So, question first: Do bats eat wasps? Technically, yes. Practically, no, they don’t, because wasps don’t fly at night, really, at all. The European Hornet, Vespa crabro, will occasionally come to a porch light, as will an occasional Bald-faced Hornet (Dolichovespula maculata). They seem to hunt there. Both are aggressive insect-hunting wasps (they feed the muscle tissue to their young).

My wife is perfectly okay with wasps being a Force for Good in nature. She doesn’t care for the way I’m willing to coddle them even when they come into the house.

Just for the record, even though honeybees get all the good press because, you know, pollination, and honey, wasps are actually much less dangerous. While they are capable of pursuing a person much farther than a honeybee can, and much faster, they are much less likely to sting than bees, and highly unlikely to gang-sting in an effort to kill the intruder. Bees have evolved a sting to the death response along with plentiful and effective aggregation pheremone, which means it is possible to be stung to death for bumping into a hive. Granted, most bee sting deaths are allergy related, but a sizable fraction are just because a person was in the wrong place at the wrong time. Somewhere between 100 and 150 deaths each year from this. The good news is that bees won’t chase you very far. Run away full out (don’t swat at them, it doesn’t work and it slows you down) until you can’t hear them buzzing around you. Very few wasp related deaths, comparatively. The last numbers I saw were in the neighborhood of 5–6 per year. Fewer than sharks.

Those wasps that swoop around you in your yard all menacing and vicious-looking? The really big ones? Those are almost always males. They charge of toward anything that moves in case it might be female. It’s worse if there’s perfume involved. But they don’t have stingers. Large female wasps are shy and solitary, much more interested in taking care of the kids (so to speak).