Wood turtles declining in Minnesota
New federal grant aids effort to save species from extirpation.
The news for wood turtles in Minnesota is not good.
According to the Minnesota Department of Natural Resources’ Wood Turtle Habitat Conservation Plan, finalized in 2020, declining population trends for the reptile are cause for concern and they are in danger of disappearing from the region entirely.
“Some populations are dominated by older adult turtles with little evidence of juvenile recruitment,’’ the plan notes. “Overall, populations are generally small, isolated and at risk for extirpation.”
And it’s not just a Minnesota problem. The International Union for the Conservation of Nature has classified wood turtles as endangered across their range — the Northeastern U.S. and eastern Canada — since 2010.
Wood turtles were once common in most of eastern Minnesota, from St. Louis County in the north to the Iowa border. They thrived in areas with sandy shorelines along rivers with plenty of forest nearby.
But wood turtles spend more time on land than most other Minnesota turtles, and that makes them more vulnerable to humans — namely vehicles on roads and habitat loss from waterfront development. Adult female wood turtles spend a good portion of their summer and fall on land eating berries, worms, mushrooms and insects, sometimes miles from their favorite river.
Not only are there fewer undeveloped sandy shoreline places to lay their eggs, but nests that are made are more often being destroyed by predators like fox, raccoons, skunks and coyotes. In one study by researchers at UMD’s Natural Resources Research Institute virtually every wood turtle nest egg was dug up and eaten.
And not only are there fewer wood turtles making it to adulthood but more adult turtles are dying, and researchers aren’t sure why. Surveys conducted from 2016 to 2018 found a “substantial decrease in the number of individuals at eight monitoring sites coinciding with a large number of dead turtles of unknown cause found at the same sites.”
The estimated number of wood turtles at those eight sights in eastern Minnesota plummeted from 247 in 2016 to just 88 by 2018.
The federal grant, with state matching money from the Minnesota Nongame Wildlife Fund, is helping wildlife experts determine which actions work best to help wood turtles recover — things like developing flood-safe nesting areas, protecting nests from predators, installing barriers to keep turtles off roads and enhancing foraging habitat.