The beaver is a gentle, retiring creature. He’s a rodent lumberjack and he’s OK: he works all night and he sleeps all day. And he makes a lovely waterproof hat.

But this shy herbivore has now become the focus of a ferocious battle, at the very moment the wild beaver is returning to these islands for the first time since the Middle Ages.

Later this year, four families of European beavers (Castor fiber), trapped in Norway during the winter, will be released beside three small lochs in a remote wooden glen in Knapdale, Scotland, in an experimental pilot scheme that is seen as the prelude to a wider release.

This will be the first mammal species ever to be formally reintroduced in Britain. To supporters of the project, the beaver colony in Knapdale represents an environmental breakthrough, an opportunity to restore to its proper place in the British ecosystem an animal driven into extinction by man. To opponents, including many local landowners and a number of celebrities, the beaver is a menace, a large, disease-spreading aquatic rat that will hack down trees, clog up waterways, flood fields and damage fishing.

At one level, the beaver battle is a fight between environmentalists on one side and farmers and fisherman on the other; it is also a dispute, in some ways, between town and country, with political and class overtones. But more fundamentally, it is a philosophical conflict, raising vital questions about what (and who) the countryside is for, how humanity should interact with wildness on an ever more crowded island, and whether, in ecological terms, the clock can be turned back.

In popular culture, we have made the eager beaver into a symbol of industriousness. In C.S. Lewis’s imagination, the beavers of Narnia were generous, hospitable animals and terrific cooks. Such is our admiration for the beaver, the species has been made into a verb, and a sexual euphemism; but mostly, we made them into clothing, perfume and supper.

Beavers tend to mate for life, giving birth to one or two young a year. The beaver’s lodge may look like a random mound of sticks and mud, but it is carefully designed, with underwater entrances to prevent any other animals from getting in. Typically, the lodge will contain two dens, an outer chamber to dry off in, and another den in which the family lives.

Beaver fur is uniquely thick and soft, with over 10,000 hairs per square centimetre. Easy to trap, beavers were hunted ruthlessly, for their pelts and for the secretion in their anal glands, known as castoreum, which is used to make scents such as Lancôme Caractère and Shalimar, and to flavour cigarettes. You may never have seen a beaver, but you have probably smelt the distinctive pong of beaver bum.

Castoreum also contains salicylic acid, the principal ingredient of aspirin, and was used in ancient times to treat headaches, fever and hysteria, and as an aphrodisiac. The second largest rodent in the world, beavers also made good eating. The Roman Catholic Church ruled that the beaver was really a fish, so it could be eaten on Fridays. The Finns favour beaver in a cream and bilberry sauce.

The beaver, in short, was too useful for its own good, and by the 16th century it had been exterminated in Britain and most of Europe. Only a few colonies survived, in Germany, France, Norway, Belarus and Mongolia.

It was not until the Twenties that European governments began making serious efforts to restore beaver populations. Since then, beavers have been reintroduced in some 24 countries, with varying results. The possibility of releasing beavers in Scotland was first mooted in 1994, but it was not until last year, following intensive studies and a series of consultations with local residents, that a licence was finally granted to import beaver for a controlled trial period to see if they would thrive in the Scottish wilds.

In November, four families of beavers numbering some 20 animals in all, were trapped in Telemark in Norway. The animals are currently held in quarantine in Devon. In May, they will be taken to the remote trial site near Lochgilphead in Argyll, owned by the Forestry Commission Scotland, and released into pre-built lodges, ready stocked with turnips and carrots to ease the transition to their new homes.

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