Walker inspected the giant red love heart, scented with some of his favourite treats, which was hung from a tree in his enclosure with a note reading: "Can't bear it without u?".

The 63-stone bear then ripped the card down, threw it into his pond and dived in after it.

Three-year-old Walker, who lives in Highland Wildlife Park in Inverness-shire, is expected to be paired with a mate by the end of the year.

Daska Macintosh, visitor services manager at the park, said: "Walker has become a bit of a celebrity at Highland Wildlife Park and, as with most well-known personalities, he's received a small, well actually quite big, love token from his secret Valentine.

"We'd be delighted to get our well-loved bear loved-up himself before the end of the year with a mate but we're hoping that this heart coated with some of Walker's favourite goodies will do the trick in the meantime and get him feeling the love this Valentine's Day."

Douglas Richardson, animal collection manager, said: "He is three years old now but won't be fully mature for another two or three years, and we hope to get him settled with a female of a similar age as soon as we can.

"Because Rhenen Zoo, where he was born, has been so successful in breeding and rearing polar bears, quite a few of the available females around Europe are rather too closely related to him, and so he is not spoilt for choice.

"Although he is still too young to breed, it is important that he and his future mate have time to get used to each other.

"On a different note, Walker is still at the very playful stage and it is our opinion that he would benefit from a suitable wrestling partner."