Small Mammal Survey of Griffith League Ranch, Bastrop County, Texas

Abstract

The Lost Pines Region of Texas, on which the Griffith League Ranch is situated, is characterized by the occurrence of loblolly pines (Pinus taeda), post oaks (Quercus stellata), and blackjack oaks (Q. marilandica) and represents a unique ecosystem in Central Texas. However, little research has been done on the mammalian fauna of this area. My research project surveyed small mammals on GLR using the appropriate field methods, comparing species diversity within and between habitat types across all four seasons. A total trapping effort of 3,570 trap-nights was employed to capture small rodent species and I verified the presence of 15 additional mammals out of the possible 44 native mammalian species previously identified from this region. New records were established for Cryptotis parva, Sciurus carolinensis, Chaetodipus hispidus, and Reithrodontomys fulvescens. The total abundance of rodents at GLR was low (2.5 individuals collected per 100 trap-nights) as were both overall species richness and diversity. This pattern probably is due largely to the low plant diversity, impact of imported red fire ants, and lack of fire management on the property. Peromyscus leucopus was the most abundant rodent at GLR, occurring in all habitat types. Open grassland sites on the property during fall and winter had the highest abundance of small mammals of any of the habitat types trapped at any time (6.0 and 4.7 individuals captured per 100 trap-nights, respectively).