Effects of Interstate 95 on Breeding Birds in Northern Maine

Abstract

The effects of 2-lane and 4-lane highways on forest birds were examined along Interstate 95 (1-95) in northern Maine during 1975-77. Total numbers of breeding birds in forest areas near the highway were not significantly different from those at greater distances. Four species were less abundant near the highway, after accounting for variations in habitat, and 6 other species were more abundant. Addition of species nesting along the forest-right-of-way (ROW) edge caused a slight increase in species richness and diversity. The ROW and median strip along 4-lane highway supported half as many breeding birds as an equal amount of forest habitat. Densities of breeding birds in the ROW along 2-lane highway were 79% of those in forest habitats. J. WILDL. MANAGE. 43(2):421-427 The influence of a highway on wildlife begins with destruction of habitat, as pavement and grass replace existing plant communities. Where these are forest communities the change is dramatic, and for forest wildlife the area may no longer be suitable. Subsequent use of the highway may disturb certain species of wildlife in areas near the road, rendering additional habitats unsuitable. On the other hand, habitats created in the rightof-way (ROW) and developing along the forest-ROW edge may support species not present in forest communities. This study examined the effects of 1-95 on breeding bird populations in forest habitats in northern Maine. The objectives were to determine: (1) the size of the population lost through removal of forest habitat encompassed by the highway and ROW; (2) whether highway use caused a change in bird populations in forest habitat outside the ROW; and (3) which species, if any, were adversely or favorably affected by the highway. I am grateful to the Maine Department of Transportation for financial and technical assistance. V. B. Richens, M. W. Coulter, R. B. Owen, Jr., and R. C. Eckhardt, of the University of Maine at Orono, provided editorial assistance. The following persons helped collect field data: Nona Famous, Norman Famous, Linda Wright, Wesley Wright, and Deborah Palman. This paper is a contribution of the Maine Cooperative Wildlife Research Unit: U.S. Fish and Wildlife Service, Maine Department of Inland Fisheries and Wildlife, University of Maine, and Wildlife Management Institute, cooperating.