Nest-Site Selection and Breeding Ecology of the Cerulean Warbler in Southern Indiana

Abstract

Abstract Setophaga cerulea (Cerulean Warbler) has been deemed one of the fastest-declining wood warblers in North America. Recent field studies have focused on understanding breeding requirements across its range and other natural life-history characteristics. During 2010–2011, we conducted a breeding study in Indiana to ascertain reproductive success and document nest-site characteristics associated with 22 nesting locations. We also documented breeding phenology and feeding rates during the nestling stage. Cerulean Warblers had a preference for nesting in Quercus alba (White Oak). Nesting success (30.7%; measured directly through monitoring of nests or presence of fledglings within the territory) was lower than necessary for a source population, but average when compared to other parts of the range. We recommend further inquiry into the fate of the Indiana population, as well as studies to assess reproductive rates and suitable breeding habitats that may exist elsewhere in the Cerulean Warbler's range.