On the Personality of “Bruce” the Wood Turtle

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When monitoring populations of turtles, it is common for researchers to use microchips, shell notches, or reference photos to assign unique IDs to individuals. However, if you ask those researchers to tell you about some of their favorite turtles from over the years, they are unlikely to list them by ID number, but rather by name. While there is some debate about whether naming animals in field studies can introduce bias or unduly anthropomorphize them, it seems inevitable that once field biologists get to know wild animals as individuals, some will eventually end up with nicknames. For example, Lady, a Blanding’s Turtle in New York, was first found as an adult in the early 2000s and still nests at the same site every year. Pants is a Wood Turtle a colleague first found in Central Vermont in 2006 (under a pair of pants he had hung up to dry), and is still seen regularly today, fifteen years later. When it comes to the Wood Turtles from our monitoring sites, I might hesitate in choosing my favorite, but the one nicknamed Bruce is certainly in the running, and he’s usually not very hard to find. 

Bruce has overwintered at the same site every winter since we first found him in 2018, and our first glimpse of him each spring is always on or near this grassy bank where he basks.

We first found Bruce on October 14, 2018, as Wood Turtles began congregating near their instream hibernacula. While I did not commit his original sighting to memory, my notes recount that he was a difficult turtle to weigh and measure. Rather than hide in his shell, he kicked, struggled, and basically tried to fight his way back to the stream. This is not too unusual, but also not the species norm. Measuring about 8.5 inches long and weighing in at 2.3 pounds, Bruce is not the largest or heaviest Wood Turtle, but is easily recognized by a small hole in his shell above his tail, so when we spotted him basking again on October 22 and 25, we recognized him immediately and left him be. At that point, he was still just turtle #VT-M-069, but once we started encountering him regularly the following spring it became clear that he has a fairly strong presence along his stretch of the river. 

Every time a turtle is observed on a survey, we attempt to capture it to record measurements and take reference photos of the shell. Bruce is a bit unusual in that his head and legs are out in every single reference photo, whereas most others hide in their shell while being measured and photographed.

Male Wood Turtles compete with each other for mates, and although there may be dozens or more adult males using a given stretch of prime stream habitat, only a handful of larger dominant males mate with regularity, and they maintain their status by bullying their rivals. Bruce, unquestionably, is one of the dominant males along his stretch of river, and out of all of the times we have seen Wood Turtles mating there, Bruce was involved almost half the time. We have also seen him chasing other large males away from females, biting at the feet of young males as they flee, and on a couple occasions he has approached us with deliberation, as if he was investigating our footwear to make sure it is not a potential mate or rival.

As one of the dominant male Wood Turtles at this site in Northeastern Vermont, we have observed Bruce mating several times, including the morning after an early season snowfall in October, 2020.

In early May, Bruce emerges from a hibernacula he shares with five or six other turtles, spends much of the very early spring sunning himself on an eroding grassy streambank, and then begins his travels. Unlike females, which spend much of the summer away from the river, adult male Wood Turtles spend more of their time traveling up and down the stream, essentially patrolling back and forth in hopes of encountering females as they periodically return to the river. When we run into Bruce one day, it is not unusual to find him half a kilometer upstream the next time we see him, then back at the original location only a few days later. Although we normally capture any Wood Turtle we find between April and November so we can take measurements and verify their ID, we see Bruce so often that we usually recognize him as we approach, take coordinates, and then back off without troubling him any further except once at the start and end of every season.

During several habitat restoration work days, Bruce happened to be near the tree and shrub planting locations and was introduced to the field crew, most of whom had never seen a Wood Turtle before and developed a stronger appreciation for the work they do to restore riparian habitat as a result.

Bruce has also developed a reputation among some local conservation partners who are assisting with efforts to restore streambank habitat at his overwintering site. So far The Orianne Society, in partnership with the US Fish and Wildlife Service and a field crew from The Intervale Center, has organized three tree and shrub plantings on-site to stabilize eroding soils and improve foraging habitat. In every case, when I went out to find a Wood Turtle to show the restoration crew, out of the ~50 Wood Turtles we know from the site, it’s always Bruce who shows up for the educational show-and-tell, which is great because he never hides in his shell, so the people working to improve his habitat get to see a turtle with a very charismatic personality, which can have a more meaningful impact than just seeing a turtle shell with its head an legs concealed within. And while I am under no illusion that Bruce finds the same meaning in his interactions with us, he also does not seem overly perturbed and was once observed mating with another turtle less than half an hour after being handled and released. That being said, being captured and handled is stressful to any wild animal and handling wildlife should be done only when necessary, with state permits, and minimized to the greatest extent possible.

On a survey in 2019, a new volunteer shouted excitedly upon finding her first Wood Turtle, which turned out to be Bruce, who was farther away from the river that day than he has ever been documented.

At the end of the day, Bruce is just another Wood Turtle at that site, no more or less special than any of the others. On surveys, we don’t look for Bruce, we just conduct the surveys and if we do encounter him, he’s entered as Wood Turtle #VT-M-069, but I’d be lying if I said I’m not disappointed when he doesn’t turn up. As experts at avoiding detection, the odds are that Bruce has seen us far more times than we have seen him. Whether he recognizes us will remain a mystery.