Springwatch British Wildlife: Accompanies the BBC 2 TV series. Stephen Moss
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cuckoos lay their eggs in other birds’ nests, a strategy known as ‘brood parasitism’. Although this may seem rather bizarre, it clearly works: because she is free from the burden of having to raise a brood of chicks, which takes up a huge amount of time and energy, the female cuckoo is able to lay up to 20 eggs.
British cuckoos have three main host species: the reed warbler, meadow pipit and dunnock. A female cuckoo will lay her eggs in the nest of the species that raised her, but perhaps the most fascinating aspect of the cuckoo’s breeding behaviour is what happens after the chick hatches. Almost as soon as it is born, the baby cuckoo uses its amazing strength to throw out the other eggs in the nest. This means that the unfortunate host parents have only one chick to feed – but what a chick! Cuckoos grow larger than the parents themselves, whose work is cut out feeding this monster in their nest.
Whereas the cuckoo is undergoing a sharp decline, its fellow migrant, the nightjar, is currently doing rather well. As a species on the northern edge of its breeding range in Britain, it may even be benefiting from climate change, which has enabled it to shift its breeding range farther north. Better management of its heathland and forest habitat has also contributed to its success.
Nevertheless, the nightjar remains a tricky bird to see because of its nocturnal habits. Fine, warm evenings are best: just before dusk you may hear that characteristic mechanical noise known as ‘churring’, which, if you are lucky, will signal the appearance of a displaying bird against the darkening sky. Before the light begins to fade, look out for the prominent white patches towards the end of the nightjar’s wings, which the male uses to signal to the female. One way of getting better views of this elusive bird is to wave two white hankies around in the air, though of course you will risk being mistaken for a morris dancer!
Like owls, the nightjar has given rise to a large body of folklore: the name ‘goatsucker’ relates to the mistaken belief that these strange birds suckled goats. Another folk-name, ‘fern owl’, refers to the bird’s habitat of nesting among bracken.
Nightjars are almost impossible to see on the ground, as their plumage is camouflaged to blend in with their heathland habitat. But we are now learning a little more about both these species, thanks to our new-found ability to place tiny tracking devices on them before they undertake their journeys south.
©Dickie Duckett/FLPA
The cuckoo is far more often heard than seen, its celebrated call being linked with the coming of spring.
©Robert Canis/FLPA
The skylark may have a rather dull brown plumage but it has one of the most memorable songs of any British bird.
Some birds are inextricably linked with a particular kind of habitat: gannets with offshore islands, robins with gardens, and mallards with park ponds. But surely no bird is quite so closely tied to the place where it lives than the skylark. This is the quintessential farmland bird, spending most of its life in and around our arable fields.
And yet the skylark also lives in another, very different, habitat. Perhaps habitat is not quite the right word, for I am referring to the place the skylark has made its own: the sky. No other bird sings for quite so long, quite so persistently, and quite so high in the air. For hours on end, you can hear them, though sometimes you will struggle to see one, so high does it fly.
When your eyes finally settle on a tiny, dark speck, appearing to bounce up and down on an invisible piece of elastic, you may well doubt that it is a bird at all. Only when you watch as it drops like a stone, descending through the air on folded wings until it reaches the ground, is its identity confirmed. Should you then follow it to try to find its nest, you are unlikely to do so; skylarks are well known for landing some distance from their actual nest site, then running unseen through the long grass to reach it, thus foiling any watching predators.
Why skylarks choose to sing in the air for so long is the result of two factors: lack of competition (only the meadow and tree pipits even try to match it, and not for long), and an evolutionary arms race in which the birds that sang for longest, and most persistently, would win the attentions of the females. They then passed on their ability to their own offspring, and so the habit developed.
Recent studies have revealed another extraordinary aspect of the skylark’s behaviour. When confronted by a predator such as a merlin, experienced skylarks will sing louder, as if daring the falcon to do its worst and attack them. Less experienced birds often give in to their fear, stop singing and try to escape, at which point they are chased and caught by the merlin.
The skylark’s extraordinary song flight means that it has been justly celebrated in literature and music. The nineteenth-century poet George Meredith wrote his famous poem The Lark Ascending with the verse and rhythm mimicking the bird’s flight. The poem later inspired an equally memorable piece of music by the composer Ralph Vaughan Williams. Shelley, too, celebrated the bird in his famous ode To a Skylark with the opening lines ‘Hail to thee, blithe spirit! Bird thou never wert’.
Sadly, the song that inspired these great works of art is now rarely heard across great swathes of the British countryside. More than two million pairs of skylarks – about half the total numbers – have disappeared in the past 50 years because modern farming methods are incompatible with these birds’ complex needs.
Skylarks need a range of different ‘mini-habitats’ if they are to thrive. These include short, cropped grass, for feeding; patches of longer grass, where their nests will be safe from predators; and, most importantly of all, stubble fields packed with weed seeds, where they can feed during the winter months. Without this mosaic of habitats, numbers of skylarks are bound to continue to fall.
If we want to get our skylarks back, it seems we have no choice. We must, as a nation, make a wholesale shift away from industrial agriculture and move back to more mixed farming, which will inevitably mean more expensive food for us as consumers. It is either that or accept that this classic bird of the countryside will continue to decline, and perhaps one day even disappear.
©Mike Powles/FLPA
Skylarks nest on the ground, making them very vulnerable to farm machinery and attack by predators.
©Martin B Withers/FLPA
The male grey partridge has a distinctive horseshoe-shaped patch on its belly.
One group of birds has achieved fame not because of their beauty, or their unusual habits, but simply because they are good to eat. Britain’s game birds – those that are allowed to be shot for food at certain times of the year – come from a wide range of families, including ducks, such as wigeon, teal and mallard; waders (snipe and woodcock); and grouse. But the three most widespread and familiar species are those from the pheasant and partridge family: the common or ring-necked pheasant, and the grey and red-legged partridges.
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