A frog's diet depends on its size, with smaller frogs dining on flies while larger frogs eat worms and grasshoppers. Very large frogs have been known to eat small snakes, mice, baby turtles and other frogs. Frogs do not like carrion, sometimes starving to death rather than scavenging.
Frogs eat insects, most of which are available either live or dead in pet shops. If crickets are unavailable, they can eat spiders, grasshoppers and beetles. If catching insects for consumption, owners should make sure they have not been sprayed with an insecticide. The frequency of meals depends on their size; small frogs need to be fed once a day while larger species can be fed every other day or less.
Frogs are sensitive to movements and prefer to eat live prey, even when kept as pets. They hunt with their sticky tongue. Frogs are unique in that their tongue is attached to the front of their mouth rather than the back, allowing them to shoot their tongue out rapidly to ensnare prey. Some species rely on camouflage to stalk their prey and hide, preferring to sit motionless until an insect comes near.
Very few species of frogs have teeth; most prefer to swallow their food whole. Those with teeth have them on their upper jaws, and they are used only to immobilize prey.