Doyle is assisting with the captive breeding program, which is being administered through a special work group dedicated to the creatures. By comparing DNA samples collected from the baby woodrats, and samples collected in the wild, Doyle will help play matchmaker, by identifying the woodrat populations most in need of the pups’ unique genetic background.

But at the beginning of their lives at the Maryland Zoo, these potential species-savers were just like any other kids. As soon as the lights went off each night and the cameras switched to infrared, the nocturnal “rat chaos” would begin, Grimm said. The siblings often sparred with one another, rising to stand on their back feet and box with their paws. That is, until Mom separated them.

The woodrats grew in a multilayer cage with PVC piping for tunnels. And that cage was locked behind latched, lion-proof metal doors, since it sits inside a room previously used to treat the zoo’s other, much larger, inhabitants. Now, a whiteboard hangs out front, with a drawing of a rat and the words “Rat Room.”

After Mom and the kids spent several weeks together, zoo staff separated them. Now, each woodrat has its own enclosure. Zoo staff are keeping their distance, trying to ensure that the young woodrats don’t grow too accustomed to humans, or hearing human voices. Soon, the woodrats will go to the wild, where they will spend their first two weeks in an enclosed area with natural food items. Then, the gates will open, and eventually the enclosure will be removed, leaving them on their own.

The zoo employees weren’t sure how Mom would react to losing her young. But mostly, she just seemed to take some much-needed R&R, sleeping in her nest assembled partially from her favorite nesting material — toilet paper — and munching on the chinchilla chow, seeds, nuts and fresh produce that arrive through a chute.

Along the way, the zoo is picking up meaningful tidbits about woodrat behavior that will help other zoos that are discussing how to replicate the program, Grimm said. For the Maryland Zoo, the breeding program isn’t atypical, said spokesman Mike Evitts. The zoo participates in similar programs for the African penguin and the Panamanian golden frog. Such programs are a bit more rare for mammals that are difficult to breed, Grimm said, though the zoo had a brief breeding program for woodrats decades ago.

Perhaps the program’s biggest challenges lie ahead: ensuring that the baby woodrats survive in the wild, and successfully mating Woodrat 9891 in captivity, said Kate Otterbein, a mammal recovery specialist at the Pennsylvania Game Commission, who trapped Woodrat 9891 in central Pennsylvania’s Mifflin County and drove her to Baltimore.

“It’s not simple as just putting them together, because they’re not social and they are territorial, and they get aggressive when another woodrat is in their territory,” Otterbein said.

Staff members will need to carefully monitor the courting, to ensure it doesn’t sour to the point that one of the woodrats becomes violent, Otterbein said.

The Allegheny woodrat is listed as endangered in Maryland and several other states, and is “near threatened” on a global scale, as measured by the International Union for Conservation of Nature’s Red List.

...continued

©2024 The Baltimore Sun. Visit at baltimoresun.com. Distributed by Tribune Content Agency, LLC.