Animal
Common cuckoo
The common cuckoo is a gray bird with a striped belly. The male calls cuck-oo! The mother cuckoo lays her eggs in other birds' nests, and those birds raise her chicks.
The common cuckoo is a sleek, gray bird with a barred belly, a long tail and pointed wings. Each spring it flies from Africa or southern Asia to breed across Europe and Asia, where the males call their famous cuck-oo. Cuckoos never build nests: a female lays each egg in the nest of another bird, such as a meadow pipit or a warbler, and the foster parents raise the young cuckoo.
Cuculus canorus is a long-distance migrant and obligate brood parasite that breeds across Europe and Asia and winters in Africa and southern Asia; over 100 host species have been recorded. BirdLife International assessed it as Least Concern for the IUCN Red List (assessed 14 May 2024, published 2024), with a very preliminary estimate of 34.6 to 54.4 million mature individuals and a stable global trend, though western European populations have declined.
Photo: Andy Morffew, CC BY-SA 4.0, via Wikimedia Commons
Meet the cuckoo
The cuckoo is about as big as a dove.
It has a gray back and a belly with black and white stripes. It has a long tail.
The common cuckoo is about the size of a dove. It has a blue-gray head, back and chest, a belly striped in black and white, a sleek body, a long tail and pointed wings. The RSPB says this shape makes it look rather like a kestrel or a sparrowhawk.
A cuckoo is about 32 to 34 centimeters long and weighs about 105 to 130 grams. Most people recognize its call, which spells out its name.
Cuculus canorus belongs to the cuckoo family, Cuculidae. The RSPB gives a length of 32 to 34 centimeters, a wingspan of 55 to 65 centimeters and a weight of 105 to 130 grams, describing a dove-sized bird with a blue-gray back, head and chest, a barred black-and-white belly, yellow legs and a sleek, long-tailed, pointed-winged shape not unlike a kestrel or sparrowhawk; the British Trust for Ornithology (BTO) lists an average weight of 114.3 grams.
The IUCN assessment recognizes several races with different wintering areas, including the nominate race, bangsi of Iberia, bakeri of Asia and subtelephonus, which migrates through the Middle East (Payne and Christie 2013).
Quick facts
- Group
- Bird
- Length
- 0.32 to 0.34 m
- Wingspan
- 0.55 to 0.65 m
- Weight
- 0.11 to 0.13 kg
Summer in the north, winter in the south
Cuckoos spend the summer in Europe and Asia.
Then they fly far away to Africa or southern Asia for the winter.
Common cuckoos live in many kinds of open and wooded country: forests and woodlands, scrub, heaths, meadows, reedbeds and moors. They breed across Europe and Asia, from Ireland and Portugal to Japan.
They are long-distance migrants. Cuckoos breeding in Europe spend the winter in Africa, and many breeding in Asia winter in India, Southeast Asia or Africa. In Britain, males arrive in late April.
The IUCN lists breeding range across Europe and Asia, a resident listing for many African, some Asian and a few European countries, and passage across the Middle East, with the species found up to 3,800 meters. It describes forests and woodlands, both coniferous and deciduous, second growth, open wooded areas, wooded steppe, scrub, heathland, meadows, reedbeds, lowlands and moorland.
After Payne and Christie (2013), the IUCN text says nominate birds breeding from the British Isles and Scandinavia east to Russia winter in central and southern Africa; Iberian bangsi winter south of the equator from West Africa to Lake Tanganyika; Asian birds winter in India, Southeast Asia, the Philippines and Africa. The BTO calls the cuckoo a summer visitor to Britain, with males arriving in late April.
Continents
Its habitats
Where can you find this animal?
- Lives here naturally · Countries and seas named by a scientific source
- Sightings recorded · Records of wild sightings (GBIF)
Lives here naturally · Countries and seas named by a scientific source
Countries where the IUCN lists common cuckoos as breeding birds (Europe and Asia, from Ireland and Portugal to Japan) or as resident, which includes the African countries where many cuckoos spend the winter. Cuckoos live in only parts of many countries shown. Andorra, Gibraltar, Liechtenstein, Malta, Hong Kong and the Maldives are also listed but have no separate map shape. The IUCN also lists Bur
Places: Afghanistan, Albania, Armenia, Austria, Azerbaijan, Belarus, Belgium, Bhutan and 96 more places.
Source: iucn-red-list · checked October 2026
Sightings recorded · Records of wild sightings (GBIF)
Counts of GBIF records of wild observations (human and machine) and preserved specimens. Records include introduced populations, vagrants, escaped or released animals and misidentifications, so a country with records is not necessarily part of the native range.
