Mammal Inventory of the Appalachian Trail in Maine

Doherty, Molley

The National Park Service (NPS) Inventory & Monitoring (1&M) program involves conducting inventories to document occurrence (presence/absence), and under certain circumstances, a variety of abundance categories for vertebrates and vascular plants (NPS 1999). Using existing verifiable data (e.g., voucher specimens) and field investigations, this effort will attempt to document 90% of the terrestrial mammal species expected to occur within park boundaries (NPS 1999). This information may be used to develop monitoring strategies for select species that will be conducted as part of a long-term monitoring program. Small mammals (e.g., mice, voles, and shrews) comprise more than 50% of the at risk (i.e., rarity ranks of S1, S2, or S3) mammals in Appalachian Trail (AT) states. Small mammals will likely have strong habitat associations with the AT corridor, especially with high elevation areas and boreal relict forests. Management of the AT corridor could have direct impacts on the life history requirements of many small mammals because of their generally small home ranges. Small mammal species, particularly those "at risk", have not been comprehensively surveyed within the AT corridor. The Natural Heritage surveys conducted on the AT from 1991 — 2000 identify Element Occurrences (EO) of some mammal species, but do not reflect the range of diversity nor the distributional extent of individual small mammal species. Because the monitoring of at risk species populations will likely become an important component of an AT Ecological Monitoring program, it is imperative to fill the gaps in knowledge for the most critically imperiled species likely to occur within the AT corridor. Given the dominance of this group of species, additional inventory efforts to document the presence of at risk small mammals within the AT corridor is warranted. To begin to address this goal, we will conduct inventory efforts that focus on expanding knowledge of at risk small mammal species identified during prior natural heritage inventory work. The areas of concern are those parts of the AT corridor that are located in Maine. The inventory will attempt to sample and identify the occurrences of as many species as possible even though the inventory methods and sampling procedures will be chosen to increase the likelihood of detecting the target species.