Falco columbarius

Merlins are the smallest falcon species in Europe. They eat mostly songbirds, which they follow during the migration. Most of their prey consists of birds such as pipits, larks, wheatears, finches and buntings. By flying rapidly and just above the ground, they surprise these small birds. They fly the last few meters like a nistle thrush, perhaps as extra camouflage. Sometimes, merlins chase their prey long enough to tire them out so they no longer can escape.

A medium-sized (10-13 ½ inches) falcon, the Merlin is most easily identified by its size, brown-streaked breast, and black tail bands. Other field marks include dark “moustaches” on the face, dark eyes, and yellow legs. Male Merlins have slate-gray backs, while females are larger and have dark brown backs. The Merlin is widely distributed across the Northern Hemisphere. In North America, three distinct populations of Merlin occur: a darker-plumaged subspecies inhabiting the Pacific Northwest, a paler-plumaged subspecies inhabiting the northern Great Plains, and an intermediate subspecies breeding primarily in Alaska and Canada. The first two subspecies are mostly non-migratory, while the third subspecies migrates south to the western United States, the Gulf and Atlantic coasts of the eastern U.S., and south into the tropics as far as northern South America. In the Old World, this species breeds from Iceland across to Siberia, wintering as far south as North Africa and tropical Asia. Merlins breed in open areas, including forest edges, tundra, coasts, and islands. This species utilizes similar habitats in winter as in summer, but may also enter urban areas if prey is available. Merlins primarily eat small birds, which they capture either from the ground or in the air. Due to this species’ preference for open habitat, Merlins may be most easily seen perching in prominent locations or while flying in pursuit of prey. Merlins may also hunt small shorebirds, flying close to the ground in order to surprise its prey. This species is primarily active during the day.

Threat Status: Least concern

Merlins are found throughout the Northern Hemisphere. In North America they are found from eastern Canada and Alaska, south throughout Mexico. Merlins spend the winter in the southern United States, Mexico, Central America, northern South America, and the Caribbean Islands.

Biogeographic Regions: nearctic (Native ); palearctic (Native ); oriental (Native ); neotropical (Native )

Other Geographic Terms: holarctic

Merlins are found throughout the Northern Hemisphere. There are nine recognized subspecies worldwide, with three in North America: F. c. columbarius, F. c. suckleyi, and F. c. richardsoni.

Falco columbarius columbarius summers in eastern Canada, southward to Michigan and westward to the eastern border of the Great Plains. This subspecies winters in the Gulf States, eastern Mexico, northern Venezuela, Ecuador, and the West Indies.

The summer range of Falco columbarius richardsoni includes the interior of western North America. This subspecies winters in southern California, northern Mexico, and southern Texas.

Falco columbarius suckleyi is found in the northwestern coastal regions from northern California to Sitka, Alaska.

Biogeographic Regions: nearctic (Native ); palearctic (Native ); oriental (Native ); neotropical (Native )

Other Geographic Terms: holarctic

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) Holarctic distribution. BREEDS: from northward tree limit in Alaska, Canada, and Eurasia southward to southern Alaska, Oregon, Idaho, South Dakota, northern Great Lakes region, New York, Maine, Nova Scotia, British Isles, and central Russia. NORTHERN WINTER: southern British Columbia and western and southern U.S. south to Venezuela and Peru, and in Europe, extreme northern Africa, and China. Holarctic distribution.

Male merlins have slaty blue, purplish, or dark umber-brown upper parts, streaked with black from the crown to shoulders and back. The tail is barred by dark umber-brown or blackish bands and is tipped in white. The underparts are cream to a rich buff with heavy longitudinally streaks of dark umber-brown or black coloration, except for the throat which is an unmarked white. The sides of the head are buff with fine darker streakings. The forehead and line above the eye is white. The beak is bluish horn; the cere and feet are chromo yellow; the claws are black; and the iris is deep brown.

Females and young are similiar to males in their markings, but differ from males in coloration. The upperparts are dark brown. The neck is streaked with lighter brown and the tail is banded in yellow bars with a white tip.

Falco_columbarius_bendirei (Bendire's merlins): Lighter in the upper parts than Falco_columbarius_columbarius. The tail is black with three white bars.

Falco_columbarius_columbarius (American merlins): (see description of Falco_columbarius). In males, the cere and feet turn reddish with age.

