This orphaned otter cub is on the mend after it was rescued by dogwalkers who found it lying unresponsive on the banks of a river.

The six-week-old cub, named Otto, was discovered by the father and son when they heard its cries while walking in Duncombe Park, North Yorkshire, last week.

It was taken to the Wildlife Haven Rescue and Rehabilitation Centre, where staff will care for it until he is fully recovered and ready to be released back into the wild.

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Rescued: The six-week-old cub, named Otto, was discovered by the father and son when they heard its cries while walking their dog in Duncombe Park, North Yorkshire, last week. Above, Otto cuddling with a toy

On the mend: Otto, pictured in the rescue centre, was severely underweight, dehydrated and completely exhausted when he was rescued but he has been bottle fed every four hours and is now gaining weight

Volunteers were unable to trace the family of the young otter and do not know what happened to its mother.

Krista Langley, who runs The Wildlife Haven from her home in Thirsk, North Yorkshire, said: 'When he came to us he was really very poorly but he is doing brilliantly and recovering well.

'We don't know whether something has happened to mum or if he has gone on a bit of an adventure on his own, but when he came in he had been off his mother's milk for some time.

'Otto will stay here until he is weaned and then we will move him to a rehabilitation centre where he would stay for about a year until he is ready to be released.

'But at the moment he is too young to be on his own.'

Otto was severely underweight, dehydrated and completely exhausted when he was rescued but he has been bottle fed every four hours and is now gaining weight.

Loved: Krista Langley, who runs The Wildlife Haven from her home in Thirsk, North Yorkshire, wakes up in the night to feed Otto with a special milk formula designed for puppies. He will soon move on to fish

Ms Langley said: 'We always try to keep otters in their habitat, but if he had been there a couple of hours longer he may not have been alive.

'We took him back to the centre and he weighed less than one kilo.

'He had us worried in the evening after going quite limp and refusing to take fluids but we persevered and eventually managed to get him to drink small amounts from a syringe at first.'

It is like having a baby again. Young otters who have been separated from their mothers need a lot of reassurance and love. He is a very affectionate and playful little thing, and likes cuddles Krista Langley

Ms Langley wakes up in the night to feed Otto with a special milk formula designed for puppies. He will soon move on to fish.

She said: 'It is like having a baby again. Young otters who have been separated from their mothers need a lot of reassurance and love.

'He is a very affectionate and playful little thing, and likes cuddles.'

The cub will stay with Ms Langley for around a month before being moved to another larger centre where he will be able to have contact with other young otters.

But Ms Langley, who set up the centre with her daughter, Lauren, said: 'The plan is always for him to be released back into the wild, which will probably be after around a year.

'I will miss him when he goes. It was difficult when he first came, you never know if they will survive or not. But he got through the first night and has been going from strength to strength ever since.

'We don't know what happened to the rest of his family. We searched the river to see if we could find any siblings, but there was no sign.

'He is too young to be out of the holt, he would have died if he hadn't been found. We think something probably happened to mum, and he crawled out.'

Recovery: The cub, pictured, will stay with Ms Langley for around a month before being moved to another larger centre where he will be able to have contact with other young otters