A new study to assist the revival of one of the UK's rarest mammals is underway in Northumberland.
Pine martens, which were once written off as extinct in England, are becoming more common in Kielder Forest, after being detected on cameras set up to monitor red squirrels four years ago. The agile tree climbers look similar to a ferret or stoat but are significantly larger, with adults growing to more than two foot long and having a bushy tail.
Martens were first spotted in Kielder nearly four years ago, and it's believed to have been the first time they have been in the forest park since tree planting in 1926. And now Forestry England, working with conservationists Johnny Birks and John Martin, have erected 50 pine marten boxes for the first time in England's largest woodland.
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The breeding sites will be installed in one of two widely separated areas where pine marten scats have been detected. In the other area no boxes will be used, allowing experts to assess their impact.
It is thought to be the first time such a study has been carried out nationally. The creature is likely to be already breeding in Kielder, and it is hoped that this project will confirm this, alongside giving pine martens a boost.
Wayne Penrose, Forestry England Ecologist, explained: "Martens could have made their way here from the population in southern Scotland. But one thing the forest currently lacks is natural denning sites in trees, so boxes should make up for this.
"Ground surveys will be carried out once a year, with scats being collected and DNA tested to determine the population. Where martens take up residence we may install cameras. It's wonderful having this magnificent animal back in the forest."
Once widespread in the UK, persecution and habitat loss saw the marten population crash during the 19th and early 20th centuries. Today, it's major stronghold is the Scottish Highlands.
However, the mammals are moving south, and alongside Northumberland there are now populations being monitored on the North York Moors and the New Forest. Forestry England is also taking part in England's first reintroduction of pine martens in the Forest of Dean in Gloucestershire.
Johnny Birks, one of the UK’s leading authorities on the species, added: "For some years we have had sightings in England, but little in the way of hard evidence until recent times. So it’s great that we are now talking about a recolonisation, which is in addition to a reintroduction of martens in the Forest of Dean three years ago. A big advantage of Kielder is its sheer size, so martens can expand their territory to find food . The boxes are pretty simple and have been erected up to four metres high on trees."
Kevin May, Forest Management Director at Forestry England, said: "Pine martens have historically been part of the ecology of Northumberland and Cumbria, so they are rediscovering their niche. Their return also underlines that as well as being England's most productive woodland for timber, Kielder Forest represents a unique mosaic of habitats."
Pine martens are just one of many species in Kielder Forest, with ospreys recently returning from their annual winter migration to Senegal and England's largest red squirrel population present in the woodland. It's even thought that the resurgence of pine martens could improve the fortunes of red squirrels in the area.
Currently, rangers and contractors work to check the advance of grey squirrels in the forest, but where reds, greys and pine martens co-exist, studies suggest that pine martens can reduce the number of greys.
