By Molly Murray
One of the region’s iconic and once-rare animals, the Delmarva fox squirrel, is being considered for delisting as a federal endangered species.
That’s because the population has grown and expanded in its native range, factors that federal officials say make it able to withstand future threats.
Fox squirrels were extinct in the state until an experimental reintroduction program in 1984. The recovery has not been extensive in Delaware, but state officials aren’t opposing the federal delisting proposal.
Habitat loss and hunting led to the population decline. The population fell to 10 percent of its historic range, confined mostly to remote areas of Maryland’s Eastern Shore. The animal was listed as an endangered species in 1967.
“They are still extremely rare in Delaware,” said Holly Niederriter, the state non-game and endangered species coordinator.
Regionally, the fox squirrel’s recovery has been impressive, aided by the government protections, changes in area forest use and the lack of hunting pressure.
The regional population of fox squirrels has expanded from 10 percent of its historic range in 1967 to 28 percent, said Cherry Keller, a biologist with the U.S. Fish & Wildlife Service’s Chesapeake Bay Field Office.
In addition, 11 of the 16 attempts at moving squirrels into new areas have been successful, Keller said.
“That’s actually a pretty good rate, she said.
Delaware now has just two known populations: one introduced in and around Prime Hook National Wildlife Refuge near Milton, and a second that turned up at Nanticoke Wildlife Area west of Seaford.
Most biologists believe the Seaford population expanded from nearby Maryland. A second population introduced at Assawoman Wildlife Area near Bethany Beach is believed to have died off.
Still, Niederriter said, there is a lot of suitable habitat available in Delaware and state officials view the delisting as an opportunity to expand the population through additional introductions, similar to what was done with wild turkeys over two decades beginning in the early 1980s.
Turkeys also were extinct in Delaware, but a reintroduction program grew the turkey population to the point that state officials opened up a hunting season for the birds.
Under a proposed plan, the state would double the number of locations where fox squirrels are found in the state over five years using reintroductions from Maryland, encouraging preservation of forests with trees that are 40 years old or older, and promoting habitat connectivity – a feature that could allow the population to move and expand on its own.
Nothing has stopped state officials from a reintroduction program for fox squirrels, but there was opposition.
During the peak of the coastal development boom, there was significant controversy among coastal land owners near the Prime Hook Refuge release site. They argued that the release was an experiment and not subject to the same stringent requirements of the Endangered Species Act. Federal officials disagreed.
“At one point, it became a real hot topic,” said Edward Launay, a consultant with Environmental Resources Inc. When federal officials started to enforce the Endangered Species Act because of the proximity to the introduced population “it came as kind of a surprise to everybody.”
Launay worked with some of the impacted landowners in the dispute with federal officials.
“I’m not sure they handled the initial concerns well,” he said.
But with delisting, many of the land use obstacles would disappear.
“Once they are off the federal list, we will have more flexibility,” Niederriter said.
Fox squirrels are larger than the gray squirrels most Delawareans see in urban, suburban and rural areas. Historically, they were found only on the Delmarva Peninsula, a small corner of southeastern Pennsylvania and perhaps – though no one is certain – in southern New Jersey.
Niederriter said it may not be possible to re-establish a population in northern Delaware because of significant habitat loss and fragmentation. But there is suitable habitat in parts of Kent County and throughout Sussex County.
In Sussex there are existing populations in the east and west, but no animals in central Sussex despite suitable habitat at places like Redden State Forest.
Once populations were relocated in Maryland, they began to expand on their own, she said.
The ideal habitat for fox squirrels is a mature forest of mixed pines and hardwoods, giving the squirrels lots of food choices, said Keller, the federal biologist.
By mature, she means a forest that is 40 years old or older and trees that are 12 inches in diameter.
Older forests are favored by squirrels because older trees often have cavities, which give the squirrels a natural place for a den site. They will also form dens with leaf nests. And the big trees give them a wide tree canopy, she said. That means there is more food in the forest.
In the past, when a large pulpwood industry thrived on the peninsula, trees were harvested at or before they reached the 40-year mark, Keller said.
But that industry has moved elsewhere, and much of the old timber tracts are now owned and managed by state agencies in Delaware and Maryland. Forests managed for sawmill timber are allowed to mature longer and trees are often harvested selectively.
“It’s not that narrow a niche” of habitat, she said.
As for seeing one of the animals, that’s a chancy bet. Even in places where the population is very healthy, it can be hard to spot one.
In Delaware, state and federal officials use wildlife cameras to monitor how the populations are doing and federal officials ask people to report fox squirrel sightings.
So far, the animals haven’t expanded into Virginia’s Eastern Shore but there is a Maryland population nearby, Keller said.
Federal officials will likely prepare a proposed delisting rule sometime this summer and ask for public comments. A final decision on delisting would follow.
If the animals are delisted, it would be the second animal found in the Delmarva region to come off the list. Bald eagles, also listed in 1967, were delisted in 2007.
“We’ve got great comebacks,” Keller said. “There’s a lot of good things happening. It’s not all gloom and doom in the environment.”