Kitabı oku: «Nature Conservation»

1 Introduction: Where We Are Now
Wildlife in a crowded island

In his classic book, Nature Conservation in Britain (1969), Sir Dudley Stamp began with the world population. By the mid-1960s, wildlife shared the planet with 3,400 million human beings. Thirty years later that number had grown to 5,292 million. Today Asia alone holds most of the world population of the mid-1960s. In 2000, we broke the six billion mark. The United Nations forecast for 2050 is 9,833 million people; if so, in a single century the human population will have nearly trebled.

In Great Britain, by contrast, the population growth is slow. In 1921, nearly 43 million people lived on our island. In 1965, despite the postwar ‘baby boom’, the population had increased by only 19 per cent to 53 million. Today it stands at 57 million and is virtually static. Our population explosion happened early, in Victorian times. In the developing world, most people are young. In Britain we have an ageing population. Mr and Mrs Average will have 2.1 children and will live well into their seventies. If the size of the human population were all that mattered, the countryside and its wildlife would have been under remarkably little pressure in the twentieth century, except around a few cities, mainly in south-east England.

Even so, 57 million people is plenty on an island of only 230,000 square kilometres (88,780 square miles). It gives us an average population density of 3.6 persons per hectare in England, 1.36 in Wales and 0.65 in Scotland. We outnumber every wild mammal found in Britain, with the possible exception of the field vole. We outnumber the commonest wild bird by about five to one. If we all had a decent-sized garden, there would be no countryside.

The New Naturalist Board in 1966. From left to right: James Fisher, John Gilmour, Sir Julian Huxley, Sir Dudley Stamp and Eric Hosking. (Eric Hosking)

It is not the size of the human population so much as our changing ways of life that have created the pressure on our wildlife. Despite a near static population, another 4.4 million ‘homes’ are to be built over the next 20 years, at least half of them in the countryside. Apparently, this is because many people nowadays prefer to live on their own. Our devotion to the car has produced a bonanza of road building so that it can be hard to find a place where the traffic cannot be heard, and the stars shine in a dark sky. It has produced an American-style, road-centred landscape that was only starting to appear in the 1960s: flyovers, filling stations, shopping malls and multistorey car parks. Although roads are thin, they flatten a lot of wildlife sites. A clover-leaf motorway junction was built smack in the middle of Hook Common SSSI in Hampshire. Another motorway cut Aston Rowant National Nature Reserve in half (though zealous geologists promptly designated the road cutting). You get a wonderful view of bisected Kentish SSSIs from the M2.

Even so, if the rest of the countryside was still rich in wildlife, we could lose some of it to further our material convenience without losing any species. However, agricultural improvements, well under way by the 1960s, have transformed the old prewar mixed farms, with their acres of permanent pasture and miles of hedges, into prosperous modern arable units, or rye-grass-based milk factories. The reasons, which might seem inadequate now, made sense then. As a wise giant in Swift’s Gulliver’s Travels had observed, ‘whoever could make two ears of corn or two blades of grass to grow upon a spot of ground where only one grew before, would deserve better of mankind than the whole race of politicians put together’. We vastly exceeded that modest goal, but, essentially, the higher the unit production, the lower the value for wildlife. By the 1990s we had achieved what would once have seemed impossible: wheat fields with nothing left over for the wild birds to eat, or fields of grass with scarcely a single wild flower. Another crop that was starting to take over much of the poorer land in the 1960s was Sitka spruce. Forestry was once considered by many to be a friend to nature conservation. Unfortunately the industry went the same way as farming – trees were treated purely as a crop, like wheat – and so it lost the favourable reputation it is now struggling hard to regain. The nation could have fed itself without destroying important wildlife habitats, and the heavily subsidised home-grown trees scarcely dented Britain’s import bill for timber. The destruction of our wild places, it seems now, was unnecessary. If it had a single cause it was an airtight Ministry of Agriculture, the client ministry of the big farming unions and the agro-chemicals industry, but no one else. When the Ministry was finally put to sleep in the government reorganisation of June 2001, no one, least of all the farmers, had a good word to say for it. The officials of MAFF, it is said, were the most blinkered and obstinate in the entire civil service (ask anyone in a conservation agency – or for that matter, on a farm). They made a mess of everything, from BSE to ESAs. The chaos that engulfed the farming industry in the 1990s was the endgame of decades of preventable idiocy.

