SIX-week-old Otto, the otter cub, had been searching from its mother and sibling for days, and being too young to eat fish and invertebrates, sounded a plea for help as he lay exhausted on a North Yorkshire riverbank last Friday.

Luckily for Otto, a father and son walking their dog in the grounds of Duncombe Park, one of North Yorkshire’s foremost historic houses, heard a loud mewing sound and waded across the River Rye to investigate.

They found the tiny creature curled up, camouflaged and unresponsive on the riverbank, and as he made no attempt to move away from them they assumed he was injured.

The pair called Edgemoor Veterinary Practice in nearby Helmsley, who alerted Krista Langley, manager of The Wildlife Haven Rescue and Rehabilitation Centre, in Thirsk, as volunteers conducted an extensive search of the riverbank in an unsuccessful attempt to find the otter's family and holt.

Mrs Langley said: "We always try to keep otters in their habitat, but he was very poorly, underweight, dehydrated and completely exhausted, so if he had been there a couple hours more he may not have been alive.

"We scooped him up and took him back to the centre, knowing it would be a long haul to pull him through.

"He weighed under a kilo when we brought him in and had us worried in the evening after going quite limp and refusing to take fluids, but after persevering we eventually managed to get him to drink small amounts from a syringe - and he finally took a full bottle of milk at 4am."

After feeding Otto every four hours for several days, Mrs Langley said the mammal had gained weight, settled into a routine and had started playing.

She said: "At his age, he should still be in his holt, he is too young to swim and still is wobbling around on his baby legs.

"Something could have happened to his mum and he has become hungry and crawled out and along the bank."

Mrs Langley said Otto would remain at the haven, which is appealing for donations to extend its facililties after taking in 1,300 creatures last year, until he was weaned, when he would be moved to a rehabilitation centre where he would stay for a year.

For details about the haven, or to donate, visit thewildlifehaven.co.uk or call 01845-526567.