» This article is about the bird. For the aircraft, see Gloster Nightjar. Nightjars are medium-sized nocturnal or crepuscular birds with long wings, short legs and very short bills. They are sometimes referred to as goatsuckers from the mistaken belief that they suck milk from goats (the Latin for goatsucker is Caprimulgus). Some New World species are named as nighthawks. Nightjars usually nest on the ground. Nightjars are found around the world. They are mostly active in the late evening and e… (More on Caprimulgidae)