SWAMP RABBIT
Sylvilagus aquaticus (Bachman 1837)

Order Lagomorpha : Family Leporidae

DESCRIPTION. Largest of the cottontails within its range; pelage coarse and short for a rabbit; upperparts grayish brown, heavily lined with blackish; rump, upperside of tail, and back of hind legs dull ochraceous brown; sides of head and body paler than back, less suffused with blackish; underparts, including underside of tail, white except for buffy underside of neck; front legs and tops of hind feet cinnamon rufous. Averages for external measurements: total length, 534 mm; tail, 69 mm; hind foot, 106 mm; ear, 70 mm. Weight, 1.5–3 kg.

DISTRIBUTION. Found in eastern half of the state, from Montague and Eastland counties in the Cross Timbers region, south and west to Kerr County in the eastern Edwards Plateau region, and south to Aransas and Refugio counties along the Gulf Coast.

SUBSPECIES. Two subspecies historically have been recognized in Texas, S. a. littoralis in the tidal marshes and coastal prairies of southeastern Texas, and S. a. aquaticus over the rest of the species range in eastern and central Texas. The former is allegedly much darker and more reddish brown than the latter, especially on the rump, hind legs, and tops of all the feet. However, in 1974 George Lowery of Louisiana State University demonstrated the reddish-brown coloration results from a ferruginous stain that the marsh-dwelling rabbits pick up from the terrain. Furthermore, he demonstrated that the reddish stain is easily removed by applying oxalic acid. Hence, the alleged redder-brown coloration of the feet of the so-called littoralis is purely adventitious, and this subspecies is not worthy of recognition. Thus, littoralis is a synonym of S. aquaticus, making the latter a monotypic species.

HABITS. The swamp rabbit, as the name suggests, inhabits poorly drained river bottoms and coastal marshes. Well adapted to a semiaquatic habitat in that its dense fur waterproofs its skin, the animal is at home in the water. In fact, it crosses rivers and streams on its own initiative, a habit usually not found in other rabbits in Texas. It is secretive by day and is seldom seen, except when frightened from its bed in some thicket, but its presence in an area is readily disclosed by the piles of fecal pellets deposited on stumps, down logs, or other elevated objects. Along the coast it is at home in cane thickets—hence, the local name "cane cutter"—but in inland areas it is restricted to the floodplains of rivers and streams and their associated tangles of shrubs, trees, and vines.

In southeast Texas, one swamp rabbit per 2.8 ha (7 acres) of poorly drained bottomland is typical. The swamp rabbits frequent a definite local range, which they refuse to leave even when pursued by dogs. They use thickets of briers or brush for protections rather than underground burrows. In southeast Texas both eastern cottontails (S. floridanus) and swamp rabbits occupy the creek and river bottoms in about equal numbers, but in the uplands only eastern cottontails are found.

Little is known of their food habits, although succulent vegetation, including grasses, forbs, and the new shoots of shrubs, are probably important.

The breeding season extends at least from January to September, but the peak is in February and March when green vegetation is available. Possibly two or more litters of two to three young are reared annually. After a gestation period of 39–40 days, the young are born in, or transferred to, surface nests composed of vegetation and lined with rabbit fur or nests in holes in logs and stumps. A nest found at the base of a cypress stump was composed of Spanish moss and rabbit fur; it held six small rabbits. Another nest located under a long, fallen branch of a tree was lined with fur and held two young rabbits. At birth the young are covered with fur, but the eyes and ears are closed. The eyes open and the young rabbit is able to walk in 2–3 days.

Among their known natural predators are the gray fox, great horned owl, and alligator. Doubtless, they are preyed on by many other species. Other than humans, flood waters are a primary cause of mortality.

POPULATION STATUS. Uncommon. Even though the swamp rabbit is distributed throughout the eastern one-third of the state, it seldom occurs in large numbers.

CONSERVATION STATUS. Although the IUCN status is listed as least concern, this species appears to be decreasing in numbers. However, it does not appear on the federal or state lists of concerned species. Optimum habitat in much of the swamp rabbit's range is shrinking with the drainage of wetlands and clearing of hardwood forests; consequently, there is much concern about the future conservation status of this rabbit in Texas. In the Hill Country they are threatened by habitat fragmentation. There is an imperative need to monitor populations in the future.

 

From The Mammals of Texas, Seventh Edition by David J. Schmidly and Robert D. Bradley, copyright © 1994, 2004, 2016.  Courtesy of the University of Texas Press.