The New Naturalist Board in 2001. From left to right: Richard West, David Streeter, Derek Ratcliffe and Sarah Corbet. Max Walters is absent from the picture. (Debra Sellman)

A high-density human population makes every acre precious. As Dudley Stamp noted, ‘nature conservation must work out its own salvation in cramped conditions’. Good wildlife habitat, such as chalk grassland and heath, has been reduced to scraps within a predominantly arable or urban environment. Many of our nature reserves seem ridiculously small to visitors from large, continental countries like the United States. Yet the same visitors also marvel at how attractive much of our countryside still is, despite all the pressures upon it. The island scale of the British landscape means that small is often beautiful. Britain has an amazingly complex geology, producing variations in landforms and building stone within just a few miles. A traveller from London to Brighton passes over at least seven different landscapes on gravel, clay, greensand and chalk, past downs, heaths, woods and secluded lakes. The lowland agricultural landscape is a patchwork, and small nature reserves may be big enough to enclose some of the best examples of natural habitats. Even so, in the long run they may still be too small. Even quite large nature reserves cannot do much for wide-ranging, low-density species such as wildcats or golden eagles. Small reserves tend to lose more species than large ones. A famous example is the inability of Woodwalton Fen, a small, brick-shaped nature reserve in Cambridgeshire, to sustain a population of the large copper butterfly. The butterfly survived through the 1930s and 1940s, when the weather was kinder, but the reserve was just not big enough when the going got tough later on. Because they are small, British nature reserves tend to be highly planned, with various zones and prescriptions designed in effect to squeeze the maximum of wildlife out of the minimum of space. Like farms, every acre has to count, which is why there are few places where wildlife is simply left to look after itself. A special site (a steep ravine) had to be found to study the natural development of woodland in Britain. So ingrained is the concept of management that in Britain we do not seem very interested in how the natural world actually works.

This would seem odd in a big, wild country such as Canada or Brazil, but, as we ecologists never tire of pointing out, every inch of Britain is used. Most of the land has a history. Most of it is privately owned, and managed to provide income. British wildlife has long been used to living with the British, and exploiting such opportunities as we offer it. Presumably any species unable to make that crucial accommodation, such as the wolf perhaps, or Cerambyx cerdo, a huge beetle of giant trees in virgin forests, died out. But it is quite wrong to assert that because he has planted a few trees and hedges, and farms most of it, that the landscape is therefore man-made. This is a sinister reasoning, because if man has created a landscape there is an implication that he is entitled to do with it as he likes, and, if necessary, destroy it. In fact, many of our wilder places are almost unfathomably ancient, and were never planned or created. Most of our woods and commons, and even some hedges, evolved naturally in ways that are still mysterious. Whoever coined the term ‘natural history’ must have realised this instinctively. In Britain, nature does indeed have a history that runs parallel with that of humankind, often in harmony with it (man and nature in harmony is the subject of much of British art). Our relationship with the natural world has a history of its own (see, for example, Keith Thomas’ masterpiece, Man and the Natural World). Nature conservation is only the most recent phase in a long-running love affair.

Britain’s oldest farmed habitats can in fact be more ancient than natural landforms. For example, the fields of West Penwith, in Cornwall, with their strange polygonal patterns, are much older than the shingles at Dungeness or the wet levels at Pevensey, which were still under the sea when William the Conqueror invaded in 1066. A few woods have been managed in much the same way for as long as historic records permit us to see (and to carry on managing them in exactly the same way is absolutely the right thing to do: indeed, it is almost a duty to history). Past land uses were not necessarily ideal for wildlife, but they tended to leave plenty of opportunities. Butterflies could lay their eggs in sunny glades created by woodmen, before the canopy closed over again. Meadows were often full of wild flowers because farmers lacked the means to drain them dry or improve the soil (flower fields also made better hay). The highly regulated management of medieval commons could almost have been invented by a latter-day nature reserve manager. Modern conservationists are to some extent stepping into the vacated shoes of farm labourers, shepherds, woodmen and peasants, who would not have been able to read a conservation manual but knew more about conservation in practice than most of us. The challenge today is to obtain similar results by different means. Recent advances include the creative use of bulldozers, JCB diggers and suction dredgers.