Stable Isotope Analysis of Fall Migration Stopover by Six Passerine Species in an Inland Pitch Pine-Scrub Oak Barren

Abstract

Abstract We conducted mist-net surveys of migrating songbirds during fall migration 2007–2009 on the 1,300-ha Albany Pine Bush Preserve (APBP), a fire-managed inland pitch pine–scrub oak (Pinus rigida–Quercus spp.) barren in east-central New York. We banded 244 migrating passerines from 32 non-resident species in 8,610 net/m/hr documenting use of northeastern pine barrens as stopover sites for passerines with diverse breeding ecologies. We estimated the breeding site origin of six species (a kinglet, four warblers, and a sparrow) using stable hydrogen isotope measurements from flight feathers. There was a broad range of isotope ratios within each species indicating a large catchment area extending several hundred kilometers north and west of the stopover site. Over half the birds originated >750 km from the APBP. We found no evidence for geographical structure of the timing of migration through APBP; slopes of regression lines for capture date versus hydrogen isotope ratio from feathers (δDf) were not sta...