Falco columbarius

Least Concern

The merlin is a predominantly ground nesting falcon and the UK’s smallest bird of prey. Preferring upland and moorland areas for breeding the bird may venture in to lowland regions during the winter when it is joined by migrating merlins from Iceland.

Appearance and Identification

Primary Color

Bluish Gray

Primary Color (female)


Primary Color (juvenile)


Secondary Colors

White, Brown

Secondary Colors (female)

White, Black

Secondary Colors (juvenile)

White, Black

Secondary Colors (seasonal)

Wing Color

Bluish Gray

Wing Color (female)


Wing Color (juvenile)


Beak Type


Beak Color


Beak Color (female)


Beak Color (juvenile)


Leg Color


Leg Color (female)


Leg Color (juvenile)


Distinctive Markings

Dark banding on tail, streaked underparts

Distinctive Markings (female)

Darker streaking on underparts, up to 30% larger than males

Distinctive Markings (juvenile)

Fainter streaking on underparts

Tail Description

Short and square

Tail Description (female)

Short and square

Tail Description (juvenile)

Short and square

Size Metrics

24cm to 33cm


53cm to 69cm


165g to 230g



Click on an image below to see the full-size version

Vocalization and Sounds

Primary Calls

High-pitched chittering and kee-kee-kee sounds

Call Description

Rapid series of high-pitched notes, often given in flight

Alarm Calls

Sharp, loud klee-klee-klee

Behavior and Social Structure

Daily Activities

Active during the day, particularly at dawn and dusk

Social Habits

Mostly solitary, forms pairs during breeding season

Territorial Behavior

Defends nesting territory aggressively, particularly against larger raptors

Migratory Patterns

Populations in northern range migrate south for winter

Interaction with Other Species

Occasionally forms mixed-species flocks during migration


Primary Diet

Small birds, Insects

Feeding Habits

Hunts from a perch or in flight, often catching prey mid-air

Feeding Times

Primarily crepuscular, with peaks at dawn and dusk

Prey Capture Method

Stooping and pursuit flight

Diet Variations

Diet varies with season and location, includes more insects in summer

Special Dietary Needs (if any)

None known


Nesting Location

In old crow or raptor nests, on cliffs or in trees

Nest Construction

Does not build its own nest, uses existing structures

Breeding Season

Spring to early summer

Number of clutches (per breeding season)

1 brood

Egg Appearance

Pale blue with brown spots

Egg Size

Approximately 4cm x 3cm

Clutch Characteristics

3-6 eggs, usually four

Incubation Period

Around 28 days

Fledgling Period

Approximately 4 weeks

Parental Care

Both parents feed chicks, female primarily incubates eggs

Distribution and Habitat

Geographic Range

Widespread across Northern Hemisphere, from tundra to desert habitats

Habitat Description

Open country, forests, coastlines, and cities

Elevation Range

Sea level to 2000m

Migration Patterns

Populations in northern range migrate south for winter


Forest, Grassland, Desert

Climate zones

Polar, Temperate, Subtropical

Distribution Map

Please note, this range and distribution map is a high-level overview, and doesn't break down into specific regions and areas of the countries.

© 2024 - Birdfact