Falco_columbarius_richardsoni (Richardson's merlins): Lighter overall coloration and the tail is marked by five dark and six white bands.

Falco_columbarius_suckleyi (Black pigeon hawks): Darker in overall coloration than Falco_columbarius_columbarius. The throat of males is streaked with black markings, while the lower body parts are brownish-black with chestnut and white markings. The lower parts of young males and females are heavily marked with dusky coloration and the spotting is either faint or absent from the wings.

Range length: 25 to 33 cm.

Range wingspan: 60 to 68 cm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: sexes colored or patterned differently

Average mass: 195 g.

Male merlins have slaty blue, purplish, or dark umber-brown upper parts, streaked with black from the crown to shoulders and back. The tail is barred by dark umber-brown or blackish bands and is tipped in white. The underparts are cream to a rich buff with heavy longitudinally streaks of dark umber-brown or black coloration, except for the throat which is an unmarked white. The sides of the head are buff with fine darker streakings. The forehead and line above the eye is white. The beak is bluish horn; the cere and feet are chromo yellow; the claws are black; and the iris is deep brown.

Females and young are similiar to males in their markings, but differ from males in coloration. The upperparts are dark brown. The neck is streaked with lighter brown and the tail is banded in yellow bars with a white tip.

Falco columbarius bendirei (Bendire's merlins): Lighter in the upper parts than Falco columbarius columbarius. The tail is black with three white bars.

Falco columbarius columbarius (American merlins): (see description of Falco columbarius). In males, the cere and feet turn reddish with age.

Falco columbarius richardsoni (Richardson's merlins): Lighter overall coloration and the tail is marked by five dark and six white bands.

Falco columbarius suckleyi (Black pigeon hawks): Darker in overall coloration than Falco columbarius columbarius. The throat of males is streaked with black markings, while the lower body parts are brownish-black with chestnut and white markings. The lower parts of young males and females are heavily marked with dusky coloration and the spotting is either faint or absent from the wings.

Range length: 25 to 33 cm.

Range wingspan: 60 to 68 cm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: sexes colored or patterned differently

Average mass: 195 g.

Length: 31 cm

Weight: 244 grams

Differs from American kestrel, prairie falcon, and peregrine falcon in lacking a strong facial pattern. Differs from kestrel also in lacking russet back and tail. Only about half as big as a gyrfalcon (average length 31 cm vs. 51-64 cm).

Merlins favor open country, preferring grasslands, seashores, sand dunes, marshlands, steppes, and deserts. They breed in coniferous forests of the Northern Hemisphere.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: taiga ; desert or dune ; savanna or grassland ; chaparral

Aquatic Biomes: coastal

Wetlands: marsh

Systems

• Terrestrial
• Marine

Merlins favor open country, preferring grasslands, seashores, sand dunes, marshlands, steppes, and deserts. Merlins rarely live in forested areas throughout much of their range, but frequently breed in coniferous forests of the Northern Hemisphere.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: taiga ; desert or dune ; savanna or grassland ; chaparral

Aquatic Biomes: coastal

Wetlands: marsh

Depth range based on 3 specimens in 1 taxon.
Water temperature and chemistry ranges based on 2 samples.

Environmental ranges
  Depth range (m): 0 - 0
  Temperature range (°C): 10.496 - 12.384
  Nitrate (umol/L): 4.976 - 7.963
  Salinity (PPS): 33.823 - 35.166
  Oxygen (ml/l): 6.242 - 6.362
  Phosphate (umol/l): 0.313 - 0.536
  Silicate (umol/l): 2.607 - 4.330

Graphical representation

Temperature range (°C): 10.496 - 12.384

Nitrate (umol/L): 4.976 - 7.963

Salinity (PPS): 33.823 - 35.166

Oxygen (ml/l): 6.242 - 6.362

Phosphate (umol/l): 0.313 - 0.536

Silicate (umol/l): 2.607 - 4.330
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Comments: NONBREEDING: a wide variety of habitats including marshes, deserts, seacoasts, near coastal lakes and lagoons, open woodlands, fields, etc. May roost in conifers in winter.

