The plan's goals also include protecting the traces of human habitation on the islands, The Scotsman reported. St. Kilda, in the Outer Hebrides 41 miles west of the nearest island, Benbecula, was inhabited for several thousand years, but the last residents moved to the mainland in 1930 from Hirta, the largest island.
Those signing the management plan include the National Trust for Scotland, which owns the islands, two Scottish government agencies and the British Ministry of Defense. A radar station is located in the islands.
Kate Mavor, head of the National Trust, said the islands have a unique and fragile heritage that includes huge nesting colonies where about 5 percent of European seabirds rear their young, flowers and lichens surviving in tough conditions and including species unique to St. Kilda and the feral Soay sheep, "living relics of livestock from the Iron Age."
"It is for these reasons that St. Kilda is not only treasured by Scotland but by the world and we have a supreme obligation to conserve and protect it for all," she added.
UNESCO, the U.N. cultural agency, recognizes St. Kilda as a world heritage site for its natural environment, cultural history and marine environment.