A male Red-necked Phalarope wearing a light-level geolocator has upended conventional wisdom about its species and revealed one of the world’s great bird migrations.
In spring 2012, researchers placed geolocators on 10 phalaropes on one of Scotland’s Shetland islands. A year later, they recaptured the bird pictured above and retrieved its tracking device.
It revealed that the phalarope had made an epic 16,000-mile round-trip journey: From Fetlar, located 155 miles northeast of the mainland, it crossed the Atlantic via Iceland and Greenland, headed south down the eastern coast of North America, flew over the Caribbean and Central America, and ended up off the coast of Ecuador and Peru. Then, after wintering in the Pacific, it reversed its route and returned to Fetlar.
Red-necked Phalarope breeds in arctic and sub-arctic wetlands in Alaska, Canada, Greenland, Russia, Scandinavia, and Iceland, and it winters at sea, primarily off the Pacific coast of South America, in Indonesia, and in the Arabian Sea.
Scottish islands host the only remaining breeding populations in the United Kingdom: 15 to 50 nesting males each year. Ornithologists had assumed that Scotland’s birds wintered in the Arabian Sea, but the bird from Fetlar threw a wrench into those assumptions.
The tracked phalarope “isn’t part of an offshoot population from Scandinavia,” says Malcolm Smith of the Royal Society for the Protection of Birds. “Our Shetland population is actually an offshoot of a North American population. To think this bird, which is smaller than a starling, can undertake such an arduous journey and return safely to Shetland is truly extraordinary.”
Only a handful of species, including Sooty Shearwater, Arctic Tern, Red Knot, Pectoral Sandpiper, and Northern Wheatear, cover longer distances each year.
Smith plans to fit 10 more phalaropes with geolocators this year to determine if they follow the same route.
A version of this article appeared in “Birding Briefs” in the April 2014 issue of BirdWatching. Subscribe.