You may find night-fliers hanging about in them (8)
I believe the answer is:
belfries
'hanging about in them' is the definition.
I can't tell whether this defines the answer.
'you may find night-fliers' is the wordplay.
I cannot really see how this works, but
an anagram of 'fliers' is 'lfries' which is present in the answer.
The remaining letters 'be' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Another definition for belfries that I've seen is " Bell towers as on churches".)