Researchers trying to restore woodrat’s population


Sun-Gazette Correspondent

Efforts are being made to help preserve – and increase – the populations of Allegheny woodrats that now exist in Pennsylvania.

Management plans and studies are helping with these efforts.

“A lot has been researched, trying to map out woodrats and get an idea where they are at,” said Cal Butchkoski, wildlife biologist with the state Game Commission’s diversity section of non-game mammals. “Before, it has been a hands-off type thing and now we are trying to do management – like increase food around denning sites.”

Old rock quarries also are being used to create habitat for the woodrat.

Teams at Delaware Valley College in Doylestown and Indiana University of Pennsylvania (IUP) are working on studying the Allegheny woodrat.

IUP is monitoring the reaction to management strategies on state gamelands in southcentral counties “to see if it can make a difference,” Butchkoski said.

Dr. Jeff Larkin, professor of wildlife ecology in IUP’s Department of Biology, said the college has been studying woodrats in Pennsylvania since 2007.

He and his partner, Dr. Joseph Duchamp, in the field of wildlife population and community ecology, mammalogy and biostatistics in the biology department, worked together in the study for three years, ending in 2009.

Larkin said they looked at the demographics of the survival reproduction and population size in relation to the Allegheny woodrat’s habitat and characteristics.

Professors and students actually went out to sites to trap woodrats. They would mark a certain number at each site and be back again later to measure the habitat components.

“That would be any number of acorn-producing trees or the amount of rock habitat available … all sorts of characteristics related to the woodrat ecology,” Larkin said.

The study helped identify the habitat features that are the most important to woodrat demographics.

After the 2009 study ended, Larkin said it was boiled down to make habitat management recommendations for the animal.

Last year, IUP’s biology department received funding through a grant to start a habitat project for the Allegheny woodrat in Pennsylvania.

“We visited, with students, 12 woodrat sites and monitored density there at the sites,” Larkin said. “We then selected six sites and, this winter, the Game Commission implemented habitat recommendation for those sites.”

The six sites that were not treated with the habitat management plans will be compared to the six that are now being treated.

“Hopefully (we’ll) see the response,” Larkin said.

They are getting ready to send out three crews of two people to as many woodrat habitats they can get to, he added. More studying and monitoring will commence.

“(There are) 90 sites this summer across the state and some in your neck of the woods,” Larkin said.

“We set traps at night, catch woodrats and take small samples,” he said.

From those small tissue samples, they can study the genetics of the woodrats living in that particular spot.

Larkin said they hope to develop a genetic atlas of the Allegheny woodrat from the sampling.

With such a multitude of data, Larkin said, they hope to develop a good, sturdy plan for the woodrat.

“Once we have all those things figured, we have a reasonably solid strategic (plan) of woodrat conservation for Pennsylvania,” he said.

Butchkoski said Delaware Valley College has taken over a captive breeding colony from Purdue University and is looking into genetic diversity.

“Once we have an inventory of genetic diversity and what it is lacking, we can come up with a soft release to introduce more of the diverse animals into a population,” Butchkoski said.

The Game Commission has several adaptive management strategies in place. One involves cutting birch and maple trees to help make daylight areas for more food to grow for the woodrat.

“We may be daylighting some oak and hickory in the sub-canopy and daylight the forest floor,” Butchkoski said. “A lot of habitat of the woodrat is in areas that are dominated by red maple and black birch. We knock it down and reduce competition.”

Planting strategies also are in place in which plants such as blackberry and green briar are seeded.

Butchkoski hopes they soon will be able to plant American chestnut again, once a rich food source for the woodrat.

“I think woodrat areas would be a good first step back on the mountains, where chestnuts should be,” Butchkoski said.