One of the UK's rarest mammals, the polecat, is beginning to re-establish itself in parts of northern England.

The species used to be widespread throughout Britain, but its numbers dropped sharply at the end of the 19th Century because of hunting and trapping. It completely disappeared from Scotland and most of England. But it retained a toehold in west Wales, around Aberystwyth.

And now conservationists say the polecat is beginning to cross from Wales into England to re-establish itself in a few secluded spots. Over the last 10 years or so, isolated animals have been occasionally seen in Cheshire.

Now the Cheshire Wildlife Trust says it has evidence of several polecats in the county. They are living in woodland at Little Budworth, near Tarporley, and in the Delamere Forest, not far from Northwich.

More details needed

The trust's polecat specialist, Becky Palmer, said: "We have been monitoring the slow return of the polecat in the area, and are keen to safeguard its recovery."

"It's vital that anyone who spots a polecat gets in contact with the trust, so that a detailed survey can be carried out and its natural environment and existence can be protected.

"The best time to see a polecat is at dusk, and at this time of year the best place to look for one is among secluded hedgerows and woods."

The polecat is a protected species. It resembles a large stoat, and can reach about half a metre in length.