Snapping turtles have a rather interesting evolutionary development known as "Lingual Luring". The snapping turtle's tongue has evolved into a "worm like" structure it is able to wiggle like a worm.
This development allows the snapper to lay motionless in water with its mouth open while wiggling its tongue. Unsuspecting fish, no matter their intelligence quotient, are lured by the tongue and when they take the bait (tongue) the snapping turtle closes its jaw.
Snapping turtles are rather efficient at eating live, healthy fish.
