Rural: Nature note

Cuckoos are back in action along the hedgerows. In the south of England the traditional date for their return from Africa is 16 April; this year they were about a week late, held back in their migration by cold winds from the north, but now they are once again hard at work, wrecking the nests of songbirds with their grotesque parasitic habits.

Let nobody think the cuckoo a benign harbinger of summer. Everything about it is sinister, from its menacing, hawk-like appearance, with its big head and powerful neck, to its steady, level flight. It is only the male which gives the familiar, two-note call: the female makes a completely different, bubbling chuckle as she settles on a particular area and searches for the nests of foster-parents - hedge sparrow, robin, meadow pipit and many others - in which to lay her eggs. Not only does she evict one of the small bird's eggs from every nest: she also lays her own on the same day, and, by some extraordinary biological mechanism, varies its colour from bluey green to red and grey, with different amounts of speckles, so that it more or less matches those of the fosterer.

The baby cuckoo hatches in only 12 or 13 days, and, being far bigger than its companions, ejects them from the nest one by one. The foster parents work desperately to feed their one giant infant, and in only three weeks it flies away. Since a single cuckoo can lay at least 20 eggs during the summer, her destructive capacity is immense.