American Woodcock Singing-ground Surveys in the western Great Lakes region: assessment of woodcock counts, forest cover types along survey routes, and landscape cover type composition.

Abstract

Overview: Counts of American woodcock (Scolopax minor) on the annual Singing-ground Survey (SGS) have undergone long-term declines in both the Eastern and Central Management Regions. However, interpreting these trends is confounded by a lack of information regarding the relationship between counts and habitat. Therefore, I assessed the relationship between woodcock counts and land-cover composition along survey routes using an Information-Theoretic modeling framework. The amount of early successional forest, open space, and a landscape metric Interspersion and Juxtaposition Index (IJI) best explained counts in Wisconsin; in Minnesota, the amount of mature forest, water and models that included open space, wetlands, and early successional forest together best explained counts. These results are, in general, consistent with woodcock-habitat relations described in published literature, and suggest that woodcock counts along SGS survey routes in Minnesota and Wisconsin reflect the amount and composition of land cover along routes, especially the amount and juxtaposition of early successional forest and open space, which were the variables included in competing models for both states. Key Words: shorebird, American Woodcock, Scolopax minor, Central Management Region, Minnesota, Wisconsin, land cover.