Do yellow jackets swarm

Technically, any animal/insect with a mouth can bite. However, only some bites are poisonous. Yellow jackets can bite you but they normally wouldn't and it wouldn't be poisonous. Yellow jackets transfer venom into the body via stingers. So to harm you they would have to sting you. [Yellow jackets can only sting once, then they die] A yellow jacket could bite you because they have mandibles, sort of like teeth (you could look them up on google).

So to sum it up they could bite you, but it wouldn't harm you.