How can I keep bugs out of the MacBook Pro's hinge vent?
Hmmm....I have a pc and it's bug free.



[non-troll answer]

Ok, ok....you might try flushing the vent openings with canned air while the computer is off.  Turn the can upside down so that you can actually get that super cold dangerous liquid in there.  Maybe there's some kind of scent that's drawing them in (is it the same species?).