The merlin falcon, or Falco columbarius, is a small bird of prey found throughout North America, Europe and Asia. Merlins range from 9.5 to 13 inches (24 to 33 cm) in length, have a wingspan of about 20 to 26 inches (50 to 67 cm) and weigh approximately 5.3 to 9 ounces (150 to 255 grams). In appearance, the merlin falcon has a long, banded tail and lengthy, pointed wings. Coloration differs between the sexes with the wings and back of the male being blue-gray and the female being brown. Its talons are black, and its legs and feet are yellow.
Merlin falcons are primarily birds of the northern prairies and forests. Geographically, the species is found in the northern hemisphere and is distributed worldwide in regions above 47 degrees north latitude. Merlins are migratory, however, and most will move south when the weather turns cool. North American populations move to the southern United States and northern South America. The northern European species move southward to North Africa and southern Europe.
For habitat during the non-breeding season, the merlin falcon prefers country that is fairly open such as scrub or shrub lands, prairies, lake shores and moorland. Generally speaking, this type of falcon likes a mixture of low- to medium-height vegetation with at least some trees. It is known to avoid treeless, arid regions as well as dense forests.
During breeding season, however, the merlin falcon’s habitat expands to include coniferous forests as it searches for nest sites that offer dense vegetation or rocky cover. The merlin falcon frequently does not build its own nest. Instead, it often will use the abandoned nests of other birds.
After the migration to breeding grounds is completed, usually no later than the end of spring, the male puts on a variety of aerial displays designed to attract a female to his territory. He will bring her food and show her the proposed nest. Generally, merlin falcons are monogamous during the breeding and nesting season. A clutch of two to five eggs is laid, and it will hatch in approximately 28 to 32 days. The male merlin keeps the female fed, but both parents defend the nest and feed the nestlings.
The merlin falcon is carnivorous and preys mostly on small to medium-size birds. Insects and small mammals, such as bats and mice, provide variety in its diet. Merlins are regarded as very able aerial foragers, and they capture most of their prey in the air. Seemingly unafraid, Merlins have been known to try to catch even large prey, such as automobiles.