Brush management for improving wildlife habitat in SouthTexas is important because of the economic value of wildlife. We determined vegetation responses to (1) roller chopping of guajillo (AcaciaberIandieriBenth.)-blackbrush acacia (A. rigidulaBenth.)dominated rangeland and (2) heavy dischrg of whitebrush (Aloysia &ioides Cham.)-dominated rangeland to improve white-tailed deer (Odocoileus virginianus Raf.) habitat. Canopy cover of vegetation was estimated seasonally during August 1988 to April 1990. Both treatments reduced brush canopy cover, but herbaceous response depended on rainfall. Mean herbaceous cover was 65 and 136% higher on roller chopped sites than on untreated sites when averaged across all sampllng dates. Heavy diseing reduced relative canopy cover of whltebrush but increased cover of spiny hackberry (Celtis pallida Torr.), an important browse species. Forb species richness was higher on roller chopped and disced sites than on untreated sites, but species diversity was similar. Because herbaceous response to brush removal may depend on rainfall, other factors such as effects on browse availability and nutritional quality may need to be considered when plannhrg brush management strategies to improve white-tailed deer habitat.

Herpetofaunal declines have been documented globally, and southern Florida, USA, is an especially vulnerable region because of high impacts from hydrological perturbations and nonindigenous species. To assess the extent of recent change in herpetofauna community composition, we established a baseline inventory during 1995-97 at a managed preserve in a habitat rich area of southwest Florida, and repeated our sampling methods fifteen years later (2010-11). Nine drift fence arrays were placed in four habitat types: mesic flatwood, mesic hammock, depression marsh, and wet prairie. Trapping occurred daily for one week during 7-8 sampling runs in each period (57 and 49 total sampling days, respectively). Species richness was maintained in mesic hammock habitats but varied in the others. Catch rates of several native species (Anaxyrus terrestris, Lithobates grylio, Anolis carolinensis, Nerodia fasciata) declined significantly. Other native species (Lithobates sphenocephalus, Siren lacertian, and Notophthalmus viridescens piaropicola) that were abundant in 1995-97 declined by greater than 50%. Catch rate of only two species (the nonindigenous Anolis sagrei and the native Diadophis punctatus) increased significantly. Hierarchical cluster analysis indicated similarity within habitat types but significant dissimilarity between sampling periods, confirming shifts in community composition. Analysis of individual species’ contributions to overall similarity across habitats shows a shift from dominance of native species in the 1990s to increased importance of nonindigenous species in 2010-11. Although natural population fluctuations may have influenced differences between the two sampling periods, our results suggest considerable recent change in the structure and composition of this southwest Florida herpetofaunal community. The causes are unknown, but hydrological shifts and ecological impacts of nonindigenous species may have contributed.

Mechanical top growth removal of certain shrub species stimulates sprouting and temporarily htcreases nutritional quality, availability, and yield of browse. We determined the effects of (1) roller chopping separate portions of rangeland, dominated by guajillo (Ace& berlandieri Benth.) and blackbrush acacia (A. rigid& Benth.), during consecutive years and (2) disking separate portions of rangeland, dominated by dense whitebrush (Aloysia &ciodes Cham.) thickets, during consecutive years on white-tailed deer (Odocoileus virginimus Raf.) use of the treated areas. Separate, adjacent portions of guajillo and blackbrush acacia-dominated rangeland were roller chopped in a pattern of alternating treated and untreated strips each year during summer for 4 consecutive years (1985-1988) on an area in Duval County, Tex., and for 2 years (1988-1989) on areas in Duval and McMullen counties, Texas. Whitebrush-dominated rangeland was disced in a similar pattern during 2 years (1988-1989). Twenty percent of each study site was treated each year. Estimated deer density in the rollerchopped area in Duval County was higher than estimated deer density in an untreated area during 1985-1987 and in 1989. Roller chopping in study areas in Duval and McMullen counties increased deer fecal pellet-group densities (groups ha'* day") relative to untreated sites in winter, spring, and summer 1989 and when averaged over the 21-month study. Discing dense whitebrushdominated sites increased pellet-group densities rehttive to untreated sites in spring and summer 1989 and when averaged across the 21-month study period. Increased deer use of treated areas was probably a function of several factors, including increased forb availability and increased nighttime visibility for predator detection.