Why bats don’t fly during the day

I was doing my stoutness exercises at my local oval (Hughes, ACT) this
morning and, while it was still dark 6-8 small insectivorous bats were
circling around feeding. (Don’t know what sp but they were all dark and the
body length was 5-6 cms).

As it got lighter they all disappeared except one which was obviously
trying to get some last minute feeding in. A Magpie saw it and swooped at
it and the bat made for the trees at the other side of the Oval (about 250
m away). The Magpie took off after it and easily caught up with it, but
when it did the bat simply circled the Magpie, which was spinning, trying
not to lose height and squawking in frustration. When the Magpie was dizzy
the bat set off again, but same thing thing happened another two times
before it made the safety of the trees.

Guess that trick wouldn’t have worked if it had been pursued by a
Sparrowhawk or Hobby.

—
John Leonard
Canberra