Nature Conservation. Peter Marren

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СКАЧАТЬ 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.

      Some millennial stocktaking

      About 30 years ago, when I was just setting out into the nature conservation world, we used to be slightly apologetic about British wildlife. Almost anything we had, other European countries had better, we thought. Britain has few endemic species worth mentioning, apart from Primula scotica (the Scottish primrose) and the good old red grouse (which, ornithologists insisted, was the same species as the bigger, better-looking continental willow grouse), nor much of world importance, apart from the grey seal (which we were then culling by the hundred) and maybe the gannet. Since then, Britain’s stock has risen considerably. We have places such as the New Forest, St Kilda and the Cairngorms, which are important after all, and more old trees than anywhere north of the Alps. Our marine life, estuaries and Atlantic oak woods are pretty special, and Britain is right at the top of the European liverwort league. I was slightly staggered to hear we have 40 per cent of Europe’s wrens. If Britain sank beneath the waves, quite a lot of species would be sorry.

      Britain’s wildlife is important in another way. Natural history is very popular – we have 4,000 RSPB members for every species of breeding bird – and we are very good at it. (Who wrote The Origin of Species? Who lived at Selborne?) Britain probably has the best documented wildlife in the world – all right, we might tie with the Dutch and the Japanese. Our 60-odd butterflies are nothing on the world stage, but the expertise acquired in studying them has been exported worldwide. British bittern experts are in demand internationally, though we have only a handful of bitterns. We might not be much good at protecting wildlife, but we certainly know a lot about it. How well, in fact, are our wild animals and plants faring at the start of the new millennium?

      There are some grounds for optimism. The loss of wild habitats with which we are sadly so familiar can now be seen in a historical context – as a feature of the domination of intensive agriculture (including forestry) between 1940 and 1990. The statistics of habitat loss put together by the NCC in 1980 have been much repeated, and certainly paint a grim picture. I will not march through them all again, since statistics tend to have a numbing effect on our jaded twenty-first century minds, and they are meaningless without context. For example, what does the loss of 95 per cent of ‘neutral grassland’ mean? It does not tell us whether all the lost ground was of importance for wildlife, nor whether what remains is of the same value as it was. It does, however, imply that something pretty far-reaching has happened to the landscape, and that perhaps only one unimproved meadow in 20 has survived. Meadows are the biggest losers of the habitat loss stakes, but we have lost almost as much wet peatland and ‘acid grassland’, mainly on former commons and village greens, and about half the chalk downs and natural woods that existed before 1939.

      The red grouse, Britain’s most celebrated endemic animal, adapted for life on heather moors. (Derek Ratcliffe)

      The official nature conservation agencies publish annual estimates of habitat loss and damage in their annual reports. The loss is ongoing, and although it has fallen since the peak in the agricultural high noon of the 1970s, there is now less habitat to damage. The problem with the figures is that, however they are defined, damage assessment is relative. Some types of ecological damage, such as eutrophication, need a trained eye, while others, such as surface disturbance, may look like damage, but may be harmless or even beneficial. Moreover, the agencies have a bad habit of changing their method of calculation from year to year, and since devolution it has become maddeningly difficult to compare what is happening in England with Scotland or Wales or vice versa. All the same, the losses indicate that statutory protection of wild habitats has not been as effective as many had hoped.

      The decline of lowland heath in six parts of England over two centuries. (From Nature Conservation in Great Britain, NCC 1984)

      The concensus at the turn of the millennium is that loss and damage has slowed considerably and for some habitats may have halted. SSSIs have acquired a greater land value because of the grants they now attract, and SSSI protection is also more effective than formerly. Also more of them are owned or managed by conservation bodies or benign private owners. For at least one well-documented habitat, hedges, removal is now offset in terms of length by newly planted or repaired hedges (quality is not assessed). Hedgerow removal peaked between 1955 and 1965, when many of the open barley prairies of eastern England were created. The process went on in lower gear, with about 2,000 miles (3,200 kilometres) of hedges removed per year, mainly by arable farmers, but also for urban development, roadworks and reservoirs. The Government’s Countryside Survey found virtually no overall decline in hedges between 1990 and 1998, except in neglected ‘remnant hedges’: about 10,000 kilometres (2 per cent) of hedges were removed, and a similar amount planted. But the survey found evidence for some loss of plant diversity, especially tall grasses and ‘herbs’. The reason why hedges have stabilised is because government no longer pays the farmer to pull them up, but pays him to plant them. Stewardship and other agri-environmental schemes are the main reason why hedges are still planted.

      We have lost a lot of wildlife habitat, but conservation bodies saved many of the best places, and the story is by no means all doom and gloom. Today’s problem, which I will turn to in the last chapter especially, is the reduction in habitat quality and diversity, which is all the more insidious because it is hard to measure precisely. When we turn to species, the overall picture is the same. Many species – possibly most species – have declined over the past half-century, but relatively few have become nationally extinct. Some once believed extinct have since reappeared, or have been reintroduced in biodiversity schemes. The best-known victim of the past half-century, the large blue butterfly, has been reintroduced from Swedish stock, which closely resembles the lost British race. Thanks to thorough research and ground preparation by Jeremy Thomas and David Simcox, the project has been a resounding success, and several introduction sites are now open to the public. But there is a very large disparity between the small number of recorded extinctions and the much larger number that seem to be approaching extinction. For example, the JNCC considers that about 20 native wild flowers are extinct (though my own tally makes it nearer ten), but some 200 face extinction in the short or medium term. Similarly, some 29 lichens are considered extinct, but 148 are ‘endangered’ or ‘vulnerable’. The implication is that conservationists are good at saving species at the last ditch, but bad at preventing them from getting that far.

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