Date of Award

12-2002

Level of Access Assigned by Author

Open-Access Thesis

Degree Name

Master of Science (MS)

Department

Wildlife Ecology and Wildlife Conservation

Advisor

William B. Krohn

Second Committee Member

Malcolm L. Hunter, Jr.

Third Committee Member

Mary Kate Beard-Tisdale

Abstract

The three studies reported here (i.e., statewide, southern Maine, and state and federal wildlife areas) identify what areas should be conserved to represent the natural diversity of Maine. Geographic Information System (GIs) technology was used to conduct the analyses comparing the distribution of abiotic and biotic variables representing natural diversity on and off conservation lands. In the statewide analysis, 10 environmental variables were compared on and off conservation lands using ArcGrid with a cell resolution of 1.86 x 1.86 km. The areas found to contain variables that were underrepresented were. combined to identify and map regions with under-represented characteristics. The mean number of under-represented variables for each major biophysical region in Maine was calculated with southern Maine being in greatest need of more conservation lands. The highest degree of under-representation was in low elevation areas and lower portions of large river valleys. When abiotic variables, which are more permanent to the landscape, were weighted higher than biotic, the same results as above were found. To determine locations of potential new conservation lands in southern Maine, I analyzed the representation of seven environmental variables on conservation lands in southern Maine with a cell resolution of 94.6 x 94.6 m. Only four variables were substantially under-represented including 401 - 450 m elevation, 4 - 7 degrees of slope, shoreline and mudflats, and early successional and crop cover types. The distance from these highly under-represented areas to areas with high road density was measured and mapped as an indicator of their vulnerability to development. The contribution of Wildlife Management Areas (WMA's) and National Wildlife Refuges (NWR's) were analyzed to evaluate their contribution to the conservation of Maine's wildlife and natural diversity. Earlier management objectives for these agencies focused on acquisition of game (e.g., waterfowl) and endangered species habitats. Management emphasis has broadened recently to include conservation of ecosystems and all wildlife species, therefore, it is important to assess whether NWR's and WMA's accomplish these new, broader goals. Geographic datasets including topography, vegetation cover, and terrestrial vertebrate richness were compared on and off WMA's and NWR's using ArcGrid with a cell resolution of 94.6 x 94.6 m for each major biophysical region in Maine. Out of 270 terrestrial vertebrate species predicted to occur in Maine, 219 were predicted to occur on WMA's and 223 on NWR's. Wetland and open water vertebrate species, wetland vegetation types, and low elevation areas were over-represented in the state, while most upland vegetation types were under-represented by WMA's and NWR's. These results suggest that WMA's and NWR's should acquire additional mid-elevation and upland areas, assuming a goal of land conservation that is representative of the state's natural diversity.

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