Changes in Avian Capture Rate and Migration Phenology Across 37 Years at a Coastal Barrier Island in Georgia

Migration is one of the riskiest periods in a bird’s yearly cycle, and monitoring migratory trends helps us understand how birds are impacted by the changing world. Here, I present an analysis of 37 years of fall bird banding data collected at the Jekyll Island Banding Station in Georgia. Capture rates of Neotropical migrants on Jekyll have declined 50-90% in many common species, and the mean ordinal passage date of Gray Catbird and Western Palm Warbler have shifted 8 days later. Landcover analysis of the island yielded non-significant results; therefore, human-caused habitat change on breeding and wintering grounds are likely the primary drivers of lowered capture rates. Rising temperatures on breeding grounds are extending growing seasons and are suspected to be a primary driver influencing migration phenology trends. This research contributes to a growing body of work on Neotropical migrants and presents the first analysis of this dataset.