18.7 C
Thursday, July 18, 2024
EnvironmentNature Studies April 24

Nature Studies April 24

An incomer’s discovery of the natural world in the Westcountry

I sometimes think that the old adage that one swallow doesn’t make a summer, wise though it may be, isn’t actually true. Certainly, my own first glimpse in mid-April of that small and streamlined bundle of navy-blue feathers, on its return from wintering in South Africa, makes my heart leap, for I know it means the warm times are nearly here. It’s a feeling of elation, never better encapsulated than by Gilbert White, the 18th century parson-naturalist and author of The Natural History of Selborne, who so adored swallows and their annual arrival in his Hampshire village that he made his diary entry for April 13 1768 just two words, plus three exclamation marks: Hirundo domestica!!! (Using the then-current scientific name for the bird.)

So I personally feel that one swallow, or certainly the first one, does in some way make a summer; and I imagine many people share my view that the birds’ annual return, just about now, is one of the wildlife highlights of the year. Certainly, it has been celebrated for millennia—it was a favourite event in Ancient Greece—and it is only equalled by the similarly exhilarating sight, a month later, of the dark shape of the first swift, arcing through the sky. (Swifts are not related to swallows but they have the same sort of streamlined outline because they occupy the same ecological niche, as high-speed aerial insect-chasers.)

We particularly enjoy the arrivals of these two because their returns are the most visible of all our summer migrant birds, which come to us to breed after an African winter. When swallows and swifts are swooping around, you can’t miss them. But there are nearly fifty more species of summer visitors, including some of our most celebrated birds, such as the cuckoo, the nightingale and the turtle dove, and some which are less famous but dearly loved, such as the chiffchaff, the willow warbler and my own favourite, the spotted flycatcher. They’re all part of a great aerial river of millions of these small creatures. which every spring make gigantic journeys from the African continent to breed in Britain and the rest of Europe, before returning south for the winter. It’s an incredible feat, an incredible natural event. But it’s running into serious trouble.

Nearly twenty years ago ornithologists started to realise that our summer migrants were falling in numbers; and not only that, but they were declining at a faster rate than related species which were all-year-round residents. Since then, the declines have in some cases become critical. The worst is the turtle dove, which has declined by 98 per cent and is extinct in much of Britain, followed by the nightingale, whose numbers have dropped by 93 per cent, and the spotted flycatcher with a fall of 90 per cent. The cuckoo has dropped in numbers by 78 per cent—when did you last hear one?—while the swift has dropped by 58 per cent. Even the swallow, which for a long time seemed to be holding its own, has dropped by 16 per cent.

In recent years a huge amount of research has been devoted to migrants, and enormous advances have been made in electronic tracking—that is, following the birds by fitting them with miniaturised tracking devices. We now know exactly whereabouts in Africa many of our summer visitors spend the winter, and how they get there (for example, our cuckoos nearly all go to the Republic of the Congo). But a summary of the research published last year by the British Trust for Ornithology and others admitted that the new knowledge has not yet thrown any light on why so many of the species are declining. Is it problems in Britain? Problems on their African wintering grounds? Or problems on the enormous journeys in between? We still do not know. Two possible causes have been highlighted: insect decline, the scale of which is only just being recognised, and overhunting of the birds on their odysseys through Europe. But there is as yet no proof that these are indeed the causes.

What we do know is that the declines are continuing. And now the turtle dove no longer returns to much of our land, and nor does the nightingale, and nor does the cuckoo. And in an increasing number of places, the swift no longer returns. Might one day the English springtime come, hitherto unimaginable, but perhaps not all that far off, when the swallow is no longer part of it?

Previous article
Next article

Exclusive content

- Advertisement -spot_img

Latest articles

More article

- Advertisement -spot_img