Graduate Exit Seminar - Ivy Ciaburri

Plan to join Ivy Ciaburri's graduate exit seminar on April 25, 2024, at 12:00 pm in Heffner Wetland Building 128 or via Zoom. Ivy will present, "Feather quality as an indicator of breeding to nonbreeding carry-over effects in the American Redstart."

Abstract: American Redstarts (Setophaga ruticilla) have provided invaluable insights into the importance of studying full-annual cycle biology of migratory birds. That said, almost all this research has examined the influence of nonbreeding on breeding season events and we know little about how breeding-ground environmental conditions affect subsequent phases of the annual cycle despite expected climatic change on temperate breeding habitats. Here, I explore relationships between environmental conditions on the breeding grounds and feather quality, an indicator of an individual’s health at the time of molt. Using a 20-year collection of tail feathers (3rd rectrix) sampled from a population of nonbreeding redstarts in southwest Jamaica, I measured each feather’s carotenoid content via spectrometry, feather density, and growth rate to evaluate feather color and structural quality. I leveraged the fact that our study population breeds in the Upper Midwest to derive annual estimates of environmental conditions (NDVI and precipitation) on the breeding grounds via remote sensing. I then investigate the relationships between environmental conditions on the breeding grounds and individual feather quality and evaluate potential breeding to nonbreeding carry-over effects by relating individual feather quality to spring migration departure. This expands upon previous research by incorporating more direct indicators of food availability, structural feather quality, and the known breeding area of Jamaican redstarts.

Advisor: Dr. Christopher Tonra