Two of Britain’s most prominent naturalists joined forces yesterday to set out plans for the world’s largest butterfly sanctuary to protect the species from “catastrophic decline”.

Sir David Attenborough and David Bellamy said that the £25 million project, involving a biodome similar to the Eden Project and 12 gardens over a 27-acre site, was desperately needed to stem the demise of butterflies.

More than three quarters of the 54 species resident in Britain have declined in the past 20 years, with several in severe danger of dying out. Five species of butterfly and 60 moths died out in Britain in just over a century.

Under the new plans set out yesterday, the biodome will be filled with 100,000 tropical butterflies while outside 12 different gardens will be created alongside what are expected to be the richest wildflower meadows in Britain. These will be planted to provide the perfect home for rare species, such as the high brown fritillary, which is now to be found in only a handful of sites.

Butterfly World, which is to be built close to St Albans, was hailed by Sir David as an important step in the move to reverse what he described as an environmental catastrophe.“For the sake of future generations we must take action now,” he said.

Butterfly World is expected to attract a million visitors a year when it is completed in 2011, some 40 per cent of them children, and Dr Bellamy said that it would play a valuable role in teaching the next generation about the importance of butterflies to the environment. “From this starting point we make kids think about what’s happening on a world scale,” he said.

The scheme, which will cost about £25 million to set up, is the brainchild of Clive Farrell, the lepidopterist who pioneered the first walk-in butterfly houses at Syon Park in 1979.

The dome at the new centre, which will be 56ft (17m) high and have a diameter of 328ft (100m), will be the biggest walk-in butterfly house in the world and 10,000 of the insects can be expected to be in the air at any one moment. At least 250 species of tropical butterfly will be released in the dome.

Mr Farrell said: “Butterfly World is designed to bring the public into direct contact with some of the most fragile and beautiful wildlife in the world and send out a clarion call on behalf of this endangered treasure.”

Jeremy Thomas, a professor of ecology at the University of Oxford, said: “Butterflies desperately need our help. They are one of the most sensitive indicators known to science of what is about to happen to nearly all the animals and plants that share their ecosystem.”He cited the loss of habitat as the single most devastating factor in causing butterfly numbers to plummet all over the world, and said some tropical species were driven into extinction before they had even been discovered by scientists. Climate change, urban spread and changes in farming techniques have been blamed for the butterfly’s decline.

About £10 million has been raised towards Butterfly World, which is forecast to earn £123 million in the first five years of operation. Altogether, 10 per cent of profits will be given to environmental, conservation and community projects.

On the wing

Endangered in Britain

High Brown Fritillary Wood White
Pearl-bordered Fritillary White-letter Hairstreak
Duke of Burgundy
Grizzled Skipper
Dingy Skipper Marsh Fritillary
Grayling Silver Studded Blue

Tropical species on view

Giant Atlas moth
Blue Morpho Owl Butterfly
Treenymph Scarlet Swallowtail
Malachite

Source: Butterfly Conservation

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