At the Peggy Notebaert Nature Museum, volunteers feed different groups of animals on different days as part of public interpretative programs (PIP). Recently, to keep things fresh for volunteers and visitors, the schedule was shuffled, and now aquatic animals are fed on Monday, fish on Tuesday, Blanding’s turtles on Wednesday, water snakes on Thursday, box turtles on Friday, and endangered turtles on Saturday.
Leopard Frog wearing his lunch
And on Sunday, frog and toad feeding takes place in the Look-in-Lab, where the volunteers offer crickets by hand or tweezers to the anurans in tanks along the viewing window. (Frogs and toads belong to the order of amphibians called “anura” so collectively are referred to as “anurans.”) The session is entertaining for visitors; they laugh when a volunteer involuntarily jerks her hand back as the critter grabs mouth first for its meal (you tell yourself not to, but it is a reflex that is hard to overcome), and they applaud when the critter gets the cricket. To make the feeding educational as well, other volunteers stand on the public side of the window to provide visitors information about frog and toad diets and habits.
Frogs and toads are usually sit-and-wait predators, relying on camouflage to hide their motionless bodies until an unsuspecting potential meal moves within reach of a lunge and “lingual flip:” the tongue flips out and slaps on the target and then flips back with the prey stuck on. This capture technique is made possible by a tongue that is attached to the front of the jaw and free at the back (unlike those of humans and other animals) and by a gummy mucous exuded at the instant of contact. Thus, the anuran tongue does not shoot out like the tongue of a chameleon or a cartoon frog. The whole action takes less than 15/100ths of a second, faster than our eyes can follow. Below is a cool, slow motion video of a leopard frog flipping up a waxworm with its tongue.
Frogs and toads have teeth but only along their upper jaws. Their teeth are weak and are not used to chew or tear, but to hold prey before it is gulped down whole. Their eyes help anurans swallow their meals; an emphatic blink presses their eyeballs through holes in the skull, pushing food down the throat.
Most frogs and toads eat insects, spiders, worms, larvae, and slugs, although larger species may also eat small birds, reptiles, or amphibians. Every two to three weeks, the Museum orders 2,500 crickets (1,000 small, 1,000 medium, and 500 large) -- between 65,000 and 44,000 a year. They are fed not only to the frogs and toads, but also to the Museum’s salamanders, some turtles, aquatic insects, and spiders.
The Museum has 12 species of anurans, all also found wild in Illinois: Fowler’s toad, American toad, pickerel frog, green frog, leopard frog, plains leopard frog, chorus frog, cricket frog, wood frog, green tree frog, Cope’s tree frog, and gray tree frog.
PIP and Animal Care Volunteer