When I speak of the cuckoo, I do not speak of jewelled marvels like this one:
(Male Asian Emerald Cuckoo)
There are many such cuckoos, each weirder, brighter and more extravagantly-tailed than the last. Our business is not with them. Our business is only with the cuckoo from which all cuckoos take their name: the common cuckoo, cuculus canorus. Once known as the European cuckoo, this species spends its summers in Europe and Asia and its winters in Africa. Like the hoopoe, the chiffchaff and the peewit, it is named for the sound it makes – and the other cuckoos, although they have different songs, are named for it too.
If ever there is a month to consider the cuckoo, it is this one. In his poem ‘To a Cuckoo’, William Wordsworth hails the bird as the ‘darling of the spring’ and throughout Europe, the first hearing of the cuckoo – usually in March, sometimes in April – marks the beginning of the season. Cuckoos are elusive creatures and tend to stay out of human sight, but their two-note call can be heard until the end of summer.
Here is a female of the species:
I like her striped chest and her orange eye, but I admit that she is drab compared to most cuckoo species. (The male common cuckoo looks very similar, but without the pink tinge to his chest.) Do not be fooled: her conservative appearance conceals some outrageous behaviour.
The common cuckoo is a brood parasite. This means that the female lays her egg in the nest of another bird (called the host bird) and flies off, leaving the host to raise and feed her chick. In Northern Europe, the most common hosts for the cuckoo are the dunnock, the meadow pipit and the Eurasian reed warbler. I will use the reed warbler as my example host.
The female cuckoo waits until the reed warbler has left her nest before she swoops in to lay her egg. But reed warblers are not stupid. If a warbler has laid four eggs and comes back to find five, she might realise that something is up. So the female cuckoo often knocks one of the warbler’s eggs out the nest before laying her own and flying away. She does not hang around: the whole thing takes about 10 seconds. She may eat the discarded warbler egg for good measure.
Sometimes, the reed warbler will notice that there is an impostor egg in her nest. If this happens, she might push the impostor out or abandon the nest entirely, including her own eggs. Most of the time, however, she will be oblivious, and incubate the cuckoo egg alongside her own.
Cuckoos have evolved so that their eggs resemble the eggs of the particular host species most convenient for them to use. As a result, different kinds of common cuckoo lay different-coloured eggs.
In the photo above, each compartment contains one cuckoo egg and several warbler eggs. You can see how alike they are in colour and patterning. The cuckoo egg is rather larger than the others in its group, but this does not matter: though reed warblers are sensitive to colour, they do not notice differences in size.
Usually, the cuckoo chick hatches before the warblers, at which point the newborn cuckoo will throw the unhatched warbler eggs out of the nest. If the warblers happen to have hatched before the cuckoo, the cuckoo will push the live warbler chicks out the nest with equal ruthlessness. By the time the cuckoo chick is two weeks old, it will be three times the size of the parent warblers who are feeding it.
(Tiny reed warbler feeding enormous cuckoo chick. The warbler has no idea that it is not feeding its own child)
The baby cuckoo calls loudly enough to fool the mother and father warblers into thinking they are caring for a whole brood rather than a single chick. As a result, they will make extra effort to gather food. Essentially, the cuckoo has it all figured out.
After about three weeks, the cuckoo will be ready to leave the nest and fend for itself. Its adopted parents will never know that they raised a chick not their own.
As you might expect, the cuckoo has received a lot of criticism for this behaviour. Chaucer calls the bird ‘ever unnatural’. This is in The Parliament of Fowls, a long poem in which the Chaucer-character watches all the different kinds of birds choosing their mates on St Valentine’s Day. Other Chaucerian bird descriptions from this poem that I particularly enjoy include ‘the false lapwing, full of trickery’, ‘the starling, that can betray secrets’, ‘the vigilant goose’, ‘the popinjay, full of wantoness’ and ‘the drake, destroyer of his own kind’.
The cuckoo has an implicit presence in two of Chaucer’s Canterbury Tales (the Merchant’s and the Miller’s), both of which involve a husband becoming a cuckold. ‘Cuckold’ is the word for a man who’s been ‘cuckooed’ – in other words, another man has come along to have sex with his wife, and he may end up raising a child not his own. The earliest known English usage of ‘cuckold’ is in a poem named after two other birds, The Owl and the Nightingale, which dates from the 12th or 13th century.
Because we are humans and not reed warblers, meadow pipits or dunnocks, we more often celebrate the cuckoo for the good it brings us than the harm it brings its fellow birds. Long before Wordsworth, poets were praising the cuckoo as a bringer of spring and a symbol of summer. The 13th-century song ‘Sumer Is Icumen In’ has a chorus of ‘Sing cuccu nu, sing cuccu/ Sing cuccu, sing cuccu nu!’, and places the cuckoo’s song alongside all manner of summery pastoral activity. Seeds grow, lambs bleat, stags fart (‘bucke verteth’, in Middle English) – that kind of thing. You can find the full text – in the original and in translation – here.
(manuscript of ‘Sumer Is Icumen In’, mid-13th century, owned by the British Library)
Here is a particularly jolly arrangement of the song:
Slightly less jolly and rather more strange is the performance of the song at the 1972 Munich Olympic Games Opening Ceremony:
In his poem ‘Short Ode on the Cuckoo’, WH Auden reminds us of what ought to count against the bird:
Compared with arias by the great performers
such as the merle, your two-note act is kid-stuff:
our most hardened crooks are sincerely shocked by
your nesting habits.
In reality, these things count for nothing. Like Wordsworth, who calls the cuckoo ‘an invisible thing… a mystery’ transforming the earth into ‘an insubstantial, faery place’, Auden concludes that our connection to the cuckoo defies the logic of the modern age.
Science, Aesthetics, Ethics, may huff and puff but they
cannot extinguish your magic: you marvel
the commuter as you wondered the savage.
Hence, in my diary,
where I normally enter nothing but social
engagements and, lately, the death of friends, I
scribble year after year when I first hear you,
of a holy moment.
All images via Wikimedia Commons, unless otherwise specified.
Hannah Rosefield likes writing about books and birds. She lives in London and tweets.