Nature is a light that never goes out, but I’ll freely admit there are times of year when the flame burns low. The cuckoo, along with its song, is the bird that reinvigorates that light, for even the most unobservant will hear it and know it’s spring.
The cuckoo is about the size of a collared dove, with a body length of up to 36cm and wingspan as much as 60cm. In flight, the pointed wings and long tail give the appearance of a kestrel-sized bird of prey. The small bill soon clears up any confusion with more robustly beaked predators. Adult cuckoos are grey/blue headed, necked and backed. The undersides are white with dark horizontal barring, and their feet, eyes and base of lower bill all add a dash of yellow to the largely monochrome appearance. Both sexes are alike, though young birds appear brown backed.
Cuckoos are summer migrants, arriving from sub-Saharan Africa in April. Adult cuckoos leave as early as June on their return migration, though the young hang around for most of the summer. Do I need to describe the song of the cuckoo…? Probably not, but they also have a call that is described as guttural, a ‘Goch, che, che, che’ sound, often emitted in pursuit-flight, when chasing after a mate or scaring away a rival. The cuckoo is versatile in habitat choice, ranging from woodland, heathland, farmland and, of course, uplands. Though don’t expect to actually see them high up in the mountains – we’re talking about the valleys between the high peaks.
The cuckoo may be one of spring’s poster stars, yet its idiot-proof song belies a cheating, murderous existence. The reason for the adults’ early departure from our shores is the fact that they are a brood parasite – they lay their eggs in the nests of other species. These are normally meadow pipits, dunnocks or reed warblers. Interestingly, female cuckoos can be split into ‘gens’, or groups of birds whose eggs mimic one of the common host birds. For the cuckoos of the uplands, it’s the meadow pipit which will be the host species. The female cuckoo finds a potential nest, waits until the parents are out of sight, then ejects one of the original eggs and quickly lays one of her own. This will hatch in 12 days, and as the cuckoos are much bigger than their hosts the cuckoo chicks easily push out other young or eggs, leaving just the greedy cuckoo to be fed by its foster parents. They will do this for a couple of weeks after the bird has fledged. I’ve seen this a few times and it is strangely heartbreaking seeing such small parents busily
