Hummingbirds are not birds of prey at all. They are just flower suckers and nothing more. I really don't know what blue birds eat. I think they are seed eaters. Blue Jays will eat many things. I've seen them eating small lizards. I bet they'd grab a frog as well. I don't know whether they would go after any little mammals. Shrikes will go after mice, lizards, and about anything else. Shrikes are known for attacking some animals that are actually bigger than they are.
WFTR
Bill