A team of scientists in Sweden has proved that these birds fly for tremendously long periods of time. They affixed data loggers onto a total of 19 of the master fliers in 2013 and 2014, and recaptured the birds months later. Researchers and ornithologists found that the birds can spend almost their entire 10-month nonbreeding period on the wing.
The data loggers gathered information on acceleration and flight activity, and those installed in 2014 also included light trackers for geo-location.
The results were astonishing. For example, according to research published in Current Biology, one of the birds stopped for just four nights in February in 2014 — and the next year it stopped for only two hours. Other birds stopped for longer periods of time. But “even when swifts settle to roost,” the researchers say, “the amount of time not flying is very small,” , according to a report published in National Geographic.
The birds are known to travel from Europe to sub-Saharan Africa — but they apparently don’t touch down there. Researchers say they have never found roosting sites in sub-Saharan Africa.
The birds’ shape contributes to this finding; their “wings are too long and their legs are too short to take off from a flat surface,” it is reported.