By JESSICA WELSHANS
Mention the word "rat" and what comes to mind are thoughts of vermin scurrying around dumpsters and sewers.
But there is an animal that happens to be a rat that is native to the forested areas of Pennsylvania and prefers that wilderness over cityscapes.
The Allegheny woodrat lives in the Appalachian Mountains from New York to Georgia and as far west as Indiana. It has a long, fur-covered tail, unlike its counterpart, the Norway rat, which has a scaly tail that is free of fur.
The hair on the tail of the woodrat is dark on top and white underneath. The animals grow to 14 to 17 inches long.
The forest dwellers have long whiskers that sweep the face and, along with the furry tail, are a good, tell-tale way to identify the woodrat, experts say.
"It's kind of like a squirrel (but) instead, it likes rocks and large tracts of forest, well away from human activity and in remote areas," said Cal Butchkoski, a wildlife biologist with the diversity section of non-game mammals within the state Game Commission.
According to the Pennsylvania National Heritage Program, the Allegheny woodrats' population in Pennsylvania were healthy during the 1940s and 1950s.
Studies conducted in the late 1970s for bats found an absence of woodrats inside caves. A noted decline began, and the animal now is listed as a threatened species in Pennsylvania.
A threatened species means they are vulnerable to endangerment.
Today, their range is very restricted.
"They are really neat animals and most (people) do not know we have them," Butchkoski said.
A population recently was found in the Pine Creek Valley.
"We have them in Pine Creek again and there is some management going on there through environmental consulting," Butchkoski said.
He said a slow decline has continued over the years and, according to studies, the woodrat is losing range. They do not seem to be expanding in the state.
Home sweet rock
The woodrat's habitat preference are rocky outcrops and, sometimes, limestone caves.
When research crews look for the animals, Butchkoski said, what they look for may not be the normal identifier they use to find other species.
"We look for rock crevices and we look for toilet areas - nice, neat toilet areas that are usually under a rock overhang," he said.
Finding these toilet areas with excrement, which is shaped similar to pellets from mice, is important when it comes to making a decision about whether woodrats live there.
"You have to see it before you can say it's a woodrat," he said of the excrement. Piles of waste can be 6 inches to a foot in diameter.
Mostly, Butchkoski said, woodrats will pick the southside-facing slope for toilet areas and denning. They like the sun but can be found on the north side, too.
"Southwestern isn't all that bad, either. River gorges ... they meander around in those, too," Butchkoski said.
Porcupines also call rocky outcrops home. They like the rocks and hillsides as denning sites.
The perfect site for a woodrat would include these features, Butchkoski said, as well as a location in a very remote area.
Finding the food
"Historically their range followed that of the American chestnut," Butchkoski said. It once was considered a major food source for the woodrat.
In the 1900s, the American chestnut was virtually wiped out of existence by a blight.
Now, woodrats eat grasses, wildflowers, seeds, fruits, berries and acorns.
They forage at night and can travel several hundred yards around their den site to find sustenance.
The animals cache their food, usually in early winter.
"They are cutting grains and collecting wildflowers and sometimes they will put them under the protection of a overhang to allow them to dry," Butchkoski said.
While foraging, the woodrats can become food themselves for bobcats, gray foxes and black snakes.
'Oh, look ... shiny'
The term "packrat" can be used to describe a behavior of the Allegheny woodrat
"Packrat of the east" is how Butchkoski describes them.
"They will pick up just about anything," he said
Those "anythings" are used to decorate their nests.
"I saw one nest off the West Branch of the Susquehanna (River) that had a bunch of paper, aluminum foil and turkey vulture feathers in it ... and a bobcat skull in there," Butchkoski said.
He thinks the woodrats probably used the fur to line its nest and carried the skull in there to do so.
"We found a credit card in one. I think he (a hunter, likely) lost his whole billfold. It was the credit card, business cards ... I couldn't find the rest of the billfold," Butchkoski said.
"The woodrats probably stashed the cash in (there), way back," Butchkoski joked.
Why the disappearing act
Aside from losing the American chestnut as a main food source, forest fragmentation is a big problem for the woodrat.
Forest fragmentation is when an area is cut or changed from a running tract of forest into smaller spaces, breaking up the tract.
"There is no way for animals to move and preoccupy the other spaces," when fragmentation happens, Butchkoski said.
"As the forest gets broken up, more animals start using these rocks (where woodrats already may be located). Moles, raccoons and weasels can carry diseases and predate on woodrats," he said.
The raccoons that may share the area can carry roundworm, which can kill woodrats.
Butchkoski said the Appalachian Mountains are the spine of the woodrat's range. As it becomes broken up, it causes the flow of genetics in the woodrat to be broken up, too.
"Up in your area, the East Branch of the Susquehanna is broken up through the Allegheny Ridge. That is probably a connection for the West Branch of the Susquehanna population," Butchkoski said.
Weakened numbers also can come from inbreeding.
"There is an inbreeding problem with isolated populations," Butchkoski said.
In addition, they are prone to high mortality rates.
Woodrats have about four to five pups per year in captivity, but Butchkoski said no one really knows the actual number of pups born in the wild because most do not make it above ground.
"So the question is, are they having three litters a year, two to three times a year," Butchkoski said.
And, he added, they question if the pups are making it to the next year.
The maximum life expectancy of a woodrat is around four years.
Is that what I think it is?
People who think they might have a woodrat in their backyards or near their houses probably are mistaken, Butchkoski said.
"It's probably a Norway rat," he said.
Woodrats have a specialized habitat.
You're more likely to see a woodrat at a cabin in the woods, especially near rock outcroppings.
"They will take advantage of your hunting cabin and move in," he said.
In a book Butchkoski once read, the author wrote about growing up around woodrats in the hills of West Virginia.
He remembers one passage in which the woodrats were getting into the author's house and he saw one run off with one of his mom's pot lids.
"I think we would be missing something from the mountains of Pennsylvania if we lost the woodrat," Butchkoski said.