Response of the fen violet, Viola persicifolia Schreber, to different management regimes at Woodalton Fen National Nature Reserve, Cambridgeshire, England

Abstract

The fen violet Viola persicifolia has decreased rapidly in Britain during the last century as a result of drainage and habitat destruction and it is now listed as an endangered species. Data are presented for five years' monitoring of populations existing under contrasting management regimes at Woodwalton Fen National Nature Reserve. This is the beginning of a long-term study which aims to identify management regimes which will allow the retention of healthy populations at Woodwalton, and which could be used to maintain or re-establish healthy populations elsewhere. The maintenance of open fen areas with few competitive species is important for persistence of the fen violet. Natural disturbance (e.g. from falling tress) and a high and fluctuating water table have probably provided this in the past. Annual grazing or mowing regimes may maintain open areas but also encourage competitive monocotyledons.