In April, we hear the song of the cuckoo everywhere in the countryside. It is the birdsong that is the easiest to recognise, but the bird does not show itself as easily as it makes itself heard.
As is well-known, the female lays her eggs in another bird’s nest and never looks after her young. She can place between eight and 25 eggs in other birds’ nests at a rate of one a day, one egg per nest, always in the afternoon.
What is less well-known is that these birds produce eggs that imitate the colour of those of their victims, and that this plagiarism runs in the family. From mother to daughter, whole family lines of cuckoos specialise in imitating the eggs of a certain bird that will be their preferred target.
When the young cuckoo is born, after 11-13 days of incubation, it throws the other eggs and chicks out of the nest so as to be better fed by its adoptive parents.
Curiously, the young cuckoo, which has never seen its parents, is able to work out its August migration route on its own; then, the next spring, regular as a cuckoo clock, it will be back again to announce the coming of warmer days.
In France, if you have money on you when you hear the first cuckoo of the year, it is said to be a prediction of wealth.
The common (grey) cuckoo often eats prickly caterpillars, such as the pine processionary, which ravage conifers. The bird is undeniably useful: with global warming, processionaries are coming further north and invading areas that were free from them in the past.
When a cuckoo swallows a hairy caterpillar, its prickly hairs stick into the bird’s gizzard (the equivalent of our stomach) and end up by lining it completely. At that point, the bird spits out the whole skin of its stomach, which comes out looking like fur. Once it has done that, the gluttonous bird is ready again to stuff itself with itchy bugs, and can repeat the exercise as often as necessary.
What’s in a name? The name of the cuckoo has helped language experts better understand the pronunciation of Latin. It comes from the Latin cuculus, and was meant to imitate the sound of the bird’s cry. That tells us that the Romans pronounced their U’s as an “ou”, like the soft, rounded sound the bird makes (as in its French name,
“Coucou” is used in France as an exclamation meaning “Hi there!” or “Cooey!” Faire un petit coucou can mean to call in to say hello to someone, or, sometimes, to wave at someone.