The RSPCA hospital at East Winch has nursed more than double the number of common seals than usual over the last year.

The hospital would normally expect to see around 60 come through its doors.

But during the last 12 months the centre dealt with 121 – although there has been no apparent link between the cases.

Centre manager Alison Charles said there were no signs of a single problem which was affecting high numbers of seals.

'It could be any number of things. I was quite surprised myself when I did the head count and realised how many we had.

'There is no single problem that is affecting them all, but the number is high. It's not a case of a new disease hitting them. Hopefully it means that there are just more seals around,' she said.

Common seals, also known as harbour seals, breed off the North Norfolk coast but numbers were decimated by Phocine Distemper Virus (PDV) in 2002.

Around 4,000 animals died when the disease hit colonies in the county.

The same disease had also struck earlier, in 1988, and numbers are still recovering from the losses from both outbreaks.

'Numbers of seals have been down over the years since then, but the last year has seen a rise in the amount we are seeing at the centre,' said Ms Charles.

The RSPCA centre has been operating since 1992 and in that time has cared for hundreds of seals – both common and grey.

It was at the forefront of the battle to save seals struck by PDV and those orphaned by the outbreak.

The centre is currently in the quieter period before common seals begin breeding again.

Scientists from the Sea Mammal Research Unit (SMRU), in Scotland, carried out a head-count of Wash seals in the autumn.

The results are not yet out, but Ms Charles said she was hoping that last year's busy spell was down to increasing numbers which would be reflected in the SMRU figures when they are released.

A record number of grey seals were born between November and Christmas at Blakeney. Around 700 pups were born at the site as opposed to just 25 recorded in 2001.

The rise has been attributed to less interference from people and predators coupled with the seals returning to traditional breeding grounds.

donna.semmens@archant.co.uk