Action Plan: Fen, Marsh & Swamp

Fen, marsh and swamp are vegetated, non-woodland, habitats that are groundwater fed and either permanently, seasonally or periodically waterlogged, on peat, peaty or mineral soils where grasses do not predominate. Fens are dynamic semi-natural systems and in general, management is needed to maintain open-fen communities and their associated species richness. Without appropriate management (e.g. mowing, grazing, burning, peat cutting, scrub clearance), natural succession will lead to scrub and woodland forming.

Fen habitats support a diversity of plant and animal communities. Some can contain up to 550 species of higher plants, a third of our native plant species; up to and occasionally more than half the UK’s species of dragonflies, several thousand other insect species, as well as being an important habitat for a range of aquatic beetles. In comparison, swamps tend to be species poor, generally dominated by bulk emergent plants, with very uneven knowledge of the floristic and environmental relationships. These habitat types are associated with locally important species including: whooper swan, hen harrier, water shrew, short eared owl, harvest mouse, bog rosemary and small pearl-bordered fritillary.