Called hornworm caterpillars or other names, the green horned caterpillars are awful. They eat our plants!
They start out really small, and they come out at night to feed. So during the heat of the day they are hidden. We learned that a black light is effective for looking for them at night. You have to squish them completely. A black light headlamp is the best tool because then you have two hands free: one to hold the branch or leaf at the angle you need and one to pick off the caterpillar.
The caterpillar seen in these photos has gotten huge because a lot of time had passed before we caught it. Usually they don’t get this big because we catch all of them when they are smaller, the size of inchworms or smaller. Usually they like tomatoes, so we didn’t think to check the bell peppers!