Wild sightings have been recorded in Sweden, Netherlands, France, Denmark, UK, Germany, Spain, Norway and 125 more places.
Source: gbif · checked October 2026
Range maps show where scientists say an animal lives, often country by country. An animal may live in only part of a country shown, and sightings records can include animals that wandered far from home.
Hairy caterpillars
Cuckoos eat insects.
They really like hairy caterpillars.
Common cuckoos eat mostly insects. The RSPB says they especially like hairy caterpillars. They also eat spiders and snails, and only rarely fruit.
Young cuckoos are fed by their foster parents, which are usually small insect-eating songbirds such as pipits, warblers and wagtails. More than 100 kinds of birds have been recorded raising young cuckoos.
The IUCN assessment lists insects, spiders and snails, and rarely fruit, in the diet; the RSPB describes insects, especially hairy caterpillars.
The IUCN text links declines in northern Europe to the intensification of agriculture, which leaves fewer insects and fewer hosts (Erritzøe et al. 2012), and it lists the hosts as many insectivorous songbirds.
Did you know?
Cuckoo chicks are raised by other birds.
Cuckoos never build nests. Foster parents such as meadow pipits raise their chicks.
An obligate brood parasite with more than 100 recorded host species (IUCN).
A bird that looks like a hawk
A flying cuckoo looks a bit like a hawk.
It has long, pointed wings and a long tail.
With its long tail, pointed wings and barred belly, a cuckoo can look a little like a small bird of prey such as a sparrowhawk. Its legs are yellow.
Only the male makes the famous cuck-oo call. The female makes a quite different, bubbling sound. A cuckoo's egg is about 22 by 16 millimeters and weighs about 3.2 grams.
The RSPB compares the cuckoo's sleek, long-tailed, pointed-winged shape to a kestrel or sparrowhawk and notes yellow legs and a yellow-and-black bill; it adds that only males give the 'cuck-oo' call, while females make a bubbling sound.
The BTO gives typical egg measurements of 22 by 16 millimeters and a mass of 3.2 grams, and describes the chicks as altricial and naked at hatching.
Raised by foster parents
The mother cuckoo does not build a nest.
She lays each egg in another bird's nest. That bird keeps the egg warm and feeds the cuckoo chick.
Cuckoos are brood parasites: they never build a nest or raise their own young. A female finds the nest of another bird, takes out one of its eggs and lays her own egg in its place. In one season she may lay 12 to 22 eggs, each in a different nest. In Britain, meadow pipit nests are a favorite.
The foster parents keep the egg warm, and the cuckoo chick hatches after about 12 days. It soon takes all the food the foster parents bring and grows much bigger than them. It leaves the nest at 17 to 21 days old and is fed for about two more weeks.
The IUCN text calls the species a brood parasite with over 100 recorded host species, mostly insectivorous songbirds such as flycatchers, chats, warblers, pipits, wagtails and buntings; in north-west Europe it breeds between May and June. The RSPB says a female removes one host egg and lays hers in its place, lays 12 to 22 eggs a season in different nests, and tends to choose the same host species that raised her, with meadow pipits particularly favored in Britain.
The BTO gives host incubation of 11 to 13 days (the RSPB says 12), naked, altricial chicks, fledging at 17 to 21 days, breeding typically from two years old, and a longest-lived ringed bird of 6 years, 11 months. The RSPB adds that the young cuckoo takes all the food the hosts bring and is fed for a further two weeks after leaving the nest.
Long journeys to Africa
Grown-up cuckoos leave early in summer.
The young cuckoos fly to Africa later.
Because other birds raise their young, adult cuckoos can leave early. In Britain most adults leave in June, and the young cuckoos follow later, once they are fully grown.
Since 2011, scientists at the British Trust for Ornithology have put small satellite tags on cuckoos. They found that British cuckoos fly south by different routes, some through Italy and some farther west, but all spend the winter in the same part of central Africa, in and near the Congo rainforest, and all come back by the western route in spring.
The RSPB notes that adults, freed from parental care, mostly leave Britain in June, while juveniles leave later once fledged; the BTO says males can leave as early as the first week of June.
The BTO's Cuckoo Tracking Project, running since 2011, showed for the first time the routes and wintering areas of British cuckoos: some migrate south-east via Italy and others take a western route, yet all winter in the same part of central Africa and all return via the western route in spring. The BTO has linked the different routes to the declines in southern Britain and is studying how the return journey through West Africa depends on the rains of the Inter-Tropical Convergence Zone.
