No, for the US, only the brightly colored fuzzy ones are venomous, black brown and white are usually safe except for the one that looks like it's made out of a wig. And then monarchs but I hope to God you're not planning on using endangered species as feeders. Tent moths and army worms are environmentally detrimental, plentiful, and make good fish food. You'll only really start getting into actually poisonous caterpillars if you find the caterpillars of exotic butterflies in the rainforests of south america or whatever.