If this were April, I don't think
I would believe it:
The common swift is a bird shaped by and for the air. In flight it looks like a crescent moon, with just a hint of head and a tail that, when spread, echoes the curve of its wings.
Scientists have now confirmed that it can spend up to 10 months in the air without landing. Only when it makes a nest does it need to come to Earth. It can even mate during flight.
Anders Hedenström, a biologist at the University of Lund, and his colleagues determined how much time swifts spend in the air by capturing them in southern Sweden, where they summer and nest, and attaching micro data loggers.
Some swifts rest occasionally, but on the whole, when they are not nesting, they spend 99 percent of their time in the air. They sleep in the air, but plenty of birds do that. I don't know of any other that can spend months straight in the air. Astonishing.
I presume if your primary food source is itself airborne, and you live in an environment with plenty of wind and thermals for nearly effortless gliding, there really isn't much reason to land if your physiology can even manage to sleep in mid flight.
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