Hawking is a feeding strategy in birds involving catching flying insects in the air. The term usually refers to a technique of sallying out from a perch to snatch an insect and then returning to the same or a different perch, though it also applies to birds that spend almost their entire lives on the wing. This technique is called "flycatching" and some birds known for it are several families of "flycatchers": Old World flycatchers, monarch flycatchers, and tyrant flycatchers. Other birds, such as swifts, swallows, and nightjars, also take insects on the wing in continuous aerial feeding. The term "hawking" comes from the similarity of this behavior to the way hawks take prey in flight, although, whereas raptors may catch prey with their feet, hawking is the behavior of catching insects in the bill. Many birds have a combined strategy of both hawking insects and gleaning them from foliage. Flycatching The various methods of taking insects have been categorized as: gleaning (perched bird takes prey from branch or tree trunk), snatching (flying bird takes prey from ground or branch), hawking (bird leaves perch and takes prey from air), pouncing (bird drops to ground and takes prey) and pursuing (flying bird takes insects from air). In hawking behavior, a bird will watch for prey from a suitable perch. When it spies potential prey, the bird will fly swiftly from its perch to catch the insect in its bill, then return to the perch or sometimes to a different perch. This maneuver is also called a "sally". Prey that is very small relative to the bird, such as gnats, may be consumed immediately while in flight, but larger prey, such as bees or moths, are usually brought back to a perch before being eaten. Sometimes the prey will attempt to escape and this can result in a fluttering pursuit before returning to the perch. Depending on the species of bird, there are observable variations on this behavior. Some species, such as the olive-sided flycatcher of North America and the ashy drongo of the Indian Subcontinent, tend to choose an exposed perch, such as a dead tree branch overlooking a clearing, whereas others, such as the North American Acadian flycatcher and the Asian small niltava perch within the cover of foliage deep in a forest or woodland habitat. Many birds make use of a variety of tactics. A study of feeding behaviors