The River Moidart cSAC
Conservation Strategy
Conserving Natura 2000 Rivers
The River Moidart cSAC Conservation Strategy
Kjersti Birkeland
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Conserving Natura 2000 Rivers. English Nature, Peterborough.
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River Moidart cSAC Conservation Strategy
Conserving Natura 2000 Rivers
This conservation strategy for the River Moidart has been produced as part of Life in UK Rivers, a
project to develop methods for conserving the wildlife and habitats of rivers within the Natura 2000
network of protected European sites.
The project's focus has been the conservation of rivers identified as Special Areas of Conservation
(SACs) and of relevant habitats and species listed in annexes I and II of the European Union Directive
on the Conservation of Natural Habitats and of Wild Fauna and Flora (92/43/EEC) (the Habitats
Directive).
Conservation strategies have been produced for seven SAC rivers in the UK to meet the need for
management plans.The strategies demonstrate how the statutory conservation and environment
agencies have developed conservation objectives, and drawn up action plans with their local partners
for achieving 'favourable conservation status' under the terms of the directive for its listed habitats and
species.
For SAC sites, the directive requires:
z
z
z
Conservation measures to be established that correspond to the ecological requirements of
the annex I and II habitats and species present.
Appropriate steps to avoid the deterioration of habitats and the habitats of species, as well as
the disturbance of the species.
Appropriate assessment – in view of the site's conservation objectives – of the implications of
any plan or project likely to have a significant effect on the SAC.
Each river conservation strategy identifies the conservation measures necessary for its SAC, describes
appropriate safeguards against deterioration or disturbance, and represents an aid to assessing any plan
or project affecting the SAC.
In essence, the strategies set out a management plan for securing conditions whereby a SAC site can
contribute to achieving favourable conservation status for its designated habitats and species at a
national and European level.
To accompany the river conservation strategies, the project has also produced a set of reports collating
the best available information on the ecological requirements of each species and habitat, while a
further series contains advice on monitoring and assessment techniques. Each report has been
compiled by ecologists who are studying these species and habitats in the UK, and has been subject to
peer review, including scrutiny by a Technical Advisory Group established by the project partners. In the
case of the monitoring techniques, further refinement has been accomplished by field-testing and
workshops involving experts and conservation practitioners.
Life in UK Rivers is a demonstration project and, although the reports have no official status in the
implementation of the directive, they are intended as a helpful source of information for organisations
trying to set conservation objectives and to monitor for favourable conservation status for these
habitats and species.
Titles in the Conserving Natura 2000 Rivers ecology and monitoring series are listed inside the back
cover of this report, and copies of these, together with other project publications are available on the
project website: www.riverlife.org.uk.
1
Conserving Natura 2000 Rivers
2
River Moidart cSAC Conservation Strategy
Contents
1 Introduction
5
2 Background
2.1 European context of the designation
2.2 The river conservation strategy
6
6
7
3 The River Moidart cSAC
3.1 Qualifying interest and designated status
3.2 River Moidart catchment and its uses
3.3 The freshwater pearl mussel
8
8
9
11
4 Conservation objectives, ecological requirements and current conditions
4.1 Conservation objectives
4.2 Ecological requirements
4.3 Current conditions in the River Moidart cSAC
13
13
13
17
5 Relevant activities
5.1 Pearl fishing
5.2 Agriculture
5.3 Forestry
5.4 River engineering
5.5 Riparian management
5.6 Domestic discharges
5.7 Road construction, maintenance and drainage
5.8 Aquaculture
5.9 Fisheries management
5.10 Other relevant activities or issues
17
17
17
18
19
20
21
22
22
23
25
6 Monitoring
6.1 Monitoring the freshwater pearl mussel
6.2 Monitoring environmental conditions
26
26
26
7 Management aims and proposed actions
7.1 Water quality
7.2 Flow
7.3 River morphology
7.4 Filamentous algal growth
7.5 Host fish populations
7.6 Awareness
7.7 Research and monitoring needs
28
29
31
32
33
34
35
36
References
38
Appendix A: Abbreviations
40
Appendix B: Competent authorities
41
Appendix C:The ecological requirements of the River Moidart cSAC
42
3
Conserving Natura 2000 Rivers
4
River Moidart cSAC Conservation Strategy
1 Introduction
The River Moidart is of international nature conservation importance for its population of freshwater
pearl mussels (Margaritifera margaritifera). As a result, the river is a candidate Special Area of
Conservation (cSAC).The designation of SACs is obligatory under the Habitats Directive and is used by
the UK government and the European Union to protect endangered species and habitats.The
fundamental reason for designating sites as SACs is to ensure that all parties with an interest in the site
are aware of and take into account the qualifying features and their requirements, in this case the
freshwater pearl mussel. Any activities and operations that may have a significant effect on conditions in
the river should be subject to appropriate assessment and should only be permitted if they are found
to cause no significant damage to the feature of interest, unless it can be demonstrated that there are
imperative reasons of overriding public interest.
This river conservation strategy for the River Moidart cSAC has been produced under Life in UK
Rivers as part of a programme to deliver the objectives of the Habitats Directive.The strategy
establishes a framework for the positive management of the River Moidart in order to safeguard the
long-term survival of the river’s freshwater pearl mussel population.
Kjersti Birkeland/SNH
The River Moidart cSAC is of international importance for its populations of freshwater pearl mussel.
5
Conserving Natura 2000 Rivers
2 Background
2.1 European context of the designation
2.1.1 The Habitats Directive
The River Moidart is a candidate Special Area of Conservation (cSAC), which means it merits special
protection under the Habitats Directive.The directive is one of the main tools through which the
European Union safeguards its natural heritage. It was adopted by the Council of European
Communities on the 21st May 1992 and brought into effect in British law by the Conservation (Natural
Habitats, &c.) Regulations 1994.The directive aims to conserve biodiversity through maintaining and
restoring habitats and species while taking account of economic, social, cultural and regional
requirements.This is achieved through a series of measures, including the creation of a network of
protected sites across Europe, known as Natura 2000, containing specific habitat types (listed in Annex
I of the directive) and vulnerable species (listed in Annex II of the directive).
Sites designated under the Habitat Directive are known as Special Areas of Conservation, but the
network also includes Special Protection Areas (SPAs) designated under the Directive on the
Conservation of Birds (79/409/EEC).The Natura 2000 network aims to maintain the European Union’s
overall biodiversity by ensuring that activities and developments taking place in protected sites are
sustainable for the designated habitats and species.
SACs are initially selected by member states on the basis of the habitats and species present, using
criteria set out in Stage 1 of Annex III to the directive. Once the member state proposes the sites to
the European Commission, those sites are referred to as candidate Special Areas of Conservation.
After adoption by the European Commission these sites become Sites of Community Importance (SCI)
which member states are obliged to designate as SACs as soon as possible thereafter, and at the latest
by 2004. Once identified as a possible SAC, the Scottish Executive’s policy is that the site should be
treated as though it were designated (Scottish Executive, Circular 6/1995, revised June 2000).
2.1.2 Protection of Natura 2000 interest features
The Habitats Directive and Habitats Regulations apply a common protection regime to all Natura 2000
sites (sites selected as SACs and SPAs).The main requirements of the Habitats Directive are:
z
z
z
z
Member states shall establish the necessary conservation measures (for example,
development of appropriate management plans) and appropriate statutory, administrative or
contractual measures which correspond to the ecological requirements of the qualifying
feature(s).
Member states shall take appropriate steps to avoid deterioration of natural habitats, habitats
of species and disturbance of species for which the site has been designated.
Activities, plans or projects, whether within or outside the European site, likely to have
significant effects on the conservation status of the site’s qualifying feature(s) shall be subject
to assessment.The competent authority shall only agree to the plan or project if it is
ascertained it will not adversely affect the integrity of the site, or if there are imperative
reasons of overriding public interest (for example, social and economic reasons).
A surveillance programme of the interest feature(s) should be undertaken, to monitor the
condition of qualifying features and to assess the effectiveness of management measures
undertaken.
2.1.3 The duty of competent authorities
The Habitats Regulations place a duty on the Secretary of State (First Minister) and Scottish Natural
Heritage (SNH), under Regulation 3(2), to exercise their functions related to nature conservation in
accordance with the requirements of the Habitats Directive. Under Regulation 3(4) there is also a duty
on every competent authority in the exercise of any of their functions to have regard to the
6
River Moidart cSAC Conservation Strategy
requirements of the Habitats Directive. Competent authorities are obliged to consult with SNH over
plans and projects that are likely to have a significant effect on a European site, and not to permit
developments or operations unless it can be demonstrated that they will not have an adverse impact
on the integrity of the site or, if they will that there are imperative reasons of overriding public interest
(social and economic) (Regulations 48).
As a matter of policy the government wishes development proposals affecting potential or candidate
European sites to be treated as if the sites had already been classified. According to Regulation 50 it is
also the requirement of competent authorities to review certain existing decisions and consents in
relation to their effects on European sites. Competent authorities are defined in Regulation 6 as
including any minister, government department, public or statutory undertaker, public body of any
description or person holding a public office. A list of relevant competent authorities that have
jurisdiction on and around the River Moidart cSAC is given in Appendix B.
2.1.4 Conservation objectives
An assessment by any competent authority as to whether a plan or a project may have a significant
adverse effect on a site, and therefore should not be permitted to go ahead, must be made against the
site’s conservation objectives.The conservation objectives thus have an important role in delivering the
Habitats Directive in relation to Natura sites – to ensure that there will be no deterioration or
significant disturbance of the qualifying interests based upon their condition at time of formal
identification. In effect, the conservation objectives provide goals for the management of a designated
site, assist in guiding decisions affecting the site and set a baseline for determining whether the site is
being managed in agreement with the requirement of the Habitats Directive.
