The eastern cottontail (Sylvilagus floridanus) is a species of rabbit in the family Leporidae. It is the most widespread and abundant rabbit species in North America, inhabiting a wide range that extends from southern Canada throughout most of the United States and into parts of Mexico, Central America, and the northern regions of South America. The genus Sylvilagus includes around 15 species of New World cottontail rabbits, which are widespread throughout the Americas.
Subspecies
There are at least 17 recognized subspecies of Sylvilagus floridanus, distinguished mainly by geographic distribution and minor morphological differences. These subspecies are generally grouped by region:
Morphological and genetic variation across populations reflect adaptation to diverse environments, with some populations showing notable differences in size, coloration, and behavior.
The species epithet floridanus means "of Florida," referencing the region where the species was first scientifically identified.
Evolution and phylogeny
The eastern cottontail belongs to the Leporidae family, which includes all rabbits and hares. Within this family, Sylvilagus is a New World genus that diverged from Old World rabbits and hares millions of years ago.
Molecular and morphological studies have identified several distinct species and subspecies within Sylvilagus, highlighting a complex evolutionary history shaped by geographic isolation and environmental adaptation. Separate populations of the eastern cottontail found in different regions display markedly different genetic compositions, which may factor into their adaptability to diverse habitats. This species continues to be an important subject in studies of mammalian adaptation and speciation. It
Description
thumb|alt=A photo of a brown rabbit standing in grass in profile cropped to show only the head|Eastern cottontail in [[Brooklyn, New York, United States]]
The eastern cottontail has a distinctive white spot on its forehead when young and fur that ranges from reddish-brown to grayish-brown, with large hind feet, long ears, and a short, fluffy white tail. Its underside is white, and there is a rusty patch near the tail. It differs from a hare in its overall smaller size and brownish-gray coloring around the head and neck, with a lighter-colored body and a white underside on the tail. During winter, the eastern cottontail's pelage becomes more gray than brown. Kits (young rabbits) develop a similar coloring after a few weeks but are born with a white blaze running down their forehead, which fades as they mature. The species exhibits slight geographic variation in body size, with individuals generally increasing in mass from southern to northern latitudes, in line with Bergmann's rule. For example, adult specimens from the Florida Museum of Natural History have a mean weight of , whereas a study of 346 adults from Michigan found an average mass of .
Range and habitat
thumb|alt=A brown rabbit sitting in snow|Eastern cottontail in winter coat, [[Ottawa, Ontario, Canada]]
The eastern cottontail inhabits meadows, shrubby areas, and edge habitats throughout the eastern and south-central United States, southern Canada, eastern Mexico, Central America, and northernmost South America. It is also present on Margarita Island in the Caribbean. The species is especially abundant across the Midwest of North America, and its range expanded northward as forests were cleared by settlers. In the 1950s and 1960s, the species was introduced to France and northern Italy, where it underwent rapid territorial expansion and population growth. Critical habitat components include dense, well-distributed escape cover interspersed with open foraging areas such as pastures or grasslands.
Eastern cottontails are mostly crepuscular and nocturnal, foraging primarily at dawn, dusk, and night. However, they can be seen during the day, particularly in overcast or foggy conditions.
They spend much of the daytime resting under vegetative cover and often remain motionless for extended periods to avoid detection. In New England, home ranges average for males and for females but can vary between depending on habitat quality and season. Daily movements usually cover only 10–20% of their total range.
thumb|Eastern cottontail in its nest
Nests are usually built in grassy fields, hayfields, or weedy areas near brushy cover. In Iowa, nests were most commonly found within of shrubs in herbaceous vegetation at least tall.
Reproduction
thumb|Litter and nesting material
Eastern cottontails reach sexual maturity at 2–3 months of age. Breeding season varies by latitude and climate, beginning as early as January in the southern United States and around March in New England, continuing through late summer. Mating is promiscuous, with males competing for access to females.
Diet
thumb|left|alt=A rabbit eating clover, turning toward the camera|An eastern cottontail feeding in [[Magee Marsh Wildlife Area]]
Eastern cottontails feed primarily on a wide variety of plants, with some studies documenting 70–145 plant species in their diet. They prefer tender herbaceous vegetation, such as grasses, clovers (Trifolium spp.), crabgrasses (Digitaria spp.), and wild rye (Elymus spp.).
A significant source of mortality is collisions with vehicles. In Missouri, it has been estimated that approximately ten eastern cottontails are killed annually per mile of road, with the peak of highway mortality occurring in spring (March through May), when roadside vegetation greens up before adjacent fields and attracts rabbits to the roadside.
Annual adult survival is estimated to be around 20%. Average lifespan in the wild is about 15 months, though the longest-lived recorded wild individual reached five years. In captivity, eastern cottontails have lived up to nine years. A comprehensive summary of eastern cottontail diseases and parasites is provided by Chapman et al.
Predators
The eastern cottontail is preyed upon by a wide variety of natural and introduced predators, forming a significant part of the diets of many carnivores and raptors in eastern North America. Common predators include domestic cats (Felis catus) and dogs (Canis lupus familiaris), foxes (Vulpes and Urocyon spp.), coyote (C. latrans), bobcat (Lynx rufus), weasels (Mustela spp.), raccoon (Procyon lotor), mink (Neogale vison), great horned owl (Bubo virginianus), barred owl (Strix varia), hawks (particularly Buteo spp.), corvids (Corvus spp.), and various snakes.
Juveniles are rarely taken by short-eared owls (Asio flammeus), and only trace remains of eastern cottontails have been detected in the scat of black bears (Ursus americanus).
Conservation
The eastern cottontail species, due to its abundance and large, expanding range, is not considered to be under any threat. Individual populations may face local habitat loss. The species is considered "secure" by NatureServe and is listed as least-concern by the International Union for Conservation of Nature.