© Dave Spier
The Merlin (Falco columbarius) was once known as the Pigeon Hawk, a strong indication of its diet, even though it's about the same size as a pigeon. Unfortunately it also captures and consumes smaller birds. The Merlin is a very fast flier, nicknamed the "bullet bird," and intermediate in speed between the slightly-smaller kestrel and the larger Peregrine. Like all falcons, the wing tips are usually pointed. Accipiters fly with rounded wings. The Merlin somewhat resembles the Peregrine in appearance but without the bold facial pattern. The adult male Merlin is gray on the back, streaked on the front, and has a weakly-barred, dark tail and a thin, white stripe above the eye. Females and juveniles are dark-brown on the back, streaked underneath and often have more white on the throat, while males are buff or light brown underneath. Some individuals show a dark tail with narrow, whitish bands.
Perched juvenile Merlins can sometimes be misidentified as a juvie Accipiter. Get a photo if at all possible. When I was at the Audubon Center, we had such a case, but in the photo, a small detail in the shape of the bill was the key. Falcons have a notch in the upper mandible toward the tip; it's used to break the neck of its prey as I recall. The notch is often hard to see, though.
Merlins nest at higher elevations, primarily in areas like the Adirondacks, and then disperse and wander after the breeding season. They also breed across most of sub-arctic Canada and Alaska in the Boreal Forest zone and the northern prairies. They prefer open woods and edges. Unlike kestrels which lay their eggs inside tree cavities or nest boxes, Merlins take over nests of other raptors or crows in the open tree tops.
During migration they can turn up anywhere in the continental United States, and most Merlins spend the winter from coastal Alaska down through the western states to the Gulf coast and northern South America according to one range map. Other maps include the Great Plains in its winter range. I'm writing this now because I just had a Merlin on top of a conifer (last two photos) in the northern part of the Finger Lakes region of New York. (This is not the first winter I've seen them around this area.) They prefer open woodland, but can be found in grasslands, fields, marshes and seacoasts.
For more information, photos and sounds, visit the All About Birds website. An interactive range map (zoomable to your location) can be found in the eBird Explore Data section.
Corrections, comments and questions are always welcome at