of turtle tracks.

Turtle tracks are very unique compared to any other vertebrate. While a muskrat, for example, places one foot almost on top of the other along the midline of its path, the shell of a turtle keeps their feet spaced apart from one another so what you get are two rows of tracks spaced evenly apart moving in parallel (I like to think of turtles as tiny army tanks moving around on the beaches). Furthermore, because in Vermont we really only have three species of turtle in most places (Wood, Painted, and Snapping), it is actually pretty easy to make an educated guess as to which tracks belong to which species.

Painted Turtles very rarely turn up in Wood Turtle streams because they favor standing water, so if tracks are on the banks of a stream you can just about rule Painted Turtles out unless there is an oxbow wetland nearby. Snapping Turtles, however, live in all kinds of aquatic habitats, but get many times larger than Wood Turtles, so size of the tracks help. Their feet tend to be a little fatter compared to the width of the body too, so you can usually make an educated guess even for juvenile snappers. Much more telling, however, is what the tracks are doing. Snappers rarely leave the water for any reason other than laying eggs or basking. Wood Turtles though, move back and forth from water to land many times and sometimes I’ve felt like I’ve followed the tracks of the same turtle for hours as the tracks come out of the water along a beach, then go back in, and then back out on the next beach, and so on for an entire survey.

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Well-hidden, we likely would have ended the survey this turtle was found during had we not located the turtle's tracks first and more thoroughly searched the spot as a result.

With good timing and a bit of luck, it is possible to follow tracks a short distance right to the turtle that left them, but more often than not, simply seeing the tracks iss a clue that if we keep going back to the spot, eventually we will find a turtle. Usually that is true, but not in all cases. I’ve explained the art of turtle tracking to some skeptical folk in the field who were quite surprised to see that you can actually find turtles by following their tracks. But we’ll forgive them for their skepticism, as they were usually mammalogists far along in their careers.

good and bad tracks
Under ideal conditions (left), you can make out the imprint of each scale on the bottom of a turtle's foot, but more often than not tracks can be easy to overlook (right), with only faint markings from the toenails visible.

When the substrate and moisture is perfect you can sometimes even make out the imprint of each individual scale on the bottom of a turtle’s foot. But stream banks can be dry, full of rocks, recently rained on, full of vegetation, or otherwise too hard to leave a long-lasting imprint. Sometimes there isn’t much to go on, like half of a single footprint with just a few scratches from toenails visible. Believe it or not even something so subtle has helped us eventually hone in on a previously unknown population. 

three-legged turtle and tracks
Prints spaced twice as far apart on one side as the other is a good indication that the turtle who left them is missing a limb.

And sometimes the tracks tell a story. Follow them long enough and you can figure out if the turtle was foraging, looking for a nest site, “out for a morning stroll” as I like to put it, or just headed somewhere. You can also get a feel for how many juveniles are out there based on track size, and sometimes it is even possible to identify individual turtles based on the tracks if they are missing some digits or better yet, a whole leg (better for tracking, not for the turtle, obviously).

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During late spring, female Wood Turtles spent lots of time picking out the right spot to lay their eggs, leaving behind tracks that zigzag back and forth across the nesting beaches.

I recall one landowner who said he’d lived on-site for 45 years and if there were orange-legged turtles on his farm he’d know about them. Documenting a Wood Turtle in that area was important, but after the first season I’d only seen one set of tracks and zero turtles, so I kept at it the next season and eventually found two old male turtles near where the tracks had been the year before. The true irony was that those two turtles had probably been on the farmer’s land longer than he had. Thankfully he was home that day so I could show him one of the turtles, but regrettably he was no longer flexible enough to actually put his foot into his mouth.

Tracks25 - new location
After three surveys, these tracks were the only evidence we had that Wood Turtles occurred on site, but the tracks prompted us to try again the next year, resulting in the known range of Wood Turtles in Vermont being extended a distance spanning several towns.

Finding Wood Turtles can be very hard, but folk who work with the species become pretty good at it, and knowing how to identify their tracks is a very big part of that process. You don’t need to know how to track a turtle to find them in the hotspots, but if you want to find one in a place where they have never been documented and are most likely incredibly scarce, tracking is paramount to a successful field season.