Fen Management Handbook - Scottish Natural Heritage

maintained by sluice gates within statutory levels. Rivers Agency maintains many
of the existing drains within the site, mainly to reduce the impact of flooding on
surrounding farmland. Although Rivers Agency is interested in de-designating many
of the watercourses within the site, this can only be progressed where farmland
will not be impacted. Ultimately the management of water levels is not within NIEA
control. The management approach is therefore to work within the constraints on
the site and leave the recovery of lowland raised bog sites to other more viable
properties such as at Peatlands Park.
Techniques
In order to replicate the traditions and practices of the area puddling was done by
hand digging between 1997 and 1999. Since 2000 a small digger was brought
in as a less labour intensive means of creating new pools and deepening existing
hollows. In the most extensive area of fen several deeper holes were dug to act
as refuges for invertebrates if water levels dropped really low during prolonged
dry spells. Many of the new pools were isolated from the other long established
ones so nature was given a helping hand by throwing in a few strands of Bog
Pondweed Potamogeton polygonifolius, which helped accelerate establishment.
Irish Damselfly Coenagrion lunulatum has been observed using pondweeds for egg
laying by landing on a leaf and then submerging backwards down the underwater
stem. Emergent stems of species such as Water Horsetail Equisitum fluviatile are
probably used by emerging nymphs and are certainly used for perching by adults.
Establishing the correct vegetative infrastructure in the pools is therefore likely
to be important for invertebrate species.
Monitoring
The site management team do not usually have time to undertake all of the desired
species and habitat monitoring projects, focusing instead on practical work to prevent
the demise of many notable species. Monitoring is therefore mainly of a casual nature
but some measure of success can quickly be determined by peering into the pools to
observe the ongoing development of aquatic vegetation and observing the activities of
the abundant invertebrate life. NIEA undertake SAC/ASSI feature condition monitoring
of Marsh Fritillary and vegetation. Invertebrate monitoring is contracted out to specialist
surveyors. Some ad hoc monitoring is also undertaken by amateurs e.g. counts of Irish
Damselfly.
Plans for the future
Future plans include:
– Creation of more fire breaks by excavating existing pools and if necessary opening
up new ones.
– Continued land acquisition.
– Drainage investigation to improve hydrological understanding of plots and identify
eutrophication risks.
– Continue to work with Rivers Agency to identify drains that can come out of their
watercourse maintenance schedule and be managed purely for nature conservation.
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Experimental scrapes 2007