A tiny songbird that summers in the forests of northern North America has been tracked on a 1,700-mile, over-the-ocean journey from the northeastern US and eastern Canada to the Caribbean as part of its winter migration to South America. Scientists had long suspected that the blackpoll warbler had made its journey to the Caribbean over the ocean, but the study that began in the summer of 2013 when scientists attached tracking devices to the birds was the first time that the flight has been proven, according to results published in the journal Biology Letters. "It is such a spectacular, astounding feat that this half-an-ounce bird can make what is obviously a perilous, highly risky journey over the open ocean," says co-author Chris Rimmer of the Vermont Center for Ecostudies.
In the summer of 2013, scientists tagged 19 blackpolls on Vermont's Mount Mansfield and 18 in two locations in Nova Scotia. Of those, three were recaptured in Vermont with the tracking device attached and two in Nova Scotia. Four of those warblers had departed between Sept. 25 and Oct. 21 and flown directly to the islands of Hispaniola or Puerto Rico in flights ranging from 49 to 73 hours; a fifth bird departed Cape Hatteras, NC, and flew nearly 1,000 miles before landing in the Turks and Caicos and continuing on to South America. On their return journeys north, the birds flew along the coast. Knowing how the blackpoll warblers migrate helps scientists know more about the implications of changing climate and why their numbers may be declining, says a migration biologist.