by Dave Miller » Sun Aug 29, 2010 12:17 am
It is very common for bats to roost in patio umbrellas, because folded umbrellas provide roosting spaces that are very similar to their natural roosts, which is under the bark of tall, dead trees or in tree cavities and rock crevices.
The bat should be leaving the umbrella every night to feed, then comes back to the umbrella before sunrise to sleep during the day.
You don't say where you live, but if you live someplace with cool or cold winters, in the fall the bat will leave your yard for someplace to hibernate for the winter, probably a cave or a mine. If possible, just leave the umbrella up until you notice that the bat is gone for the winter. But if you do need to put away your umbrella, just put it away at night when the bat is out feeding. The bat will find someplace else to roost (though it obviously likes your umbrella!).