Mesopredator Abundance in Oak Forest Patches: a Comparison of Scent Station and Live-trapping Techniques

Abstract

Patch size is of interest in evaluating relationships between nest predation and mesopredator abundance because smaller patches are associated with more edge. I delineated 20 patches of oak forest ranging in size from 0.2 to 55.3 ha within the Oklahoma Crosstimbers Ecoregion, a mosaic of grassland and woodland, with the use of aerial photos and vector GIS. Scent stations and live traps were placed at a density of 0.25 - 0.50/ha within these patches to index mesopredator abundance in the summers of 2003 and 2004. Macrohabitat landscape features correlated with mesopredator abundance included distance to roads (positive relationship) and patch size (negative). Mesopredator relative abundance indices from live trapping and scent stations were not highly correlated in either year of the study. Our evidence that mesopredators within the Oklahoma crosstimbers were more likely to be found in smaller patches of oak woodland has implications to avian nesting success in these patches.