BREEDING: In southeastern Montana, breeding males appeared to prefer patchy shrub/grassland habitats for hunting (Becker and Sieg 1987). Urban-breeding Merlins in Saskatchewan avoided hunting in agricultural areas where prey abundance was low (Sodhi and Oliphant 1992).

Nests in conifer woodland or wooded prairie (e.g., groves of deciduous trees along rivers), including planted shelterbelts; often near water; in towns in some areas (e.g. Alberta, Manitoba, Saskatchewan). Nests in trees in abandoned crow, magpie, hawk, or squirrel nest; also in natural tree cavity or abandoned woodpecker hole, on bare cliff ledge, or scrape on ground (arctic, heather moor of U.K.). Not infrequently returns to same nesting area in successive years.

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: Yes. At least some populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: Yes. At least some populations of this species make annual migrations of over 200 km.

Most boreal birds of all ages migrate; in southern breeding range, sometimes resident or migration shorter (Palmer 1988). Northward migrants reach northern U.S. and northern Eurasia in April-May, males generally before females. Migrates southward for northern winter; migration begins in north in late August, peaks in central latitudes of U.S. September-October; migrants reach southwestern Ecuador October-November (Palmer 1988). In Puerto Rico, begins to arrive in October, departs by end of April (Rodriguez-Duran and Lewis 1985). Migrants may cross large bodies of water.

Merlins prey mainly on small birds of the ground and low vegetation, including larks (Alaudidae), sparrows (Passeridae and Emberizidae), finches (Fringillidae) and ptarmigans and grouse (Tetraoninae). Some small mammals, lizards, snakes, insects, and - in North America - dragonflies, also make up a portion of the diet. The relative proportions are about 80% birds, 5% mammals, and 15% insects.

Animal Foods: birds; mammals; insects

Merlins prey mainly on small birds of the ground and low vegetation, including larks (Alaudidae), sparrows (Passeridae and Emberizidae), finches (Fringillidae) and ptarmigans and grouse (Tetraoninae). Some small mammals, lizards, snakes, insects, and - in North America - dragonflies, also make up a portion of the diet. The relative proportions are about 80% birds, 5% mammals, and 15% insects.

Animal Foods: birds; mammals; insects

Primary Diet: carnivore (Eats terrestrial vertebrates)

Comments: Bulk of diet usually consists of small to medium-sized birds, often flocking species. Large flying insects (e.g., dragonflies) may be important for young learning to hunt. Also eats toads, reptiles, and mammals (including bats in the West Indies). Uses inconspicuous perches and searching flights when hunting. May cache prey in various seasons. Prey requirements for adults and young during 120-day breeding/rearing period: several hundred sparrow-size birds (see Palmer 1988).

Falco columbarius preys on:
Dicrostonyx
Microtus
Bombycilla cedrorum
Dendroica palmarum

Based on studies in:
Russia (Tundra)

This list may not be complete but is based on published studies.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: 81 to >300

10,000 to >1,000,000 individuals

Comments: Estimated number of breeding pairs in Canada in the early 1990s was 10,000-100,000 (Kirk et al. 1995).

At Saskatoon, Saskatchewan, breeding density was 25.4 pairs/100 sq km, the highest recorded for this species (Sodhi et al. 1992). Hunting range sizes (May-July) in Saskatoon varied from about 2-14 sq km (average 6-7 sq km) in residents to 0.6-64 sq km (average 9 sq km in females, 34 sq km in males) in immigrants; neighboring hunting ranges overlapped by 0-77% (Sodhi and Oliphant 1992).

In Montana, nestling-period home range of 3 telemetered males was 13-28 sq km; moved up to 8-9 km from nest site (Becker and Sieg 1985).

Comments: Preyed on emerging bats around sunset in Puerto Rico (Rodriguez-Duran and Lewis 1985).

Average lifespan
Status: wild: 143 months.

Average lifespan
Status: wild: 143 months.

Maximum longevity: 12.7 years (wild)

Males arrive to the breeding area before the females, usually returning to the same general area year after year. Nesting pairs don't necessarily use the same actual site each year. In open country and grassland, nests are generally scrapes located in dense vegetation. In regions of sand dunes, dune grasses may be used to create a nest. Even in wooded areas, nests may be scrapes, but empty crow nests are preferred. During the nesting period, Falco_columbarius become highly aggressive towards other raptors and crows in the area. This aggressive behavior towards other predatory birds is beneficial to other woodland song and ground birds in the nesting range; since Falco_columbarius hunts only in open country, thereby leaving the woodland birds relatively free from predators during the mating season. Normally the nest contains four to six eggs measuring 1.5 x 1.22 inches. The eggs are laid at two-day intervals. The coloration of the round oval eggs are variations of light buff white almost obscured by a regular pattern of rich chestnut-brown, purple and chocolate blotchings.

