IN COUNTLESS folk tales, the primeval forest is a dark, forbidding place, full of wolves and worse. Some say that our fear of the dark dates back to the dangers that lurked in the gloom of this closed high forest, a vestigial memory from those distant days, some 14,000 years ago, when the ice sheets retreated and nearly impenetrable forest spread across the lowlands of Europe.
But one man is challenging this time-honoured picture of the landscape our ancestors inhabited. He’s not a leading woodland ecologist, but a rebellious Dutch civil servant named Frans Vera. After graduating in ecology, Vera was headed for an unremarkable career in conservation until an accidental discovery in a Dutch wasteland made him curious enough to ask awkward questions that led him to radical answers.
In his recent book Grazing Ecology and Forest History, Vera claims that postglacial Europe was covered not by dense forest but by something much more hospitable – a park-like landscape, in fact. The closest analogue today is “wood pasture”, typified in Britain by the New Forest in Hampshire, an ancient hunting ground of kings. Here, stately veteran oaks stand tall in grassy clearings adorned with scattered copses. Ten thousand years ago, says Vera, attractive groves and glades were the order of the day, not fearsome forests.
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If he’s right, it means conservationists needn’t feel like traitors to the original landscape as they work to maintain meadows, chalk downland and wood pasture, which boast far greater biodiversity than closed forest. And if he’s right, the credit for all that open, diverse landscape goes to the big, plant-eating mammals – the elks, aurochs, tarpans and more – that once munched their way across Europe. Vera suggests that the best way to maintain these areas of countryside and preserve biodiversity may be to reintroduce the closest modern equivalents of those beasts.
It’s not often that the work of an unknown non-academic makes a splash in the mainstream, but Vera’s book has already done just that. Keith Kirby, woodland ecologist for English Nature, calls it “one of those potentially paradigm-shift books”. Francis Rose, a leading British field botanist, says it is “a magnificent book, a landmark book, of the very greatest importance to ecology and conservation”. Keith Alexander, woodland specialist for Britain’s National Trust, regards Vera’s work as “inspirational, scholarly and supremely well-argued”. And even the more sceptical forest ecologist George Peterken, formerly of Britain’s Nature Conservancy Council, finds Vera’s arguments “fascinating”.
To appreciate just how novel Vera’s reinterpretation is, consider the standard textbook account. The story goes that as the first farmers moved into Europe, they quickly cleared the closed high forest, creating productive grasslands, hedgerows and wood pasture. Without humans and their livestock, conventional wisdom has it, this transformation would never have happened.
Yet ironically, these artificial habitats turn out to be the hot spots of biodiversity today – far richer than dense stands of tall mature woodland created by modern forestry. That has put ecologists in the embarrassing position of favouring ecologically rich, yet recent and “unnatural” habitat. Worse still, they have had to depend upon farmers and landowners to keep this uncultivated land clear and prevent the return of the all-enveloping forest. But once the land is cleared, the interests of farmers and conservationists often diverge, with most farmers keen to use fertilisers and pesticides, and conservationists preferring to manage the landscape in gentler, more traditional ways.
That’s the conventional story, and even Vera once swallowed it whole. After his degree in ecology, he joined the state forestry service in the 1970s, with a post in the policy division. As a small, densely populated country, the Netherlands has long been intensively farmed. “Really there was nothing that we called ‘nature’ that was not cultivated,” says Vera. Conservationists devised schemes to pay farmers not to do certain things that were damaging wildlife, but farmers rejected the moves. The impasse seemed insoluble, and Vera began to despair: the prospects for wildlife looked bleak indeed.
Then something unexpected happened, one of those “natural experiments” that couldn’t have been planned. Part of a 5600-hectare polder that had been partially drained for industrial development turned out to be unsuitable for the purpose and was abandoned. Everyone expected the land to become a weedy, neglected wasteland. But it didn’t.
“Nature showed a side of itself at Oostvaardersplassen that we in the Netherlands no longer knew,” says Vera. Thousands of greylag geese, wild relatives of today’s domestic geese, gathered in the safety of the marshland to moult. They gobbled so much vegetation that they kept the marshland open and free from closing over with reeds. There was no need for human land managers: the grazing geese did the job themselves. “This was a real eye-opener,” says Vera. “It taught us that in large areas at least, nature could be given more independence. We could return to nature areas lost to cultivation without any danger that monotonous, species-poor vegetation – a closed reed bed or a closed forest – would be the end result.”
