Why is the coast of the Gulf of Mexico important for migratory birds?

Habitats along the U.S. coast of the Gulf of Mexico provide critical resources for North America's migratory birds. The majority of the birds that breed in North America travel across the Gulf of Mexico every spring and fall as they migrate between temperate breeding grounds in North America and wintering grounds in the southern US, Caribbean, and Central and South America. During these twice annual journeys, migratory birds congregate in the barrier islands, beaches, marshes, forests and airspace habitats along the U.S. coast of the Gulf of Mexico from southern Texas to the Florida Keys. These coastal habitats comprise some of the most important wintering and resting and refueling areas for North America's migratory birds.

photo by Emily Cohen

In general, almost 40% of the birds in North America are declining and 75% of all the birds in the states and Canada are migratory. Many if not most of these use the Gulf coast for both fall and spring migration. It is possible that the loss or degradation of important gulf coast habitat could play a role in limiting migratory bird populations across North America. This project is central to The Smithsonian Migratory Bird Center's mission to determine why migratory bird populations are declining so rapidly. We know that Gulf coast habitats provide critical habitat for North America's migratory birds yet we haven't figured out which areas support the highest concentrations and of what species, how birds are doing in those areas, or the potential threats and vulnerabilities of habitats in those areas. This knowledge will help prioritize conservation efforts to protect these remarkable species.

Mapping migrants with weather radar and eBird

We know that Gulf coast habitats provide critical stopover areas for North America's migratory birds yet we haven't figured out which areas specifically support the highest concentrations and of what species. The first step to understanding how the gulf coast's habitats influence populations of North America's migratory birds is to map out the regional distributions, abundance, and habitat affiliations of these species. With support from The Gulf Coast Conservation Grants Program we will be mapping spring and fall migrations around the Gulf of Mexico coast using weather radar and citizen-collected (eBird) data. Resulting maps will be used by conservation planners and policymakers as decision support tools to develop Gulf-wide conservation priorities for North America's migratory birds. This work is in collaboration with Jeff Buler at University of Delaware and Andrew Farnsworth at the Cornell Lab of Ornithology.

Migration banding for passage timing and condition

We have been banding migrants in some of the first resting and refueling habitat for northward migrants after hundreds of miles of non-stop flight across the Gulf of Mexico, including The Nature Conservancy's Clive Runnells Family Mad Island Marsh Preserve (Mad Island) in Matagorda County, Texas and Powderhorn Ranch in Calhoun County, Texas. This work is in collaboration with Frank Moore at The University of Southern Mississippi.

Catching hitchhikers crossing the Gulf

Migrants are also vectors of biodiversity. Our recent work suggests millions of exotic ticks are likely hitching rides on birds across the Gulf of Mexico each year from Central and South America and potentially carrying harmful pathogens with them. Yet, the frequency, origin and destination of ongoing Neotropical tick invasions into the United States have not been studied, in large part due to our inability to track the movement of birds that serve as their carriers. We are studying the movement of ticks and tick-borne pathogens on migratory birds after the cross the Gulf of Mexico into the United States. This work is in collaboration with Sarah Hamer at the College of Veterinary Medicine at Texas A&M University. This year we started sampling the feathers and feet of migrants to see if they are carrying moss spores! We are doing this work with Matthew Chmielewski, a PhD Candidate at Portland State University in the Biology Department.

Raising awareness for the grand phenomenon of migration

In the course of conducting this research, we hope to increase awareness of the importance of the northern coast of the Gulf of Mexico to bird populations, and increase awareness of the phenomenon of bird migration, ecology, and conservation. We write an annual spring migration blog (see below) and have hosted over 500 students from local schools at our banding sites. See our short film about our outreach at Mad Island (Migratory Connectivity Project: Songbirds Return).

SMBC Investigators:

Expedition Blogs

Banding Data

This data is not intended for publication. These numbers include unbanded birds, and birds recaptured from previous seasons. For more information please contact Emily Cohen and Pete Marra.

Download banding data


The weather radar and eBird projects are receiving funding from Gulf Power and Southern Company through their Gulf Coast Conservation partnership with National Fish and Wildlife Foundation. The banding and outreach are made possible with the support of ConocoPhillips, Helen DuBois, The Trull Foundation, and The Nature Conservancy.