Researchers have tracked the migratory paths of songbirds for the first time, using small data-gathering “backpacks,” the Washington Post reports. The avian wanderers, who are so small they cannot be tagged with transmitters, move about 3 times as a fast as previously thought. The recovered data shows that birds traveling between the US and Brazil can make up to 311 miles in a day. They're usually faster heading south, possibly in a race to get the best breeding spots.
One specimen, a purple martin, covered 4,650 miles in just 13 days; another, a wood thrush, took a leisurely route north—2,852 miles in 29 days. In the latter case, the bird opted not to attempt a nonstop flight over the Gulf of Mexico, possibly because degraded wintering grounds in South America had left it undernourished, the Post notes. Scientists say the data will be an invaluable tool and could help them better protect the songbirds.