The Oilbird (Steatornis caripensis) are practically bats except the fact that they are actually birds. More specifcially, they are a nocturnal frugivore in the order Caprimulgiformes.
The oilbird would roost and breed in colonies inside caves with largest colony reported to be about 10.000-18.000 individuals. The inhabit evergreens and diet on fruits and other kinds of plants. They use echolocation to allow them to navigate in the dark and smell to locate fruit.
Additionally, they have bulky nests often situated in ledges above cave floor with parental care equally shared.