I just did a quick google search and found a number of references to torpor
in swallows. I didn't investigate much beyond that but it makes sense that
early arriving or late departing insectivores, such as swallows, may use
this strategy during periods of inclement weather (which can occur at
northern lattitudes even throughout summer). Or maybe it has more to do with
the fact they rely mostly on flying insects. It does not neccesarily follow
that hibernation also occurs but who knows - it would be hard to prove the
negative.

thanks, Charles.

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Charles E. Swift
charless at moscow.com
Moscow, ID, USA
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