Picnic(1983)

You call this a picnic!!?? Just when you are ready to sit down and eat your juicy cheeseburgers, a swarm of nasty bugs comes along intent on beating you to the munch. They start eating and you start swatting, and the battle has begun. It's a good thing you brought along your bug zapping trap. Now, swat those critters into the trap, and just maybe there will be something left for you to eat for lunch.