Pennsylvania joins states pushing for recovery of Allegheny carpenter rat populations

A species of rat native to the Appalachian Mountains will be the focus of a new program that will help populations recover in several states, including Pennsylvania, where the animal’s survival has faltered in recent decades.

The Allegheny woodrat, one of several types of pack rats, has a more mouse-like appearance with a bushy tail and a larger head than most rats. Historically, the species had a range extending from southwestern Connecticut to northern Alabama and west to Indiana. Forest habitats throughout their range have become fragmented and have lost food sources due to invasive species, as well as competition from other wildlife. The decline in their numbers has also been attributed to a deadly parasite spread by raccoons.

Pennsylvania’s Allegheny woodrat population has declined by about 70% over the past 40 years, according to the Pennsylvania Game Commission.

To rebuild their population in the wild, the game commission is partnering with the Maryland Zoo and the Wildlife Futures Program at the University of Pennsylvania School of Veterinary Medicine. The organizations have begun a captive breeding program at the Maryland Zoo, where a colony will be established and adapted to the wild before being released on their own.

The first of the Allegheny woodrats on the show is a female that was found in Mifflin County. Once in captivity, her keepers learned that she was pregnant and she gave birth to three cubs. Woodpecker rats from Virginia and Indiana will be brought to the Maryland Zoo to help raise future generations.

“Woodrat populations have declined so much that they have become isolated from each other,” said Kate Amspacher Otterbein, a mammal recovery specialist with the game commission. “That leads to low genetic diversity and eventually inbreeding, which is yet another factor in population decline.”

Woodpecker rats forage for food and build large food reserves to survive the winters. They are nicknamed pack rats because they collect all kinds of items, from shotgun shells to bottle caps. As adults, they weigh less than a pound and measure about 17 inches with their 8-inch tails.

To make sure the woodrats in the program are prepared to return to the wild, Maryland Zoo staff are heavily monitoring them using a nest camera. This is to prevent them from forming human bonds that could compromise their survival in the wild.

“We previously had Allegheny woodrats and were pretty successful at breeding them, so I’m optimistic about having a lot of babies to release into the wild,” said Erin Cantwell Grimm, curator of mammals at the Maryland Zoo.

The species is considered endangered in Indiana, Ohio, Maryland, New Jersey and New York. It is a species of conservation concern in Pennsylvania, Virginia, Tennessee, Kentucky, North Carolina, and West Virginia. The goal of the program is to increase populations throughout the area and prevent the species from being added to the federal endangered list.