Merlin (Falco columbarius), earlier known as Pigeon Hawk, is a diurnal raptor, more specifically a falcon. The word "falcon", and hence the genus name "Falco", is derived from the Latin word for "sickle," in reference to the sickle-like talons and beaks of these powerful birds. Merlin preys upon pigeon-sized birds. The common name, Merlin, originated during the days of falconry when all female falcons were referred to as "merlins". Merlin is one of the smallest falcons and is anatomically adapted for swift flight.

Identification: A true falcon, with a "toothed-bill" and pointed wings, Merlins are similar in size and color to Sharp-shinned Hawks. Compactly built, this powerful and very aggressive falcon measures just 31 cm long. The adult male displays a solid, slate-blue back, while the short tail and wingtips are barred. Underneath, the creamy breast and belly are streaked with ochre and brown. Females are always larger than males, though the sexes vary in coloration. Although females and juveniles are similar in plumage, they are easily distinguishable by size. While the backs and tails of females and juveniles are brown, their creamy underparts, tails and wingtips are heavily streaked. A characteristic brown eyeline is present in all plumages.

Calls: When alarmed, the Merlin gives an accelerating series of, harsh, raucous notes that rise and taper off, "twitwitwitwititititititi." Their call is a single, hard "peek."

Nests: The Merlin often uses the abandoned nests of crows, magpies and hawks, occasionally re-lining them with twigs and feathers. In forested habitat, they may nest in high, tree cavities with defensible, commanding views. When in treeless country, they use cliffs or shallow, well-rounded, ground depressions called scrapes. Females select the nest site, build the nest and usually return to the same nest site each year. Secluded from disturbance, the nest is safe haven for the 2-7, 40mm eggs of the clutch. The eggs are white and marked with reddish brown. Although both sexes incubate the clutch, the male does all of the hunting through courtship, incubation and brooding. Young birds fledge in 30-35 days post-hatching.

Food: Ninety percent of Merlin diet is composed of small, ground-dwelling birds, such as larks and sandpipers. When small birds are not available, the Merlin switches to preying upon small mammals such as mice and ground squirrels. They also feed on insects. Female Merlins are larger than males and so are able to take larger prey. In search of prey, Merlins fly in fast, horizontal flight low over the ground. When prey is spotted, they fly swiftly to overtake smaller birds. With a blow from their open feet, Merlins knock their prey out of the air and kill it by biting the neck and severing the spinal column.