conditions. It is worth considering lowering water levels at times of year when
there is a lack of shallow water available in the surrounding area (Taft et al. 2002).
14.9.5Providing islands and rafts
Nesting areas for terns, gulls, waders, and wildfowl can be created by building
islands. These can be covered in shingle to provide suitable conditions for nest-
ing terns and plovers, but such open conditions are difficult to maintain. One
option is to design islands so that they are covered in water in winter and then
exposed by falling water levels immediately prior to nesting. Winter flooding
helps rot down and disperse any vegetation that might have grown on them.
Otherwise, vegetation might have to be cleared by hand. Islands can be difficult to
construct in deep water and can be subject to rapid erosion by wave action and
to flooding during the breeding season should water levels rise. An alternative is
to provide suitable nesting habitat, for example, for terns, on anchored rafts
(see Burgess and Hirons 1992).
14.9.6Managing reedbeds
Most experience of managing swamps and fens for birds is from managing reed-
dominated vegetation (reedbeds) in Europe, which supports a distinctive assem-
blage of breeding birds (e.g. Hawke and José 1996; Poulin et al. 2002). The
avifauna of reedbeds is strongly influenced by the extent of the swamp/open
water interface, its physical structure and dominant plant species, the duration
and the timing of flooding, and the extent of scrub (Van der Hut 1986; Tyler
1994; Graveland 1998; Poulin et al. 2002).
Management of reedbeds usually concentrates on providing wet, open
reedbed on the margin of open water (water reed). This is because water reed is
the primary habitat for two rare birds in Western Europe, namely Bittern and
Great Reed Warbler Acrocephalus arundinaceus(Tyler 1994; Graveland 1998),
but its extent has declined relative to that of other types of reedbed as a result of
succession, die-back of reed margins, and a lack of suitable shallow open water
into which early successional reed can spread (Tyler 1994; Van der Putten 1997).
Succession in reedbeds can be slowed by cutting or burning. These reduce the
accumulation of litter and raising of the ground surface relative to the water
table, and kill or suppress colonizing scrub. Cutting or burning in winter encour-
ages reed at the expense of other tall plants, while cutting in summer reduces the
dominance of reed relative to other species. Burning is more effective at reducing
litter (Cowie et al. 1992), but many site managers consider it more damaging to
less mobile invertebrates than cutting, despite research showing little or no
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