No longer cute, no longer washing powder-white, Knut the celebrity bear has become the latest victim of the credit crunch.

Knut, two years old on Friday, is almost ready to mate – but Berlin Zoo is unable to raise the cash for a new polar bear compound that would give him space to romp around and work off some of his raging hormones. So the zoo, which has made millions out of marketing the once-fluffy bear, is looking for another home.

Zoos from across Europe are eager to take on Knut – he is an international star, the only bear to make the cover of Vanity Fair – to boost their ticket revenues. Thousands of Berliners, including intellectuals such as the architect Daniel Libeskind, have started lobbying to keep Knut in the German capital. But when a bear’s got to go, he’s got to go.

“Berlin is set to lose one of its best ambassadors,” said Christian Taenzler, of the tourism authority, “and to the regret of international visitors it is about to lose one of its true icons.”

It has been a bad autumn for Knut. Thomas Doerflein, the keeper who nursed and nannied him during his first year, died suddenly in September. And as the bear grows larger – 210kg (33st) and more than 2.5m (8ft 2in) tall when he stands on his back paws – so his crowd of daily admirers shrinks. His star is on the wane and he has grown more grumpy, less inclined to perform. Animal rights campaigners once claimed that he was becoming addicted to applause and the attentions of his keeper.

Now the clapping is sparse, the keeper is dead and Knut has reverted to normal ursine behaviour, stirring from his morning nap and afternoon siesta only at feeding time. Last year he was given an elaborate birthday cake with a wooden candle, which he promptly ripped apart. This year – a sign of the times – he is to be given a quiche buried in a block of ice.

A new compound and the acquisition of a mate would cost the zoo more than £7 million; too much in a belt-tightening era. Knut’s high-earning days, as the star of feature and documentary films, as the subject of a dozen pop songs and as the standard-bearer of the environmental movement, have faded. “It’s simply too much money. We cannot afford a third group of polar bears in such economically strained times,” a zoo manager said.

The senior bear keeper, Heiner Kloes, agreed. “It’s time for him to go – the sooner he gets a new home the better,” he said. “Anything else would be financially irresponsible.”

The director of the zoo, Bernhard Blaszkiewitz, has been concerned for months that the cult around Knut was overshadowing the rest of the zoo population. He has just published a book, Knautschke, Knut and Co, which argues that the zoo has always been full of other animal personalities and is not dependent on Knut. Knautschke was a hippo who survived the bombings of the Second World War to die at the age of 45 in 1988.

Possible homes for Knut, according to zoo insiders, include Orsa, the Swedish bear park, an animal refuge in Norway and Hanover Zoo. The favourite candidate seems to be Gelsenkirchen Zoo, which has not only a suitable compound but also a polar bear cub called Lara who, at the age of 3, is ready to take on Knut.

Gelsenkirchen’s football team, Schalke, is sponsored by Gazprom and there is speculation that the Russian energy company could help to finance Knut’s transfer too. Needs must: Sigmar Gabriel, the Environment Minister, has withdrawn his official patronage of Knut and thus ended the supply of free fodder. Knut is no longer a suitable symbol, it seems, for the Government’s efforts to slow down the melting of the polar ice-caps. Alice Thomson, page 32

Celebrity animals in Berlin Zoo

— Knautschke, hippo, one of only 91 Berlin zoo animals to have survived the bombardment of the German capital in world war two

— Kosko the elephant presented to East Berlin zoo by Ho Chi Minh (the Vietnamese communist leader, no relation to the panda bear)

— Swampy the loveable alligator, from Mississippi, presented by US soldiers in 1952

— Rike the giraffe, orphaned in a British bombing raid in Novemeber 1943, wounded by shrapnel, evacuated to Vienna, returned to Berlin as a hero in 1953.

— Chi-Chi, panda bear originally intended as a present from China to the US. The US trade embargo intervened and Chi Chi ended up taking the trans-Siberian express from Beijing to Moscow, then on to Berlin.

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