Demography of the meadow vole along a simple habitat gradient

Abstract
A population of meadow voles (Microtus pennsylvanicus) was monitored by livetrapping in five different habitat types in eastern Massachusetts for 5 years. An index of grass cover was estimated for each habitat type, and the relationship between population statistics and grass cover was examined. Numbers of voles and survival rates increased rapidly with increasing grass cover until an asymptote was reached. Other population statistics were unrelated to the gradient. Grass cover appears to represent a predictive measure of environmental suitability. The ability to select simple habitat gradients representing suitability should facilitate demographic comparisons of habitat use by sympatric generalists and specialists.