2.2 The river conservation strategy
The River Moidart cSAC Conservation Strategy aims to establish a management framework to ensure
that the requirements of the river’s interest feature, the freshwater pearl mussel, are taken into account
by those whose activities affect the river and its catchment.The strategy specifically addresses the
management requirements of the freshwater pearl mussel and identifies actions needed to ensure the
maintenance of the freshwater pearl mussel population in the River Moidart. It provides a guide as to
how the river might best be managed in order to optimise the conditions for the pearl mussel in the
long term. In addition to considering management within the cSAC, the strategy considers factors
operating outside the cSAC boundary that potentially impact on the features of interest.
One of the main aims of the strategy is to ensure that the legal obligations are met. An important
factor in this is the setting and application of the conservation objectives. In general, these objectives
require that there is no deterioration in the feature of interest or its habitat (see Section 4.1 for
details).Where appropriate, the strategy also recommends actions extending beyond the legal
requirements of the conservation objectives – for example, where opportunities exist for enhancement
of the feature of interest or where a precautionary approach is deemed appropriate to safeguard
against adverse impacts in the longer term.
The strategy is also committed to taking account of the economic, cultural, social, recreational and
scientific needs of those living and working in the area, and to minimise disruption to all existing legal
activities and interests.The strategy has therefore been developed through interaction and consultation
with all the relevant stakeholders, ensuring that all the relevant issues have been identified and, as far as
possible, that the needs of stakeholder groups have been taken into account.
Although there is a legislative foundation to the protection of SAC sites, the strategy is based on a
voluntary approach between the relevant authorities responsible for implementation, and owners and
occupiers using and having an interest in the area.Whilst this strategy is not a statutory document in
itself it should assist the relevant authorities and stakeholders in fulfilling their statutory responsibilities
as set out in the Habitats Directive.
7
Conserving Natura 2000 Rivers
This strategy aims to complement other plans being developed for the River Moidart area, including the
Site Management Statement for the River Moidart SSSI, and the UK Species Action Plan for the
freshwater pearl mussel. Although the strategy draws some actions from existing plans it also
incorporates further issues and actions of specific relevance to the qualifying interest.
The strategy will be reviewed and amended on a regular basis to ensure that it is kept up to date. Full
account must be taken of future developments in the catchment or new knowledge of the
requirements of freshwater pearl mussels.This first version of the strategy is intended to cover a 10year period, with a review after five years, in 2008/2009.
3 The River Moidart cSAC
3.1 Qualifying interest and designated status
The qualifying interest feature for the River Moidart cSAC is the freshwater pearl mussel (Margaritifera
margaritifera).This species has suffered a drastic decline throughout every part of its Holarctic range,
particularly within the last 50 to 100 years.The decline has been particularly severe in mainland Europe,
England and Wales. Scotland is today considered a European stronghold of the freshwater pearl mussel.
Unfortunately, even in Scotland the freshwater mussel is extinct or in danger of becoming extinct in
two-thirds of rivers occupied by
this species less than 100 years
ago. Undoubtedly, the early cause
of the decline of this species was
linked to destructive pearl fishing.
In recent years, however, a number
of new and significant threats have
arisen, including deteriorated water
quality, degradation of habitat due
to development and river
engineering, and declines of
salmonid host populations.
Being so rare and vulnerable,
protection and enhancement of
remaining freshwater pearl mussel
Sue Scott
populations is considered of
The qualifying interest feature of the River Moidart cSAC is the
national and international
freshwater pearl mussel, which has suffered a drastic decline
importance. In the UK the
throughout most of its range.
vulnerability of the pearl mussel is
recognised by its inclusion on Schedule 5 of the Wildlife and Countryside Act 1981 (as amended),
making it an offence to kill, injure, take or disturb freshwater pearl mussels from any UK river.The
species is recognised as a priority UK Biodiversity Action Plan Species.The freshwater pearl mussel is
considered rare and threatened in Europe and is also listed on annexes II and V of the Habitats
Directive and Appendix III of the Bern Convention.
The River Moidart supports one of the largest and healthiest populations of freshwater pearl mussels
in the UK.The mussel population is also outstanding in a European context, resulting in the River
Moidart’s status as both Site of Special Scientific Interest (SSSI) and candidate Special Area of
Conservation (cSAC).
8
River Moidart cSAC Conservation Strategy
3.2. River Moidart catchment and its uses
3.2.1 Location of the River Moidart and cSAC
The River Moidart is situated 5
km north-east of Acharacle in
Lochaber, Highland.The river is
just over 13 km long, of which
approximately 11 km are
accessible to migratory salmon
and trout.The river is one of two
major salmon rivers flowing into
Loch Moidart.
The cSAC boundary includes the
lower 4 km of the main stem of
the river, from the A861 road
bridge at Kinlochmoidart to the
bridge immediately below Loch
nan Lochan.The cSAC boundary
follows fences, dykes or the road
verge where present. Elsewhere it
lies 10 m back from the edge of
the river channel, where it is
subject to change due to channel
movements.
The River Moidart cSAC
3.2.2 Catchment
The Moidart catchment covers an
area of approximately 42 km2.The
area to the north of the catchment
drains the highest ground, reaching
hills with altitudes up to 882 m.
Steep hill burns (streams) drain a
few small hill lochs within the
catchment.
The River Moidart has fast-flowing
upper reaches while the lower
stretches are slower flowing,
meandering through mixed
woodland, heathland and agricultural
fields.The riverbed is varied with
several pools, riffles and waterfalls,
which give rise to a mixture of
substrate types from boulders to
fine gravel and sand.The river
substrate varies from bedrock to
sand and mud, but is predominantly
composed of cobbles and gravel.
3.2.3 Ownership
The majority of the land within the
Moidart catchment is owned by the
The River Moidart catchment
9
Conserving Natura 2000 Rivers
Kinlochmoidart Estate and Glenmoidart Estate.There are two non-native conifer plantations adjacent
to the river – one is within private ownership while the other is owned by the Highland Council.There
is one grazing tenant within the catchment, and Marine Harvest (Scotland) leases ground for a salmon
hatchery from the Kinlochmoidart Estate.
3.2.4 Use of catchment
The trout and salmon fishing in the river is managed by the two estate owners. Angling on the river is
relatively limited. Most anglers know the river well and fish the river for several days while staying
locally. Some careful pruning of the bankside vegetation is carried out, to allow better casting.The River
Moidart is included as a member of Lochaber and District Salmon Fishery Board (LDSFB).The
Lochaber and District Fisheries Trust (LDFT) biologist assists with the river management and carries
out a quantitative monitoring programme of the salmon and trout population.
Marine Harvest (Scotland) operates a salmon hatchery close to the south bank, approximately 1.4 km
upstream from the A861 road bridge.The hatchery abstracts water from the river at a weir, specifically
constructed for the hatchery, another 700 m upstream (NM731720) and discharges to the river just
below the fish farm (NM723718).
There are two non-native conifer plantations, Brunery Wood and Drynie Hill, adjacent to the river.
Brunery Wood is now due to be felled and the owner’s long-term plan is to develop the area into
native woodland. A small part of Drynie Hill was felled several years ago, in conjunction with the new
road alignment planned for the Kinlochmoidart to Archaracle road.When the construction work starts,
further felling of Drynie Hill woods will take place.
The remaining land adjacent to the cSAC is managed for sheep and cattle grazing.The majority of it is
moorland with some agriculturally improved fields alongside the lower reaches of the river.There is
also some deer stalking in the upper glen.
Around 10 houses take water from the watercourse for their private water supply.
3.2.5 Proposed plans and projects
1: Scottish Water Drinking Water Abstraction
Consideration has been given by Scottish Water to the installation of a public water supply to serve the
Kinlochmoidart area.The proposal is at a very early stage and will have to be appraised on both a
technical and economic basis before a final decision will be reached on whether the proposal will go
ahead.Three different options have been outlined. One includes a new river intake works to be
constructed in the vicinity of the hatchery intake weir at Kinlochmoidart.The second option involves
the extension of the existing water supply from Acharacle, while the third alternative involves a storage
reservoir at Langal, with distribution mains to Kinlochmoidart from this point. All three proposals
could potentially have an impact on the cSAC through, for example, reduced water flow or physical
disturbance of the freshwater pearl mussel, its host species and its habitats during the construction
phase.
2: Native Woodland Grant Scheme
Future plans include replacing the non-native conifers at Brunery Wood with native hardwood, which
could lead to a more diverse habitat and also benefit the ecology of the river.
Special care should be taken during felling and planting to avoid associated adverse impacts.There are
currently no access routes to Brunery Wood and for work vehicles to gain access it will be necessary
to construct either a temporary road through the Loch Moidart and Loch Shiel Woods cSAC or a
temporary bridge over the river.To avoid damage to freshwater pearl mussels, work vehicles should
under no circumstances be allowed to enter the river. Raw concrete must be kept away from the river.
Before felling, forestry drains should be plugged and silt traps installed, in order to avoid silt and debris
leaking into the watercourse. During the planting process use of fertilisers should be avoided in the
riparian area and elsewhere kept to a minimum. Fertilisers should be manually applied and the 4th
edition of the Forestry Commission’s Forests and Water Guidelines should be adhered to.
