Oilbird

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{{Taxobox | color = pink | name = Oilbird | image = Guacharo.jpg | regnum = Animalia | phylum = Chordata | classis = Aves | ordo = Caprimulgiformes | familia = Steatornithidae | familia_authority = Bonaparte, 1842 | genus = Steatornis | species = S. caripensis | binomial = Steatornis caripensis | binomial_authority = Humboldt, 1817 }} The Oilbird (Steatornis caripensis) is a slim, long-winged bird related to the nightjars. It is sufficiently distinctive to be placed in a family and suborder (Steatornithes) of its own. It is found in the northern areas of South America and the island of Trinidad in forests and woodland with caves. It is a seasonal migrant, moving from its breeding caves in search of fruit trees.

This nocturnal species, uniquely, is a specialist feeder on the fruit of the Oil Palm and tropical laurels. All the other nightjars and their relatives are insectivores.

The Oilbird's feet are small and almost useless, other than for clinging to vertical surfaces. However, it is capable of hovering and twisting flight, which enables it to navigate through restricted areas of its caves.

This is a large bird at 41-48 cm. with a hooked bill and stiff tail feathers. it is mainly reddish-brown with white spots on the nape and wings.

During the day these gregarious birds rest on cave ledges. The nest is a heap of droppings, on which 2-4 white eggs are laid. Although the Oilbird forages by sight, it is one of only a few birds, and the only nocturnal one, known to navigate by echolocation in sufficiently poor light conditions.

Image:CuevaDelGuacharo.jpg The Oilbird produces a variety of harsh screams in its caves, and also a sharp click used for echolocation. One of the most accessible, but by no means the largest nest location is Dunstan Cave, at the Asa Wright Nature Centre, Trinidad, which holds about 200 pairs. Other sites may have up to 2,500 nests or more.

The oilbird is called a "guácharo" or "tayo" in Spanish, both terms being of indigenous origin. The "Cueva del Guácharo" (Oilbird Cave), in the mountainous Caripe district of northern Monagas, Venezuela, is where Alexander von Humboldt first studied the species. The caripensis of the binomial name means "of Caripe", and Steatornis means "fat bird", and refers to the fact that the squabs become very fat before fledging, coming to weigh half again as much as the adult birds do. They used to be harvested and rendered for oil, whence the name "oilbird".

These birds have been reported in various places along the Andean mountain chain and in Brazil: they are known to dwell as far south as the Carrasco National Park in Bolivia.

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