New research using data loggers tagged to thirteen common swifts has revealed that these birds were capable of remaining airborne for months at a time.
The researchers found that some of the birds made a few brief night landings in winter but remained airborne for 99% of the time. Three birds didn’t touch down once in the entire ten months….“Common swifts have evolved to be very efficient flyers, with streamlined body shapes and long and narrow wings, generating lift force at low cost,” says Anders Hedenström, a study co-author and a biologist at Lund University in Sweden. The birds even eat while airborne, snatching flying termites, ballooning spiders and other aerial insects for in-flight meals.
Hedenström says that common swifts have adapted to a low-energy lifestyle, but his team does not yet know whether the birds sleep while aloft. “Most animals suffer dramatically from far less sleep loss,” says Niels Rattenborg, a neurobiologist at Max Planck Institute for Ornithology in Seewiesen, Germany. “But these birds seem to have found a trick through evolution that allows them to get by on far less sleep.”