10
River Moidart cSAC Conservation Strategy
3: New road alignment: Kinlochmoidart – Acharacle
A proposal for a new road alignment between Kinlochmoidart and Acharacle has been put forward by
the transport, environment and communities services of the Highland Council, but it has not been
decided when the work will start. Some trees have already been felled at Drynie Hill to make room for
the new road alignment, and when the construction work starts further felling will take place. As some
works will be adjacent to the cSAC, care must be taken to avoid any adverse impacts during tree felling
and road construction.
3.3 The freshwater pearl mussel
3.3.1 Life cycle
The freshwater pearl mussel life cycle is complex, involving a compulsory stage as a parasite, called a
glochidium (in plural, glochidia), on the gills of either a salmon or trout juvenile (Meyers & Millemann
1977;Young & Williams 1984; Bauer 1987a; Ziuganov et al. 1994). Except for their parasitic phase,
mussels live buried, or partly buried, in sand and gravel in fast-flowing, unpolluted rivers and streams
(Bauer 1988).They reach maturity at about 12 to 15 years of age (Young & Williams 1983, 1984; Bauer
1987a) and if left undisturbed they can live for more than 100 years (Bauer 1992). Freshwater pearl
mussels are capable of moving slowly over the substrate and can rebury themselves in new places if
they become dislodged (Trueman 1968).
The sexes are generally separated into males and females, although hermaphrodism (an individual in
which reproductive organs of both sexes are present) can occur
(Bauer 1987a, Ross 1992), particularly in populations where the
density of freshwater pearl mussels is low (Bauer 1987a). In early
summer the males shed sperm into the water.The female
mussels take in the sperm through their inhalent siphon and
fertilised eggs develop for several weeks in a specialised pouch
on the gills (Lefevre & Curtis 1910; Smith 1979). In mid- to late
summer the gravid females release the tiny glochidia into the
water (Young & Williams 1984, Hastie 2001).
After being shed from the female, the glochidia must acquire a
suitable host within a few days or they will die (Ziugarov et al.
1994). In European rivers, salmon and brown/sea trout are the
only fish species that can act as a host for the glochidia (Young &
Williams 1984; Bauer 1987a; Ziugarov et al. 1994). Upon
encountering a suitable host, the young mussel attaches itself to
the fish’s gills where it becomes encysted (Meyers & Millemann
Mark Young
1977), living and growing as a parasite in an oxygen-rich
Encysted
glochidia
on
host’s
gills.
environment until dropping off the following spring (Bauer 1987a;
Ziugarov et al. 1994).The likelihood of a pearl mussel surviving
long enough to reach this stage is extremely low. It is thought that less than one in a million glochidia
survive to settle on the riverbed as a juvenile pearl mussel (Young & Williams 1984, Bauer 1987a).
Those mussels that do survive and land in a suitable substrate, will burrow down in the sand and, under
the right conditions, live for another 100 years.
The huge losses during the early life stages are compensated for by extremely high fecundity. After
reaching maturity at approximately 10 to 15 years of age, freshwater pearl mussels can continue to
spawn throughout their lifetime. Around 4 million to 5 million larvae are produced at each
reproduction (Young & Williams 1984, Bauer 1987a), and during her lifetime a female mussel can
potentially produce more than 200 million larvae.
The freshwater pearl mussel plays a significant role in natural water purification processes and is
therefore an important species in freshwater ecosystems. Each mussel can filter up to 50 litres of water
per day (Ziugarov et al. 1994).When this water passes through the mantle cavity and over the gills, the
11
Conserving Natura 2000 Rivers
mussel simultaneously takes up the nutrient-rich organic components in the water and secretes
pseudofaeces that are rapidly degraded to harmless products.This way, freshwater mussels are capable
of purifying up to 90% of dissolved material in the water, to the benefit of other animals such as salmon
and trout (Ziugarov et al. 1994).
3.3.2 Ecological requirements
Freshwater pearl mussels seem highly specialised with respect to habitat, but knowledge of their exact
requirements and factors limiting their distribution is incomplete. Certain large-scale macro-habitat
factors, such as riparian vegetation and gradient, are associated with pearl mussel distribution. However,
mussels show a highly aggregated distribution in rivers, indicating that certain microhabitat features are
also of importance (Ross 1988; Beasley 1996; Hastie et al. 2000).
Adult and juvenile mussels seem to have more or less similar habitat preferences, although adult
mussels are found over a wider range of physical conditions (Hastie et al. 2000). Generally, freshwater
mussels are found in fast-flowing water with velocities from 0.1 to 2.0 m s-1. Preferred water depths
seem to range from 0.1 to 2.0 m (Boycott 1936; Bjork 1962; Buddensiek et al. 1993; Hastie et al. 2000),
although mussels are also found in deeper areas and in pools. Availability of suitable substrate is very
important – freshwater pearl mussels prefer stable cobble/boulder-dominated substrate with some fine
sediment that allows the mussels to burrow (Boycott 1936; Bjork 1962; Purser 1985; Bauer 1992).
Changes in flow apart from natural flow processes can be disadvantageous if they conflict with the
pearl mussel’s ecological requirements. Higher flow can remove large numbers of mussels from their
beds (Hastie et al. 2001) and can lead to the scouring out of areas of sand and gravel, or the sorting of
particles in a way that make them less suitable for mussels to become established. Reduced water flow
may also be damaging, often leading to increased water temperature, build-up of fine materials or
filamentous algae on the riverbed, and reduced oxygen availability. Rapid alterations between high and
low flow can be harmful to pearl mussels by dislodging them or leaving them stranded on the river
margins when the water recedes. However, periodic, moderate high-flow conditions in spring can be
valuable as they clear accumulated silt deposits and algal growth, ensuring clean sediments for the
settlement of the juvenile mussels in late spring. In summer, when the young mussel larvae drop from
the fish and settle down in the substrate, flow conditions should be as steady and stable as possible.
High flow at this time may result in glochidia being washed out of the river. Furthermore, young
mussels have relatively fragile and delicate shells and too much abrasion could cause direct damage.
Clean, nutrient-poor water is essential to freshwater pearl mussels and even low levels of persistent
pollution can be lethal (Bauer 1988).The species is particularly sensitive to increased levels of calcium
and to chemical compounds typically associated with enrichment (for example, nitrate and phosphate)
and elevated biological oxygen demand (BOD). Sufficient oxygen is important and juvenile freshwater
pearl mussels can only develop in a stable riverbed substrate that is well mixed with the overlying
water (Bauer 1988). Silt and suspended solids accumulating on mussel beds can be very damaging,
clogging up interstitial spaces in the sediments and preventing oxygen from being transported to the
mussels living there. One-off acute pollution incidents can be just as damaging as persistent, chronic
pollution. Acute pollution incidences may cause immediate death of sensitive species, while chronic
pollution often causes an overall change in the fauna, with sensitive species being replaced by more
pollutant tolerant species. Depending on the type of pollution freshwater pearl mussels can therefore
be affected either directly, or indirectly.
Freshwater pearl mussels are dependent on healthy salmonid populations to complete their life cycle.
The glochidia are parasitic on the gills of salmon and trout, and only larval mussels that find such hosts
will survive.The fish also prevent the glochidia from being washed out of the river with the water
current, and can even provide upstream migration, enabling juvenile mussel to colonise new areas of the
river. Although some older salmon and trout carry glochidia, in the wild it is mainly younger (0+ and
1+) fish that appear to be infected (Karna & Millemann 1978;Young & Williams 1984; Bauer 1987b, c).
The most accepted view is that an immunity to glochidia gradually develops in older fish, as a result of
infections in previous years (Karna & Millemann 1978; Meyers et al. 1980; Bauer 1987a; Bauer et al.
1991; Ziuganov et al. 1994). Due to the crucial relationship between trout and salmon juveniles and the
12
River Moidart cSAC Conservation Strategy
freshwater pearl mussel there is increasing concern over declines in trout and salmon densities in many
rivers.The continuing presence of viable trout/salmon populations is essential for ensuring the
sustainability of the freshwater pearl mussel.
For a detailed description of the freshwater pearl mussel life cycle and ecological requirements see
Skinner et al. (2003), available at www.riverlife.org.uk/species/mussel.html.
4 Conservation objectives, ecological requirements
and current conditions
4.1 Conservation objectives
Conservation objectives are required to ensure that the obligations of the Habitats Directive in
relation to Natura 2000 sites are met – to ensure that there is no deterioration or significant
disturbance of qualifying features.The following conservation objectives have been developed for the
River Moidart cSAC:
To avoid deterioration of the habitat of the freshwater pearl mussel, or significant
disturbance to the freshwater pearl mussel, thus ensuring that the integrity of the site is
maintained and the site makes an appropriate contribution to achieving favourable
conservation status for the freshwater pearl mussel.
In order to determine whether the conservation objectives are being met, it will be important to take
account of those attributes known to contribute to the status of the qualifying feature of interest (in
this case, the freshwater pearl mussel).
For the pearl mussel it will be important to ensure that the following attributes are maintained in the
long-term:
z
The pearl mussel population as a viable component of the site.
z
The distribution of the pearl mussel within the site.
z
The distribution and extent of the habitat supporting the pearl mussel.
z
The structure, function and supporting processes of habitats supporting the pearl mussel.
z
No significant disturbance of the species.
z
z
The distribution and viability of the freshwater pearl mussel’s host species, the Atlantic salmon
(Salmo salar) and brown/sea trout (Salmo trutta).
The structure, function and supporting processes of habitats supporting the pearl mussel’s
host species.
Recent information on the freshwater pearl mussel population in the River Moidart cSAC, its
supporting habitats and host species are, where available, given in Table 1.
