These forested communities have been, and continue to be, impacted by silvicultural practices, habitat fragmentation, and changes in the fire regime. Silvicultural practices, including short rotations, site preparation, and species conversion have greatly altered forest structure and patterns of biodiversity. Intensification of silvicultural practices, primarily fertilization and control of competition using herbicides, will increase impacts in the future. Fragmentation, already substantial, may increase with increased demand from alternative land uses. The altered fire regimes have already resulted in massive changes in forest structure, with implications for regional biodiversity. Socio-economic factors threaten additional changes in fire regimes, or even complete elimination of prescribed burning on increasing portions of the landscape. Ecosystem management cannot be implemented in the absence of knowledge of the interactions of these factors, and the response of individual species and plant and animal communities to these impacts.

In the southeastern United States high diversity and abundance are characteristic of both amphibians and reptiles. Approximately 50 species of snakes occur in the region, and many are abundant. They serve as potential predators on a wide diversity of small vertebrates and large invertebrates and as prey for other predators. Human land use practices have the potential to impact snake faunas in many ways. As a result of such impacts, many species are currently included on TES species lists. Management and recovery of these species requires knowledge of their basic biology and factors determining population trends. Ecosystem management, in turn, requires attention to the conservation and management of snakes and other herpetofaunal species due to their abundance and contribution to biodiversity and ecosystem processes in the southeastern United States.

Research on two West Gulf Coastal Plain TES species has provided a more complete understanding of the impacts of silvicultural and other land use practices on their populations. Timber rattlesnakes (Crotalus horridus) are characteristic of forested ecosystems supporting tree squirrel (Sciurus spp.) populations. Increasing road density fragments forested habitats and snake populations and results in increased snake mortality that may lead to population extirpation. Consequently, silvicultural practices can impact populations directly. Louisiana pine snakes (Pituophis ruthveni) are possibly one of the rarest vertebrates in the United States, and the probability of listing under the Endangered Species Act is high. They are restricted to sandy, well drained soils, generally in longleaf pine habitat. Populations and distribution, based on the limited data available, are declining and fragmented. Louisiana pine snakes are closely associated with pocket gophers, which serve as their primary prey and provide burrows that are their primary sites of hibernation and shelter. Alteration of the fire regime (e.g., by lengthening the interval between burns) can lead to declines in herbaceous vegetation that supports pocket gopher populations, which in turn lead to population declines of Louisiana pine snakes.

Vehicular traffic on roads kill large numbers of snakes and other amphibian and reptile species. Habitats are becoming increasingly fragmented by developing road networks. The population consequences of this mortality are essentially unknown. In eastern Texas, preliminary data suggest that highways and Forest Service system roads can significantly impact snake populations up to several hundred meters from roads. Data suggest that mortality on roadways is substantial both for Louisiana pine snakes and timber rattlesnakes. The population consequences of this mortality are not well understood for these and other herpetofaunal species.

Off-road vehicle use of forested ecosystems is increasing in the southeastern United States, including national forest lands. This is becoming a significant management issue on public and private holdings. While off-road vehicle use results in herpetofaunal mortality, including Louisiana pine snakes and timber rattlesnakes, the impact of this mortality on populations is essentially unknown. Management of off-road vehicle use of forested habitats requires knowledge of population impacts and possible mitigation measures.

The biology and status of the alligator snapping turtle (Macroclemys temminckii), a TES species, is poorly known. Potential and known impacts include land use changes, alteration of aquatic systems, and harvesting for human consumption. Data from the eastern portions of the range suggest that significant population declines have occurred. Effective management of this species requires additional data on habitat use and current status.

The construction of wildlife ponds on national forest land to provide water sources for game species is a common practice. Amphibians, including TES species, use these ponds in Texas. However, the extent of use and population consequences of this use is unknown. There is also a lack of data relating to successional patterns following pond construction, habitat relations within ponds, and other basic attributes of these ponds as they relate to amphibian use.

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