5.0 Chenier Plain Animal Species 



5.1 INTRODUCTION 



Part 5 presents a brief description of some of the 

 more common or important animal species that inhabit 

 the Chenier Plain. More detailed information is avail- 

 able from the cited references. 



5.2 MAMMALS 



5.2.1 SWAMP RABBIT (SyhUagus aquaticus) 



The swamp rabbit thrives best in habitats that 

 provide a good mixture of resting, travel, and escape 

 cover (Bryant 1954). Pastures, levee banks, swamps, 

 marshes, and shrub-covered fields provide such cover 

 (Bryant 1954, Hastings 1954, Lowery 1974b). During 

 periods of high water, swamp rabbits need access to 

 elevated areas. Saltmeadow cordgrass lightly inter- 

 mixed with wax myrtle less than 1.2 m (4 ft) high is 

 suitable habitat for the species in the Chenier Plain 

 (Gould 1974). 



The home range (2 to 8 ha or 5 to 19 a) for 

 swamp rabbits varies seasonally (Lowe 1958, Hunt 

 1959, Gould 1974). The species is normally active 

 during the early morning and late evening hours (Gould 

 1974). 



Daily food consumption of the swamp rabbit is 

 about 1 kg (2.5 lb) of vegetation (Richardson 1963). 

 A variety of herbaceous and woody plants are eaten 

 (Svihla 1929, Bryant 1954, Toll et al. 1960, Croft 

 1961, Richardson 1963, Sullivan 1966, Lowery 

 1974b). Important plant foods reported for Louisiana 

 swamp rabbits include white dutch clover, bermuda 

 grass, carpet grass, foxtail grass, bahia grass, dallis grass, 

 giant ragweed, cocklebur, beggarweed, dichondra, 

 bicolor lespedeza, common lespedeza, goosegrass, vasey 

 grass, and buttonweed (Bryant 1954). 



There are no reports which indicate that a special- 

 ized habitat is necessary for mating. Nesting occurs in 

 relatively dry, undisturbed areas. Nests are slight 

 depressions in the ground filled with a mixture of grass 

 and fur. 



The major factor affecting swamp rabbit popula- 

 tions is habitat destruction by livestock overgrazing, 

 land clearing operations, and clean-farming practices 

 (Hastings 1954, Sims 1956). 



5.2.2 COTTONTAIL (Sylvilagus floridanus) 



An area where a mixture of cropland, grassland, 

 woodland, and brush are about equally represented is 

 good cottontail habitat (Hastings 1954). Such areas, 

 however, are few in the Chenier Plain and the cotton- 

 tail rabbit is not abundant. According to Ted Joanen 

 (pers. comm. January 1978, Rockefeller Wildlife 

 Refuge, Grand Chenier, La.), the species has never been 

 observed on any of the cheniers. 



Cottontails are most active during the early morn- 

 ing and late evening hours. They occupy a home range 

 which varies in size from 0.2 to 3 ha (0.6 to 8 a), 

 depending on seasonal changes in habitat 

 (Bruna 1952). No data are available on daily and 

 seasonal movements for this species on the Chenier 

 Plain. 



The cottontail consumes about 1 kg (2.4 lb) of 

 vegetation daily (Richardson 1963). Preferred foods are 

 the same as those reported for the swamp rabbit 

 (Bryant, 1954). 



No specialized breeding or nesting areas have been 

 reported for cottontails. Lowery (1974b) described the 

 nest as a small depression in the ground filled with a 

 mixture of grass and fur, usually in a dense grass clump 

 beneath a stand of taUer vegetation. 



Overgrazing by livestock, land clearing, and clean- 

 farming decrease the amount of suitable habitat, 

 thereby reducing rabbit numbers. 



5.2.3 MUSKRAT {Ondatra zibethicus) 



Suitable muskrat habitat must provide food, 

 water, and sites for constructing burrows or lodges. In 

 the Chenier Plain, these conditions are best provided in 

 brackish marsh, and in rice-growing areas (Arthurl931, 

 O'NeU 1949,Palmisano 1972b). 



In marshes, muskrats will buUd a lodge from marsh 

 vegetation. They will often construct underground 

 burrows in levees or bayou banks. The lodges or 

 burrows form the central area of activity from which 

 animals disperse at night for feeding. In favorable 

 habitat where Olney's three-corner grass is abundant, 

 the species occupies a small home range. In south- 

 western Louisiana, tagged muskrats were recaptured 

 within 100 m (328 ft) of their home site after one year 

 (O'NeU 1949). 



Movements other than those associated with feed- 

 ing have been noted. Juvenile muskrats leave their den 

 when they are sexually mature and travel several kilo- 

 meters before establishing a new home site (O'Neil 

 1949). In rice-growing areas, muskrats often vacate 

 burrows in adjacent irrigation canals and construct 

 lodges in flooded rice fields (O'Neil 1949). 



Properly managed impounded marshes can also 

 provide excellent muskrat habitat. Over 25,000 musk- 

 rats were trapped from a 400 ha (988 a) impoundment 

 containing Olney's three-corner grass near the western 

 shore of Vermilion Bay during the 1976-77 season (R. 

 G. Linscombe, pers. comm. Louisiana Wildlife and 

 Fisheries Department). 



Muskrats consume about one-third of their weight 

 in food each day (O'Neil 1949). Marsh populations of 

 Chenier Plain muskrats feed predominantly on Olney's 

 three-corner grass, whereas populations living in rice 

 fields consume mostly rice and crayfish during spring 

 and summer, and rushes, cattail, clover, and maiden- 

 cane during the winter (O'Neil 1949). 



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