4.2 Ecological requirements
To help assess whether the above listed objectives are likely to be met the ecological requirements for
the River Moidart cSAC has been identified, and are set out in an table that:
z
z
Identifies the main ecological requirements of the freshwater pearl mussel.
Where known, provides site-specific targets for important attributes such as water quality
and flow.
13
14
REQUIREMENT
Agriculture, forestry, aquaculture, river
engineering, riparian management,
domestic discharges, road works, hydro
power, abstractions, discharges.
Agriculture, forestry, road works, river
engineering, riparian management,
hydro power, abstractions and
discharges.
Scottish Environment Protection Agency (SEPA) collects and analyses
water samples from the River Moidart, as well as evaluating the water
quality by studies of the invertebrate fauna. Date suggest that the overall
water quality in the river is good, corresponding to SEPA's Water Quality
Class A1. On occasions the water quality immediately below the fish farm
discharge point deteriorates.
Levels should be low and not SEPA measures levels of suspended solids in the River Moidart. Data on
suspended solids are limited, but generally found to be less than 10 mg l-1.
injurious to any life cycle
stage (to be refined by
further studies).
Precautionary target of 10
mg l-1 as annual mean has
been adopted.
Suspended solids
Pearl fishing.
Any activity that may adversely affect
the ecological requirements of the
freshwater pearl mussel or their host
species (see below).
RELEVANT ACTIVITY
Water Quality Class A1
(Scotland)
The freshwater pearl mussel population in the River Moidart has been
investigated on a number of occasions.The most detailed survey is from
1998, when the river main stem, from its mouth up to Loch nan Lochan
(Cosgrove 1999) was examined.This survey showed that the River
Moidart supports a healthy population of the freshwater pearl mussel,
with more than 100,000 mussels scattered throughout the main stem,
where suitable substrates are found (mainly middle to upper regions).
More than 10 mussels per m2 are found in many survey transects.
Juveniles, as well as larger individuals, are found in the river.This contrasts
with most other freshwater pearl mussel rivers, which support
predominantly adult mussels.The proportion of juvenile mussels is
relatively low, suggesting there may be some recruitment problems in the
river.
CONDITIONS IN THE RIVER MOIDART CSAC
Water quality
Habitat extent and water quality
Population density and Population density should be
characteristic for a river
age structure
under conditions of high
physical and chemical quality.
All age classes should be
present.
Population dynamics
ATTRIBUTE
Table 1. Summary of the main ecological requirements of the freshwater pearl mussel, the current conditions in the River Moidart cSAC and activities with a
potential impact on these conditions (see Appendix C for a detailed description of the ecological requirements).
Conserving Natura 2000 Rivers
Targets should be near
background levels for
river; in any case <0.03
mg l-1
Flow regime should be
characteristic of the
river.
Cobble/boulderdominated substrate
with some fine sediment
that allows the pearl
mussel to burrow, but
not leading to clogging
of substrates used by
juveniles or impaired
respiration.
Maintain the
characteristic physical
features of the river
channel, banks and
riparian zone.
Soluble reactive
phosphorus (SRP)
Flow
River substrate
River morphology
The morphology of the river is well maintained.Work to improve the riparian
habitat (i.e. removal of non-native vegetation) is ongoing. In the past, some
engineering work has been undertaken on riverbanks to create grazing fields
and reduce bank erosion and flooding of adjacent land.
River substrates suitable to the freshwater pearl mussel are scattered
throughout the cSAC. Measures of silt and fines covering the top layer of the
riverbed substrate are not available. Silt assessment techniques for rivers
containing freshwater pearl mussels have been developed under the Life in UK
rivers project, but as yet there are no immediate plans to implement such a
monitoring strategy on the River Moidart.
Riparian management, flood alleviation,
river-engineering.
Agriculture, forestry, riparian
management, hydro-power, discharges.
The water flow in the upper reaches of the River Moidart is highly naturalised. Hydro-power, abstraction and
discharges, river-engineering, forestry.
A few households take water from the catchment for their water supply. At
NM731720 a weir has been constructed across the river. From here Marine
Harvest (Scotland) abstracts water for their salmon hatchery, and discharges at
NM723718. The amount of water being abstracted is on average around 90 l -1
but it is not known what % of the daily river flow this constitutes.
Again, SEPA is responsible for measuring SRP levels in the River Moidart. SRP is Agriculture, forestry, aquaculture,
measured in the river by the fish-farm weir, in the discharge water from the fish domestic discharges.
farm, and by the Kinlochmoidart road bridge.While SRP levels in the discharge
water can be very high (>130 mg l-1), SRP levels measured upstream and further
downstream are lower (<0.03 mg l-1) and probably within, or close to the
natural background levels for the river.
River Moidart cSAC Conservation Strategy
15
16
Data on adult salmon and sea trout can be obtained from the catch statistics,
which are maintained by the two estate owners.The catch records are believed
to be accurate and measures of effort are available through records of fishing
lets. Catch data should therefore give a clear indication of fluctuations in the
spawning stock in the river.The data show that in the River Moidart there has
been a drastic decline in the sea trout population during the last decade.Very
few trout juveniles are found in the river during electric-fishing surveys. Juvenile
salmon densities remain abundant.
Fish host populations:
juvenile salmonid
densities (0+ and 1+
year classes)
Illegal pearl fishing is occasionally taking place. In 1998, more than 700 dead pearl-fished shells were found at the edge of
the river. Some smaller incidents have been observed since.
Some in-stream wading for recreational (e.g. angling) and scientific purposes (e.g. electric-fishing) occur.The extent of
these activities are limited and not regarded as damaging to the freshwater pear mussel population.
No disturbance of existing mussel beds by instream activities
Agriculture, forestry, road works, hydro
power, discharges, abstractions, fisheries
management, aquaculture, river
engineering, exploitation, predation.
Agriculture, forestry, aquaculture,
riparian management, domestic
discharges, hydro-power, abstractions,
discharges.
No fishing for pearl mussels.
Absence of rainbow trout and brook trout and Minnows are present in the River Moidart cSAC.
any other non-native species that may impair
juvenile densities of salmon and brown/sea
trout.
Comments
Aim
Translocation is not taking place.
No stocking/translocation of pearl mussel
unless agreed to be in the best interests of the
population.
Environmental disturbance
Densities should be at
or close to natural
carrying capacity for the
river (to be refined by
further studies).
Dense algal growth occurs during spring and summer, particularly in the lower,
slow-flowing reaches of the river, but the extent has not been quantified.
Potential adverse impacts of algal growth on the freshwater pearl mussel
population are unknown.
Extent of filamentous Should be patchy and
not unfavourable to any
algal growth
life-cycle stage (to be
refined by further
studies). Precautionary
target: algal cover should
be <5% over mussel
beds.
Conserving Natura 2000 Rivers
River Moidart cSAC Conservation Strategy
The ecological requirements table is reproduced in Appendix C and has been adapted from the draft
generic freshwater pearl mussel condition guidance produced by the Joint Nature Conservation
Committee (JNCC).
It should be noted that these are for guidance purposes only, and when assessing plans
and impacts the conservation objectives, as in Section 4.1, must be used.
It is expected that some of the targets and ecological requirements in the table will have to be
modified as new knowledge of the full range of physical and biological requirements of freshwater pearl
mussels in UK rivers arises. Used in a manner appropriate to local conditions, however, the table
provides a key tool for evaluating the status of freshwater pearl mussel populations, and for identifying
issues that may adversely impact on those populations and management actions.The table also provides
a guide to the appropriate monitoring strategy required for reporting on the status of the River
Moidart cSAC.
4.3 Current conditions in the River Moidart cSAC
The requirements of the freshwater pearl mussel, as set out in the ecological requirements table in
Appendix C, are compared with current conditions in the River Moidart, and the information set out in
Table 1.This table also identifies activities that, if not carried out in a manner sensitive to the needs of
freshwater pearl mussels, may represent a potential threat to the maintenance or attainment of
conditions favourable to the pearl mussel within the cSAC.These ‘relevant activities’ are considered in
more detail in Section 5 and objectives for management are presented in Section 7.
5 Relevant activities
5.1 Pearl fishing
Mortality due to pearl fishing has been a major cause of decline across the range of the pearl mussel,
leading to its extinction in many rivers. In 1998 the freshwater pearl mussel was given full protection in
the UK under the Wildlife and Countryside Act 1981, making it illegal to kill, take, injure or disturb any
freshwater pearl mussels. Despite this, illegal pearl fishing is still known to occur in many Scottish rivers
and thousands of mussels are killed every year as a result.
The River Moidart is vulnerable to illegal pearl fishing because the river is situated in a sparsely
populated area, is easily accessible by road and contains a large pearl mussel population. In 1998 more
than 700 dead “pearl fished” mussel shells were found on the edge of the river. Further evidence of this
on-going threat was found in the summer of 2001. It seems clear therefore that despite being given full
legal protection illegal pearl fishing remains a threat to the River Moidart freshwater pearl mussel
population.
See Section 7: Actions A6.1, A6.2, A6.3
5.2 Agriculture
Agricultural activities can have significant impacts on rivers and watercourses. Spillage or run-off of
sheep dips and other agro-chemicals can potentially lead to pollution and mortality of a wide range of
aquatic species, including mussels and fish. Ploughing of fields or creation of field drains can increase
run-off of soil into rivers. Heavy grazing can damage bankside vegetation, leading to erosion and
consequent changes in river morphology and substrates. Nutrient run-off, resulting from agricultural
improvements, using lime and fertiliser, may lead to enrichment of watercourses.