Herbivores in control
That set Vera thinking: is human intervention really the only way to maintain Europe’s biodiversity? After all, no one would dream of suggesting that the tropical rainforests or the savannahs of Africa require cultivation – quite the reverse. When Vera told his ecological mentor, the late Harm van der Veen of the Critical Forest Management Foundation in the Netherlands, about the geese, van der Veen made the link. He wrote to Vera: “Your geese are doing what the large mammals are doing in African terrestrial habitats – the herbivores are controlling the landscape.”
Vera says: “He inspired me to think. Perhaps our biologically rich habitats too were created not by human intervention but by large mammals – by the herbivores we have by and large lost.” In 1989, he set out to explore his ideas for a PhD. In 1997, as he completed his thesis in Dutch, colleagues urged him to publish an English version as well. Grazing Ecology and Forest History is the result, and already it has sent shock waves through the world of forest ecology.
Throughout his investigations, Vera says, oak and hazel were an invaluable guide to the past. Counts of ancient pollen grains extracted from cores in primeval peat show clearly that both these species were common in pre-agricultural Europe after the last ice age. Yet both need sunny habitats to survive – oaks for their seedlings to get established and hazel to flower properly. How could ancient forests have contained so much oak and hazel – far more than could be accounted for by occasional sunlit gaps where mature trees had fallen?
Vera argues that the landscape was dominated by large plant-eating mammals such as horse-like tarpans and aurochs, the ancestors of modern cattle, both of which are now extinct, as well as elks. He envisages a shifting mosaic of cyclical “vegetation turnover”. An area might start off as open grassland with hungry grazers mowing down any tree seedlings and keeping the land open. Where thorny thickets take hold – blackthorn, hawthorn or juniper, say – they would provide suitable nurseries where young oaks could survive and grow up into towering, long-lived specimen trees. And as these veteran trees died for whatever reason, the grazers would move in again and turn the newly relinquished land back into open grassland. In short, says Vera, grazing pressure created a shifting patchwork of habitats – grassland, scrub and tall stands of trees all intermixed in a dynamic landscape.
Many ecologists are impressed by Vera’s idea. “It does explain a lot of anomalies – for instance, why there is such a huge amount of hazel pollen in postglacial Europe,” says David Streeter, an ecologist at the University of Sussex. Previous researchers have struggled to come up with convincing explanations for the large amounts of oak and hazel pollen in primeval peat deposits. Vera’s is widely acknowledged to be the most plausible so far.
Yet his ideas may not apply wholesale across Europe. In a recent review of the pollen data in the journal Biological Conservation, Jens-Christian Svenning of the Smithsonian Tropical Research Institute in Panama concludes that Vera has oversimplified the picture. Svenning reckons that closed forest would have become predominant in the uplands of postglacial Europe, but with localised openings. But he concedes that open vegetation would have been common on flood plains, infertile soils, chalklands and in continental and sub-Mediterranean areas.
Svenning also doubts that those open habitats were created by the grazing habits of mammals alone. Fire was another key factor, he argues. Pollen expert Richard Bradshaw of the Geological Survey of Denmark and Greenland also reckons that in his enthusiasm to make a case for the big mammals, Vera has overlooked the importance of fire.
“He tends to underplay differences within the landscape,” says George Peterken, whose 1996 book Natural Woodland argues that the primeval forest was largely closed-canopy. “Variation between flood-plain forests and forests on dry slopes, for instance, could be substantial,” he argues.
“The great unknown is quantities of pasture and densities of animals,” says woodland historian Oliver Rackham, who has long argued that Europe’s native vegetation must have contained some areas of open grassland or savannah to sustain the big herbivores. Understandably, Vera is unable to estimate just how big the primeval groves and glades might have been.
Unmanaged by humans
But there could be a compromise. “The difference between the high forest and wood-pasture hypothesis may be matters of degree,” says Peterken. “Perhaps we can agree that openings lasted longer and formed a higher proportion of the natural forest than most of us have envisaged, without having to accept that wood pasture was everywhere, all the time.” Svenning also backs this view.
What most impresses even sceptical conservationists, however, is the ongoing experiment in “wilderness grazing” at Oostvaardersplassen. More than 1700 large herbivores now roam freely across the polder, which is totally unmanaged by humans.
