By Lewis Young
If you have ever watched a large wintertime flock of waxwings around Kalispell and have seen a small dark bird chasing the waxwings and exhibiting an impressive display of speed and agility, then you likely have seen a merlin. Such a sight can be seen with some frequency every winter in Kalispell.
Merlins (scientific name Falco columbarius) are small, compact, fast flying falcons. Most appear dark at a distance and females are larger than males. Males are gray-blue above, while females and juveniles are dark brown, although both sexes of the Pacific Northwest birds are almost uniformly dark. The breast and belly are streaked and the tail is barred. Merlins lack the strong facial markings of both the smaller, more common American kestrel and the larger prairie falcon. Plumage varies geographically with the three recognized races or populations of merlins. Those along the Pacific Northwest coast are darkest; the lightest are the population that breeds in the northern Great Plains from southern Canada to the northern U.S.; intermediate in color are the taiga population that breeds in the northern reaches of North America. The plumage variations among populations are well illustrated in field guides such as the National Geographic Field Guide to the Birds of North America (fifth edition) and the National Audubon Society, The Sibley Guide to Birds.
Merlins are in the true falcon family that is characterized by long pointed wings often bent at the wrist, and fast flight. Of the five species of falcons that may been seen in northwest Montana, merlins are the second smallest with wingspans of about 24 inches and a length of about 10 inches, giving them only 1-2 inch larger measurements than the American kestrel but about 6 inches shorter in length and 16 inches less wingspan than the next larger falcon, the prairie falcon. Peregrine falcons and gyrfalcons are the other two species of falcons that may be seen in northwest Montana but both species are much larger.
Merlins may be found in habitats varying from coniferous forests to isolated deciduous groves in prairies. They breed in semi-open terrain that has trees for nest sites and open areas for hunting. They may winter in more open areas such as grasslands and coastal marshes. Most merlins in North America are considered migratory and leave their breeding range to migrate into the lower 48 states and further south into Mexico and even South America, but some individuals winter in the breeding range in southern Canada, Montana, and northern Wyoming, especially in cities where house sparrows and waxwings are abundant. In North America, the vast majority of breeding range occurs north of the U.S./Canada border. Montana and northern Wyoming comprise the largest area of breeding range in the lower 48 states with small areas in North Dakota, Idaho, and Washington. Merlins also occur across the northern portions of Europe and Asia.
During courtship, the male performs spectacular flight displays with steep dives, strong twisting flight, glides, rolling from side to side, and fluttering with shallow wingbeats. He also presents food to the female. Nests are usually in old magpie, crow, or hawk nests, typically with 4 or 5 whitish eggs marked with reddish brown. Incubation is mostly by the female for 28-32 days. The male brings food to the female and she eats while he incubates. The female remains with the young most of the time after they hatch. The male brings food, the female takes it from him near the nest, then feeds it to the young, who are able to fly at around 30 days.
In Montana, merlins are widespread but uncommon to rare. In the Flathead Valley, merlins are considered uncommon during winter and rare during the summer breeding season. The Bigfork Christmas Bird Count has recorded merlins on 10 counts and the Kalispell Christmas Bird Count has recorded 1-7 merlins in each year of its 9 years.
Merlins often hunt from a perch, then fly out to capture prey in air using a burst of speed, but they will also fly low among trees or over ground and take prey by surprise. Their flight is direct, without dives or hovering. Their diet is almost exclusively small birds, although they may also take small mammals, large insects such as dragonflies, and reptiles. Like all falcons, merlins have a notched bill that is used to kill prey by severing the spinal cord at the neck.
On several occasions I have been lucky enough to watch merlins chasing prey and the display of speed and flying skills was truly amazing. Once in eastern Montana, as I walked across the prairie, a merlin used me like a bird dog, pursuing horned larks as I flushed them. The close, unobstructed view was spellbinding! Keep an eye out this winter for flocks of waxwings; by watching them for a period, you too may see how fast and agile a merlin can be. Good luck!