Chilly reception for a new polar bear

• In the swim: Walker decides he's safer in the water Pictures: Jeff J Mitchell/Getty

But when her new companion finally arrived at the Highland Wildlife Park yesterday, the two animals turned out to be polar opposites.

The 28-year-old bear appeared less than impressed when her new 23-month-old male companion, called Walker, was introduced to the enclosure for the first time.

She has not had another polar bear companion since her partner Barney died at Edinburgh Zoo in 1996, and for the past five years she has been the only polar bear in Britain.

Douglas Richardson, animal collection manager at the park, said: "Mercedes was initially not overly impressed by the appearance of the younger bear and expected her to try to teach the youth some manners. He is desperate to play but she would quite like to rip his head off."

Visitors to the park near Kingussie watched as Mercedes and Walker repeatedly squared up to each other within a few inches and roared.

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However, Mr Richardson said: "It is what we would expect a polar bear to do. People think having an animal on its own is terrible, but most species of mammal are solitary.

"Female polar bears might let males near them when they are on heat but for most of the time they are not interested."

Mr Richardson said Walker was already becoming popular with park visitors.

"Mercedes really just mooches around, but he is on the go non-stop. People are seeing a young polar bear at play and they love it."

Walker's favourite toys are traffic cones and stands used to prop up umbrellas.

The male polar bear, who arrived in the UK from Holland's Rhenen Zoo earlier this month, will become the park's breeding male once he matures in two or three years' time.

Mercedes, who gave birth to two cubs with her partner Barney while at Edinburgh, is now too old for breeding.

Mr Richardson said breeding polar bears in captivity may prove to be crucial in ensuring the long-term survival of the species in the wild.

"Ten years ago there was not intention for the Royal Zoological Society to keep polar bears after Mercedes," he said. "But since then the issue of climate change has come to the fore. Polar bears will be one of the first major species affected, which means there is an increased importance for good zoos which handle polar bears well."

He said the colony of polar bears in West Hudson Bay in Canada, where Mercedes was born, will be one of the first threatened with extinction.