Saving the woodrats: Zoo raises endangered species for wild release

Woodrats have other environmental factors working against them. Raccoons, for example, pushed by human development, have foraged deeper into the woods, where they are more likely to encounter Allegheny woodrats. Raccoons can carry a parasite called racoon roundworm, which lies dormant inside them, but is typically lethal when passed to a woodrat. The woodrats’ food sources have also taken a hit, such as chestnut trees destroyed by chestnut blight and acorn-producing oak trees imperiled by the spongy moth.

The Maryland Department of Natural Resources is beginning a statewide reassessment survey of its remaining woodrat populations, said Megan Zagorski, the agency’s western region ecologist. Historically, the creatures could be found in the state’s westernmost four counties and Montgomery County. Over time, the population generally appears to be contracting westward, as sites that formerly hosted woodrats are lost.

Zagorski hopes the holistic survey will provide meaningful answers to explain the decline, but the state’s existing survey work has provided clues, including trail cameras that pick up families of raccoons passing by.

“One of the sites … is one mountain and the next mountain, and in between those two mountains, put a highway,” Zagorski said. “So it’s much more difficult for woodrats to safely cross and mix across that ridge line.”

In addition to the captive breeding program, state officials are trying other methods to keep the critters alive. In Pennsylvania, that comes in the form of taxing work: At key times of the year, state employees and volunteers haul 25-pound bags of chestnuts up into the mountains to drop them in crevices only hungry woodrats could reach, Otterbein said. The state game commission also has worked to rebuild rock areas to connect woodrat habitats, she said.

It’s not just about the woodrats. Their habitats also are used by rattlesnakes, birds of prey, black bears and other small mammals, such as rock moles, Otterbein said.

“I like to think of it as this complex puzzle of species that fit into this community, and the idea of losing some of those pieces of the puzzle is just not something that we want to face,” Otterbein said.

The woodrat also deserves study — and saving — on its own merits, the scientists say. There’s a lot of interest among scientists in working with what they call “charismatic megafauna,” Doyle said. Think polar bears, golden eagles, dolphins.

“The Allegheny woodrat is — perhaps some would argue — less charismatic. It’s certainly not mega,” Doyle said. “But it’s no less important ecologically than these top predators that many people are interested in studying.”