Fen Management Handbook - Scottish Natural Heritage

species like bittern, and then drop steeply to 2 m to prevent the encroachment of reeds. Hawke
and José (1996) and Merritt (1994) provide further details on the creation and design of reed beds
in addition to their management. In addition to wet reed, it is important when managing reed for
bearded tit to incorporate the preferred nesting site habitat of dry reed with deep reed litter or sedge
undergrowth.
Regular cutting of common reed can be valuable in maintaining stands of pure reed and hence
the specialised bird community associated with the habitat. Where water levels can be controlled,
blocks of reed up to 1-2 ha should be harvested annually between November and February, rotating
the cut area so that any one patch is cut every 5-15 years. Careful burning of degenerated reed
beds during the winter can induce a large new growth of Phragmites the following summer. Where a
reedbed has become too dry through the accumulation of leaf litter, significant bed lowering through
the excavation of the accumulated material can be considered where the phasing and rotation of
such work is compatible with other significant conservation interest.
Monitoring and maintenance of good water quality is critical as excess nutrient enrichment leads to a
loss in the structural qualities of reed, with a lowering of reed density and weak stems. Good water
quality is equally as critical in maintaining optimal food resource availability to water-birds of aquatic
vegetation, invertebrate and fish.
Sensitive periods
Male bitterns may establish their territories as early as February, the breeding season extending to
June. Disturbance within the period February to August should be minimised in respect to bittern and
the other breeding species within this habitat.
Birds of grazed or cut fen in an active floodplain
Habitat features
The features included here are those areas of monocotyledonous plants that resemble floodplain
grazing marsh and wet grassland through grazing or cutting of the fen. With a low or tussocky
vegetation structure outside of late spring and summer and winter flooding, this habitat feature
attracts the same suite of birds as does floodplain and costal grazing marsh.
Recommended management
The management of coastal and floodplain grassland is described in Benstead et al (1997), Merritt
(1994) and Mountford and Cooke (2003) and the principles detailed there apply to fen habitats
when the objective is to manage them to provide a similar vegetation structure, soil conditions and
flooding regime for the same suite of birds.
Sward height and structure and the level of the water table strongly influences the community
of breeding birds such managed fen habitats can support, especially so waders. Lapwing and
Redshank prefer a sward of less than 5cm and 10cm in height respectively, but with a scattering
of tussocks across the field up to 15 cm in height (Youngs 2005). Such tussocks are ideal for
nesting Redshank and Yellow Wagtail, especially when near to shallow pools or footdrains for the
former species. For Snipe and Curlew however, a medium/long sward (15-30cm) interspersed by
shorter areas of sward 5 cm long is the optimum prescription. Heterogeneity of sward height is also
suggested to be beneficial to Yellow Wagtails (Bradbury & Bradter 2003), providing both nesting
and foraging habitat. The sward height of this habitat feature should ideally be maintained from early
March through to late June, by grazing lightly with cattle, at a stocking level of around two cows per
hectare. A low stocking density helps minimise the risk from trampling of eggs and chicks.
Water level management is critical, which for breeding waders needs to be kept within 30cm of
the surface during early March through to late June, so that shallow pools are created in natural
hollows in the ground surface. The approach and end result can be greatly facilitated with the use of
footdrains with shelving or bermed margins to supply and keep water within wet grassland (Smart
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