taken on six successive days in August of 1940 near 

 Hackberry (Cameron Parish). Penn considered them to 

 be ". . . exceedingly abundant along the marsh bayou 

 ridges," and described the ridges as ". . . sand and shell 

 ridges, locally known as 'cheniers,' with live oak and 

 palmetto . . ." Liner (1954) cited six specimens from 

 Vermilion Parish, but gave no specific localities. Giles 

 and Childs (1949) and Valentine et al. (1972) reported 

 cottonmouths in the stomachs of aUigators taken on 

 Sabine National WildUfe Refuge. Keiser (1976a) found 

 Atchafalaya Basin cottonmouths in almost any aquatic 

 related habitat, including cottonwood-willow-sycamore 

 forests, cypress-tupelo lowland forests, upland decidu- 

 ous hardwood forests (on Belle Isle), rarely flooded 

 and frequently flooded bottomland hardwood forests, 

 levees, various forb and grass complexes, sand bars, 

 mud flats, treeless ridges and spoil banks, tidal ditches, 

 freshwater marshes, bayous, canals, shallow woodland 

 streams, woodland pools and ditches, isolated ponds 

 (farm and marsh), freshwater lakes, and on floating 

 hyacinth mats. Keiser did not find them in the open 

 waters of AtchafalayaBay or the Atchafalaya River, but 

 specimens were observed on shorelines peripheral to 

 these aquatic habitats. Amy (1948), in a report on the 

 herpetozoans of Delta National Wildlife Refuge, noted 

 cottonmouths 'in all the main types of communities 

 from the river [Mississippi] to the Gulf.' Specific habi- 

 tats mentioned included ridges, willowless marshes, alli- 

 gatorweed, muskrat rows. Gulf side of a mangrove 

 ridge, and piles of drift. 



Cottonmouths rarely utilize high salinity habitats. 

 Wharton (1966) states, 'Cottonmouths apparently 

 enter salt water only by accident or following distur- 

 bance by man; thus the sea as a food source is not uti- 

 lized directly.' Since established freshwater popula- 

 tions may exist on Gulf islands (e.g.. Marsh Island. 

 Chandeleur Islands) and in coastal areas immediately 

 adjacent to saline waters, occasional saltwater transients 

 can be expected. Furthermore, individuals rafting on 

 debris, hyacinth mats, etc., may easily be transported 

 into situations unfavorable for extended survival. 

 Regardless of these exceptions, it is apparent that there is 

 an inverse correlation between population levels and 

 salinity levels in Chenier Plain aquatic habitats. 



Most natural habitats in the Chenier Plain sustain 

 suitable escape cover. Vegetated higher ground (e.g., 

 cheniers, levees, and spoil banks) provide cover during 

 cooler months and protection during flooding and 

 hurricanes. Animal burrows such as those of annadil- 

 los and crayfishes are often utilized as escape routes 

 and overwintering sites. Logs, piles of boards, and 

 other debris, if remaining in place for several months, 

 will often attract these snakes in considerable num- 

 bers. Keiser (1976a) recommended cottonmouth 

 management based, in part, on cover-high ground 

 relationships. 



The cottonmouth will eat almost any flesh, in- 

 cluding carrion. It has been termed an 'opportunistic 

 omni-carnivore' by Burkett (1966). Fishes, amphibians 

 (particularly frogs), reptiles (mainly lizards and 

 snakes), birds, small mammals, mollusks, and arthro- 

 pods are readily consumed. Cannibalism has been re- 

 ported. Conflicting reports exist concerning whether 



or not gravid females will feed in the wild. Cotton- 

 mouths forage for food by day and by night, and they 

 will capture prey under water, on the surface of water, 

 on land, and even in trees and bushes (Barbour 1956). 



The cottonmouth feeds on a wide range of ani- 

 mals. Penn (1943) found two young cottonmouths in 

 the stomach of an adult. Keiser (1976a) found sun- 

 fish, frogs, water snakes, and shrews in Atchafalaya 

 Basin specimens. Fish were the most abundant prey 

 items found by Kofron (1976). 



Cottonmouths normally inhabit reasonably per- 

 manent bodies of freshwater, at low elevations in 

 subtropical climates. 



5.4.3 SNAPPING TURTLE (Chelydra serpentina) 



Virtually nothing is known about the daily and 

 seasonal movements of snapping turtles in the Chenier 

 Plain. Liner (1954) reported juvenile and adult turtles 

 moving into highways and being killed by automobiles 

 in southwestern Louisiana. 



Studies done in other parts of the country indi- 

 cate that the species is highly mobile at times. An 

 early study in Illinois (Cahn 1937) indicated that 

 individuals move considerable distances overland 

 during the summer, and that these journeys were not 

 necessarily associated with nesting or with the drying 

 of ponds. Cagle( 1944) reported that both seasonal and 

 forced migration occurred in the species. Distances 

 traveled by 107 turtles in marshes of South Dakota 

 ranged from to 6.03 km (0 to 3.75 mi) and averaged 

 1.61 km (1 mi) in a period of from 1 to 3 years 

 (Hammer 1969). Evidence suggests that adult turtles 

 utilize the sun as a directional guide during overland 

 travels (Gibbons and Smith 1968). Other papers on 

 movements of snapping turtles include those of Carr 

 (1952), Tinkle (1959), Gibbons (1970), Froese 

 (1974), Froese and Burghardt (1975), and Ewert 

 (1976). 



Little is known concerning the distribution and 

 habitat requirements of Chenier Plain snapping turtles. 

 Penn (1943) termed these turtles 'common' in the 

 marshes of Sabine National Wildlife Refuge near 

 Hackberry, Louisiana, but Cagle and Chancy (1950) 

 failed to capture specimens in 408 trap hours at the 

 Sabine Refuge or 456 trap hours in the marshes of 

 Lacassine Refuge. Brown (1950) included snapping 

 turtles on his list of Te.xas Coastal Prairie Region spe- 

 cies, but his species discussion mentioned only one 

 locality ('Orange' in Orange County). Liner (1954) 

 noted a single specimen from Vermilion Parish, Loui- 

 siana, but gave no specific locality data. Map 42 of 

 Raun and Gehlbach (1972) indicates records for 

 Orange and Jefferson Counties on the Texas Gulf 

 coast. 



Ernst and Barbour (1972) noted: 'The snapping 

 turtle is one of the more aquatic species of turtle. It 

 spends most of its time lying on the bottom of some 

 pool or buried in the mud in shallow water with only 

 its eyes and nostrils exposed. The depth of the water 

 above the mud is usually comparable to the length of 

 the neck. The turtle also hides beneath stumps, roots. 



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