With his tiny flippers, wide dark eyes and fluffy white coat it's hard to believe the adorable Arthur will soon be a fish eating machine, devouring up to nine kilos of herring a day.

The grey seal pup is the first to be cared for at the RSPCA East Winch Wildlife Centre, near King's Lynn, this season and many more are expected through the doors in the coming weeks.

Autumn sees scores of females give birth along the Norfolk coast, leaving their silky pups ashore to build up blubber while they search for food.

It is when the mums fail to return that the RSPCA is called on to rear the pups and its staff spend weeks building their strength with bucketful after bucketful of fresh fish.

Arthur was rescued from near Newbiggin-by-the-Sea in Northumberland last week after he was found alone with his umbilicial cord still attached.

At three weeks old, he is just starting to lose his white baby fluff and develop his adult coat.

Staff at the centre are currently coaxing Arthur to eat, but the youngster will be getting through 30 herring a day by the time he's ready to be released back into the wild.

'It costs �23.10 to feed a grey or common seal for a week and that doesn't include medication or staff time,' said centre manager Alison Charles.

'We feed them more than they would eat in the wild because we have to get them ready for release as soon as we can.

'Arthur weights just under 12kg at the moment so he really needs to fatten up. It varies, but they usually go back to the wild at about four months old and we like the males to reach 45kg before we let them go.'

It is normal for grey seal pups to be left on the beach on their own for long periods of time. They grow fat on their mother's rich milk and, when the time is right, they head out to sea and instinctively know how to fish.

'Passersby may mistakenly think that the pup has been abandoned but in most situations this is probably not the case,' Mrs Charles said.

"We ask that if people do see a young pup on its own – observe it from a distance and if after a long period of time the pup's circumstances haven't changed then that is the time to seek expert help.

'Young moulted pups will often haul out (lie) on the beach to relax. This is perfectly normal behaviour and does not mean they are sick.

'As much as seals are adorable to look at, they do bite, and grey seal mothers are very protective and will defend their young, just like any mum would do, if they felt their offspring was under threat.'

In genuine cases of abandonment, it is never really known what happens to the mother. It is thought Arthur's mum may have fallen ill or even forgot where she left him.

'We never want seals to come in, but we hope Arthur can have some company soon,' Mrs Charles added. 'He's all on his own at the moment.'

The centre expects to take in about 65 seals this season and is still caring for 28 common seals, many of which have lungworm.

To mark the Jubilee year, all the pups will be named after kings and queens.

Anyone interested in helping the centre with its work can sponsor a seal for a �20 donation of �20. Donors can name a seal and will receive a photograph, certificate and six monthly newsletter.

To find out more or to make a donation, call 0300 123 0709 or email eastwinch@rspca.org.uk.

If you do spot a seal in distress please contact the RSPCA cruelty line on 0300 1234 999 for advice