Pine martens make comeback in UK after leading a secret life for decades

The pine marten, one of Britain's rarest and most elusive mammals, is back - and the reason is it never quite went away. A new report reveals pine martens are not confined to the fringes of the UK as was assumed, but that they have been living a secret life under our noses for decades.

Photograph: Natural England/PA

Pine martens are related to weasels and otters and are agile, inquisitive, and about the size of a small cat. With their deep chestnut fur and yellow bib they are one of Britain's prettiest mammals. They are also supreme forest predators and hunt voles, rabbits, squirrels, birds with a taste for honey, nuts, fruit and fungi.

The beautiful fur made their pelts valuable, and their killer instinct, particularly when it came to pheasants and partridges, made them enemies of gamekeepers. Pine martens were consequently persecuted to extinction in most parts of Britain but, even with full legal protection in 1988, only small enclaves hung on in remote parts of northern Scotland, Cumbria and north Wales. Or so it was thought.

The report from the Vincent Wildlife Trust, based on 12 years of research and sightings, reveals a surprise: pine martens are largely still present in the same parts of England and Wales from which they were recorded in the past. This includes areas such as Carmarthenshire, Montgomery, North York Moors and the Cheviots but also sightings in Cambridge, East Sussex and Northampton.

How did this 80cm-long nocturnal tree dweller pass unnoticed for so long? The report's author, pine marten expert Johnny Birks, told the Guardian: "Not everybody overlooked the pine martens. Some dedicated naturalists, who had been watching them for many years, kept hope burning that the species' presence would be recognised. The trouble is the authorities are used to cheap and easy survey methods which don't work on something as elusive and scarce as pine martens and the wrong perception has arisen that there were none left."

For the period 1996 to 2007, researchers analysed records, talked to people with convincing sightings, collected roadkill and used DNA testing on scat – pine marten poo – to slowly piece together the true picture.

The story also tells us how important the observations of amateur naturalists are, said Birks. "There are cultural changes towards instant results and fewer people dedicated to plugging away, building up their skills hoping to strike it lucky in pursuit of rare animals. These sorts of naturalists are as rare as the animals themselves."

The presence of pine martens in England and Wales is not thought to depend on escapes from zoos or reintroductions but it seems the tenacious little martens have been hanging on despite us. "They tell us about a species' resilience to tick over until conditions improve," said Birks. "With fewer killed and more woodland planned, there is hope and optimism the pine martens can keep going."

The "reappearance" of the pine marten is a further encouragement to create new woods and protect old ones, particularly old trees with breeding holes in them, said Birks, as well as championing greater connectivity between woodlands so pine martens can stay aloft and away from predatory foxes.

The new coalition government has pledged to launch a national tree planting campaign, with a target of a million trees. It is expected to begin in the autumn.

(submitted by Chad Arment)