IN its time, the Blue Cross animal adoption centre has seen thousands of sick and injured pets come and go - but never anything quite like this.

Treating cats and dogs is second nature to staff at the centre in Thirsk, North Yorkshire, but staff were left baffled after discovering a giant snail more accustomed to Africa nestling on their doorstep.

An African land snail, nicknamed Arnie in honour of its Schwarzenegger-like proportions, was dumped outside the centre over the weekend.

About a year old, Arnie, which is already the size of an outstretched adult hand even though it is only a baby, is settling in to new surroundings and enjoying fame as the centre's strangest resident.

Manager Wendy Ellison found the creature freezing on the doorstep as she took one of the centre's dogs out for an evening walk on Saturday.

It was only through sheer good fortune that it survived for hours in a cardboard box, which had been left with a series of instructions on how it should be fed and kept.

"We are used to getting dogs and cats and other pet animals here, but this little creature is a first for us," said Mrs Ellison.

She has now called for further expert advice on the long-living hermaphrodite creature, which is being kept in a tank heated to a more suitable temperature.

The creatures are known to survive in damp, warm climates on a vegetarian diet and, despite their size, are one of the slowest types of snails in the world. The Blue Cross said it was important owners of such pets were aware of their requirements.

Mrs Ellison said they strongly discouraged people from buying exotic pets when they did not have the knowledge or resources to look after them.