30/06/2005 - The first
phase of a habitat improvement scheme on the
River Wensum at Burgh Common, Swanton Morley,
Norfolk has been completed by the Environment
Agency.
A change to the flow of the river will improve
conditions for a wider range of invertebrates
and aquatic plants to colonise and thrive,
and help to provide increased spawning and
foraging habitat for dace, bullhead, chub,
brown trout, brook lamprey and barbel.
The project involved the creation of two
shallow, fast-flowing gravel riffles between
30 and 40 metres in length to improve the
diversity of the habitat as well as changing
flows in the channel.
In addition, three off-channel bays were
created at the edge of the left bank to improve
the nursery and refuge habitat for young fish
and it is hoped that the diversity of flow
created by the new riffles will further improve
the distribution and variety of fry along
the stretch.
The Agency’s Ecological Appraisal Team are
undertaking monthly fry surveys along the
Swanton Morley stretch to help assess the
impact of the scheme, which also forms part
of a wider programme of fry surveys on the
River Wensum.
Fisheries officer Stephen Lane said: ‘The
scheme should have wider benefits for other
features of the River Wensum which is a Special
Area of Conservation, including white-claw
crayfish and water crowfoot, as well as improving
the food sources available to otters.’
In 1998 the Environment Agency commissioned
the first phase of a wider project concerned
with the rehabilitation of the Wensum, following
concerns from anglers and fisheries specialists
that the value of the River Wensum Fishery
had declined.
Three of the principle reasons identified
in the study for the decline in both the salmonid
and cyprinid fishery of the Wensum were:
Increased sedimentation and loss of spawning
gravels
Loss of nurseries and off-river refuges for
fry
Reduction in the diversity of available habitat
in the main river
A Fisheries Action Plan (FAP) has recently
been completed for the River Wensum, which
identifies a range of prioritised actions
for the Environment Agency, English Nature,
landowners, fishing clubs and other partners
to help address the perceived long term decline
in the fishery.
The scheme at Swanton Morley represents a
significant part of the Agency’s contribution
towards the FAP actions. The scheme also forms
part of a strategic, multi-functional approach
taken by the Environment Agency to improving
the River Wensum and complements other measures
currently underway, such as phosphate stripping
and diffuse pollution reduction.
