I have these little blackish bees in the outside of the house, I guess maybe
6mm long or so. I think they must be pretty common because I've seen them so
many places before. They get into the little squarish holes between panels
in the wood siding. They seem indifferent to my presence & pretty much just
go about their business. Do the bees make the holes themselves or do they
just exploit the flaws? Seems like a bee would chew a rounder shape. Are
they very damaging?