The eggs are laid in early April to early May in the southern ranges and in late May through June in the North. The female is the main incubator, although the male does share in the duties. The incubation period lasts 25-32 days. At the end of the incubation period, the eggs hatch in intervals.

Quills appear on the young after fourteen days, and by eighteen days the down is almost completely covered with feathers, except in the head region. Flight is achieved at 25-30 days after hatching.

Upon leaving the nest, the young remain nearby for several weeks until they are mature enough to migrate southward. Within a week's time of leaving the nest, the young are capable of distance flights, and at two weeks' time, they begin to catch insects. By six weeks the young are skilled in catching small birds, and shortly afterwards, they migrate southward from the breeding area. The success rate among the the young is exceptionally high, often three birds per nest survive to continue breeding.

Falco_columbarius: Breeds throughout northern Europe, Asia and North America.

Falco_columbarius bendirei: Breeds in northwestern Alaska to northern Saskatchewan and into northern California.

Falco_columbarius columbarius: Breeds in eastern Canada to the eastern border of the Great Plains and southwards into Nova Scotia and northern Michigan.

Falco_columbarius richardsoni: Breeding range is located in the Great Plains from southern Alberta and Saskatchewan to northern Montana and North Dakota.

Falco_columbarius suckleyi: Breeding occurs only in western British Columbia and perhaps on Vancouver Island.

Breeding interval: Merlins breed once yearly.

Breeding season: Merlins breed from April to July, depending on the latitude.

Range eggs per season: 4 to 6.

Range time to hatching: 25 to 32 days.

Average time to independence: 6 weeks.

Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate)

Average eggs per season: 5.

Males arrive to the breeding area before the females, usually returning to the same general area year after year. Nesting pairs don't necessarily use the same actual site each year. In open country and grassland, nests are generally scrapes located in dense vegetation. In regions of sand dunes, dune grasses may be used to create a nest. Even in wooded areas, nests may be scrapes, but empty crow nests are preferred. During the nesting period, Falco columbarius become highly aggressive towards other raptors and crows in the area. This aggressive behavior towards other predatory birds is beneficial to other woodland song and ground birds in the nesting range; since Falco columbarius hunts only in open country, thereby leaving the woodland birds relatively free from predators during the mating season. Normally the nest contains four to six eggs measuring 1.5 x 1.22 inches. The eggs are laid at two-day intervals. The coloration of the round oval eggs are variations of light buff white almost obscured by a regular pattern of rich chestnut-brown, purple and chocolate blotchings.

The eggs are laid in early April to early May in the southern ranges and in late May through June in the North. The female is the main incubator, although the male does share in the duties. The incubation period lasts 25-32 days. At the end of the incubation period, the eggs hatch in intervals.

Quills appear on the young after fourteen days, and by eighteen days the down is almost completely covered with feathers, except in the head region. Flight is achieved at 25-30 days after hatching.

Upon leaving the nest, the young remain nearby for several weeks until they are mature enough to migrate southward. Within a week's time of leaving the nest, the young are capable of distance flights, and at two weeks' time, they begin to catch insects. By six weeks the young are skilled in catching small birds, and shortly afterwards, they migrate southward from the breeding area. The success rate among the the young is exceptionally high, often three birds per nest survive to continue breeding.

Falco columbarius: Breeds throughout northern Europe, Asia and North America.

Falco columbarius bendirei: Breeds in northwestern Alaska to northern Saskatchewan and into northern California.

Falco columbarius columbarius: Breeds in eastern Canada to the eastern border of the Great Plains and southwards into Nova Scotia and northern Michigan.

Falco columbarius richardsoni: Breeding range is located in the Great Plains from southern Alberta and Saskatchewan to northern Montana and North Dakota.

Falco columbarius suckleyi: Breeding occurs only in western British Columbia and perhaps on Vancouver Island.

