[6] Sylvilagus aquaticus fossils have been identified as early as the Pleistocene epoch, according to a 1940 discovery of molar teeth found in a Missouri deposit dating back to that era.

[7] It is most abundant in Alabama, Mississippi, and Louisiana, but also inhabits South Carolina, Arkansas, Tennessee, Texas, Oklahoma, Missouri, Kentucky, Illinois, Indiana, and Georgia.

[7] Swamp rabbits spend much of their time in depressions which they dig in tall grass or leaves, providing cover while they wait until the nighttime to forage.

Snow cover has shown to increase swamp rabbit mortality by almost two times in the northern extent of their range.

[7] The head and back are typically dark or rusty brown or black, while the throat, ventral surface, and tail are white, and there is a cinnamon-colored ring around the eye.

[6] Swamp rabbits maintain social order through displays of dominance, and communicate directly through vocalizations such as squeaks, chirps, squeals and alert calls.

[6] Swamp rabbits are herbivorous; they eat a variety of foraged plants, including grasses, sedges, shrubs, tree bark seedlings, and twigs.

[4] A study has found that the preferred foods of S. aquaticus are savannah panicgrass (Panicum gymnocarpum), false nettle (Boehmeria cylindrica), dewberry (Rubus trivialis) and greenbrier (Smilax bona-nox).

[11] The nests in which the young are born consist of a slight depression in the earth that is filled with grasses mixed with rabbit hair.

The occurrence of embryo resorption has been seen in S. aquaticus; this loss of in-utero litters is attributed to some type of habitat disturbance such as flooding, which may cause overcrowding to occur,[11] as well as directly inducing the release of stress hormones.

[17] Even though their swimming abilities[18] lack the speed to escape a pack of hunting dogs, swamp rabbits elude pursuers by lying still in the water surrounded by brush or plant debris with only their nose visible.

[7] Swamp rabbits have several adaptations to avoid predators: cryptic coloration, "freezing", and rapid, irregular jumping patterns.

B. lepori is also known to affect the eastern cottontail,[20] and is suspected as an agent of human Brugia infections in the northeastern United States.

[22] The rabbit is hunted in its native range, both for its products (meat and fur) and for sport, which has been noted as not significantly affecting populations.