Long-distance dispersal patterns and carry-over effects in the Cerulean Warbler (Setophaga cerulea) in southern Indiana

Access to thesis permanently restricted to Ball State community only.The Cerulean Warbler (Setophaga cerulea) is a migratory bird that breeds in mature deciduous forests of eastern North America and overwinters in northern South America. The species has declined precipitously since the mid-1900s, and is currently Endangered in the state of Indiana. Causes of Cerulean Warbler decline are thought to be loss of habitat on the breeding grounds; however, very little research has been conducted on this species’ wintering ecology. The first objective of this study was to investigate long-distance dispersal patterns of Cerulean Warblers in a population breeding in southern Indiana. The second objective was to determine whether habitat quality occupied on the wintering grounds may impact the body condition and reproductive success of Cerulean Warblers during the following breeding season. I used stable isotope analysis of Cerulean Warbler tissue sampled on the breeding grounds to investigate these two objectives. I discovered a high rate of long-distance dispersal in the southern Indiana population, and that the majority of these immigrants appeared to originate from regions south of Indiana. I did not find differences in dispersal rates between juvenile and adult Cerulean Warblers; however, I discovered that female Cerulean Warblers may disperse more frequently compared to males. Furthermore, immigration did not significantly impact nest success. I used stablecarbon isotope values of claw tips sampled on the breeding grounds to infer wintering habitat quality, and found that isotope values increased rapidly within the first 7 weeks of the breeding season. This finding indicates that Cerulean Warbler claw tips may have a higher isotopic turnover rate than previously anticipated, and that this tissue may not accurately represent material that was solely grown on the non-breeding grounds. These studies contribute to our current limited knowledge of Cerulean Warbler full annual cycle ecology, and have important implications for the management of this declining species.Thesis (M.S.