It weighs just half an ounce and its natural home is a tree. But tiny songbird the blackpoll warbler routinely undertakes non-stop flights of up to 1,700 miles across open ocean, scientists have confirmed. The heroic journeys are 'on the brink of impossibility', according to one of the researchers who attached tracking devices to 40 birds. Long journey: The blackpoll warbler routinely undertakes flights of up to 1,700 miles, flying without stopping to rest, eat or drink across the Atlantic . Experts had long wondered about tantalising clues that suggested the warbler was capable of epic migrations between North and South America. Now they have proof that it really does fly without stopping to rest, eat or drink across the Atlantic. Unlike other migratory songbirds travelling south for the winter, the warbler ignores the safe option of hugging the coastline through Mexico and Central America. Instead it risks death by flying hundreds of miles from land even though it cannot land on water and live. Nice flight: A blackpoll warbler wearing a miniature tracking device . US scientists were astonished when they analysed data from some of the birds they tracked from New England and Canada to the Caribbean, Venezuela and Colombia. Dr Bill DeLuca, from the University of Massachusetts at Amherst, said: 'It was pretty thrilling to get the return birds back, because their migratory feat in itself is on the brink of impossibility. 'When we accessed the locators, we saw the blackpolls' journey was indeed directly over the Atlantic. The distances travelled ranged from 1,410 to 1,721 miles.' He added: 'For small songbirds, we are only just now beginning to understand the migratory routes that connect temperate breeding grounds to tropical wintering areas. 'We're really excited to report that this is one of the longest non-stop over-water flights ever recorded for a songbird, and finally confirms what has long been believed to be one of the most extraordinary migratory feats on the planet.' For the study, published in the Royal Society journal Biology Letters, the scientists captured 20 birds in Vermont and another 20 in Nova Scotia and fitted them with geolocator packs. The devices, each about the size of a 5p piece, were attached using leg harnesses, much like a rucksack. Too small to house GPS receivers, they operated by means of 'solar geolocation' - a method used for centuries by mariners and explorers. It is based on the fact that day length varies with latitude and the time of solar noon - when the sun is at its highest point in the sky - varies with longitude.
Blackpoll warbler undertakes non-stop flights of up to 1,700 miles . Flies without stopping to rest, eat or drink across the Atlantic . US scientists tracked birds from New England to the Caribbean .