Merlins

© 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

northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There's also a community-type page for The Northeast Naturalist.

Kestrels

American Kestrels (revised with new links and photos)

© Dave Spier

They're easiest to see when they sit on power lines and watch the grass below. In the absence of these utility perches, they may simply turn into the wind and hover on beating wings. Oil droplets coating the bird's eyes filter out haze and glare. Retinas, each packed with a million light-collecting cells, give it vision eight times better than a human's. Theoretically they could see a mouse from the top of the Empire State Building. After prey is spotted, the hawk drops like a stone and reaches out with needle-sharp talons. I've also heard of them gliding downhill and grabbing a mouse running across the snow, a most foolish thing for rodents to do. This maneuver caught the attention of two crows which gave chase, causing the kestrel to drop its prey. Undaunted, the hawk circled back and retrieved its fallen victim.

The American Kestrel, Falco sparverius, was once known as the sparrow hawk, a name derived from its habit of eating small songbirds, but in reality these comprise only one-third of the hawk's winter diet. On an annual basis, mice and other small rodents, plus a few frogs and reptiles represent a much larger proportion of its intake. During warm weather it eats primarily insects, and late in summer the kestrel dines almost exclusively on juicy grasshoppers which are plentiful and easy to catch. This earned the bird the nickname "grasshopper hawk" from early ornithologists. Kestrels also eat crickets, cicadas, moths, beetles and ants. Small snakes are readily dispatched, but large snakes present a problem if they wrap themselves around the bird's legs. Small roadkills, and songbirds that fly into windows, are a source of easy meals.

Kestrels are the smallest members of the falcon family, a group that is no longer considered close relatives of the true hawks. Male kestrels are nine inches long while the larger females may reach 12 inches. On average they're about the size of a robin or blue jay which makes all these birds vulnerable to larger winged predators, especially Cooper's Hawks. On the other hand, kestrels will not tolerate competitors in their hunting territory and have been known to chase off larger, but less agile, raptors like the redtail. The falcon family also includes the kestrel's larger and more famous cousin, the Peregrine, which is uncommon in the northern Finger Lakes Region of New York.

If you're close enough, kestrels are easy to recognize. In addition to small size, on a white face look for bold black marks creating a "mustache" and "sideburns." Males have gray wings and rusty-red tails ending with a black band and white feather tips. Females are mostly rufous-brown with fine cross-barring on the back, wings and tail. The lighter undersides of both are spotted, giving way to white under the tail. The wings and tail are relatively long, much like the larger harriers which also hunt the open countryside. (Harriers, also displaying sexual plumage dimorphism, are in a different family.) Unlike harriers, falcons are noted for flying with pointed wingtips, an advantage for faster speed. Peregrine falcons, which can reach a diving speed of 200 mph, are the fastest animals on earth.

Kestrels are year-round residents throughout New York and most of the United States, and a summer breeder across much of Canada and the northern Great Plains states. You can find an interactive range map on eBird under Explore Data -> Range...Maps.

Kestrels nest in tree cavities, often taking over old woodpecker holes, but the cutting of dead trees for firewood results in a shortage of natural nesting cavities. Fortunately, kestrels readily take to large nest boxes erected specifically for the purpose. The size should be at least eight inches square inside and 15 inches tall with a three-inch entrance hole centered three inches below the top. Mount it at least 10 feet above the ground. As controllers of insect and mouse populations, kestrels are valuable to gardeners and farmers, and nest boxes are one way to encourage their presence.

For more information, visit All About Birds.

Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. Other nature and geology topics can be found on the parallel blogs Adirondack Naturalist and Heading Out. There's also a community-type page for The Northeast Naturalist.