Great Swamp Wildlife Management Area, Rhode Island

Wildlife Follow Corridors Between Habitats

Powerlines transmit much-needed electricity, and they can also serve a completely different function: provide movement corridors for wildlife. That’s what’s happening on a right-of-way that bisects 3,745-acre Great Swamp Wildlife Management Area in southern Rhode Island. National Grid is managing a crucial half-mile of their 100-foot-wide right-of-way as a swath of thick, low-growing shrubs that offers food and hiding cover to a range of creatures, including many that are considered Species of Greatest Conservation Need in Rhode Island.

Fresh young forest habitat at Great Swamp WMA showing autumn colors./C. Fergus

Most of Great Swamp WMA is cloaked with 60- to 100-year-old forest. Those wooded areas are valuable habitat for some animals but less useful to others. The Rhode Island Division of Fish and Wildlife recognized that more of the WMA should be younger, denser woodland to help the creatures – rabbits, woodcock, towhees, indigo buntings, blue-winged warblers, and box turtles, to name a few – that need thick habitat. The National Grid powerline borders a part of the WMA where biologist Brian Tefft has overseen a series of timber harvests to make much-needed young forest. Wildlife can now use the right-of-way’s dense vegetation to move between the patches of new habitat created by the cuts.

Timber harvests in 1995, 2007, and 2012 jump-started around 60 acres of regrowing forest of differing ages and tree and shrub species and stem densities. Another 40 acres in nearby forest blocks are scheduled for harvesting in the near future.

Where possible, tree-cutters left American holly, a low, shrubby tree that flourishes when taller trees that cast shade on it are removed. Wood thrushes and other songbirds home in on the hollies in late summer and early fall to feed on the trees’ fruits, putting on body fat before starting their migration southward.

Studying the American Woodcock

Another bird clearly helped by the timber harvests is the American woodcock. Male woodcock sing and conduct aerial display flights above recently cut areas and in nearby grass fields and forest openings that conservationists keep open through mowing and brush-hogging.

URI researcher Roger Masse handles woodcock captured in mist net at Great Swamp WMA./Gerald Krausse

After mating, female woodcock home in on the harvest stands to nest and rear young among the densely regrowing small trees. The thick cover lets hens and their broods avoid ground and avian predators.

In 2011 and 2012, researchers from the University of Rhode joined Tefft in capturing 92 male woodcock on Great Swamp WMA during the spring breeding season. The biologists fitted the woodcock with radio transmitters, then monitored the birds’ daytime locations through the summer to learn what kinds of habitats they used.

During daytime, the woodcock consistently sought out areas of forest with thick ground-hugging vegetation and damp soil, where high numbers of earthworms – their primary prey – could be found. Some birds flew as far as a mile to feed in the floodplain forests of nearby rivers. Those daytime habitats had a dense understory of shade-tolerant shrubs, such as viburnums, sweet pepperbush, maleberry, and greenbrier, as well as damp soil that supported an abundance of worms. The study helps inform management decisions on where to site timber harvests if creating woodcock habitat is a primary goal.

A New Home for New England Cottontails

Great Swamp WMA is part of a Focus Area where conservationists are making habitat for the New England cottontail. Also known as a “brush rabbit,” the New England cottontail needs the thick, dense cover provided by young forest. As that type of habitat has dwindled across southern New England over the last 50 years, the population of the New England cottontail has fallen.

New England cottontails may be released in habitat created by conservationists on Great Swamp WMA.

At one time, those native rabbits were common on Great Swamp WMA. But now the area is inhabited mainly by eastern cottontails, a non-native rabbit imported from the Midwest during the last century. The eastern cottontail can use smaller, thinner patches of habitat than the New England cottontail.

Over a span of ten years, biologists found no evidence of New England cottontails at Great Swamp. But that has changed recently. In March 2016, biologists live-trapped 20 New England cottontails on Patience Island in Narragansett Bay, from a breeding colony that conservationists created there in 2012, and relocated them to good habitat created on Great Swamp WMA. Several of the rabbits survived through the summer and fall, and biologists expect that one or more of the females may have produced young. Additional captive-raised zoo rabbits were added to the patch in late fall of 2016, and more will be brought in from Patience Island in spring 2017. Conservationists hope that the Great Swamp population will continue to grow and expand, establishing itself as a self-sustaining colony.

Partners

Rhode Island Division of Fish and Wildlife, University of Rhode Island, National Grid, Natural Resources Conservation Service, U.S. Fish and Wildlife Service, U.S. Geological Survey, National Fish and Wildlife Foundation, Northeast Association of Fish and Wildlife Agencies, Wildlife Management Institute.

How to Visit

Young forest management sites on Great Swamp WMA are in gated-off areas that can be reached on foot. For more information, contact Brian Tefft, Wildlife Biologist, Rhode Island Division of Fish and Wildlife, 277 Great Neck Rd., West Kingston RI 02892, 401-789-0281, email brian.tefft@dem.ri.gov