A new study by Swedish scientists shows that common swifts are capable of flying for 10 months without once touching land.

These birds likely save energy during the day by gliding in upward currents of warm air. But they also ascend to high altitudes each day at dawn and dusk, reported Current Biology journal.

The researchers at Lund University in Sweden attached data loggers to 19 common swifts, to track them when they leave their breeding site in August for a migration to the Central African rainforests via West Africa.

And they found out that three of these birds never landed at all, whereas the rest interrupted their flight only in emergency conditions, such as adverse weather.