THEY were once on the brink of extinction but otters have made a dramatic comeback in Lancashire.

The playful semi-aquatic mammals have reappeared in places where they have not been seen since the industrial revolution including the River Ribble.

A recent survey on the local waterway delighted conservationists as they saw a 44 per cent increase in otter populations in the past three years.

The River Ribble and the Irwell in Greater Manchester are two of ten rivers chosen for pilot projects run by the Environment Agency to encourage the animals to return.

The schemes aimed to improve the health of UK rivers by urging farmers, businesses and local communities to reduce water pollution.

And in the North West this has contributed to a 50 per cent increase in the furry mammals - descendents of the same family as weasels, polecats, badgers and wolverines.

The resurgence of the otter, which is top of the food chain in river environments, is an indicator that English rivers are at their healthiest for more than 20 years, according to the Environment Agency.

Toby Willison, North West director at the Environment Agency, said: “The recovery of otters from near-extinction shows how far we’ve come in controlling pollution and improving water quality and river habitat.

“Otters, salmon and other wildlife choosing to live in the North West’s shows us that our rivers are the healthiest they’ve been since the industrial revolution.”

Plans are now in the pipeline to transform more than 9,500 miles of rivers in England and Wales by 2015 – the equivalent of the distance between the UK and Australia.

The Environment Agency, working with partners including wildlife and angling organisations, has this year been granted an additional £18m of funding by the Department for Environment, Food and Rural Affairs to help more English rivers meet new EU targets on the health of rivers.