“These animal species each have different grazing patterns and, depending on the time of year, they feed on grasses, stinging nettles, thistles, roots, tree bark, twigs and leaves, as well as reeds,” says Hans Kampf of the Dutch department of Nature Management and Fisheries. “The final appearance of the reserve will depend on the population dynamics and the eventual number of herbivores, but will probably be a half-open steppe-like grassland with scrub.” Birds abound too: greylag geese, spoonbills, cormorants, great white egrets and little egrets all enjoy the wetland.
“Of course, it’s still early days for the Dutch reserve,” says English Nature’s Keith Kirby. He would like to know what Oostvaardersplassen will look like in 200 or 300 years’ time. But even now the experiment is fuelling interest in the idea of releasing large wild mammals, or at least semi-wild ones, back into the landscape.
When Tony Whitbread and Bill Jenman of the Sussex Wildlife Trust visited the reserve in the mid-1990s, they were impressed with what they saw. Back home, they wrote to the journal British Wildlife to advocate turning large tracts of mixed English countryside over to free-range grazing by semi-wild stock. There is an ancient precedent for their ideas. “The New Forest was formed that way 1000 years ago,” says Peterken, “and the outcome of any new initiative might be a new New Forest.”
Vera goes even further. What really drives him is his ambition to free nature conservation from the clutches of what he sees as uncooperative farmers. “My work shows that we do not need agriculture to preserve our biodiversity,” he says. “What we need to do is reintroduce the animals we have lost – the wild horses, cattle, elk, European bison, red deer and wild boar – to our countryside.” At the moment, he says, “nature is the hostage of agriculture, is kept totally subordinate to it”. He claims that approach is “bankrupt” once we look at the history of our landscape from the right ecological perspective.
Stirring stuff, but how would Vera’s polemics go down with the great British public? Peterken chuckles at the thought, and says he’d love to be in the audience when Vera suggests introducing bison and boar in a public meeting in genteel Surrey, say.
All the same, perhaps it’s time for us to make amends with the landscape. We humans drove these magnificent beasts to extinction to make room for smaller, more biddable creatures. Today, Europe’s biodiversity dances to the tune of agriculture, but only because our ancestors disbanded the natural orchestra. Vera says it’s time the full mammalian ensemble returned to live wild, at least in some of the countryside.
Countries like Britain may seem too small and overrun with humans for wilderness grazing to be feasible. And yet as livestock farming becomes increasingly unprofitable, even radical alternatives begin to look feasible. Wild cattle, horses, elk, wild boar, beaver, red and roe deer and maybe even bison have every right to be in Britain, along with their predators – brown bears, lynx and wolves. If we’re ever brave and generous enough to put the mammals back, a walk in the woods might never be the same again.
Wildwood vs modern woods
Frans Vera’s recipe for creating a new natural habitat – add big herbivores and stand back – might be easy to follow, but does it tell us how to save our precious habitats from decline? After all, the Oostvaardersplassen experiment is in a wetland. It could be risky and misguided to believe its success will extrapolate to very different habitats.
Britain’s New Forest, for example, which is the nearest modern equivalent to Vera’s proposed wood-pasture, may actually suffer from too many grazers, not too few. “The practical issue is whether we should fence out the deer, ponies and cattle,” says forest ecologist George Peterken. He worries that the New Forest will steadily degenerate if grazing by deer and ponies continues at the present rate. Whatever the primeval wildwood was like, knowing more about it may not help us to decide how best to manage the woodland we’ve inherited.
Woodland historian Oliver Rackham agrees: “I don’t think Vera’s argument has much bearing on the most urgent problem of woodland conservation in Britain: the proliferation of deer. Ancient woods are now suddenly confronted with artificially large numbers of exotic species of deer,” he says. “These live in a wood and eat everything edible within reach, but are not constrained by the size of the wood, for they are sustained by feeding on crops outside. They impoverish the wood as a habitat, and in the long run compromise its continued existence.”
Vera doesn’t contest this, but argues that modern forests are not directly analogous to the original vegetation of the lowlands of Europe. He claims that in ancient times, regeneration of trees would have occurred in patches of thorny scrub on the edges of forest, not in the forest itself – resulting in shifting woodland habitats. The trouble is, today’s forests can’t get up and walk: we humans have commandeered the land.