ECOLOGY OF SMALL MAMMALS, VEGETATION, AND AVIAN NEST SURVIVAL ON PRIVATE RANGELANDS IN NEBRASKA

ABSTRACT—Small mammals can be an important bioindicator of ecosystem health. They serve as both predator and prey in many ecosystems. By means of live trapping and nest monitoring, we studied the ecologi-cal relationships between small mammals, avian nest survival, and vegetation composition and structure on six private ranches in the Sandhills of Nebraska during 2004. Our study documented six species (132 captures) of small mammals, and we monitored 139 bird nests. Pastures with high small-mammal populations did not suffer higher nest mortality, indicating that small-mammal abundance does not predict avian productivity. We found several vegetation characteristics that influenced small-mammal abundance on our sites. Small-mammal cap-ture indices declined with increased percentage of lying-litter cover in pastures. Long-duration grazing systems had higher small-mammal indices than medium- or short-duration grazing systems, and proximal pastures had higher similarity indices for both birds and small mammals. Our study shows that landowners can affect the small-mammal community through grazing management. Key Words: daily nest survival, grassland, grazing, Nebraska Sandhills, small mammal