Before Manomet researchers left Coats Island in Hudson Bay this summer, the team examined a nearby site that was recently discovered as a possible staging location for Whimbrels during their migration from the Arctic to South America.
Manomet’s Brad Winn has worked with the Georgia Department of Natural Resources and the Center for Conservation Biology over the past few years to put satellite transmitters on Whimbrels.
Winn and the partner organizations observed that one of the birds stopped on Coats Island in two different years after nesting in Canada’s Northwest Territories. The bird spent about a month on the island before undertaking a 4,000-mile journey over the Atlantic Ocean to the north coast of Brazil.
“We knew there was something [at Coats], some kind of important stopover site, so we wanted to take a look while we were already in the area,” Winn said.
The team was unfortunately unable to land at the site, where Winn said they had wanted to do invertebrate sampling to better understand the Whimbrels’ possible diet there. The team’s Twin Otter aircraft was able to circle over the area and the team returned with plenty of photos and a good idea of the site’s ecology.
“There was plenty of rich coastal wetland and we saw many different shorebird species. Although we didn’t see any Whimbrels, we expected that since it was a little too early for their migrations,” Winn said.
Whimbrel populations have been in decline, and the birds are hunted in South and Central America. Their migratory pathways are also vulnerable to human impositions, so understanding the migrations is key to their conservation.
Manomet and the Georgia Department of Natural Resources have put eight transmitters on Whimbrels while the Center for Conservation Biology has placed another 20. The transmitters are powered by solar panels and are designed to last at least two years.
The tracking efforts have revealed the full extent of a loop migration route that was previously only partially known to researchers. During the summer, the birds breed in the Northwest Territories of Canada before heading to the eastern coast of Canada (including places like Coats Island) where they prepare to make the long trip to the northeast coast of South America. They spend the winter there before traveling to staging areas in the Gulf of Mexico and Georgia, and then back up to their breeding grounds in Canada to complete the migration.
The species’ staging areas, where the birds stop for several weeks to prepare for long, continuous journeys, are critical to their survival. The stopover points at places like Coats Island and in the Gulf of Mexico need to be protected and monitored, as disturbances in these areas can have effects in ecosystems thousands of miles away, according to Winn.
The stop at Coats Island is a part of a larger project that has tracked Whimbrels since 2008 and involves Manomet, the Center for Conservation Biology, the Canadian Wildlife Service, The Nature Conservancy, the U.S. Fish and Wildlife Service, the Georgia Department of Natural Resources and the Virginia Coastal Zone Management Program.
– Gordon Bailey