Small Mammal Communities along Transmission Power Line Rights-of-Way in Deciduous Forests of Québec

Abstract

Powerline right-of-way (ROW) clearing represents, as clearcutting, an important anthropogenic disturbance and few studies have evaluated their impacts on small mammals. In 1995, TransẾnergie initiated a research program on biodiversity in high-voltage powerline rights-of-way (ROWs) in Quebec (Canada). As part of this study, small mammals were trapped in two deciduous forest sites of southern Quebec. The objective of this chapter is to compare small mammal communities between a managed and a non-managed ROW and between the ROW and the adjacent forest of both sites. For each study site, four trapping transects were marked at 15 m intervals from the middle of the ROW to 90 m into the forest. Each transect was divided into four habitats representing the ROW, the edge, the shallow woods, and the deep woods. Traps were run for 5 consecutive days in July and August. A total of 170 small mammals were captured in La Conception whereas 331 small mammals were captured in Windsor. Common shrew, meadow vole, and short-tailed shrew were the dominant species in both ROWs. Pygmy shrew, southern bog lemming, and smoky shrew, three uncommon species in Quebec were also captured in the ROWs. The relative abundance of all small mammals combined, species richness, and species diversity (Shannon index) were similar among the four habitats in both sites. Nine species were captured in the ROW of both managed and non-managed sites. The abundance of all small mammal species combined was significantly higher in the ROW of La Conception than in the Windsor ROW, as in the other three habitats. Species richness and species diversity in the ROW were higher in La Conception compared to Windsor in 2003 but were similar in 2002.