Similar species Falconidae

American Kestrel |  Amur Falcon |  Barbary Falcon |  Eleonoras Falcon |  Gyrfalcon |  Hobby |  Kestrel |  Lanner Falcon |  Lesser Kestrel |  Merlin |  Peregrine Falcon |  Red-footed Falcon |  Saker Falcon | 

Stocky, small and dashing falcon. Male has upperparts dark or pale bluish, underparts from dark and heavily streaked to pale buff and lightly streaked, usually conspicuous pale bands in tail. Female browner, without blue tones, plumage generally more uniform, less contrasted than in male. Juvenile similar to female. Races differ in overall plumage tone, suckleyi darkest, pallidus palest, also small difference in size.

Merlins typically nest in boreal forest, preferrably near bogs or open water. Lake shores and islands are used most frequently with fewer inland nest reports. These open to semi-open areas are chosen probably to facilitate hunting. Merlins are likely limited by adequate food items and a source of available nesting sites. The food base is normally provided by small to medium-sized birds of grasslands, wetlands, or forest edges. Merlins do not build there own nests but use those of other birds, most commonly those of corvids (crows, ravens). Rarely they nest in tree cavities, on cliffs, or on the ground. Lake shorelines and other open areas are used as hunting grounds, although merlins will also commonly hunt within the forest.

This falcon inhabits moors and fens at high altitude in northern Eurasia and North America. In the British Isles it has a definite preference for heather (Erica) and bracken (Pteridium aquilinum). Its European populations are wintering throughout the continent and reach northern Africa. The breeding population of the European Union (12 Member States), entirely restricted to the British Isles, has undergone a strong decline between 1950 and 1960 following the widespread use of organochlorine pesticides in its winter quarters. Since 1980 it is increasing again, but its future is largely dependent on the management of its habitat for Red Grouse (Lagopus lagopus)

Merlins feed primarily on small to medium-size birds, but will take insects, rodents, and small lizards. They have been known to take birds as large as pigeons but more often they take small passerines or shorebirds weighing less than 50 grams.

This species has a large range, with an estimated global Extent of Occurrence of 10,000,000 km². It has a large global population estimated to be 100,000-1,000,000 individuals (Ferguson-Lees et al. 2001). Global population trends have not been quantified; there is evidence of population fluctuations (Ferguson-Lees et al. 2001), but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e. declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern. [conservation status from birdlife.org]

Merlins begin breeding at two years of age and use old nests of other species, such as ravens, crows, or hawks, in which they lay a clutch of 4-5 eggs. The female does most of the incubation during the 28-32 day period and is fed by the male. The young fledge 25-30 days after hatching and are dependent upon the adults for another 4-5 weeks. Merlins are almost entirely diurnal hunters but occasionally they will hunt at dusk when bats are taken. Food caching has been recorded both during the breeding season as well as on the wintering grounds. Fledglings sometimes at play will half-heartedly chase potential prey species. The young remain together after fledging and may migrate south together.

Mainly migratory, but some birds resident, especially in extreme west. Some European breeding birds present in winter in a few peripheral moorland breeding areas; in general, withdraws south for winter, or, especially in Britain, makes altitudinal movements from moorland to coasts. Difficult to establish whether winter records from breeding areas relate to residents or migrants from elsewhere. Autumn passage starts August in Scandinavia and north Russia, with peaks at Ottenby and Falsterbo (south Sweden) in September; from western Europe and Alps southwards, main movements in October. Return passage begins late February in south; most birds within breeding range by late April, though high arctic areas may not be reoccupied until May.