Swift body temperature

[Danny McG]

Is this correct? Can swifts do this?

Extract from Tinker, Tailor, Soldier, Spy:-

No,” said Smiley. He was quite impassive.

“George is like a swift,” Ann had once told Haydon in his hearing.
“He cuts down his body temperature till it’s the same as the environment. Then he doesn’t lose energy adjusting.”

 

[HareBrain]

Young swifts in the nest can do it. They go into a kind of short-term hibernation torpor if food is scarce.

I don't think this is true of adults, who in any case would be generating quite a bit of heat from beating their wings.

 

[Alex The G and T]

Laden or unladen?