Hard facts of life for birds, bees and butterflies - Telegraph

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It was true that the doggedly hardy spring flowers - the daffodils, the bluebells and the tulips - had braved the temperatures and appeared almost on schedule, as had the magnolias, camellias and copious spring blossoms. But on the allotment, the early sowings of peas, parsnips and potatoes had obstinately refused to show their heads.

With the cricket season seeming to start ever earlier, I spent a day last week at Kennington Oval. Despite the sunshine, the long-suffering spectators were muffled in the scarves, sweaters and woolly hats you usually see at football or rugby matches.

The players, too, had either put on the pounds over the winter or were sporting several layers of insulation beneath their pullovers (no sign, at county level, of the high-tech fleeces recently unveiled by England). They are allowed to leave the field for rain, but not biting cold.

But suddenly, all this is about to change. If the forecasters (and my barometer) are to be believed, you should have woken this morning to a blue sky and temperatures that by the end of the day will have soared to Mediterranean levels: time, you'd think, to get out the garden chairs and clean up the barbecue.

Yet without wishing to spoil the party, I must point out the clouds on the horizon. It is not just that, after today's sunshine, the rain will be back for a spell.

The problem is that alongside the promise of balmier weather has come a spate of warnings from scientists and environmentalists, telling us of threats to many of the elements that make summer so pleasurable.

This week, we took our grandchildren to the delightful butterfly exhibition at the Natural History Museum in London. First, we went through a maze packed with games and gizmos that explain in a child-friendly way how butterflies come into being, and the contribution they make to the natural world.

Then we were admitted to a super-heated tent, in which some of the world's most exotic species were silently flitting between flowers and plants specially grown to attract them - even if some preferred the attractions of their visitors' coats, and had to be brushed or shaken off before we could emerge into the chilly fresh air.

There was, though, a disturbing subtext to the display. Captions warned us that some of the most spectacular butterflies are threatened by the changing climate and modern agricultural practices.

That message was underlined later in the week when the Butterfly Conservation Trust claimed that many of the species which characterise our summers have declined to dangerously low levels.

The trouble is not so much global warming as drenching, specifically, last year's abysmally wet summer.

Butterflies, like cricketers, do not go out in the rain. This means that they cannot get to the plants they feed on.

Moreover, it dampens their inclination and ability to breed. Some of our favourite species could disappear - although I notice that the cabbage white, that scourge of vegetable gardeners, is not on the list of those under threat.

The trust says that with another wet summer - or a drought, which would diminish the number of flowers that provide their food - we could be facing a "butterfly catastrophe".

It is not necessary to go along with that hyperbole to regret any harm done to these colourful creatures, whose elegant progress from flower to flower provides the perfect backdrop to a lazy summer afternoon.

But butterflies are not the only garden visitors in danger. Earlier in the week came a report warning of another potential ecological calamity.

The Royal Society for the Protection of Birds said that, according to its periodic surveys, there has been a startlingly rapid decline in the numbers of certain species, especially those that migrate to Europe from Africa.

The number of cuckoos, formerly infallible harbingers of spring, has gone down by more than half in the past 40 years, and there are some parts of the country where they are scarcely heard. The nightingale has fared even worse, declining by two thirds since 1980, as has the skylark, Shelley's "blithe spirit".

Some of our most familiar garden birds are also dwindling noticeably. The sparrow, formerly the chirpy symbol of Cockney London, is a much less frequent visitor to my inner-city garden than when I moved here 40 years ago. And it is not nearly as common as it was to see flocks of croaking starlings congregating in the treetops in the evening.

The changing climate is only one of the reasons why some birds do not choose to spend their summers here any more. Another is the altered nature of farming. The growing use of insecticides deprives them of their staple foods, and the destruction of hedgerows means that there are fewer places to nest and shelter.

Then there are the bees. While we do not welcome these pesky insects if they disturb our picnics and barbecues, we recognise that they perform an irreplaceable service in transferring the pollen that makes summer flowers bloom so magnificently - as well as donating honey for the picnics that we enjoy while lounging among them.

Bees are threatened on two main fronts: by a parasite known as varroa destructor, and by the mysterious scourge of colony collapse disorder, which has spread to Europe from North America. Affected swarms simply abandon their hives and take themselves off to die.

The British Beekepers' Association has said that more than 11 per cent of hives were lost last year.

Unless something is done, there could be no honeybees left by 2018. "We're facing calamitous results," admitted their spokesman.

It is good to be alerted to these threats, even though it might be inevitable that some species of birds, bees and butterflies will disappear: it has happened throughout history. Yet we should not let the alarming prospect spoil our enjoyment of the year's first summery weekend.

For my part, I shall be putting up the beanpoles on the allotment and planting out the runner beans that I have been raising in the back bedroom for the past few weeks; we shall also be reaping our first substantial harvest of asparagus.

I have taken down from a shelf, too, the 2008 edition of the National Gardens Scheme's Yellow Book, which lists garden openings across the country in aid of charities.

The garden visiting season is just getting into its stride. Hundreds of cherished and cosseted plots, large and small, are listed as being open on this last weekend in April.

It is a bit early for butterflies; but visit one or two of them and enjoy the birds, the bees and the blossoms while you can.

via telegraph.co.uk