Around 5-6,000 years ago, humans began to clear forests for fields and settlements, and hunting of both herbivores, for food, and carnivores, as competitors for game and a threat to livestock, intensified. Aurochs and wild horses were hunted to extinction, and elk, bison, beavers and wild boar were lost from the British Isles, along with wolves, bears and lynx. Across Europe, these species were also persecuted until only wild boar and the three species of deer – red, roe and fallow – were common, and carnivores were restricted to remote, often mountainous areas by the middle of the twentieth century. The resulting change in the landscape is strikingly evident in Britain, with over 90% of forest cover being lost, leaving vast areas of grassland, moor and heath. Nowhere is this more noticeable than in the Scottish Highlands, with its thousands of square kilometres of denuded hillsides.
With no natural predators to keep them on the move and prevent over-browsing of one area, deer have contributed to the failure of the natural process of regeneration of woodland by nibbling tree shoots and destroying saplings. Complete exclusion of deer is not necessarily the answer. Our native forests evolved with browsing herbivores keeping the more vigorous understorey plants in check and allowing slower growing plant to compete. When these browsers are excluded, for example by deer fencing in forest regeneration schemes, the understorey that grows back is dominated by the faster growing species and diversity is much lower than in the original forest. Seed germination is also affected by the lack of wild boar to disturb the ground. Berry bearing shrubs rely on a certain amount of ‘pruning’ by browsing deer to promote denser shoot growth and abundant berry production, but over-browsing will also reduce berry crops.
Thus, forest biodiversity and productivity benefits from the presence of deer and wild boar, but relies on the presence of predators to prevent overgrazing. In Britain, hunting can be argued to have replaced the pressure of natural predators, but the pursuit of economic gain rather than ecological benefit has meant that deer numbers remain high and there is very little forest regeneration.
Examples of how predators can regulate the impact of herbivores on vegetation can be found in the USA. Shortly after wolves were reintroduced to Yellowstone National Park, biologists noted that willow growth along streams and rivers began making a recovery, after years of over-browsing by elk. Beavers began to re-colonise areas of the park where willow was recovering, in turn creating wetland habitat for a number of other specialist species of plants, insects, amphibians and birds. This effect is known as a trophic cascade, where a change affecting one species higher up the food chain indirectly affects those lower down. Another example of a trophic cascade that has occurred in Yellowstone is the availability of carcasses to other species, from ravens, magpies, eagles, coyotes and small mammals and birds, down to beetles and flies.
The presence of large carnivores then, can influence the flora and fauna of an ecosystem and help to keep it in a more natural and diverse state than areas where there are no predators.
Just how important is wildlife and a natural landscape to people? Before the eighteenth century, wilderness was regarded as something to be conquered and tamed. In the late 1700s, the Romantic poets, writers and painters ushered in a new appreciation of wild places; Jean-Jacques Rousseau wrote “Nature flies from frequented places. It is on the summit of mountains, in the depths of forests, on deserted islands that she reveals her most affecting charms.” Today, an ever-growing number of people are turning to nature as a sanctuary from the hustle and bustle and pressures of modern life, and the benefits of this are now being backed up by science. An English Nature report published in 2003, titled Nature and Psychological Wellbeing, cites research that shows people who have regular encounters with wildlife had better mental health than those who did not. In a MORI poll for the National Trust, more than 80% of respondents regarded encounters with nature as vital in helping deal with the stresses of modern life. In the USA, mental health recovery programmes often include wilderness excursions and counsellors recognise the therapeutic and stress relieving effects of time spent in nature.
The psychological benefits of wildlife can also translate into economic benefits. In the USA, some $17 billion is spent on wildlife watching each year, and eco-tourism and wildlife watching holidays are becoming more and more popular. People remain particularly fascinated by predators; it has been estimated that wolf reintroduction in Yellowstone benefits the local economy by some $23 million each year, such is the appeal of wolves in a wild landscape. This has positive implications, particularly for some of the less economically developed countries in Europe, where the majority of the continents remaining large carnivores live.
Even though they do not necessarily need true wilderness for survival, apex predators such as wolves and bears have become symbols for protection of the last wild places. The value of such symbolism has started to be more widely recognised, even by scientists, who are beginning to talk about the role of our emotional response to the wolf and what it represents, as a driving force behind much scientific research and conservation. The reasons for this emotional response are many and complex, but in a world where we increasingly control our environment and become isolated from nature in our everyday lives, environmental activist and author Edward Abbey best sums up our sometimes contradictory attitude to wild places and animals; “Why wilderness? Because we like the taste of freedom. Because we like the smell of danger.” Without large carnivores, some of that ‘smell of danger’ is lost, and there is a sense that the wilderness is no longer truly wild. That in itself is surely a good reason to conserve what is left before it is all gone.
There are persuasive arguments for the continued presence of large carnivores and their herbivore prey. If we can find a way to reconcile the physical, economic and psychological needs of human beings, and the requirements of wolves, bears and other predators it will be to the benefit of both, and also a multitude of other species with which we share the planet.
Peter Taylor “Beyond Conservation”, Earthscan 2005
Douglas W Smith “Decade of the Wolf”, The Lyons Press 2005
Stephen Moss “Wild Therapy”, BBC Wildlife, February 2005
Edward Abbey “Beyond the Wall”, Holt & Co 1984
Geral T Blanchard “Grizzly Lessons”, iUniverse 2004
Matt Cartmill “A View to a Death in The Morning - Hunting and Nature Through History”, Harvard 1996