Data from: Artificial light at night confounds broad-scale habitat use by migrating birds

With many of the world's migratory bird populations in alarming
decline, broad-scale assessments of responses to migratory hazards may
prove crucial to successful conservation efforts. Most birds migrate at
night through increasingly light-polluted skies. Bright light sources can
attract airborne migrants and lead to collisions with structures, but
might also influence selection of migratory stopover habitat and thereby
acquisition of food resources. We demonstrate, using multi-year weather
radar measurements of nocturnal migrants across the northeastern U.S.,
that autumnal migrant stopover density increased at regional scales with
proximity to the brightest areas, but decreased within a few kilometers of
brightly-lit sources. This finding implies broad-scale attraction to
artificial light while airborne, impeding selection for extensive forest
habitat. Given that high-quality stopover habitat is critical to
successful migration, and hindrances during migration can decrease
fitness, artificial lights present a potentially heightened conservation
concern for migratory bird populations.