A Year in the Life of a Wood Turtle

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Earlier this fall, I decided to swing by an old study site to see if I could sneak a peek at any Wood Turtles in their overwintering habitat. This was in late November, by which point you might expect Wood Turtles in Vermont to be hunkered down in their hibernacula. Instead, I spotted 15 Wood Turtles, most of which were active underwater, including two mating pairs. While that was later than I had ever seen Wood Turtles mating this far north, it wasn’t a huge surprise. 

Wood Turtles continue to mate underwater late into fall, even in late November.

Early spring and mid-to-late fall are when most mating occurs in this species. Throughout the year, Wood Turtles have a fairly predictable schedule, and many of the best management practices for the land that Wood Turtles use depend on that schedule. So, I thought it might be helpful to walk through a typical year in the life of a Wood Turtle.

Wood Turtles can be found from Virginia to as far north as Nova Scotia, and winters at opposite ends of that range are very different. As such, the dates I mention may vary, and I will base this article on my experiences in Vermont. The below figure approximates the dates of Wood Turtle activities across their range: 

Infographic depicting changes in Wood Turtle activity throughout a year from Roberts, H. P., M. T. Jones, and L. L. Willey. 2017. A Guide to Habitat Management for Wood Turtles. U.S. Fish and Wildlife Service Competitive State Wildlife Grants.

Winter

In Vermont, late November through early April generally marks a period of inactivity for Wood Turtles. During that time, they’ll hunker down underwater in valley streams, usually hidden under log jams, below beaver dams, in leafy debris, or inside undercut banks. They’re really just looking for a place that protects them from strong currents and hides them from predators. They usually won’t surface for air during that time and can get all the oxygen they need by absorbing it from the water. Sometimes they’ll move around, but it would be unusual for them to move more than a hundred feet or so. Some people have even seen them walking along the stream bottom through river ice. On very rare occasions, you might even see a Wood Turtle on land sunning itself mid-winter, possibly on top of snow.  

Tracking Wood Turtles using radio telemetry mid-winter with a USFWS biologist, most of the turtle had not moved from their last known location, but one had moved 50 feet or so downstream under river ice.

Spring

Spring is a busy time for Wood Turtles and can be divided up into several sub-seasons. In the early spring, right after the snow starts to melt or warm weather sets in, the Wood Turtles begin to stir. After a few sunny days with temps at least in the high 40s, some Wood Turtles will start sunning themselves along the streambanks. Underwater, breeding begins in earnest at about the same time. In Vermont, this typically starts around mid-April, but farther south that could be a month or so sooner. So long as there is a risk of hard frost, the turtles will return to the streams most nights, but once things warm up a little more, they start to spread out. 

In the early spring, Wood Turtles won't venture far from their valley streams and will tuck themselves into vegetation along the stream banks to bask.

By mid-spring, the Wood Turtles are foraging and many start spending nights on land, venturing farther from water. During this time, they take advantage of everything spring has to offer, and forage on an abundance of slimy invertebrates, such as snails, and the shoots of budding vegetation. For the most part, the turtles will still remain in their floodplains. 

In the late spring, females start looking for a place to lay their eggs. Nesting usually occurs on prominent sand or gravel bars on the banks of the river. If there isn’t a great nesting beach nearby, they’ll either head upland to nest in farm fields or along roadsides, or they might travel miles up or downstream to the nearest sand or gravel bar they can find. In Vermont, we documented a female make the same journey about three miles downstream two years in a row to nest. Nesting starts wrapping up in mid-June, with some stragglers still nesting in early July. After that, Wood Turtles become very hard to find. 

Late May through early July, females seek open sandy habitat to nest, ideally on prominent sand or gravel bars above their rivers.

Summer

Up until this point in the year, Wood Turtles stay in or very close to streams. That is why we target our Wood Turtle surveys for the spring season. We can walk the streambanks at places with the right habitat and reasonably expect to find them. By summer, however, the turtles could be hundreds or even thousands of feet away from water using a variety of habitats. Females spend more time on land and tend to move farther from streams, and they might spend weeks or even months away from rivers. Males stick closer to the streams in hopes of encountering females on their occasional return trips to water, but the males are also mostly terrestrial at this point. A needle in a haystack, or hay field to put it more precisely. I rarely look for Wood Turtles in the summer because my success rate is very low.  

Mid-summer, Wood Turtles can be found almost anywhere within a thousand feet or so of their streams and may spend weeks on end on land.

Fall

Like spring, fall has a few sub-seasons as far as Wood Turtles are concerned. In September in Vermont, they begin their return trips to the valley streams where they will overwinter. By early October, they should be spending most of their nights in the water again. Then, by mid-to-late October, they are pretty much done venturing onto land except on unusually warm days. Like spring, there is a big uptick in breeding activity in the fall, mostly because those are the two times of year when the Wood Turtles are active and likely to encounter each other. Breeding might continue through November, but by December, they are mostly inactive, tucked into their preferred aquatic shelter.  

A Year in the Lives of Two Wood Turtles

To use some real turtle data as examples, the below maps show the land use of two females who behaved very differently from one another. One was on the go in the woods all summer and traveled several miles total, ranging over half a mile from her stream at one point. The other spent almost the entire year on a single property in a wooded wetland and hay field, but traveled 1.2 miles downstream to lay her eggs. What they have in common, however, is that they started basking in April, stopped going back to the stream every night in May, nested in early June, spent the summer on land, then returned to their stream in September, and were mostly aquatic again by October. 

This female Wood Turtle spent most of the year on a single property, but traveled 1.2 miles downstream to nest.
This female Wood Turtle traveled several miles, mostly on land, through the summer and ended up over half a mile from her stream.

Connecting Wood Turtle Seasonality to Land Management

This pattern of land use is helpful when it comes to planning land management. For example, if a field used by Wood Turtles is mowed only to keep the land open, mowing can be timed for early or late in the season when the turtles are unlikely to be on land. In Vermont, any time after October 15 is a pretty safe bet. If a field needs to be hayed during the growing season and there is a nest site nearby, delaying the cut until after nesting is a huge help, especially close to the nest site. In the summer, if a field needs to be cut, there will be risks, but raising mower blades to 6 inches or using a sickle-bar mower instead of disc or rotary mowers can lower that risk. There are lots of case-by-case specifics when it comes to Wood Turtle habitat management. Understanding how Wood Turtles use their habitat and how that changes throughout the year is fundamental to finding the right balance between turtle conservation and the many different ways humans use the land.   

Learn more about Wood Turtles, one of our priority species.