Rare butterflies have been returned to a country park after an absence of more than 70 years - where naturalists hope they will once again thrive.
The silver-studded blue is a scarce and delicate species which has been lost from more than 80% of its former habitats in the past century as its heathland habitat disappeared.
Broadland Country Park near Norwich was the original source of butterflies which were introduced to Horsford Rifle Range, Buxton Heath and Kelling Heath, but that population was destroyed in the 1950s when plantation forestry took over.
It is currently found at only four Norfolk locations.
With the trees now removed, heather and black ants, which the butterflies need to complete their life cycle, have returned - and it is hoped - the species should once again thrive in its former home.
The project involved several partners, said Dr Mark Collins, who leads the project for the Norfolk and Norwich Naturalists’ Society.
He added: “This is a protected species, and we had permission from Natural England, as well as vital support from the Norfolk Wildlife Trust, who manage Buxton Heath, and Butterfly Conservation, which has unrivalled experience of such translocations.”The caterpillars are protected from predators and parasites by a species of black ant that takes them down into their nests, where they pupate and over-winter before emerging as adults in June.
“We carried out a detailed survey to ensure that the ants were present in good numbers, and the heather was in good condition for the nectar-feeding adults but it will be a while before we know whether the reintroduction has fully succeeded," said Dr Collins.
Monitoring at the park will continue for at least five years.
Alan Dawson, who monitors the silver-studded blue at Buxton Heath for Butterfly Conservation said: “The butterfly has done very well indeed here, and it was time to take some individuals back to their restored home."Volunteer Dave Weaver said: “With careful management, this will be an important site for nature recovery and biodiversity in Norfolk.
"During a three-year research project with NNNS, more than 2,000 species of plants and animals have been found, and the return of the iconic silver-studded blue to its former home is a moment of great pride to us all."
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