Forest structure in urban parks: effects of on eastern chipmunk distribution (original) (raw)
2001, Northeast Wildlife
To effectively manage eastern chipmunk (Tamias striatus) populations in urban environments, an understanding of chipmunk habitat relationships is needed. Although anecdotal information suggests that the distribution of chipmunks is nonrandom in urban parks, no quantitative data are available, hindering conservation efforts. Thus, our objective was to examine the importance of forest structure to chipmunk distribution at the park and site (i.e., within-park) levels. During spring and summer 2001, we live-trapped chipmunks in 5 New York City (NYC) parks and quantified forest structure. Parks containing chipmunks had greater overstory and understory tree size, and lower shrub stem, stump, and snag densities than parks without chipmunks, with shrub stem densities and litter depth being of greatest importance. Within parks containing chipmunks, increased overstory tree size and herbaceous ground cover characterized sites with chipmunks, with overstory tree size being of primary importance. Although other factors may play a role in chipmunk distributions, our results indicate chipmunks in urban parks prefer mature forest with large trees, few stumps and snags, an open shrub layer, and abundant herbaceous ground vegetation. Thus, habitat management for chipmunks should focus on enhancing large mast-producing trees, opening the shrub layer, and providing herbaceous ground and litter cover.