Monday, April 18, 2011
Merlin (Falco columbarius)
The Merlin is a small falcon -- similar in size to a blue jay -- of the prairies, boreal forests, and subarctic areas of North America. Males average 24-27 cm long, with a wingspan of 53-58 cm. As in most raptors the females are somewhat larger, with measurements of 28-30 cm and 61-68 cm, respectively. Merlins are unusual among raptors in that the sex of adults can be told apart by plumage. Males are slate blue-gray above, with bold black tail bands; females are brown with buff-coloured tail bands. Both have a whitish throat and a buff breast moderately to heavily streaked with brown. In general the plumage of juveniles is similar to that of adult females. I would call this an adult female. She was waiting for her mate while I was photographing. When he arrived they both fluttered off with their "keek, keek, keek" spring mating calls.
Its scientific name is Falco columbarius - a reference to its original North American name of "pigeon hawk," as columbarius means "pertaining to a dove or pigeon" in Latin. “Pigeon hawk” alluded to the Merlin’s pigeon-like flight, though it does in fact prey on pigeons. I’ve seen a Merlin take down a Rock pigeon a good number of times on the campus of the University of Alberta. The Old French esmerillon is the root of both "Merlin" and the modern French name for the species, "Faucon émerillon.
In the photo above you see what appears to be a streak of blood on its undertail. Likely mess left after a recent kill. The bulk of their diet consists small songbirds. When hunting, the Merlin typically flies over open forest or grassland at high speed (up to 70 km/h), flushing out birds and snatching birds who react too slowly. Merlins are extremely agile, able to make remarkably rapid changes of direction to keep up with their quarry. Alternatively, Merlins may hunt by watching for activity from a perch, and then launching into rapid flight from there. Merlins also feed on insects, especially in migration when they often grab dragonflies or butterflies out of the air and eat them while in flight.
The Merlin is rapidly colonizing urban areas on the prairies. It is the most abundant hawk in the city precincts of Edmonton. I have seen it hunting in my backyard, even colliding with my living room window. At the moment, they are noisily courting and establishing nesting territories.