Did you know?
Only the father cuckoo says cuck-oo.
Only male cuckoos make the cuck-oo call; females make a bubbling sound.
The two-note 'cuck-oo' is given by males only; females give a bubbling call (RSPB).
Listen to a cuckoo
Listen to the sound at the start of this page.
It is a real cuckoo calling cuck-oo in England.
At the start of this page you can play a real recording of a common cuckoo. Aubrey John Williams recorded it on 13 May 1979 at Frensham Great Pond in Surrey, England, and it is kept in the British Library's collection of wildlife recordings.
The RSPB says most people recognize the call, because it spells out the bird's name. Remember: only males call cuck-oo.
The recording on this page (Wikimedia Commons, from the British Library's digital collections) was made by the sound recordist Aubrey John Williams on 13 May 1979 at Frensham Great Pond, Surrey, England, and is described as the song of a common cuckoo.
The RSPB notes that only males give the two-note 'cuck-oo', which spells out the name, while females make a bubbling call; the BTO calls it the bird's familiar two-note call, which has been lost from many former haunts in Britain.
Did you know?
Scientists follow cuckoos with tiny tags.
Since 2011, satellite tags have shown that British cuckoos spend the winter in central Africa.
The BTO Cuckoo Tracking Project (since 2011) revealed shared central African wintering areas and a western spring route (BTO).
Least concern, but fewer in Britain
There are millions of cuckoos in the world.
But in Britain there are fewer than before.
Worldwide, the common cuckoo is listed as least concern, and its numbers seem steady overall. In western Europe, though, cuckoos have declined. In the United Kingdom, numbers fell by about a third between 1995 and 2024, and the cuckoo is on the UK's Red List.
Scientists link the declines to farming that leaves fewer insects and fewer host birds, and to changes in the timing of spring, which can leave cuckoos arriving after their hosts have started nesting.
BirdLife International assessed Cuculus canorus as Least Concern for the IUCN Red List (assessed 14 May 2024, published 2024). Europe's 8.64 to 13.6 million mature individuals (BirdLife International 2021), about a quarter of the range, give a very preliminary global estimate of 34.6 to 54.4 million; western European declines and eastern stability make the global trend stable over three generations (11.37 years). Threats named are agricultural intensification and climate change, as short-distance-migrant hosts have advanced their arrival more than cuckoos, so nesting times no longer match (Erritzøe et al. 2012); the species was found in three of seven trade datasets (Donald et al. 2024).
The BTO gives about 18,000 UK pairs (2016) and a 33% decrease from 1995 to 2024, steepest in southern Britain; the RSPB lists it as Red in the 2021 UK Conservation Status Report.
IUCN Red List
How is the common cuckoo doing in the wild?
- Least Concern (this animal)
- Near Threatened
- Vulnerable
- Endangered
- Critically Endangered
- Extinct in the Wild
- Extinct
Least Concern
Not at risk of disappearing from the wild right now.
Amazing facts
-
Only the father cuckoo says cuck-oo.
Only male cuckoos make the cuck-oo call; females make a bubbling sound.
The two-note 'cuck-oo' is given by males only; females give a bubbling call (RSPB).
-
Cuckoo chicks are raised by other birds.
Cuckoos never build nests. Foster parents such as meadow pipits raise their chicks.
An obligate brood parasite with more than 100 recorded host species (IUCN).
-
Young cuckoos fly to Africa later than the grown-ups.
Adult cuckoos leave Britain in June; the young follow later.
Adults mostly leave Britain in June; juveniles depart later once fledged (RSPB).
-
Scientists follow cuckoos with tiny tags.
Since 2011, satellite tags have shown that British cuckoos spend the winter in central Africa.
The BTO Cuckoo Tracking Project (since 2011) revealed shared central African wintering areas and a western spring route (BTO).
Words to know
- brood parasite
- an animal that has another kind of animal raise its young
- host
- the bird whose nest a cuckoo uses and which raises the cuckoo chick
- migrate
- to move from one place to another as the seasons change
- satellite tag
- a tiny device that sends an animal's location to scientists
- foster parent
- an animal or person who raises young that are not their own
Discovery challenge
-
Who keeps a cuckoo's egg warm?
Who looks after a cuckoo's egg and chick?
Which birds incubate the cuckoo's egg and rear the chick?
