Restoring a Rare Rabbit

Posted by Wayne G. Barber

The New England cottontail lives in parts of New England and New York. Over the last 50 years the range of this once-common rabbit has shrunk and its population has dwindled so that today it needs our help to survive.
A critical threat is the loss of habitat – places where rabbits can find food, rear young, and escape predators. Development has taken much land once inhabited by cottontails and other wildlife. And thousands of acres that used to be young forest (ideal cottontail habitat) have grown up into older woods, where rabbits don't generally live.
Today the New England cottontail is restricted to southern Maine, southern New Hampshire, and parts of Massachusetts, Connecticut, Rhode Island, and New York east of the Hudson River - less than a fifth of its historic range.
Since 2010, captive breeding specialists at Roger Williams Park Zoo in Providence, R.I., have been working to perfect housing, feeding, and breeding techniques so that New England cottontails can be bred in captivity.

This New England cottontail was produced by the captive breeding program at Roger Williams Park Zoo, Providence, RI.

Conservationists have begun returning captive-bred rabbits to the wild to boost the numbers and genetic diversity of existing populations, and to start populations in places where good habitat exists but rabbits aren't present.
In 2015, the Queens Zoo, in New York, also joined the captive breeding effort and by year's end had successfully bred and raised 11 cottontails that were later set free in natural habitat.
As of October 2015, conservationists had released 118 captive-bred New England cottontails, 71 of them in Rhode Island and 47 in New Hampshire. One important release site is Patience Island, a brushy, 210-acre uninhabited island in Rhode Island’s Narragansett Bay. As this island population grows and thrives, it will become a key source for restocking other areas throughout the species' range.
Conservationists have also built four "hardening pens," enclosures where young captive-raised rabbits learn to hide in cover and feed on natural vegetation before being released into the wild in other areas. Pens are located at Ninigret National Wildlife Refuge in Rhode Island and Great Bay National Wildlife Refuge in New Hampshire.

Captive-bred rabbits are being released into the wild to establish new populations.

A Captive Breeding Working Group, made up of biologists from all six states with populations of New England cottontails, provides direction and advice in developing the captive breeding program. So far, breeding stock has come from rabbits live-trapped from healthy populations in Connecticut, New Hampshire, and Maine.
To help guide breeding pairings, conservation geneticists with the University of Rhode Island's Wildlife Genetics and Ecology Laboratory (WGEL), directed by Dr. T.J. McGreevy, are studying adaptive genetic variation in the cottontails that have been brought in as breeders. This information will also help maintain the adaptive potential of the New England cottontail population on Patience Island. The WGEL works closely with Brian Tefft, a wildlife biologist with the Rhode Island Division of Fish and Wildlife, to monitor the population size and genetic diversity of rabbits on the island, and to monitor the success of translocation efforts when rabbits are moved from Patience Island to habitat on the mainland.