Macro- and micro-habitat associations of small mammals in seral aspen-birch and mature red spruce habitats in Acadia National Park, Maine, were studied by live-trapping during the summers of 1987 and 1988. The aspen-birch habitat was structurally more diverse than the mature conifer habitat, but diversity, richness, and evenness of species of small mammals were not different between habitats. Blarina brevicauda, Sorex cinereus, Tamias striatus, and Peromyscus leucopus exhibited preference for seral hardwoods, whereas Tamiasciurus hudsonicus showed preference for the red spruce habitat. Most species in the aspen-birch habitat exhibited some degree of microhabitat selection and used microhabitat separate from other species. Small mammals in the red spruce habitat were less selective. Microhabitat used by a species and segregation by microhabitat among species varied between years in both habitats and appeared to be related to intraspecific interactions. Microhabitat use by sexes of Clethrionomys gapperi, P. maniculatus, and P. leucopus in the aspen-birch habitat was related to degree of habitat specialization. A spatial simulation system was developed to examine the responses of habitats of B. brevicauda, P. leucopus, T. striatus, and T. hudsonicus over time to varying levels of disturbance in the western section of Acadia National Park. The system consists of a raster-based data base containing descriptors of cover types, and models of vegetative succession and disturbance by windthrow and wildfire. Simulation experiments were conducted without disturbance, under three levels of windthrow, and with two sizes of wildfires (100 and 500 ha) at the three levels of windthrow. Occupancy of available habitat was based on the dispersion of a species during the previous simulation interval, the dispersal distance of a species, and patch size. Habitat for species associated with hardwoods increased with the rate of disturbance. Regardless of disturbance size or rate, each species was able to occupy almost all of its available habitat over a 300 yr period owing to the dispersion of habitat patches created by windthrow. Results suggest that windthrow alone can produce long-term spatial diversity of wildlife habitats in Acadia.
| Identifer | oai:union.ndltd.org:UMASS/oai:scholarworks.umass.edu:dissertations-8153 |
| Date | 01 January 1991 |
| Creators | Garman, Steven Lee |
| Publisher | ScholarWorks@UMass Amherst |
| Source Sets | University of Massachusetts, Amherst |
| Language | English |
| Detected Language | English |
| Type | text |
| Source | Doctoral Dissertations Available from Proquest |
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