Nightjars are medium-sized nocturnal or crepuscular birds in the family Caprimulgidae, characterized by long wings, short legs and very short bills. They are sometimes called goatsuckers, due to the ancient folk tale that they sucked the milk from goats (the Latin for goatsucker is Caprimulgus), or bugeaters, due to their insectivore diet. Some New World species are called nighthawks. The English word 'nightjar' originally referred to the European nightjar.

Nightjars are found around the world. They are mostly active in the late evening and early morning or at night, usually nest on the ground, and feed predominantly on moths and other large flying insects.

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