All about the Northwest Merlin

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Artist: Roger Stillman

Life cycle
Taxonomy & Etymology
Identification
Vocalization
Migration
Winter
Breeding
Habitat
Food
Behavior
Population Status & Distribution
Interdependence 

Life Cycle (click to enhance)

Taxonomy And Etymology

Nine subspecies (including the three in North America) of Merlin are found worldwide above 47 degrees north latitude. The Coastal Forest Merlin breeds in the Temperate Coastal Rain Forest, the Taiga Merlin in boreal forest and tundra (taiga), and the Prairie Merlin in prairies and parklands. Subspecies type specimens reside in the National (Smithsonian) Museum in Washington D.C. and the University of North Carolina. The Coastal Forest Merlin Project follows Dr. Stanley Temple’s 1970 master’s thesis study of North American Merlin ecozone designations.

The Merlin was previously known in North America as the Pigeon Hawk because it looks and flies like a pigeon. The species name of the Merlin refers to the genus of the pigeon, Columba, transferred to columbarius, of the Merlin. Merlin derives from the old French Faucon ésmerillon and Spanish Esmerejón. Falco means hooked bill and curved or scythe-like talons (claws). Suckleyi refers to naturalist Dr. George Suckley, who with Dr. John G. Cooper and G. Gibbs accompanied the Northern Pacific Railroad Survey, commanded by Isaac I. Stevens, governor of Washington Territory. They explored roughly along the 47th parallel between St. Paul, MN and Puget Sound on the Pacific coast in 1853-1855. Suckley’s reports on the mammals, water birds, and fishes collected during the expedition appeared in the official publication issued by Isaac I. Stevens (Supplementary Report of Explorations for a Route for a Pacific Railroad (1859), volume 12 of Pacific Railroad Surveys.) Dr. Suckley collected the type specimen of the “Black” Merlin at Shoalwater Bay, Washington. A type specimen is the original on which all descriptions are based. This juvenile male specimen, a dark melanin-saturated individual, now resides in the National (Smithsonian) Museum.

Identification

The so-called Black Merlin (most field guides still refer to it by this name) is not really black, but chestnut brown on the back and white with dark or chestnut brown streaks underneath (throat to lower abdomen). Second-year males molt into the purple-blue back color (as seen in sunlight; otherwise it looks dark brown) while adult and juvenile females retain the dark or chestnut brown coloration year round. This is called sexual dichromaticism, which is unique to the Falconidae. Females are ¼ larger than the male, which is called sexual dimorphism.

Older avian references refer to four Merlin subspecies in North America; the fourth one, F. c. benderi, was a paler form of the Taiga Merlin of the western continent. Temple and other modern taxonomists believe this is no longer a valid subspecies.

Vocalization

Merlins have a variety of vocalizations (calls). Published literature on Merlins suggests that their call is a high-pitched version of the larger falcons. Falcons have a staccato cadence. The standard male Merlin’s call is described as a kee-kee-kee, similar to the Douglas Squirrel of the Northwest, but slightly higher and shorter. This sound frequency travels very well in semi-open forest canopies (tree tops). One of the female calls is similar to the male but lower-pitched.

Other vocalizations accompany different behaviors, i.e. food soliciting, agitation, when near the nest, and defending the nest against predators. Merlins may also sound like a Dark-eyed Junco male singing, American Robin male agitation call, Northern Flicker, Pileated Woodpecker, or other species when heard at a distance with wind or creek sounds partially masking or obscuring the call. Commercial bird recordings present a captive Merlin who is given food and then the food is taken away; the Merlin responds with an upset or agitated call in response.

Male Merlin chittering #1

Male Merlin chittering #2

Female Merlin soliciting food

Male Merlin: agitating at Northwest Crows

Migration

Merlins disperse from natal (birth) sites and migrate in a broad range of North American habitats. Distance and direction of F. c. suckleyi migration is unknown because there is no data available from banding. Competent biologists suggest there is migration into mid-California.

Winter

Climatic influences determine the presence of songbirds and their Merlin predator outside of the breeding season. In temperate environs both songbirds and Merlins may remain through mild winters. However, some individuals, perhaps from northern latitudes, may travel farther south. Our study and a few experienced observers conclude that during winter Taiga Merlins outnumber Coastal Forest Merlins in Washington.

Breeding

Coastal Forest Merlins begin their courtship activities in February-March. Males and females call and chase each other in elaborate and ritualized displays. Male Merlins show females nesting platforms and bring them food. Females also hunt but become increasingly sedentary, possibly to test the male’s ability to provide her with food. If she stays in the pair bond she’ll lay 3-5 eggs in late April-early May. Hatching is in late May-early June. Nestlings fledge in 4-5 weeks. Fledglings may remain around the breeding territory for another 4-5 weeks, learning to hunt.

Habitat

Northwest Coastal Forest Merlins are found during the breeding season in ancient (old-growth) to young forests where nest platforms are available. In the last 15 years nesting has also occurred in urban settings of Washington and British Columbia. During migration and winter, Coastal Forest Merlins may be found in diverse habitats where their prey species occur.

Food

American Dipper

Merlins are bird-prey specialists focusing on passerine (perching songbirds) and shorebirds. They also take aerial insects and a very small number of mammals. In the Northwest, Merlins eat a wide variety of resident and Neotropical migrants (birds that migrate from Central and South America).

Behavior

Merlin’s annual behavioral ecology is a fascinating study subject and a core element of our project. Fieldwork, data entry and analysis continue so we can share the untold story of this enigmatic forest falcon.

Population Status And Distribution

Coastal Forest Merlins appear uncommon to rare, but their true status is still regionally undetermined. 30 years of fieldwork in Washington provides the empirical evidence that Coastal Forest Merlins are less common than Bald Eagles, Peregrine Falcons, Spotted Owls, and Marbled Murrelets-all threatened or endangered species.

The Coastal Forest Merlin’s historical distribution was presumed to be from southern Puget Sound in Washington to northern British Columbia west of the Cascade and Coast mountain ranges. Current distribution may be similar but is still being refined and will take a considerable effort to confirm. Appropriate habitat for the annual life cycle is also constantly fluctuating, probably in response to human-modified landscapes.

Integrating Northwest people’s lifestyles with those wildlife communities with whom we share the land is an achievable goal. We believe that knowledge about salmon, eagles, amphibians, bats, Merlins and other wildlife helps us all to understand and maintain the diversity we all need in our lives.

Interdependence

John D. Dawson

Salmon, elk, eagles, orchids, people and Merlin all depend on a healthy and diverse ecosystem. Seeds, fruits and insects feed young and adult songbirds who are, in turn, sustenance for this predatory falcon. Diverse elements like these are a constantly interacting food web, a tapestry of opportunities for the Merlin and you.