At the end of a trail at Asa Wright Nature Centre in Trinidad we were given the option of wading into a stream which went into a dark ravine to try and see some roosting oilbirds. Oilbirds ususally roost in caves but this ravine defnitely had some dark places. They have a strong hooked bill with large dark eyes. When foraging at night they give a slow stream of clicks (audible to humans) which are used for navigation by echo location. Colonies vary from a few pairs to 1000s depending on size of cave, suitable ledges for nests, and food. The largest colony (10,000-18,000) birds is at PN Cueva del Guacharo, Venezuela. One colony recently found near top of Cerro Roraima, 2600m, Feb 2000 is highest in Venezuela. It is the only nocturnal fruit eating bird in the world. f/7.1, iso 1600, exp comp minus 2.0, 1/8. Considerably lightened in photoshop. Uncropped.