The lower stretches of the River Moidart pass through a small area of improved permanent pasture,
17
Conserving Natura 2000 Rivers
used for sheep and cattle
grazing. Fields are fertilised in
the spring and from time to
time ploughed and re-seeded.
There is also sheep and cattle
grazing on open land within the
Moidart catchment, but the
number of grazing animals are
kept relatively low due to the
low productivity and
inaccessible nature of the
ground. A sheep wash, where
sheep dips are applied, is
situated at Glen Forslan,
approximately 2 km upstream
of the upper cSAC boundary.
Kjersti Birkeland/SNH
Grazing animals can have a significant effect on a waterway, causing
bank poaching (above).
Protection of banks from
grazing is considered in Section
5.5.
Given the location of the sheep dip, current careful waste management, relatively low overall grazing
pressure and the small area of improved pasture in the catchment, adverse impacts from agriculture on
the freshwater pearl mussel population in the River Moidart are expected to be minimal. However, due
to the sensitivity of mussels to silt and nutrient-rich water it is important that codes of good practice
are followed.
See Section 7: Actions A1.1, A1.2, A1.3, A1.4, A1.5, A1.10, A1.11, A3.5, A4.1, A6.4,
A6.5
5.3 Forestry
Forestry activity can affect a range of river attributes including water quality, flow, river morphology and
substrate. Although forests generally have beneficial long-term effects on water quality, adverse impacts
are associated with dense commercial conifer plantations.
Ploughing and mounding associated with planting and subsequent felling can lead to increased input of
silt and soil to watercourses, with subsequent changes in water clarity, chemistry and substrate. Normal
forestry practice often requires fertiliser application to recently planted trees, potentially leading to
enrichment. Even operations at some distance from the watercourse can result in such changes.The
potential for longer term acidification of watercourses due to conifers’ production of an acid humus
layer beneath the canopy, caused by air-borne pollution intercepted by the conifers’ foliage, is also well
documented.
Afforestation can also affect the hydrology of streams by increased loss of water through interception
and evaporation from the forest canopy, as well as by increasing flood peaks and lowering water levels
during droughts. Such changes in flows can affect river morphology. Changes to river morphology may
also happen due to direct damage during forestry operations, or by overshading, resulting in loss of
existing riparian vegetation and subsequent bank erosion.Where erosion occurs, inputs of fine
sediments may result.
The majority of the Moidart catchment is heather moorland but there are two small non-native conifer
plantations, Brunery Wood and Drynie Hill, adjacent to the river. Brunery Wood is due for felling and
the present owner has applied for funding through the Woodland Grant Scheme to replace the nonnative conifers with native hardwoods, which may have long-term benefits for water quality in the River
Moidart. Precautions should, however, be taken, particularly during the felling and planting process, to
avoid short-term impacts from forestry operations. Extraction of timber may be particularly difficult in
18
River Moidart cSAC Conservation Strategy
this area as there is no access road or bridge
to the forest area and timber lorries and
large machinery would not be able to travel
beyond the bridge at Brunery. Additionally,
the forest is situated on a steep slope which
may increase the likelihood of run-off packed
with silt, soil and brash entering the river.
The Forests & Water Guidelines should be
strictly adhered to. A new edition (4th) of
these guidelines is presently out to public
consultation and can in due course be
obtained from the Forestry Commission.
Drynie Hill is owned by the Highland
Council. In the late 1990s a small section of
the forest was felled to prepare for a
proposed road alignment from
Kinlochmoidart to Acharacle. During the
felling large amounts of soil and brash
entered the watercourse, with potential
adverse impacts on the water quality. Further
felling, some of which will be adjacent to the
cSAC, is expected to take place when the
road construction work starts.
See Section 7: Actions A1.2, A1.3, A1.6,
A1.7, A1.11, A3.5, A4.1, A6.4, A6.5
Kjersti Birkeland/SNH
Conifer plantations and forestry practices can impact a
river, resulting in silt and fertiliser run-off.
5.4 River engineering
5.4.1 General considerations
River engineering has been responsible for the decline and extinction of a number of freshwater pearl
mussel populations and is a potential threat to mussel populations in many other rivers. Damage
caused by river engineering is typically associated with direct damage to mussels, destruction or
removal of suitable habitat, alteration of water flow, deteriorated water quality or sedimentation.
Engineering works in the Moidart are generally associated either with control of riverbank erosion or
fisheries management.
5.4.2 Flood alleviation
The River Moidart is a high-energy river with rapid fluctuations in water flow. Embankments to confine
water that normally would have spread on to adjacent land and grazing fields have been built along the
lower reaches of the river. Nevertheless, following periods of heavy rainfall the River Moidart
occasionally floods and it is, from time to time, necessary to carry out some flood alleviation work in
the lower section of the river – for example, clearance of ditches and removal of boulders and trees.
Concrete blocks have also been placed against the riverbank of one pool in the river Moidart to try to
prevent bank erosion.
Should it be necessary to carry out further work in order to control the impacts of flooding, such
work needs to be carried out in accordance with the freshwater pearl mussel’s requirements, and
precautions should be taken to avoid adverse impacts in the cSAC. Unfortunately there is little
flexibility in grant schemes available for flood alleviation work and relatively ‘hard’ engineering is often
required to draw down grants.This type of engineering is less likely to be sympathetic to the needs of
mussels than more recent ‘soft’ engineering approaches.
19
Conserving Natura 2000 Rivers
5.4.3 In-stream structures
Appropriate placing of groynes, weirs or gabions can be beneficial, increasing in-stream diversity and
creating or enhancing habitat for fish and freshwater pearl mussels. However, unless extreme caution is
exercised this type of in-stream engineering can have detrimental effects on spawning areas as well as
destroying freshwater pearl mussel habitats, and may lead to increased riverbank erosion.
On the River Moidart limited in-stream engineering, primarily for fishery purposes, has taken place in
the past. Lochaber and District Fisheries Trust (LDFT) is currently undertaking a River Habitat Survey
of the River Moidart; this includes an assessment of the habitat for salmon and trout. Results so far
indicate that the overall fish habitat is generally good, offering a variety of pools and riffles, as well as
spawning gravel substrate.The need for further engineering to improve fish habitat is considered to be
minimal.The riparian owner within the cSAC confirms that she has no interest in carrying out such
activities in the foreseeable future.
5.4.4 Engineering for erosion prevention
Engineering for prevention of bank erosion is considered under Section 5.5.2.
See Section 7: Actions A1.5, A1.13, A1.14, A2.2, A3.6, A5.5, A6.4, A6.5
5.5 Riparian management
5.5.1 General considerations
Appropriate management of riparian areas is essential to maintaining riverbank stability, water quality,
river morphology and in-stream habitats suited to freshwater pearl mussels salmonid. Mismanagement
or inappropriate management of riparian areas can lead to loss of vegetation, severe erosion of
riverbanks, excessive input of fine materials and changes to water quality and substrates.
5.5.2 Erosion
Rivers are dynamic and erosion processes are important to the maintenance of diverse habitats. Some
input of coarse sand and gravel, and the downstream movement of substrates are important to
freshwater pearl mussels and their fish hosts. However, where bank erosion is severe, elevated levels of
silt and sand can cause serious damage to in-stream habitat and the pearl mussels. Activities that can
reduce the stability of the riverbank include changes in land use, removal of bankside trees and
extensive grazing and livestock trampling in the riparian zone. Engineering may also cause or
exacerbate erosion (see Section 5.4).
The riverbanks along the River Moidart are generally stable, supporting a fringe of riparian woodland
along most of the cSAC. However, in the lower reaches, some trees have started to overhang the river
to the point where their centre of gravity is shifting to over the river rather than over the bank, which
can lead to them falling in during flooding.This is undesirable, as resulting breaks in the bank can
become points of bank erosion and sediment input. Overhanging branches can cause eddying and trap
debris during floods, and eroded trees can become caught up in bridge abutments downstream
promoting bridge failure.
In places there is also considerable stock trampling on the riverbank, resulting in poaching of the
vegetation cover on the flood embankment and causes the right riverbank (looking downstream) to
become eroded.To protect these embankments from further damage a management agreement is
presently being developed between SNH, the estate owner and the grazing tenant. By reinstating the
old fence-line livestock will be excluded from the riverbank in the future. Management of riparian trees
will also be undertaken, including riparian planting.
20
River Moidart cSAC Conservation Strategy
5.5.3 Rhododendron control
Rhododendron species are non-native shrubs that can be detrimental to freshwater species, including
the pearl mussel. In the riparian area rhododendrons cast heavy shade, suppressing the bio-production
in aquatic systems. Furthermore, rhododendron leaves take a long time to break down, so their leaflitter provides limited organic input
Rhododendron species (right)
to the watercourse. Rhododendron
can take over a riverbank,
suppresses the regeneration of the
casting heavy shade over the
native trees, shrubs and ground
water and suppressing
flora. In riparian areas the
ground-covering vegetation.
consequent lack of ground cover
In some areas of the Moidart,
rhododendron has recently
can lead to enhanced sediment
been cleared (below).
input into the watercourse.
Dense rhododendron forests have
developed in many places within the
Moidart catchment.To control this
invasive shrub extensive
rhododendron clearing has been
carried out in recent years. Most
rhododendron within the cSAC
boundary have now been cut and
burned, and, in areas away from the
watercourse, treated with
herbicides. High densities of
rhododendron are still found in
riparian areas upstream of the cSAC
boundary. As prevailing winds blow
up the glen, seeds from these
bushes are unlikely to spread and
seed in cleared areas. However, it is
possible that seeds may spread by
river to downstream areas.
