The rediscovery of a fern, long thought to be extinct, is part of a rescue effort to save the plants of the tiny UK overseas territory of Ascension Island in the South Atlantic a fitting success story during the UN's International Year of Biodiversity(1).
During a routine plant survey, a team from Ascension Island's Conservation Department(2) decided to explore an intimidating knife-edge ridge running down the wild southern slopes of Green Mountain, Ascension's dominant volcano. By chance, botanist Dr Phil Lambdon(3) with local Conservation Officer, Stedson Stroud, noticed a tiny fern leaf poking out from an almost bare rock face. They instantly recognized it as the long-lost Ascension Island parsley fern, Anogramma ascensionis. A detailed search soon revealed four minute plants, clinging to a precarious existence in spite of harsh, dry conditions.
The diminutive fern is an attractive plant with delicate, yellow-green leaves, which resemble miniature sprigs of parsley. It has always been restricted to Green Mountain, but was once relatively common according to the description of eminent botanist Sir Joseph Hooker, who visited the island in 1876. Although recorded again in 1889, there were few if any further records until British scientist Eric Duffey collected a specimen on the north side of the mountain in 1958. It was not seen again, and officially declared extinct in 2003. The reasons for the demise are unknown, but it seems likely that competition from more aggressive introduced maidenhair ferns (Adiantum species) is at least partly responsible. Maidenhair ferns have overwhelmed most of the suitable rock ledges on the mountain and devastated the native crevice-living flora.
The rediscovery of Anogramma ascensionis is only the start of a rescue story that has quietly unfolded over recent months. After their early elation, it was clear that the conservation team had to mount a last ditch effort to save the unstable p
|Contact: Bronwyn Friedlander|
Royal Botanic Gardens Kew