Ask most people what they know about the Cuckoo, and the response probably would be that it is a bird that lays its eggs in other bird’s nests.
Absolutely true, but there is much more to this bird.
The bird’s scientific name is Cuculus Canorus. What a great name.
Imagine that this Cuckoo lays an egg in the nest of its host, usually a meadow pipit or reed warbler. The hen bird then removes an egg so that the number remains the same in the nest. The new egg, although slightly larger resembles the colour of the rest.
The practice of using other birds to incubate the egg and rear the young is known as brood parasitism.
Up until the early 20th century it was thought that the Cuckoo laid its egg on the ground, and transported it to the nest. Leading ornithologists and naturalists believed this. What people were observing was the cuckoo holding the stolen egg after it had been removed from the nest.
For some time the female Cuckoo had been observing the behaviour of the host bird. She knows exactly when the host is about to lie. This is crucial to the whole process.
When hatched, the Cuckoo chick, blind and naked and just a few hours old; immediately sets to work removing the original eggs or chicks from the nest. The tiny naked chick is programmed to do this. A wonder of nature. The female will lay about thirteen eggs in different nests.
The Cuckoo fledgling grows at a fantastic rate. Its call resembles a full nest of chicks so that the host birds respond to its begging sound. Even other birds passing will feed it responding to this call!
Remember that the young Cuckoo has never met its parents. By early September it leaves for equatorial or southern Africa. It arrives at the site of its ‘biological’ parents. It is not shown the way but is programmed by DNA to find its way. We just don’t know how they do it.
Surely this must be one of the wonders of nature. Just take a minute to think about it.
Cuckoos arrive here usually in April. Their arrival prompting calls to the editor of The Times. Their arrival, as with other migrating birds, coincides with the abundance of insects. They feed more or less exclusively on the hairy caterpillar, an insect poisonous to other creatures. Stomachs of Cuckoos are lined with the hairs of these caterpillars, and every so often they regurgitate the stomach lining.
Although not a hawk, it does resemble one in flight with its curved wings. Subsequently it is ‘mobbed’ by smaller birds. It seems to have a hawk’s body and pigeons head! What is the problem then? Well, as with many birds and animals, it is mainly down to habitat loss. And loss at a great rate.
The Cuckoo is in a chain.
If the caterpillar population crashes, the Cuckoo population crashes. If there is a reduction in the birds that the cuckoo uses as a host, it will suffer. Added to that, it often has to run the gauntlet of so called ‘hunters’ armed with the latest weaponry.
Over one hundred million migrating birds are killed whilst migrating across the Mediterranean. This number is arrived at via satellite studies.
Malta and Italy are the biggest culprits. It makes one sick. What do they get out of it?
The EU stated that they were going to tackle the problem. Did they? No.
Finally we have the Sahara. It is moving south at a fast rate, resulting in a longer journey without rest and water.
So when did YOU last hear a Cuckoo? I for one will certainly miss its call.
David Jones
Swansea Valley History Society 