By: Sabrina Cobb
On March 4th, Alabama Audubon Coastal Biologists and Science & Conservation Director met our boat captain at the Bayou La Batre boat launch on a quest to find American oystercatchers on Coffee Island. Prior to embarking the vessel, Coastal Biologists scoped the marsh restoration area for a known oystercatcher pair that has been frequently seen loafing on the rocks lining the channel. The weather was perfect, mostly clear, temperature in the 50’s, and the Mississippi Sound calm beneath us.
Coffee Island (or Isle aux Herbes) is historically known to host breeding pairs of American oystercatcher. As we approached the island, all eyes were monitoring the oyster shell lined coast for any sign of activity. It did not take long for us to locate two pairs, one on the northern part of the shoreline and the other a bit south of them. Once we found a safe place to land the boat, we disembarked and started cautiously walking in the direction of the first pair. We found a spot that was close enough for our sound equipment to be heard by the birds but far enough away to decrease flushing them. Our method of approach for capturing these adult birds was to secure three “noose mats” in a triangular position on the ground and then place a decoy in the center along side a speaker playing the species’ call. This works if the birds are displaying territorial or breeding behavior as the call will spark interest in the pair. Unfortunately, when we finished setting up and started the calls, the birds became spooked and flew across a section of marsh making it difficult to attract them.
We decided to move carefully further down the shore periodically monitoring the behavior of the second pair. Once we found another ideal location, we set up our gear once more and then retreated down the shore to monitor and wait for activity. At first the birds were unresponsive so our Science & Conservation Director, Lianne, started to slowly work her way around to their location. This slow intrusion helped coerce the birds in the direction of the decoy. As soon as they were close enough to hear the calls and see the decoy the birds started immediately displaying territorial behavior. The pair moved closer and closer to the decoy bowing and raising their heads simultaneously as they called back. It was quite the sight to observe. As the pair became more defensive, they were walking on the noose mats and began to push at the fake bird. With all the commotion one of the birds was successfully captured, so we all quickly ran over to start the banding process.
The first thing we did was designate someone to hold the bird, someone to band and take measurements, and someone to record the data. For American oystercatchers we put a federal metal band on their right lower leg and a dark blue band with white letters on both upper legs. This bird was banded with the code “JT”. After the bands were secured, we collected measurements on the bill, wing cord, tarsus, and weight. This is the first adult oystercatcher banded for Alabama! We have been banding these year-round residents to further our knowledge on their breeding success, loafing and foraging habitat preferences, and movements. Here along the Alabama coast, we have close to ten individuals that use habitat on the nearshore islands and Dauphin Island.
How to Report a Banded Bird
If you see a banded oystercatchers (or any banded bird along the coast) you can email us with the details of your sighting. You can also submit banded bird sightings to: the American Oystercatcher Working Group (only for oystercatchers), the Bird Banding Laboratory (for any bird that has a silver/metal federal band), or here if it is a shorebird with only color bands, and no silver/metal federal band.