Fen Management Handbook - Scottish Natural Heritage

Management of key fen habitat features for invertebrates
Habitat feature Recommended management Key considerations
Permanent and nearpermanent
water,
including emergent
vegetation
Seasonally exposed
marginal sediments
and marginal
vegetation
Temporary pools and
areas of seasonal
flooding
Seepages and
surface flow
Exposed mud/peat
(not at water
margins)
Tall monocotyledondominated
water
margins and swamp
Short and openstructured
vegetation
over wet ground with
little organic litter
Tall continuous
herbaceous
vegetation on damp
soil
Tussocks and tall/
short grassland
mosaics
Scattered trees and
scrub
Old trees and dead
wood
Continuous and
near-continuous
scrub/woodland
with shaded wet
conditions
Rotational and small-scale clearance where
necessary to maintain conditions; water bodies
with grazed margins may need little management,
but some water margins should preferably be
ungrazed to encourage tall marginals, unless
grazing levels are low. Modification of vertical
water margins may be necessary to create gentle
sloping edges or berms.
No specific management needed; varied structure
should be maintained by management of water
bodies and the effects of fluctuating water levels
Avoid tall or shading growth of vegetation during
periods of flooding, preferably by grazing
Maintain reasonably constant conditions; grazing
preferable in open habitats, but level of grazing
critical to maintain open conditions while avoiding
damage by trampling
In grazed sites, trampling should provide sufficient
habitat
Rotational cutting on a varied but preferably long
rotation: with some areas maintained with bare
mud beneath; other areas allowed to develop a
good litter layer. In small sites, management of
small habitat patches may provide sufficient variety
Keep fish-free where possible
Maintain natural fluctuations in water levels
Maintain natural fluctuations in water
levels; ensure constancy of management of
surrounding land
Avoid conversion of flowing to standing
water by ponding back in the interest of
maintaining or increasing water levels;
Important areas are bare, not heavily
trampled and poached, and may be smallscale
in a mosaic with vegetation
Ensure a range of ages present at any one
time; maintain an age range through to very
old and scrub-invaded beds if possible
Grazing Avoid changes in management from grazing
to cutting; the preferred level of grazing
may be determined by the need to maintain
overall structural variety rather than a
uniformly short sward
Rotational cutting; several lengths of rotation
preferable, provided the site is sufficiently large
Grazing at a level to maintain tussocks standing
proud in a shorter sward; assist by cutting
selective tussocks if the balance threatens to shift
Determine acceptable/desirable density, thin if
necessary, and then selectively remove or coppice
scrub/saplings to maintain an approximately steady
state; allow local invasion and ensure continuity of
young growth. Retain a representative mixture of
woody species
Retain trees into old age; avoid surgery or felling
unless absolutely essential. Retain fallen timber on
site. Strategy for replacing trees needs planning
well in advance.
Little management may be needed, depending on
exact circumstances; local thinning of the canopy
may be desirable to vary conditions
Avoid changes in management regime from
cutting to grazing
Ensure good range of growth stages of all
species at all times
Associated fauna best developed where
trees are fairly scattered and exposed
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