Dynamics of Boreal Birds at the Edge of their Range in the Adirondack Park, NY

Abstract

Abstract The Adirondack Park in northern New York is located at the southern range extent for several bird species that inhabit lowland boreal forest habitats, which in the Adirondacks are naturally fragmented and intermixed with eastern temperate forest types. I examined occupancy dynamics of 8 bird species in lowland boreal forest wetlands, evaluating the influence of variables associated with climate change and habitat fragmentation, including wetland size and connectivity, on colonization and extinction dynamics for the period 2007–2011. Occurrence data from point-count surveys conformed to predictions of metapopulation theory with respect to extinction, with most species more likely to experience local extinction from smaller, more isolated wetlands. Responses to latitude and elevation were variable. Proximity of human infrastructure was the most consistent driver of short-term dynamics across species, with two-thirds more likely to colonize low-impact sites and become locally extinct from more-impac...