- Another kind of bird
- The cuckoo's own parents
- Nobody: it hatches alone
Show the answer
Another kind of bird
Another bird does!
Host birds, such as meadow pipits or warblers, keep the egg warm and feed the chick.
Host species, mostly insectivorous songbirds (IUCN; RSPB).
-
Which cuckoo calls cuck-oo?
Which cuckoos make the cuck-oo call?
Which sex gives the two-note 'cuck-oo' call?
- Only the males
- Only the females
- Only the chicks
Show the answer
Only the males
The fathers!
Only males call cuck-oo; females make a bubbling sound.
Males; females give a bubbling call (RSPB).
-
Where do British cuckoos go in winter?
Where do cuckoos from Britain spend the winter?
Where did satellite tracking show British cuckoos winter?
- Central Africa
- The Arctic
- Australia
Show the answer
Central Africa
In Africa!
In central Africa, in and near the Congo rainforest.
All tracked birds wintered in the same part of central Africa (BTO).
-
What does a cuckoo like to eat?
What food do cuckoos especially like?
Which prey does the RSPB single out in the cuckoo's diet?
- Hairy caterpillars
- Fish
- Seeds
Show the answer
Hairy caterpillars
Hairy caterpillars!
Insects, especially hairy caterpillars, plus spiders and snails.
Insects, especially hairy caterpillars (RSPB); also spiders and snails (IUCN).
Places where you might see it
-
Watch
Country
United Kingdom
The United Kingdom, or UK, lies on islands off the northwest coast of Europe. It is made up of four parts, England, Scotland, Wales and Northern Ireland, and about 69.5 million people live there. Its capital is London.
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Watch
Country
Russia
Russia is the largest country in the world. It stretches across eastern Europe and all of northern Asia, through 11 time zones, from the Baltic Sea to the Pacific Ocean. It has frozen tundra, huge forests, Lake Baikal and the big cities of Moscow and Saint Petersburg.
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Watch
Country
Democratic Republic of the Congo
The Democratic Republic of the Congo, or DR Congo, is the second-largest country in Africa. The mighty Congo River curves through its rainforests, volcanoes rise in the east, and its capital, Kinshasa, is a center of music, fashion and popular culture.
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For parents & teachers
What children will learn
- Explain what a brood parasite is and how cuckoos use host birds.
- Trace the cuckoo's migration between Europe and Africa.
- Describe how male and female cuckoos sound different.
- Name reasons why cuckoos have declined in parts of Europe.
Recommended ages: 3 to 17 · About 15 minutes
Talk about it
- How might a young cuckoo find its way to Africa without its parents?
- Why might fewer insects affect both cuckoos and their host birds?
- What can satellite tags teach scientists that watching birds cannot?
Try at home or in class
- Map a journey: on a world map, draw a route from Britain to central Africa and back, and measure roughly how far it is.
- Egg size: draw an egg 22 by 16 millimeters and compare it with a chicken's egg from the kitchen.
Key vocabulary: brood parasite, host, migrate, satellite tag, foster parent
Where these facts come from
- GBIF Backbone Taxonomy and GBIF Occurrence Search , Global Biodiversity Information Facility (CC0 1.0 (backbone); occurrence counts are facts derived from records under CC0, CC BY and CC BY-NC)
- Wikidata , Wikimedia Foundation (CC0 1.0)
- The IUCN Red List of Threatened Species , International Union for Conservation of Nature (IUCN terms of use (no redistribution of Red List data or range maps))
- Cuculus canorus (BirdLife International, assessed 14 May 2024, published 2024) , IUCN Red List of Threatened Species
- Cuculus canorus: justification, population, habitat, threats and trade text , IUCN Red List of Threatened Species
- Cuculus canorus: IUCN Red List global assessment record (BirdLife International 2024), IUCN checklist on GBIF , GBIF
- Cuckoo , RSPB
- Cuckoo (BirdFacts) , British Trust for Ornithology
- Cuckoo Tracking Project , British Trust for Ornithology
- File:Cuckoo in Surrey, England.jpg (Andy Morffew, 7 May 2021) , Wikimedia Commons
- File:Common Cuckoo (Cuculus canorus) (W1CDR0001463 BD1).ogg (British Library; recordist Aubrey John Williams, 13 May 1979) , Wikimedia Commons
- Wikimedia Commons , Wikimedia Foundation (Per file: Public domain, CC0, CC BY or CC BY-SA only (credited on each page))
Checked, not yet human-reviewed. Last updated November 1, 2026. Spotted a mistake? Tell us.