In many ways, cockroaches are ideal food for insectivorous reptiles; they lack defensive weapons like stingers or teeth, many species are unable to fly and some communal species are locally abundant. Most insectivorous reptiles -- including crocodilians, turtles, snakes, lizards and tuataras -- consume cockroaches when the opportunity presents itself.
Though it would take thousands of cockroaches to fill the belly of an adult alligator or crocodile, insects are important prey for most young crocodilians. While roaches are not aquatic, they often forage along the plants and land surfaces near bodies of water. Hungry young crocodiles, alligators and caimans lurk in the shallow portions of ponds and wetlands waiting to spot a big insect like a cockroach. The teeth of young crocodiles are sharper than those of the adults, so that they are better equipped to catch insects and slippery prey.
Many terrestrial and semi-terrestrial turtles eagerly eat cockroaches. Eastern box turtles (Terrapene carolina) frequently forage along the margins of logs and rocks, trying to uncover insects and worms. If they manage to find a cockroach, they quickly snap it up -- using their front legs to rip it into smaller pieces if necessary. Aquatic turtles also consume cockroaches if the insects accidentally wind up in the water.
While the majority of snakes predate on vertebrates, some species consume insects. Copperheads (Agkistrodon contortrix) are well-known for catching cicadas, and scientists have documented them and their relatives the cottonmouths (Agkistrodon piscivorous) eating cockroaches as well. Few studies specifically detail the exact species consumed, but many have documented a variety of snake species eating insects. The rough green snake (Opheodrys aestivus) is an insect specialist, pursuing flying and crawling insects in shrubs and trees. Small, invertebrate-eating species of the leaf litter -- like brown snakes (Storeria dekayi) -- likely consume small roaches from time to time.
Virtually all insectivorous lizards consume cockroaches when they find them. Cockroaches often live in caves, tree hollows and deep animal burrows. Lizards that live or forage in these areas are the ones most likely to consume cockroaches. Cave-dwelling species like leopard geckos (Eublepharis macularius) consume many different insect species including roaches. Some tropical roach species exceed 4 inches in length; monitor lizards (Varanus sp.), spiny-tailed iguanas (Ctenosaurus sp.), basilisks (Basiliscus sp.) and other medium to large lizards benefit greatly from eating these large roaches. Scientists have also documented the limbless glass lizards (Ophiodes striatus) consuming roaches.
The tuatara (Sphenodon punctatum) superficially resembles a lizard, but it has many important behavioral, anatomical and evolutionary differences. These unusual reptiles are nocturnal, and chiefly consume large prey such as rodents, ground-nesting birds and their eggs. However, insects are also important food items, especially for young tuataras. As roaches are nocturnal and often inhabit the same burrow systems that tuataras do, they may find themselves trying to escape from the lizard-like reptiles.
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- Turtles; Charles Fergus