Down a gravel road, just on the Washington side of the Columbia River Gorge in Skamania County, is a 64-acre sanctuary for the western pond turtle.

Turtle Haven isn’t on any maps, and the few volunteers who trek out to the sanctuary are advised not to post about it.

One of the first rules of Turtle Haven is you don’t talk about the location of Turtle Haven.

But it’s here, in this undisclosed plot of ponds, freshwater springs and wetlands, that a population of native western pond turtles is growing.

Last month, the inaugural group of 16 baby turtles, who were captive-reared for their first year at the Oregon Zoo, were released at the site. Zoo staff arrived at Turtle Haven with Tupperware-style containers full of young turtles, which were released into the ponds by volunteers.

The turtles will live the rest of their lives — up to 50 years — at Turtle Haven preserve.

The western pond turtle is one of only two native freshwater turtles in Oregon and Washington. It’s designated endangered by the state of Washington, has “sensitive-critical” status in Oregon, and is a candidate species under the federal Endangered Species Act.

The turtles have suffered from loss of habit and from nonnative predators like bullfrogs, which swallow up tiny hatchling turtles.

“They’re not great swimmers that first year, they sort of float around like a bobber, and they’re really easy for bullfrogs to take,” said Stefanie Bergh, a wildlife biologist with the Washington Department of Fish & Wildlife.

Humans haven’t helped. Turtles are sometimes plucked from the wild and kept as pets. On the flip side, red-eared pond sliders — a popular pet store turtle — have been released by ex-owners into the wild, where they compete with native turtles for resources.

And then there are cars.

“We’re concerned if (Turtle Haven) were to be opened to the public, just the traffic alone, we know that already a female was run over by a vehicle just driving down this road,” said Sara Woods, stewardship coordinator for Friends of the Columbia Gorge Land Trust.

If you accidentally stumble across Turtle Haven, you’ll find signs along the roadway alerting you that, in fact, Google Maps is wrong and you have not found a shortcut to your hiking trail.

Those lucky enough to be invited to Turtle Haven will find beautiful sloping forests on what was formerly a private residence. When it came on the market in 2015, the Friends of the Columbia Gorge Land Trust quickly purchased the property.

The Friends began clearing the area of bullfrogs and bullfrog egg masses. Over the past three years, 3,274 bullfrogs and tadpoles were culled from Turtle Haven and on adjacent U.S. Forest Service property, Bergh said. A female bullfrog can lay up to 20,000 eggs in an egg mass, so it’s important to remove them.

Biologists knew the area was already home to a small population of western pond turtles. In the 1980s, Washington Fish & Wildlife surveyed the state and found only about 125 turtles. They were living in just two geographical areas — one of which was the property that would become Turtle Haven.

In the 1990s, Washington Fish & Wildlife created a “Head Start” program for baby western pond turtles. They put small radio transmitters on adult female turtles, tracked where they would lay their eggs and then dug them up. The hatchling turtles were collected and sent to the Oregon Zoo, where they were captive-reared for their first year. (Visitors can see the current crop of baby turtles at the zoo’s Turtle Lab.)

That first year is the most dangerous time for turtle hatchlings, when they are most likely to be swallowed whole by a predator. They weigh about 5 grams and are about the size of a thumb.

After a year of safe rearing, the turtles are still tiny but now weigh about 50 grams and are nearly the size of a palm. They leave with an implanted microchip, which will help biologists study how they fare and where they end up.

Under the Head Start program, Washington’s western pond turtle population has grown to an estimated 1,000 turtles and six populations — four of which are along the Columbia River Gorge.

“We’re doing better, but there’s still a lot of work we can do to grow the populations and make sure they are going to be able to survive into the future,” Bergh said.

-- Samantha Swindler; @editorswindler; sswindler@oregonian.com

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