Kjersti Birkeland/SNH
Rob Cathcart/English Nature
5.5.4 Bracken control
There is a programme for bracken control within the River Moidart catchment, using aerial application
of asulox. Due to the danger of drift during aerial application and the persistence of asulox in the
environment, SEPA’s guidance to staff for The use of herbicides in or near water and aerial application of
pesticides (May 1998) states that for bracken control by aerial spraying, the buffer strip should be 160 m
around watercourses, which must comply with the standards in the Water Supply (Water Quality)
(Scotland) Regulations 1989.The large buffer strip is also essential to ensure no adverse impacts on the
freshwater pearl mussel.
See Section 7: Actions A1.3, A1.4, A1.8, A1.9, A1.10, A1.11, A1.20, A3.1, A3.2, A3.3,
A3.4, A3.5
5.6 Domestic discharges
Sewage discharges to a watercourse can lead to enrichment and pollution of the water. Freshwater
mussels are very sensitive to such enrichment, as it promotes the growth of algae and plants on the
riverbed.This may restrict the oxygen transport to the sediments where the mussels live as well as
impairing feeding, fertilisation and release of glochidia.
The River Moidart runs though a sparsely populated area and there are currently less than 10 houses
21
Conserving Natura 2000 Rivers
likely to emit domestic discharges into the watercourse. Given the low number of households,
domestic discharges are not considered an important water quality issue at present.
See Section 7: Actions A1.12, A1.18, A1.19, A3.2, A4.4
5.7 Road construction, maintenance and drainage
Work associated with maintenance, improvement and construction of roads can lead to oily products,
road salt, silt, sand or gravel leaking into the watercourse, with direct and indirect adverse effects on
freshwater pearl mussels. Enhanced levels of oil and road salt may affect biochemical and physiological
processes in aquatic species, whilst silt and sand covering interstitial spaces in the sediments could
block the oxygen exchange between free and interstitial water.
The public road from Kinlochmoidart to Glenmoidart runs parallel with the cSAC boundary and
adjoins the cSAC in parts.The Transport, Environment and Community Services of the Highland
Council maintain the road and associated infrastructure, for example, bridges and culverts. Due to the
proximity of the road to the river adverse impacts of road works and drainage could be a potential
threat to the water quality and river substrate in the River Moidart. However, since the road
maintenance work being carried out is limited and no herbicides are used to treat roadside vegetation
adverse impacts on the water quality should be avoided as long as appropriate precautions are taken.
See Section 7: Actions A1.11, A1.15, A1.16, A1.17, A1.18, A3.2, A3.4, A5.1, A5.2, A6.4,
A6.5
5.8 Aquaculture
5.8.1 General considerations
Aquaculture can affect water quality through discharges containing enhanced levels of nutrients, silt,
antibiotics and other chemicals. Unless the discharge water is properly treated this may lead to a
reduction in water quality. Abstraction of water for aquaculture purposes may also adversely affect the
water flow.The potential for transfer of pathogens between farmed and wild fish populations raises
concerns over the health of host salmonid populations.
5.8.2.Water quality
Marine Harvest (Scotland) operates a land-based hatchery unit, situated approximately 1.4 km
upstream from the A861 road bridge at Kinlochmoidart.The fish farm abstracts water from the river at
a weir, specifically constructed for the hatchery, at NM731720 and discharges just below the hatchery
at NM723718.The discharge water has been filtered and passed through settlement ponds and bioblock media prior to discharge. SEPA tests the contents of the discharge water every two months, and
the quality of the discharge water has increased significantly in recent years. Still, on occasions the
nutrient levels in the discharge water can be very high. In spring 2002 substantial growth of sewage
fungus was seen in the immediate areas to the discharge pipe, which corresponded in time to a period
when the fish farm had problems with their filter systems.
Although freshwater mussels are present in the discharge recipient area, mussel densities in this area
are lower than areas upstream and further downstream, despite suitable substrate. It is unknown
whether sub-optimal water quality in this area is a contributing factor to the lower density.
5.8.3 Flows and water abstraction
The fish farm abstraction from NM731720 should not in any 24-hour period exceed 7863 cubic
metres.The abstracted water is discharged back to the river at NM723718.The proportion of river
water being abstracted under different flows is not known, nor is the potential impact this abstraction
may have on the freshwater pearl mussel population, its host species and habitats.
22
River Moidart cSAC Conservation Strategy
5.8.4 Fish health
Transfer of diseases or parasites between farmed and wild salmonids is a potential threat to host
salmonid populations. Potential for transfer of disease exists in both marine and freshwater growing
units. In addition, escapes of farmed salmon threaten the long-term health of wild salmon populations.
Since farmed salmon are genetically different from local salmon stocks, their progeny may be less well
adapted to the river environment into which they are born than the indigenous individuals.This could
lead to reduced overall salmonid productivity in the river, which would consequently adversely affect
the mussel.
Impacts of elevated levels of parasitic sea lice on wild salmonids are well documented.There is strong
evidence that salmon louse larvae produced on marine salmon farms can infect wild salmonids, leading
to increased mortality of salmon and sea trout and premature return of the sea trout post smolts.
There are no marine salmon farms in the immediate vicinity of the River Moidart, although farms
situated in neighbouring areas could potentially have an adverse impact on Moidart salmonid stocks,
through salmon lice infestations and farmed escapees. Studies from Ireland suggest that lice larvae can
drift with the current and infest salmonids more than 20 km away. Heavily lice-infested sea trout postsmolts are regularly caught and seen in the lower reaches of River Moidart. Negotiations between local
fish farmers and wild fish interests, to develop an area agreement for louse management on farmed
fish, are ongoing. Such management agreements will set targets for acceptable lice levels on farmed fish,
which may reduce or eliminate the adverse impacts on wild salmonids. Adverse impacts from farmed
escapees seem to be minimal as few escaped fish are caught on the river.
See Section 7: Actions A1.12, A2.1, A5.1, A5.2, A5.3, A5.4, A6.4, A6.5
5.9 Fisheries management
5.9.1 General considerations
Due to the crucial relationship between freshwater pearl mussels and salmon and trout juveniles, there
is increasing concern over
declines in trout and
salmon densities in many
rivers. Improvements in
the reproductive output
or survival of salmon and
brown/sea trout could
potentially benefit the
freshwater pearl mussel.
An assessment of
activities and operations
which potentially can
affect the salmon and
brown/sea trout
population in the River
Moidart cSAC has
therefore been
undertaken.
5.9.2 Fish passage
As migration barriers can
prevent adult fish from
reaching spawning
grounds, or the ability of
smolts to migrate
Kjersti Birkeland/SNH
Weirs can improve species diversity and habitat, but can also prevent fish
from reaching upstream spawning grounds, reducing the number of potential
hosts for the freshwater pearl mussel.
23
Conserving Natura 2000 Rivers
downstream, they may have a huge indirect impact on the freshwater pearl mussel through a reduction
in the number of available hosts. As part of the River Habitat Survey currently being undertaken by the
Lochaber District Fisheries Trust, fish passage in the River Moidart will be assessed.The main stem and
tributaries will be surveyed, from the river mouth up to where an impassable waterfall is encountered.
Migratory barriers will be recorded and classified as ‘man-made obstacle’ or ‘impassable falls’.
5.9.2.1 Upstream migration
The River Moidart is just over 13 km long, of which approximately 11 km are accessible to migratory
salmon and trout. Along this stretch of the river no obvious barriers to fish upstream-migration have
been seen, although there were some uncertainty as to whether the fish farm abstraction weir could
restrict upstream migration at low water levels. A fish-pass consultant evaluating the weir in winter
2003 concluded that, although the weir could potentially restrict migration at low flows, this was a
minor issue as salmonids in spate rivers, such as the River Moidart, tend to run upstream during
periods of high flow, when the weir did not prevent upstream migrations.
5.9.2.2 Downstream migration
The abstraction offtake pipe was poorly screened and descending smolts and kelts could therefore
enter the offtake.This was not in accordance with the Salmon (Fish Passes and Screens) (Scotland)
Regulations 1994, and a new smolt screen was therefore fitted to the offtake in winter 2003.
5.9.3 Control of diseases and parasites
Parasites or bacterial and viral diseases can get introduced to the catchment with diseased fish, infected
fishing gear, clothes, kayaks or canoes. Depending on the pathogen this could have severe consequences,
and even cause eradication of the infected species (for example, introductions of Gyrodactylus salaris in
Norwegian salmon rivers). All pathogens that lead to a reduction in juvenile densities of salmon and
trout will consequently have a negative impact on the freshwater pearl mussel.
Fishing on the River Moidart and adjacent lochs is limited. The river is mostly fished by anglers that
know the river well and fish for several days, which reduces the likelihood of introducing pathogens to
the river-system. A native sea-trout broodstock programme is presently running on the river and
hatchery-reared trout juveniles are annually being stocked into the river.There is a potential risk of
disease transfer from holding facilities for these fish, as well as from diseased fish kept in the fish farm
at Kinlochmoidart.
5.9.4 Introduction of non-native species
Introduction of fish species not native to the River Moidart, through the use of live bait or stocking
with rainbow trout to enhance fisheries, could have an indirect effect on the freshwater pearl mussels
through the non-native species’ impacts on the trout and salmon population.The introduced species
could be a predator of the native fish, or be an efficient competitor for food and space.
The minnow (Phoxinus phoxinus) is not native to West Scotland but is commonly seen in west Scottish
rivers, including the River Moidart. It is not known how and when minnows were introduced to the
River Moidart but they have frequently been introduced to watercourses through live-bait fishing.
