Cuckoo
The Common Cuckoo, or simply Cuckoo in the UK, is a member of the Cuculiformes or cuckoo order of birds. The Common Cuckoo’s name is derived from the Latin cuculus (the cuckoo) and canorus (melodious, from canere, meaning to sing). The cuckoo family gets its common name and genus name from onomatopoeia for the call of the male Common Cuckoo.
The Cuckoo is around 13 inches long from bill to tail with a tail of 5.1 to 5.9 inches and a wingspan of 22 to 24 inches. It has a greyish, slender body and long tail, similar to a Sparrowhawk in flight, where the wingbeats are regular. During the breeding season, the Cuckoo will often settle on an open perch with drooped wings and raised tail.
All adult males are slate-grey and the grey throat extends well down the bird's breast with a sharp demarcation to the barred underparts. The iris, orbital ring, the base of the bill and feet are yellow. Grey adult females have a pinkish-buff or buff background to the barring and neck sides and sometimes small rufous spots on the median and greater coverts and the outer webs of the secondary feathers. Rufous morph adult females have reddish-brown upperparts with dark grey or black bars.
The male Cuckoo's song is usually given from an open perch. During the breeding season the male typically gives the well-known vocalisation with intervals of 1 to 1.5 seconds and in groups of 10 to 20 with a rest of a few seconds between groups. The female has a loud bubbling call. The wings are drooped when the male Cuckoo is calling intensely and when in the vicinity of a potential female and it often wags its tail from side to side or the body may pivot from side to side.
The Cuckoo is essentially a bird of open land and a widespread summer migrant to Europe and Asia. Birds arrive in Europe in April and leave between June and September for their wintering grounds in Africa. Between 1995 and 2015, the distribution of the Cuckoo within the UK has shifted towards the north with a decline by 69% in England but an increase by 33% in Scotland.
The Cuckoo is a brood parasite, meaning that it lays its eggs in the nests of other birds. A female may visit up to 50 nests during a breeding season. More than 100 host species have been recorded: Meadow Pipit, Dunnock and Reed Warbler are the most common hosts in northern Europe; Garden Warbler, Meadow Pipit, Pied Wagtail and Robin in central Europe; Brambling and Common Redstart in Finland; and Great Reed Warbler in Hungary.
Female Cuckoos are divided into gentes i.e. groups of females favouring a particular host species' nest and laying eggs that match those of that species in colour and pattern. As the Cuckoo evolves to lay eggs that better imitate the host's eggs, the host species adapts and is more able to distinguish the Cuckoo egg.
Research has shown that the female Cuckoo is able to keep its egg inside its body for an extra 24 hours before laying it in a host's nest. This means the Cuckoo chick can hatch before the host's chicks do and then it can eject the unhatched eggs from the nest.
The Cuckoo chick hatches after 11 to 13 days and it methodically evicts all host eggs or chicks from the nest. It is a much larger bird than its host and it needs to monopolize the food supplied by the parents. The chick will roll the other eggs out of the nest by pushing them with its back over the edge. If the host's eggs hatch before the Cuckoo's, the Cuckoo chick will push the other chicks out of the nest in a similar way. At 14 days old, the Cuckoo chick is about 3 times the size of an adult Reed Warbler. Cuckoo chicks fledge about 17 to 21 days after hatching compared to 12 to 13 days for the Reed Warbler.
The Cuckoo's diet consists of insects, with hairy caterpillars which are distasteful to many birds, being a specialty of preference. It will also occasionally eat eggs and chicks.
Date: 3rd May 2022
Location: RSPB Canvey Wick, Canvey Island, Essex
The Cuckoo is around 13 inches long from bill to tail with a tail of 5.1 to 5.9 inches and a wingspan of 22 to 24 inches. It has a greyish, slender body and long tail, similar to a Sparrowhawk in flight, where the wingbeats are regular. During the breeding season, the Cuckoo will often settle on an open perch with drooped wings and raised tail.
All adult males are slate-grey and the grey throat extends well down the bird's breast with a sharp demarcation to the barred underparts. The iris, orbital ring, the base of the bill and feet are yellow. Grey adult females have a pinkish-buff or buff background to the barring and neck sides and sometimes small rufous spots on the median and greater coverts and the outer webs of the secondary feathers. Rufous morph adult females have reddish-brown upperparts with dark grey or black bars.
The male Cuckoo's song is usually given from an open perch. During the breeding season the male typically gives the well-known vocalisation with intervals of 1 to 1.5 seconds and in groups of 10 to 20 with a rest of a few seconds between groups. The female has a loud bubbling call. The wings are drooped when the male Cuckoo is calling intensely and when in the vicinity of a potential female and it often wags its tail from side to side or the body may pivot from side to side.
The Cuckoo is essentially a bird of open land and a widespread summer migrant to Europe and Asia. Birds arrive in Europe in April and leave between June and September for their wintering grounds in Africa. Between 1995 and 2015, the distribution of the Cuckoo within the UK has shifted towards the north with a decline by 69% in England but an increase by 33% in Scotland.
The Cuckoo is a brood parasite, meaning that it lays its eggs in the nests of other birds. A female may visit up to 50 nests during a breeding season. More than 100 host species have been recorded: Meadow Pipit, Dunnock and Reed Warbler are the most common hosts in northern Europe; Garden Warbler, Meadow Pipit, Pied Wagtail and Robin in central Europe; Brambling and Common Redstart in Finland; and Great Reed Warbler in Hungary.
Female Cuckoos are divided into gentes i.e. groups of females favouring a particular host species' nest and laying eggs that match those of that species in colour and pattern. As the Cuckoo evolves to lay eggs that better imitate the host's eggs, the host species adapts and is more able to distinguish the Cuckoo egg.
Research has shown that the female Cuckoo is able to keep its egg inside its body for an extra 24 hours before laying it in a host's nest. This means the Cuckoo chick can hatch before the host's chicks do and then it can eject the unhatched eggs from the nest.
The Cuckoo chick hatches after 11 to 13 days and it methodically evicts all host eggs or chicks from the nest. It is a much larger bird than its host and it needs to monopolize the food supplied by the parents. The chick will roll the other eggs out of the nest by pushing them with its back over the edge. If the host's eggs hatch before the Cuckoo's, the Cuckoo chick will push the other chicks out of the nest in a similar way. At 14 days old, the Cuckoo chick is about 3 times the size of an adult Reed Warbler. Cuckoo chicks fledge about 17 to 21 days after hatching compared to 12 to 13 days for the Reed Warbler.
The Cuckoo's diet consists of insects, with hairy caterpillars which are distasteful to many birds, being a specialty of preference. It will also occasionally eat eggs and chicks.
Date: 3rd May 2022
Location: RSPB Canvey Wick, Canvey Island, Essex