Alligator snappers are stealth hunters for a few years. They "lure" with open mouths, waiting for fish (guppies, then rosey reds, then full sized minnows) to come by and try to eat the wormlike part of their tongues, then, BAM! the bear trap slams shut on the hapless prey. My understanding is that they will then take inert prey, like chicken parts (especially necks) or worms, only after they are a few years old. My 3 1/2 year old still won't take anything except fish that swim by, but he's started to forage for dead stuff, worms,chicken when he has no live prey. The taking of food other than fish on the fly, is a recent development. With the lights out, they start to go for nonmoving foods at about 3-4 years old. Before that, if it doesn't come to them while "angling", it doesn't get eaten.