Inventory of Small and Large Mammal Diversity in a Fragmented Landscape: A Baseline for Investigating Ecological Impacts of Human Disturbance

Abstract

Systematic study of biological diversity is a prerequisite for understanding the ecological effects of climate instability and human disturbance. Our study is part of the Rugar Woods All Taxa Biological Inventory (ATBI) project, which seeks to document the biodiversity of Rugar Woods. We performed a field survey to inventory small and large mammals within Rugar Woods, a 50-acre, temperate, mixed forest. We collected five replicate measurements of both track and stride length and width, as well as photo-documented and georeferenced each track. All observations of sign were inventoried in a database and spatially explored with the iNaturalist application. We recorded ten mammal species, from five families. The most frequently recorded species were weasels (Mustelidae), including long-tailed weasel, fisher, river otter, and mink. We recorded a red fox (Canidae), white-footed mouse (Rodentia), beaver (Rodentia), and grey squirrel (Rodentia), a raccoon (Procyonidae), and white-tailed deer (Cervidae). Mammal tracks were commonly recorded on the ice of the Saranac River where domestic dog tracks were infrequent, and open space likely facilitated animal movement. A majority of tracks were recorded from riparian emergent and scrub-shrub habitats. These habitats are ecologically productive, and are thus integral components of the predator-prey food web. Because of the impending removal of the Imperial Dam, our data provide an important baseline for studying the cascading ecological effects of dam removal. Additionally, the documented mammal species are an essential part of the forest community, and their presence in a fragmented urban forest is encouraging. Finally, many are also disease vectors (e.g., Lyme disease and rabies), thus understanding their habitat use patterns is vital for ecological epidemiology.