Skye pine martens branching out

A pine marten. Picture courtesy of Lorne Gill/Scottish Natural Heritage

A species of wild animal which used the Skye Bridge to cross from the mainland to the island has spread faster than expected, experts believe.

Pine martens first arrived on Skye shortly after the bridge opened in 1995, according to Roger Cottis of the Scottish Wildlife Trust.

He said the population had spread nine miles (15km) south and west from territory near the bridge.

The pine marten is a member of the weasel family.

Mr Cottis, who is an independent wildlife consultant, said tree felling may have forced the animal's spread.

On Skye there could be potential for changes. It will be something we will be monitoring Roger Cottis

He said: "Forestry extraction has pushed them out of territory within woodland and that has increased their expansion."

Mr Cottis said it had not yet been possible to estimate the size of the population.

Pine martens can swim but strong currents in the sea between Skye and the mainland meant they were not seen on the island until the bridge was constructed, said Mr Cottis.

He added: "They are a predatory animal. Certain birds and small animals are vulnerable and there will be an impact.

"On the mainland, the birds and animals have come to terms with the pine martins' presence - there is an equilibrium.

"But on Skye there could be potential for changes. It will be something we will be monitoring."

A survey of martens on Balmacara Estate on Kyle of Lochalsh, across the sea from Skye, found an estimated population of about 48 animals.