The Caprimulgidae family is the largest family in the order Caprimulgiformes. Nightjars measure 6 to 16 inches (15 to 40 centimeters) from head to tail. Their weight ranges from 0.7 to 6.6 ounces (20 to 188 grams). Plumage (feather) color includes brown, gray, brownish yellow, and rufous (reddish brown). Those colors form patterns that help nightjars hide in trees.
The nightjar has a large head with large eyes that provide the strong vision needed to see during the night. The bird's small bill opens to reveal a large gape, which is the width of the mouth when open. Nightjars have short legs and long wings and tails.
Nighthawks, a group of nightjars, don't have bristles, and they usually have longer tails and wings than nightjars.
Animal Life ResourceBirdsNightjars: Caprimulgidae - Physical Characteristics, Behavior And Reproduction, Conservation Status, Whip-poor-will (caprimulgus Vociferus): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, NIGHTJARS AND PEOPLE