Herpetofaunal assemblages of four forest types in the Big Sandy Creek Unitof the Big Thicket National Preserve

Herpetofaunal assemblages were surveyed on four different forest types in t he Big Sandy Creek Unit of the Big Thicket National Preserve in Polk County . Texas. The forest types surveyed wan Floodplain Hardwood, Lower Slope Har dwood Pine, Upper Slept: Pins Oak and Upland Pine. During 1998 and 1999, 18 66 individual amphibians and reptiles of 40 species ware recorded. A Monte. Carlo contingency table analysis demonstrated that the four forest types h eld significantly different herpetofaunal assemblages. Sorenson's coefficie nt of community percentages showed that forest types adjacent to one anothe r along a moisture-elevation gradient had the most species of herpetofauna in common. Soil texture influences vegetation through soil moisture availab ility, and differences in herpetofaunal assemblages seemed to he related to differences in moisture availability among forest types. Greater abundance of amphibians and snakes was found in the: two more mesic forest types in the lower elevations.