Small mammal sampling protocol for long-term ecological monitoring program.

The small mammal investigations begun in the Rock Creek watershed of Denali National Park and Preserve in 1992 focused primarily on three species: the northern red-backed vole (Clethrionomys rutilis), the tundra vole (Microtus oeconomus), and the singing vole (Microtus miurus). Captures were also recorded of northern bog lemmings (Synaptomys borealis) and shrews (Sorex spp.), but demographic information was not collected on these species. Geographic Description: Rock Creek Watershed in the Denali National Park and Preserve. Denali National Park and Preserve is located in the central Alaska Range, approximately 210 km southwest of Fairbanks, Alaska. Methodology: Two competing trapping methods were employed for the assessment of population changes over time. Trapping grids, described by Otis et al. (1978), are used primarily for the estimation of population abundance, but are adaptable for the estimation of density. With traps in a grid configuration, traps are placed uniform distances apart in lines separated by the same distance as traps within a line, forming a rectangular trap pattern.