 Prince Charles, who has called on the world to wake up to the threat of catastrophe from climate change, has been accused of environmental vandalism.  The Duchy of Cornwall, which the Prince of Wales holds in trust and which provides him with an annual income of almost ?18m, was ordered by a court yesterday to hand over environmental data about a controversial oyster farm it owns.  The Duchy of Cornwall Oyster Farm at Port Navas, on the River Helford in Cornwall, cultivates Pacific oysters, a non-native species which local campaigner Michael Bruton believes is damaging the natural habitat of a Special area of Conservation.  Mr Bruton was celebrating yesterday after the First-tier Tribunal on information rights ruled that the Duchy of Cornwall must hand over documents relating to the environmental impact of the oysters on the native wildlife.  The ruling by John angel, the tribunal's principal judge, opens the Duchy to further challenges to its attempts to keep its dealings private, after he declared it to be a public authority rather than a private 