Breeding interval: Merlins breed once yearly.

Breeding season: Merlins breed from April to July, depending on the latitude.

Range eggs per season: 4 to 6.

Range time to hatching: 25 to 32 days.

Average time to independence: 6 weeks.

Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate)

Average eggs per season: 5.

Laying generally is completed in southeastern Montana by May 20, which is the peak date in Saskatchewan, where clutches were initiated between mid-April and late May (Sodhi et al. 1992); clutches were completed by late May in Denali Park, Alaska. Clutch size is 2-7 (average 3-5). Incubation, primarily by the female, lasts 31-32 days (male brings food). Young fledge in 25-35 days, remain dependent on parents for food 2-5 more weeks (young remained in vicinity of nest 7-19 days after fledging in southeastern Montana, Becker and Sieg 1985). First breeds at 1-2 years (occasionally 1 year). Yearling male may help nesting pair (James and Oliphant 1986). See Sodhi et al. (1992) for information on an expanding Saskatchewan population characterized by very high reproductive success.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 9
Specimens with Barcodes: 11
Species With Barcodes: 1

The following is a representative barcode sequence, the centroid of all available sequences for this species.

There are 9 barcode sequences available from BOLD and GenBank.  Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.  See the BOLD taxonomy browser for more complete information about this specimen and other sequences.

Download FASTA File

Canada

Rounded National Status Rank: N5B,N5N : N5B: Secure - Breeding, N5N: Secure - Nonbreeding

United States

Rounded National Status Rank: N4B,N4N : N4B: Apparently Secure - Breeding, N4N: Apparently Secure - Nonbreeding

Merlins are widely distributed but are not common anywhere in their range. With expanding human development, the breeding habitats and hunting grounds of these falcons are being destroyed rapidly. This species is listed as threatened in the state of Michigan.

IUCN Red List of Threatened Species: least concern

US Migratory Bird Act: protected

US Federal List: no special status

CITES: appendix ii

State of Michigan List: threatened

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

History

• 2008
  Least Concern
• 2004
  Least Concern

Falco columbarius is widely distributed, but nowhere common. With expanding human development, the breeding habitats and hunting grounds of these falcons are being destroyed rapidly. This species is listed as threatened in the state of Michigan.

US Migratory Bird Act: protected

US Federal List: no special status

CITES: appendix ii

State of Michigan List: threatened

IUCN Red List of Threatened Species: least concern

Regular passage visitor and winter visitor.

Rounded Global Status Rank: G5 - Secure

Reasons: Widespread (Holarctic) distribution; increasing population trends in areas formerly negatively impacted by pesticide pollution; still threatened in some areas by habitat loss; organochlorine use in Central and South America poses a threat.

Degree of Threat: B : Moderately threatened throughout its range, communities provide natural resources that when exploited alter the composition and structure of the community over the long-term, but are apparently recoverable

Comments: Pesticides contributed to a decline, particularly in Europe, in productivity recorded in a 20-year period prior to the early 1970s (Trimble 1974). Primary threats include habitat loss and continued use of organochlorine biocides in Central and South America.

Global Protection: Unknown whether any occurrences are appropriately protected and managed

Comments: In the U.S., many EOs occur on federally owned land; however EOs may change year to year.

Needs: Limit pesticide use to levels that do not affect reproduction. Protect habitat.

The diet of merlins consists mainly of small birds, including many small birds which are a benefit to agriculture and forestry. In the northern part of their breeding range merlins sometimes attack small domestic poultry, but these attacks are rare.

Merlins occasionally prey on agricultural insect pests, such as Orthoptera. They are also widely used in falconry. Considered a lady's gaming bird, merlins are relatively easy to train for small game hunting and are usually returned to the wild after a season.

Positive Impacts: pet trade ; controls pest population

The diet of Falco columbarius consists mainly of small birds, including many small birds which benefit agriculture and forestry. In the northern the breeding range, Falco columbarius individuals sometimes attack small domestic poultry; however, these attacks are quite rare.

Merlins occasionally prey on agricultural insect pests, such as grasshoppers and crickets. These small falcons are also widely used in falconry. Considered a lady's gaming bird, Falco columbarius is relatively easy to train for small game hunting and usually returned to the wild after a season.

Positive Impacts: pet trade ; controls pest population