Cotton mice take their name from the observed habit of using raw cotton in building nests. These little rodents have dark brown bodies and white feet and bellies. Their tails are short and sparsely haired.
Cotton mice occur in the Southeastern United States in an area roughly bordered by southeastern Virginia, Florida, Texas, and Kentucky. They inhabit a variety of habitats, including hardwood forests, swamps, the margins of cleared fields, edges of salt savanna and dunes, scrub, and rocky bluffs and ledges. They probably prefer terrain that is regularly inundated.
Cotton mice are solitary and nocturnal animals. They like to forage during dark hours. They are good climbers and swimmers. Cotton mice are territotial and males have larger territories than females. These mice use underground refuges such as stump holes, tree cavities, root boles, and burrows where they can avoid predators and wild fires. Such underground refuges also provide lower temperature and humidity during the summer season. Young are born in nests which are located in logs, moss, under loose bark or under brush. These animals prefer elevated nest sites at around 6 metres above ground. Cotton mice do not hibernate. They enter torpor during the hottest days of the summer months. One of the communication ways in this species is high pitched squeaks and buzzes. When excited, they have been seen to hit their front feet on the ground, producing a drumming sound.
Little is known about the mating system in Cotton mice. They may breed throughout the year, but usually in early spring and fall. Females have four litters a year of up to seven young. The gestation period lasts 23 days in non-lactating females and 30 days in lactating females. Pups are born helpless and naked. Mothers nurse their young until they reach 20-25 days of age. Cotton mice become reproductivley mature at around two months of age.
There are no major threats to Cotton mice at present. However they suffer from fire events through emigration, increase in predation, or from direct damage by fire from loss of habitat/protection.
According to IUCN, the Cotton mouse is locally common and widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today remain stable.
Cotton mice consume fruits in their diet, therefore playing a role in the seed dispersal of different plants. They also eat different insects and this way control population numbers of various pests. Due to a large number of their population and very high reproductive rate, Cotton mice are the main prey species for numerous predators of their habitat.