The northern red-bellied cooter is a large basking turtle in the family Emydidae that occupies a variety of aquatic habitats in southeastern Massachusetts. Although the Massachusetts' population was originally listed in 1980 under the Endangered Species Act as a subspecies called the Plymouth redbelly turtle, the Service completed a 5-year review in 2007 that reexamined the taxonomic status. The review concluded with a recommendation that the Massachusetts' population remain on the endangered species list, but as a distinct population segment rather than as a subspecies. 

At the time of listing, northern red-bellied cooters in Massachusetts were known to occupy only 12 ponds, with an estimated population of approximately 200 individuals. In 1985, the Massachusetts Division of Fisheries and Wildlife, in partnership with the U.S. Fish and Wildlife Service, began a headstarting program that raises wild-born hatchlings in captivity for nine months to maximize growth before releasing them into the wild. Eggs and hatchlings are particularly vulnerable to predation, and the larger size of headstarted turtles is expected to reduce this vulnerability. This program has been successful at headstarting over 4,400 individuals and has contributed to increases in the number of northern red-bellied cooters in Massachusetts and the variety of ponds, rivers, and aquatic habitats in which they can be found. 

Some of the threats this species faces include habitat fragmentation, development of shoreline habitat, impacts to water quality, road mortality, human disturbance, and predation. Land development and land use change is expected to continue to occur within this species’ limited range due to proximity to urban areas and the coast. Adaptive conservation efforts that address known threats and respond to new challenges as they are identified will be important strategies on the road to recovery.