IT has become the stuff of legend - big cats roaming wild in the English countryside.

But now it appears pumas, lynxes and other big cats do exist in ever greater numbers and could even be breeding.

According to an exhaustive study by the British Big Cats Society, there have been 2,052 sightings in the past 15 months - equivalent to four a day - compared with a mere 438 in 2001.

The animals seem to have taken a particular liking to this part of the world, with 127 sightings reported in Yorkshire, and a further 18 logged in the North-East during the period.

Overall, the North had 288 sightings, an increase of more than 320 per cent, the largest increase anywhere in the country.

Society founder Danny Bamping called for Government support in undertaking a properly funded scientific study on the subject.

He said: "There is little doubt that big cats are roaming Britain."

Last night, Dr Melissa Bateson, royal society research fellow in the school of biology at Newcastle University, said it was entirely possible that big cats were now producing offspring.

She said: "Food could be an issue, but as long as there is enough of a supply of things like sheep, it shouldn't be a problem."

Dozens of sightings of big cats have been made in recent years. In Durham, a puma-like animal has been spotted in areas including Sedgefield, Barnard Castle and Bishop Middleham.

Clusters have also been reported around the Middleton Tyas, North Cowton and Scotton areas, in North Yorkshire.

Police Sergeant Eddie Bell logs an average of two big cat sightings a month.

Among them were three sightings by separate witnesses who reported a spotted leopard.

"When we plotted them, the cat appeared to be travelling in a straight line through Upper Teesdale and into Alston," he said. "Over a period of 36 hours it was travelling north and had been seen by three unrelated and credible witnesses."

Sgt Bell, one of Durham Constabulary's wildlife liaison officers, has also recovered lynx droppings following a number of sightings near Derwent Reservoir, in County Durham.

He added: "There is no doubt we have puma - the evidence is overwhelming, although I would say only one in ten sightings turns out to be genuine and not a mistake."