Concern has been raised that minnows are efficient food competitors with trout juveniles,
consequently reducing food resources available for the trout.
5.9.5 Exploitation and recruitment
Information on optimal densities of juvenile salmonids for the freshwater pearl mussel is limited.
However, it seems clear that when densities of suitable hosts decline in a river system, this reduces the
glochidia’s possibility of encountering a suitable host. Hence, salmonid densities in the River Moidart
should be kept as high as possible for the river under natural conditions.
Salmon and sea trout stocks in the River Moidart will be exploited in different ways – for example,
high-seas net fisheries (mixed stocks), coastal fixed nets, by-catches, rods and poaching.With the
exception of high-seas fisheries, which require international co-operation, all other forms of
24
River Moidart cSAC Conservation Strategy
exploitation can potentially be controlled via national legislation.Throughout the UK, considerable
progress in preserving salmon stocks has been made by the Atlantic Salmon Trust and the North
Atlantic Salmon Fund in negotiating the acquisition and subsequent closure of netting stations. Control
of the angling pressure on returning fish is also exercised in a number of rivers by a catch-and-release
policy for rod-caught salmon and trout.There are two owners with fishing rights in the River Moidart;
both practise catch and release almost exclusively. All sea trout are returned to the river, while the odd
salmon may be kept. Angling on the river is also relatively limited.
5.9.6 Stocking to enhance fish populations
Surveys from the River Moidart indicate that there has been a drastic decline in the river’s sea trout
population during recent decades.To enhance the trout population in the River Moidart, a native sea
trout broodstock programme has been developed in a partnership that includes river owners, Marine
Harvest (Scotland) and Lochaber and District Fisheries Trust (LDFT).The first hatchery-reared trout
juveniles were stocked out in the river during spring 2002. LDFT is assessing the progress and success
of the broodstock programme, as well as the continued need for stocking.
5.9.7 Poaching
With the low number of fish presently returning to many west-coast rivers poaching is a potential
problem that needs to be tackled. Poaching from the River Moidart is regarded as minimal and locals
are keeping an eye on the river.The extent of poaching at sea is unknown although illegal nets are
found from time to time. As the River Moidart is within the Lochaber Fishery District the Lochaber
District Salmon Fishery Board (LDSFB) has the authority to provide bailiffs if that should be
considered necessary.
See Section 7: Actions A5.1–A5.11, A6.4, A6.5
5.10 Other relevant activities or issues
5.10.1 Tourism and recreation
Due to its outstanding scenery the area in and adjacent to the River Moidart attracts a high number of
visitors annually.
Such tourism is important to the local economy and provides many local jobs. However, although many
people visit the catchment area, most infrastructure developed to accommodate the visiting guests
(such as hotels, guesthouses and restaurants) is situated in small villages outside the Moidart
catchment. As such, many issues associated with tourist development, such as sewage, wastewater or
hotel development, currently have little impact on the River Moidart freshwater pearl mussel
population.
Visitors’ uses of the area are mainly restricted to angling and walking, although some stalking is also
carried out. By the fish farm weir, people sometimes stop to have a picnic and swim in the river. As
long as care is taken these activities should not have a negative impact on the freshwater pearl mussel
population (however, see 5.10.2).
5.10.2 Confidentiality of freshwater pearl mussel sites
Many freshwater pearl mussel populations have become extinct due to unsustainable pearl fishing.
Protecting the pearl mussel by keeping sites confidential and/or by not attracting people’s attention to
the site can therefore prove advantageous.
The freshwater pearl mussel population in the River Moidart is well known and, in places, can easily be
seen by the casual observer. High densities of mussels occur in areas where people often stop to camp
or have a picnic. From time to time people are seen taking mussels out of the river to have a look at
them. In some instances the mussels are returned to the river, other times they are left on the
riverbank. Interviews suggest that this type of behaviour results from lack of awareness of freshwater
25
Conserving Natura 2000 Rivers
pearl mussels, their vulnerability and their legal protection.
See Section 7: Actions A6.2, A6.3, A6.4, A6.5
6 Monitoring
The purpose of site monitoring is to determine whether the features of interest in the site are in the
desired condition. Practical, generic guidance to be used by the UK conservation agencies for
identification of attributes, targets and monitoring to allow such assessment of cSAC habitats and
species is being developed, and may in due course lead to changes in the monitoring strategy outlined
below. Furthermore, the implementation of the Water Framework Directive will also lead to significant
changes in how environmental data, pressures and impacts are monitored in Scotland.
While awaiting this information, a monitoring strategy for the River Moidart cSAC has been proposed.
This strategy draws largely upon the draft generic guidance (Young et al. 2003), which has been
developed as part of Life in UK rivers to provide standardised methods for:
z
z
z
z
Baseline surveys of unstudied populations.
The assessment of the conservation status of freshwater pearl mussel populations within
individual rivers.
Collecting data for comparison with previous surveys in a monitoring programme.
Collecting data on environmental variables that might influence the status of mussel
populations.
6.1. Monitoring the freshwater pearl mussel
For the monitoring of freshwater pearl mussel populations please refer to Young et al. (2003), which can
be found at www.riverlife.org.uk/species/mussel.html.
For the standardised survey the river should be subdivided into monitoring units based on SERCON
(System for Evaluating Rivers for Conservation) or similar.Within each unit the search for mussels
should start within areas of suitable habitat. If mussels are found to be present within the unit, a survey
of five 50 m transects should be carried out.The transect is worked upstream from the start point, and
using a viewing buckets all mussels that are seen without removing stones or other mussels are
counted in a 1m wide strip. In addition, a 1m2 quadrat is searched more thoroughly at 10, 20, 30, 40 and
50 m intervals, counting both visible and buried mussels.
See Section 7: Actions A7.9
6.2. Monitoring environmental conditions
The freshwater pearl mussel is favoured by certain environmental conditions, such as good water
quality, moderate flows and healthy populations of juvenile salmonids. It may therefore be advantageous
to monitor variables that would indicate or predict unwelcome changes in the environment. Regular
monitoring of environmental parameters may be particularly important for a long-lived species such as
the freshwater pearl mussel, in which maturity is not reached until 10–12 years of age and where
spawning may not take place every year. Hence, conditions in the environment may have been
unfavourable for years without this necessarily being picked up through monitoring of the mussel alone.
6.2.1 Water quality
SEPA is responsible for the monitoring of the water quality of Scottish rivers. In light of the Water
Framework Directive, SEPA’s monitoring policy is currently being reviewed and the establishment of a
revised monitoring programme should be in place by the end of 2006. It is hoped that this monitoring
26
River Moidart cSAC Conservation Strategy
programme will reflect specific
monitoring requirements arising
from the Habitats Directive.
SEPA is currently monitoring the
water quality in the River Moidart
by chemical analyses and biological
invertebrate indicators (‘kicksamples’).Water quality samples are
taken every two months from
upstream of the Marine Harvest
(Scotland) water offtake, from the
discharge water and from 700 m
below the fish farm discharge.
Kjersti Birkeland/SNH
Invertebrate samples are taken
Due to point-source discharges, the Moidart will continue to be
monitored on a regular basis.
twice a year from both upstream
and downstream of the discharge
point. SEPA data indicate that the Moidart has an overall high water quality, well within targets set for
the freshwater pearl mussel. On occasions, however, the water quality deteriorates, and this was
particularly noted before the current water filtering system was installed.
SEPA’s monitoring of the River Moidart is considered adequate and it is recommended that the current
monitoring is continued.When the Water Framework Directive monitoring programmes are
implemented it is suggested that, because of point-source discharges, the River Moidart should be
monitored individually, as it is today, and not as a component of a larger river basin district.
6.2.2 Water flow
Water flow has a major impact on the freshwater pearl mussel both directly and indirectly through its
impact on important features such as riverbed substrate composition, riverbed stability and algal
growth. Regular monitoring will allow the detection of long-term changes in water flow and will
forewarn of the potential knock-on effects of such changes on the pearl mussel.
There is presently no recording of river flow or river level in the River Moidart. In line with the
recommendations made by Young et al. (2003) it is proposed that such monitoring will be carried out in
the future. Electronic data logging will undoubtedly provide the most accurate and detailed data, but
can be costly. A less-inexpensive method would be to install manual measuring-gauges at suitable places
and record water level on a day-to-day basis. Staff at the fish farm may be able to assist with the
reading and SEPA could provide advice on the recommended location and calibration of the gauge.
6.2.3 Monitoring of substrate, and aquatic and riparian vegetation
When the freshwater pearl mussel population is being surveyed, approximately every six years,Young et
al. (2003) suggest that the parameters below should also be monitored for each transect.
z
z
z
z
z
Substrate: An estimate of the percentage area of riverbed covered by each of the
Wentworth scale substrate grades (see Young et al. 2003).
Algal cover:The percentage of filamentous algal mats covering the transect area
Bankside vegetation:The nature and extent of a 20 m width of the vegetation on the river
bank adjacent to, and just upstream of, the transect.
Flow characteristics:The characteristic flow type in the area of the transect, such as ‘glide’
or ‘run’, as defined in the River Habitat Survey protocol.
Other factors known to affect mussels: Target notes should be made of any evidence of
pearl fishing, pollution, use of sheep dips or any other factors known to affect mussel
populations.
