Aripo Cave is a cave in the Northern Range, in Trinidad and Tobago. The caves are a notable bat roost, and that bats contribute considerable amounts of guano, which in turn support vast numbers of cave dwelling invertebates. But the caves most famous residents are the Oilbirds. These are the only nocturnal fruit eating birds in the World. They forage at night, navigating by echolocation in the same way as the bats.