Boas: Boidae

While boas may spend some time slinking through their habitats looking for animals to eat, most of them are ambush hunters, which means that they find a good spot, wait motionless for a prey animal to wander by, and then strike out to grab it. The heat sensors on their faces help them "see" the heat coming from the prey, which helps them to hunt at night. The sand boas ambush prey by burying themselves in the sand and waiting for lizards or small mammals. Amazon tree boas coil around tree branches to ambush birds, and Puerto Rican boas sit still in the entrances to caves and watch for bats. Green anacondas, which are also called water boas, often lurk underwater until a passing fish or other animal comes within striking distance. Members of the boa family are constrictors, which means that the snake will kill its prey by looping its body around the animal and squeezing, cutting off the animal's air until it is dead. While most boas eat small mammals, birds, or reptiles, the green anaconda and a few of the giant species eat quite large animals, including deer and crocodilelike caimans (KAY-muhns). Some reports, although extremely rare, indicate that green anacondas have killed and eaten humans.