Читать книгу Rewilding - David Woodfall - Страница 7
ОглавлениеColonising silver birch in glaciated valley, Alladale.
Following the end of the last Ice Age 10,000 years ago, Britain and Ireland began to colonise with birch and oak which, apart from mountain tops, became established in all of our islands. Rewilding, essentially a new concept, is the return to allowing nature to take its own course and carpet our islands once more in natural vegetation and its associated fauna. During the Mesolithic period (15,000–5,000 bce) this native forest was considerably modified by burning and felling. By the Middle Ages (500 ce onwards) the wildwood had been replaced by a mosaic of cultural landscapes, created by an ever-increasing population. The Enclosure Acts of the eighteenth century were swiftly followed by the Industrial Revolution, with its increasing demands on mineral and timber resources, and further modified our landscapes. Landscapes became empty of all of our major predators, such as wolves, and landscape modifiers such as the beaver. While our cultural landscapes contained wonderful chalk grassland grazed by huge flocks of sheep, numerous heathlands grazed by cattle and diminishing peat bogs harvested by crofters in the north and west, these landscapes were unrecognisable from their native state, much of their diversity and richness gradually stripped away. During the Industrial Revolution there was a rapid reduction in the number of people employed on the land and a consequent decline of rural communities. There were changes, too, affecting limestone pavements, peatbogs – a reduction of sheep farming led to the depletion of chalk grassland. The last time our islands possessed any degree of biological richness was the 1930s, a richness that disappeared swiftly during the 1940s when World War II interrupted food imports, leading to a massive increase in lands given over to arable crops.
By the 1960s only a handful of intensively managed nature reserves contained a fraction of our previous flora and fauna, often isolated islands in an extensive agricultural prairie, where food production was continually supported by pesticides and chemical fertilisers, further diminishing our wildlife – the future of peregrine falcons were threatened by the build-up of toxins in the food chain. In the US, scientists such as Rachel Carson began to draw the public’s attention to such concerns and the environmental movement was born. This has subsequently led to the evolution of the rewilding movement, which I would define as allowing the natural succession from open ground to forest to take place, much in the way it happened 10,000 years ago. Essentially, to allow the landscape to develop in an organic way, opening up the full range of available niches for local species. However, much of the landscape of the UK and Ireland has been so severely modified that in many cases it is a challenge to allow rewilding to take place, as this process can lead to a short-term reduction in the existing diversity. In effect, the decision on the part of conservation organisations to cease management is a form of management in itself. Many of the priorities in conservation previously seen as set in stone will have to be carefully reconsidered. Further complications emerge from the significant changes being wrought on our landscapes, ecology and ourselves by climate change.
Dinosaur footprint, Severn Estuary.
By the modern age, most of the significant apex, ‘game changers’ within our flora and fauna, were now absent – in parallel with a naturally developing climax vegetation, it was deemed necessary to reintroduce many of the key animals which significantly affect the ecology of our landscapes. These include beavers, lynx, sea eagles, and red kites: species that will help stimulate and revive ecological processes that have been absent from our lands for thousands of years. The introduction of beavers could have a significant effect on reducing the flooding of agriculture areas and towns, something that appears to have increased in both intensity and frequency. Species such as sea eagle and red kite have already demonstrated that their increased presence can have a significant beneficial effect on tourism at both a local and national level.
This work has been carried out by inspired individuals, scientists and a growing number of NGO organisations, who are working with the government conservation agencies to help negotiate with landowners, carry out research and conduct trials with reintroduced species to ensure that such populations are sustainable and equitable among our highly managed islands. In addition, rewilding calls for a greatly reduced grazing regime in our uplands by both deer and sheep, and a general reduction in the grazing of our grassland ecosystems where appropriate to increase both plant and invertebrate populations, which in turn will greatly increase our mammal and bird populations. Due notice will have to be given to our ‘cultural habitats’, e.g. downland, which have evolved through our grazing regimes. Also both the significance and value of our post-industrial sites will have to be given greater recognition as we are blessed with large numbers of places that are great examples of the beneficial effect of rewilding, without us doing anything active at all. The reduction in fishing through a system of quotas, during the last ten years, has once again made the North Sea a place in which to fish sustainably, and the introduction of many wind turbines has had the effect of creating ‘artificial reefs’ which have further increased marine diversity. This is nowhere better demonstrated than the huge growth in cetacean and grey seal populations throughout Britain and Ireland. In turn this has attracted significant populations of killer whale. The changing sea temperatures around our coasts, due to changes in the jet stream, are also enhancing our whale and dolphin populations. Tuna weighing up to 230 kg (500 lb) have been caught off the Hebridean island of St Kilda, demonstrating that our seas, too, can be rewilded.
Our agricultural landscapes, even more so than the native habitats, have the potential for great change through rewilding. Our agriculture has been heavily subsidised through the European Economic Union (via Common Agricultural Payments), since the 1970s, and this has had a profound effect on both the landscapes themselves and their biodiversity. We are about to leave Europe and at the very least this is going to produce uncertainty for our agricultural landscapes. The most likely outcome of this will be that large areas of land will not be cultivated as intensively as previously. On the other hand, financial conglomerates, pension funds and extremely rich individuals may well buy up aggregations of small farms and produce ‘super farms’, leading to even greater insensitive management of our landscapes. The first of these outcomes ought to give the opportunity for a theory like rewilding to really flourish, allowing for many natural processes to take hold once more, rather than the more manicured effects of conservation that have been attempted so far. We have reached a point in our islands’ evolution where our growing understanding of rewilding has the realistic prospect of gaining both political and popular support. This has been achieved, in part, by the rapid growth of environmental education, and the popularity of TV and radio programmes by such people as David Attenborough – informing and enthralling the public with the ‘natural world’. This in turn has inspired countless individuals, paid and voluntary, to get involved in disparate conservation projects employing both species introduction and the development of more naturally developing climax vegetation communities. Rewilding has arrived and I feel that now is the right time to publish a book highlighting all the wonderful organisations and inspired individuals who are making the UK and Ireland such a biologically rich series of islands once again.
Mawddach Estuary, Snowdonia NP, Gwynedd.
