As the building of the animal pens nears completion, the handlers recently found the bodies of two baby wild cats, stung to death by scorpions.

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The cost of such "social protection" is evident in Athens' National Park, where hundreds of wild cats and homeless men live under flowering shrubs, eating from battered tin trays.

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But there has never been conclusive proof there are big cats roaming wild in the countryside.

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Humans have introduced dozens of species into Australia - including wild horses, pigs, goats, dogs, cats, rabbits and foxes - and these have now become a major problem for the ecosystem.

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In the 1980s Beijing established farms to breed the big cats so that they could be released into the wild.

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Sceptics point out that if big cats have been surviving, and breeding, in the wild for all this time, they only have a natural life span of some 20 years.

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