Captive Breeding Part of the Plan
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.
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.
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.
By examining fecal pellets, graduate student Wendy Finn in the WGEL is analyzing the diet of rabbits on Patience Island, as well as the nutritional qualities of vegetation growing there. The WGEL is also conducting landscape genomic analyses of both New England cottontails and eastern cottontails to identify habitat variables that either facilitate or prevent the movement of genetic material within each species.
Captive breeding is but one facet of a regionwide effort to restore a once-common rabbit whose population has plummeted over the last 50 years. Throughout the states that still have New England cottontails, conservationists are creating and renewing the habitat that the species needs: brushy land, clearcut woods regrowing into young forest, thickets, and old fields dense with shrubs. They are concentrating their efforts in designated focus areas, where habitat restoration is likely to help cottontails the most.
Learn more about efforts at Roger Williams Park Zoo to help New England cottontails. For more information, contact Janet Mariani, director of marketing and public relations at the zoo, 401-785-3510, extension 378, firstname.lastname@example.org, or Lou Perotti, director of conservation programs, 401-785-3510, extension 335, email@example.com.