KOI-KILLING otters have returned to Swindon to feast on fish in people’s ponds.

Dozens of people have spotted the creatures in their gardens around town over the past year.

Nigel Sawyer of Old Walcot saw the decapitated and chewed-up carcasses of his prized 12-year-old koi left lying around the lawn.

He said: “I have had these five fish for years and there have been foxes, badgers and herons frequently visiting the garden but they never touched the koi.

“I was up at 6.30am for work and that’s when I discovered the remains spread over the back garden, with otter poo nearby, and the pond had been emptied.

“I’m gutted, it was not a nice sight to wake up to. They were quite old for koi, and large, they would have been worth around £1,000.

“I don’t blame the otters for doing what they did. Maybe they were released somewhere without a regular food supply so they’re searching for food in other parts of town.

“The only water near us is the Lawn lakes, which is almost on my doorstep, so the otters must be around there somewhere. Our neighbour told us he later saw five of them in our garden the next day.”

The Adver first reported on the slippery mammals in March 2018 when Pete Bayley from Old Town blamed them for killing three koi and around 40 goldfish, leaving just one left in his pond.

Mr Bayley then bought a motion-sensitive night-vision wildlife camera and caught the culprit during a return visit. Mr Sawyer plans to do the same.

Mr Sawyer added: “A wildife camera’s on the way but I’m not putting any more fish in the pond just in case. That’s it for me now.

“I want to warn other people with koi to protect them. I didn’t want to put netting over the pond but that might have been worth doing.”

Initially, netting did not prevent otters from reaching Mr Bayley’s koi last year but stronger, tighter netting has successfully seen off repeated attempts by the fish-lovers to get to his new batch of goldfish.

Mr Bayley said: “They haven’t been in my garden since March because they just bounce off the new netting and can’t get through any more, so the fish are happy and safe.

“A friend at the allotments and people I spoke to at the garden centre mentioned that their fish had been eaten too, so they’re obviously spreading.

“A lot of people detest them and I was annoyed at first about it all but I’m glad I got decent footage of the otters with the camera.

“You can either work with nature or ignore it, but people should do something to keep their fish secure. The net must be as tight as possible otherwise they’ll find a way under it.”

Otters are currently protected under UK law as their population has declined rapidly in recent years.

Founder of the UK Wild Otter Trust Dave Webb said the trust had received a “remarkably high” number of sightings from the Swindon area this year.

He said: “We’ve had around 40 reports so far. It’s quite common for them to visit garden ponds.

“Although they’re mainly in rivers, they don’t need to be near water and can travel up to 40km from a water source to find food, sometimes in a single night.

“Traditionally, these sightings happen when river levels rise and there’s heavy rainfall, or if it’s spring because that’s a favourable time for them to breed, then in the summer they have cubs to look after and hunt in shallower waters.

“Put heavy steel mesh over the pond with a gap between the mesh of at most 75 millimetres – they can fit through anything more than that and are not easy to stop.”