The coastline of the northern Gulf of Mexico (NGOM) represents important non-breeding habitats for 28 species of migratory shorebirds. As processes of climate change accelerate, these habitats are expected to experience dramatic land loss. In addition, the NGOM has experienced several natural and human mediated disasters over the last decade, including Hurricane Katrina and the Deepwater Horizon Oil spill (DWH). Predicting the impacts of these events requires an understanding of the interactions between shorebirds and their habitats. However, the migration ecology of shorebirds on the NGOM has not been well studied. To better understand the effects of the DWH and the importance of NGOM habitats to the migration ecology of shorebirds I carried out two related studies. First, I investigated the potential for long term, large-scale effects of oil exposure to migratory shorebirds through both a literature review, and by investigating the exposure to DWH oil in seven species of shorebirds that winter or stopover along the NGOM. I found that through migratory carry-over effects, oil spills and other environmental disasters, have the potential to impact ecosystems far from the event. Exposure results suggest as many as 1 million shorebirds were impacted by direct exposure to oil, and many more may have been negatively affected by disturbance from cleanup activities in oiled habitats. Second, I investigated the migration ecology of three near-arctic breeding species of shorebirds (Semipalmated sandpipers (Calidris semipalmatus), Western Sandpiper (C. mauri) and Dunlin (C. alpina), by measuring within- and among-species variation in habitat use, stopover duration, and refueling rates, as measured by plasma metabolites, across 3 habitat types. I found that among species, shorebirds vary in their migration ecology according to the distance to the next stopover site, suggesting NGOM habitats may be particularly important to longer-distance "jump" migrants (Dunlin). I also found that while shorebirds are found across all habitat types sampled, the back bay habitats of barrier islands provided a higher quality habitat (as evidenced by higher prey biomass, and a higher refueling rate) than traditional coastal mudflats or remnant wetlands, highlighting the importance of considering shorebird ecology in barrier island restoration plans.
