title: Intraspecific functional diversity of common species enhances community stability.
abstract: Common species are fundamental to the structure and function of their communities and may enhance community stability through intraspecific functional diversity (iFD). We measured among-habitat and within-habitat iFD (i.e., among- and within-plant community types) of two common small mammal species using stable isotopes and functional trait dendrograms, determined whether iFD was related to short-term population stability and small mammal community stability, and tested whether spatially explicit trait filters helped explain observed patterns of iFD. Southern red-backed voles (Myodes gapperi) had greater iFD than deer mice (Peromyscus maniculatus), both among habitats, and within the plant community in which they were most abundant (their "primary habitat").Peromyscus maniculatuspopulations across habitats differed significantly between years and declined 78% in deciduous forests, their primary habitat, as did the overall deciduous forest small mammal community.Myodes gapperipopulations were stable across habitats and within coniferous forest, their primary habitat, as was the coniferous forest small mammal community. Generalized linear models representing internal trait filters (e.g., competition), which increase within-habitat type iFD, best explained variation inM. gapperidiet, while models representing internal filters and external filters (e.g., climate), which suppress within-habitat iFD, best explainedP. maniculatusdiet. This supports the finding thatM. gapperihad higher iFD thanP. maniculatusand is consistent with the theory that internal trait filters are associated with higher iFD than external filters. Common species with high iFD can impart a stabilizing influence on their communities, information that can be important for conserving biodiversity under environmental change.
authors.affiliation: Department of Wildlife, Fisheries, and Conservation Biology University of Maine Orono ME USA; Present address: Department of Forest and Wildlife Ecology University of Wisconsin-Madison Madison WI USA.
authors.forename: Connor M
authors.identifier: 0000-0002-0235-5214
authors.initials: CM
authors.lastname: Wood
authors.affiliation: U.S. Geological Survey Maine Cooperative Fish and Wildlife Research Unit Orono ME USA.
authors.forename: Shawn T
authors.initials: ST
authors.lastname: McKinney
authors.affiliation: U.S. Geological Survey Maine Cooperative Fish and Wildlife Research Unit Orono ME USA.
authors.forename: Cynthia S
authors.initials: CS
authors.lastname: Loftin
keywords: Community ecology; functional diversity; small mammals; stability; stable isotopes