first great center of logging and lumbering production 

 in Louisiana (Stokes 1954). 



Industrial lumbering was helped by the expansion 

 of the railroad in Louisiana and the introduction of 

 the steam logging engine and puUboat. The problem 

 of timber removal was solved with these inventions. 

 To utilize the new inventions, lumber companies 

 dredged canals to the logging sites. A main canal was 

 8 to 9 m (25 to 30 ft) wide with access channels cut 

 at right angles from the main channel. Among the 

 access channels pullboats could be set to drag the 

 timber from the swamp to the canal. The result was 

 generally a north to south or east to west patchwork 

 of connecting canals with fanshaped paths radiating 

 outward from the canals (Davis 1975). This pattern 

 can still be detected on aerial photographs. By 1925, 

 virtually aU virgin cypress had been removed from the 

 forested swamps of the Chenier Plain. 



4.6.2 CONSUMERS 



The swamp forest habitat is spatially hetero- 

 geneous because of elevation differences and because 

 of the perennial woody vegetation. Thus, niche space 

 is available not only for aquatic species, but also ter- 

 restrial and arboreal species. 



Amphibians and reptiles are represented by 18 

 and 32 species respectively (appendix 6.3). The 

 number of bird species in the swamp forest habitat is 

 exceeded only by the number of species found in rice 

 fields and impounded marshes. Bird richness is rather 

 low during the winter, but during spring and fall mi- 

 grations it is relatively high. This reflects, in part, the 

 seasonal nature of the habitat. The many deciduous 

 trees support large numbers of herbivorous insects 

 during the warmer months and insectivorous birds 

 make up a considerable portion of the community at 

 this time. Mammal species richness is relatively high, 

 with species such as squirrels and bats present. 

 Population levels of nutria, muskrat, and otter are 

 unknown. 



After the logging of the virgin baldcypress at the 

 turn of the century, dense stands of tupelo developed. 

 With an increase in the amount of tupelo came an 

 increase in the forest tent caterpillar (Malacosma 

 disstria). Eggs, laid in June on tupelo branches, hatch 

 the following April. The caterpillars grow to about 

 two inches while consuming the leaves and flowers on 

 the tree. By early May the trees are often bare. In 

 1974, 202,343 ha (500,000 a) of tupelo forests in 

 Louisiana were defoliated. 



Reichle et al. (1973) reported that the timing of 

 this insect's feeding spree is important to the survi- 

 val of the tree. Early leaf production is supported by 

 carbohydrate reserves, while later in the season, pro- 

 duction depends on the photosynthetic biomass. 

 Therefore, early spring fohage consumption may have 

 a smaUer effect on the total year's production than 

 late defoliation. Even though the trees may not be 

 killed, they are affected by this annual defoUation. 

 Morris (1975) reported that studies in Alabama have 

 shown five-year growth losses of 70% or more for 

 tupelo stands defoliated each year. 



This caterpillar defoUation was of little concern 

 until recently because much of the tupelo forests 

 were inaccessible. However, as the demand for tupelo 

 wood increases, stumpage prices increase, and as new 

 mechanized equipment is developed, the forest may 

 need to be protected from the forest tent caterpillar 

 to insure larger quantities of good quahty wood 

 (Morris 1975). 



Other grazers in the swamp forest include deer, 

 rabbits, squirrels, mice, and seed-eating birds. The 

 swamp forest provides an optimum habitat for grey 

 squirrels but is of only fair quality for deer. At 

 times, it is extensively used by wood ducks and mal- 

 lards. Swamp forests also harbor large numbers of 

 wintering song birds (Coastal Ecosystems Manage- 

 ment, Inc. 1975). 



Important detritivores in the swamp forest 

 habitat include insects, Crustacea, microbiota, and 

 fungi. From studies in the cypress swamps of La- 

 fourche Parish, Louisiana, Thomas (1975) asserted 

 that crayfish {Procambarus clarkii) are more important 

 than amphipods in the breakdown of leaf litter. 

 Cellulose-decomposing bacteria present in swamp 

 sediments, likewise, play a key functional role in the 

 mineralization of woody materials. 



Carnivores in the swamp forest system include 

 spiders and voracious insects, such as dragonflies and 

 waterbeetles, that feed on other insects; reptiles, such 

 as snapping turtles, snakes, and alligators; mammals 

 ranging in size from bats and shrews to bobcats and 

 otters; and insectivorous birds and raptors, especially 

 barred owls. Less frequently seen birds such as the 

 red-shouldered hawk, barn owl, and hairy woodpecker 

 also inhabit these forests. 



4.7 MANAGEMENT OF CHENIER PLAIN 

 COASTAL WETLANDS 



As long as humans have hved in the coastal zone 

 they have used and modified its resources. They have 

 built levees for flood protection, canals for navigation 

 and mineral extraction, impoundments for agricul- 

 tural and residential use, and they have discharged 

 sewage and other poUutants into coastal waters and 

 wetlands. These changes have occurred in addition to 

 the natural processes of subsidence, erosion, deposi- 

 tion, and river meander that characterize this naturally 

 dynamic area. 



4.7.1 PRESERVATION OF THE ENVIRONMENT 



As an objective for wetland management, preser- 

 vation of the environment is the most restrictive. Its 

 purpose is to preserve the environment in as natural 

 a state as possible. In the Chenier Plain no wetland 

 area is managed strictly for this purpose. However, 

 Shell Keys National WUdUfe Refuge located offshore 

 of Vermilion Bay is managed for preservation. This 

 refuge, established in 1907, is a 3.2 ha (7.9 a) island, 

 used primarily as a nesting area for marine birds. No 

 hunting, trapping, or disturbance of wildlife is 

 allowed. The land is not to be altered by man in any 



187 



