The nightjar is a nocturnal bird that can be found throughout Asia and Europe during the summer months and in parts of Africa during the winter. Small birds with long tails, they are members of the Caprimulgidae family. Their unique coloring camouflages them during the day, when they are resting and not actively looking for food.
A somewhat strange-looking bird, the nightjar has a wide head with a flat forehead and tiny beak. Its eyes are large, allowing it to see and hunt better when active at night. Plumage is mottled shades of brown, resembling the bark of a tree and helping to camouflage the bird during the daytime, when it remains in the nest or in trees. Males and females look similar, except the male has distinctive white feathers on his wings. The body of the nightjar is barrel-shaped, and it has a long, slender tail, reaching an overall length of 10 to 11 inches (26 to 28 cm).
During the warmer summer months, the nightjar is found across Europe and Asia as far west as the United Kingdom and as far east as China. Nightjars migrate to Africa in the winter. They are commonly found nesting in open moorlands, wooded clearings, and in areas were trees have recently fallen or been cut. They are also commonly seen in open, flat areas used for grazing livestock, and their long association with these places gave rise to the centuries-old myth that they survive on the milk of goats. In fact, the different species of nightjars, including the Sunda nightjar and the Egyptian nightjar, are members of the genus Caprimulgus, a word that translates as goat-sucker.
Nightjars make their nests on the ground, typically in areas with bracken that will camouflage the birds while they are sitting on the eggs. The courtship rituals are made up of complicated, airborne displays, and culminate in the laying of eggs between the middle of May and the middle of July. It is suspected that the breeding cycle of the nightjar corresponds to the phases of the moon, and it has been documented that birds are more active during the brighter lunar phases. After the young nightjars leave the nest, adults and juveniles alike head to their wintering grounds in Africa, usually leaving their breeding grounds in August or September.
Nightjars around the world are threatened by human encroachment on their territories. Expanding cities and other building projects take nesting grounds away from them, and their food sources are also being decreased. Preying mainly on insects like beetles and ants, they are finding less and less to prey on with increased use of pesticides.