27
Conserving Natura 2000 Rivers
6.2.4 Monitoring of fish host populations
Young et al. (2003) also suggest regular monitoring of salmon and trout juveniles in freshwater pearl
mussel SACs. In the River Moidart, Lochaber and District Fisheries Trust (LDFT) biologists have carried
out monitoring of the salmon and trout population since 1997, as part of their surveillance of the
salmonid populations in Lochaber.Within the cSAC there are two electric-fishing stations, but the
frequency these are surveyed varies between years. It is recommended that the LDFT continue their
electri-fishing surveys.The river should be surveyed at least every two years as a minimum. Both prime
and marginal juvenile habitats should be investigated, and it may also be an advantage to increase
numbers of survey sites within the cSAC.
Data on adult fish can be obtained from the catch data maintained by the estate owners.The records
are extensive and would give a good indication of the status of the spawning stock in the river.
See Section 7: Actions A7.9, A7.10, A7.11, A7.12
7 Management aims and proposed actions
Aims for management and proposed actions have been developed to ensure that the River Moidart
cSAC is managed in accordance with the ecological requirements of the freshwater pearl mussel,
ensuring the long-term survival of the species, and thus that the site continues to make a full
contribution to achieving favourable conservation status for the freshwater pearl mussel. Favourable
conservation status is achieved when a feature is maintained in population size and range, and the
conditions for its long-term existence are in place.
In circumstances where there is no absolute evidence for an activity or operation having a negative
impact, but it is reasonable to believe that it will have a negative effect, a precautionary approach has
been adhered to. A number of actions have been proposed, some of which are new while others are
already happening and have been listed to highlight their importance and to ensure that they will
continue to happen. In a few instances, actions that encourage enhancement of the current conditions
in the River Moidart cSAC have been suggested.The three categories of actions are identified in the
following tables as:
z
z
z
28
Required-New: New action, considered essential to maintain current conditions in the River
Moidart cSAC and thus required in light of the Habitats Directive.
Required-Ongoing: Ongoing action, essential to maintain current conditions in the River
Moidart cSAC and thus required in light of the Habitats Directive.
Desirable: New actions that may enhance the conditions in the cSAC but are not required
under the Habitats Directive.
29
*Abbreviations are listed in Appendix A.
SNH, FWAG
FC
FC
Forestry
Forestry
Owner, occupier, SEERAD
SNH
Agriculture, riparian
management
Agriculture, river
engineering
SEPA
Agriculture, forestry,
road work, riparian
management
SNH, SEPA,
Owners &
occupiers
SNH, SEPA,THC
SEERAD
FC, SNH, FWAG,
THC
SEPA
Agriculture, forestry
Others
Owners &
occupiers,
SEERAD, FWAG
FWAG, FC,
SEERAD
Lead
SEPA*
RequiredOngoing
RequiredOngoing
Required-New
Regular
Regular
Short
RequiredOngoing
Required-New
Regular
Regular
Intermediate Desirable
Importance
RequiredOngoing
Time-scale
Regular
Any activity, operation or proposed development to take account of the water quality requirements of the freshwater pearl mussel.
z
Relevant activity
Agriculture
Water quality should comply with SEPA’s Water Quality Class A1.
z
Action
A1.1. Ensure that sheep dip is not used or stored near water and that
newly dipped sheep do not have access to watercourses (see PEPFAA Code
of Good Practice and SE guidance 2003/7).
A1.2. Promote awareness amongst land managers of the need to comply
with legislation on the use and disposal of chemicals used in agriculture
and forestry.
A1.3. Promote best practice and ensure adherence to codes of best
practice for avoiding contaminating watercourses with silt, nutrients and
pesticides from diffuse pollution (see SEPA's Pollution Prevention Guidelines
01,05,09 – information leaflest covering agriculture, diffuse pollution and
habitat enhancement – and the Forestry Commission's Forests & Water
Guidelines).
A1.4.* Reinstate and maintain field fences adjacent to watercourses in
order to prevent poaching of riverbanks and flood embankments by
grazing animals.
A1.5. Encourage more flexibility in existing agri-environmental schemes
(e.g. Rural Stewardship Scheme), and that prescriptions and grant
conditions take account of the freshwater pearl mussel's requirements.
A1.6. Ensure that Forests & Water Guidelines are strictly adhered to during
all forest operations within the catchment.The 4th edition of the
guidelines is presently out to consultation and will in due course replace
the current edition. Adequate supervision of contractors and subcontractors will be required.
A1.7. Any forest scheme should take the necessary precautions to ensure
minimised ground disturbance, which could lead to increased runoffs of
silt and soil to the watercourse. Apply manual mounding and do not use
forest drains.
There should be no deterioration in the current water quality in the River Moidart.
z
Aims for management
7.1 Water quality
River Moidart cSAC Conservation Strategy
30
Riparian
management
Owner,
occupier
Riparian management Owner, occupier,
SNH
A1.10. Establish and maintain a buffer zone between agricultural fields
Riparian
Owner, occupier
and the river. No fertiliser or pesticides should be used or stored within management,
the buffer zone.
agriculture
A1.11. Promote the use of buffer strips and improve the re-generation of Riparian
SNH
native woodland, especially in riparian areas.
management,
agriculture, forestry,
road work,
A1.12. Ensure that water quality requirements/targets for the pearl
Aquaculture,
SEPA
mussel are taken account of when issuing new or reviewing existing
domestic discharges
discharge consents.
A1.13. Promote flood alleviation methods based on ‘soft’ engineering and River engineering
SNH
lobby for increased funding.
A1.14. Establish a code of good practice for river engineering for flood
River engineering,
SEPA
alleviation purposes on the River Moidart.
flood prevention
A1.15. Develop a code of good practice for road construction and
Road work
THC, SEPA
maintenance work adjacent to watercourses.
A1.16. Ensure that pesticides damaging to aquatic life are not used or
Road work
SEPA
stored in or near watercourses.
A1.17. Agree mitigation measures to prevent pollution of watercourses
Road work
THC
from structural roadwork, repair and maintenance.
A1.18. Promote the use of Sustainable Urban Drainage Systems (SUDS) Domestic discharges, SEPA
where development requires the installation of drainage (see SEPA's
road work
guidance Enhancing SUDS for Wildlife)
A1.19. Ensure that any future development is assessed against cumulative Domestic discharges SEPA
impacts on the river (domestic discharges).
A1.9. Remove remaining Rhododendron ponticum and control re-growth.
A1.8.* Maintain bankside trees – especially prune any overhanging
trees in danger of collapsing into the river (see Scottish Native Woods
booklet, Restoring and Managing Riparian Woodlands).
7.1 (continued)
Required-New
Short
Short
Intermediate Required-New
FC
SNH, SEPA,
SEERAD, FWAG
FC, SEPA,
SEERAD, owners
& occupiers
Short
Intermediate RequiredOngoing
SNH, SEPA
THC, SNH
Required-New
Required-New
Regular
THC
Ongoing
Required-New
Short
SEERAD, FWAG,
SEPA,THC
SNH,THC,
SEERAD
SNH
THC, SNH
Intermediate RequiredOngoing
Required-New
Short
Required-New
Regular
SEERAD, SNH
Required-New
Desirable
Regular
SNH
Conserving Natura 2000 Rivers
Relevant activity
Hydropower,
abstraction &
discharges.
River engineering,
flood prevention.
Importance
Required-New
Required-New
Timescale
Regular
Short
Others
SSE, SEPA, SE, SW
THC, SNH,
SEERAD
Lead
SNH
SEPA
Any proposed development to take full account of the flow requirements of the freshwater pearl mussel.
z
Action
A2.1. Any development or activity that would result in altered flow
should be assessed against potential impacts on the pearl mussel, their
habitat and host species.
A2.2. A code of best practice should be followed for works on the river
and riverbank for a) emergencies resulting from flood conditions; b)
procedures for agreeing preventative essential maintenance work c)
regular maintenance of watercourses.
There should be no reduction in the current water flow in the River Moidart.
z
Aims for Management:
7.2 Flow
River Moidart cSAC Conservation Strategy
31
32
Lead
SNH
River engineering
A3.6. All river work should be notified and no work done or substrate
removed from the river until it has been confirmed that freshwater pearl
mussels are absent. If mussels are present and the work considered
essential, the mussels would have to be carefully transferred from the
area, in line with SNH's policy guidance, before starting the work (see
internal guidance for SNH staff: General Guidance on Spey Casework Issues,
with Particular Reference to Freshwater Pearl Mussel). River work should not
be carried out in the salmonid spawning season (September to April).
SEPA
SNH,THC, SW,
SEPA, owners &
occupiers
SEERAD, FC
SNH, FC
SEPA
Riparian management
Riparian management, SNH
agriculture, forestry,
road work, fisheries
management
FC, SEERAD
SNH
THC
Others
Owners &
occupiers
Riparian management
Riparian management, SNH, SEPA
domestic discharges,
road work
Relevant activity
Riparian management
There should be no reduction to the distribution and extent of substrate suitable to the freshwater pearl mussel.
z
Action
A3.1. Ensure long-term management of the riparian zone (including trees,
invasive bracken and non-native species) based on best-practice guidance
(see e.g. Scottish Native Woods booklet, Restoring and Managing Riparian
Woodlands).
A3.2. Ensure that new developments comply with best practice to protect
or enhance the riparian areas and promote the use of Sustainable Urban
Drainage System (SUDS) where the development requires the installation
of drainage.
A3.3.Target funding for continued control of invasive and non-native
vegetation (e.g. Rhododendron, Japanese Knotweed).
A3.4. Aerial application of herbicides, e.g. bracken spraying, should as far
as possible be discouraged and avoided. If aerial application cannot be
avoided a buffer zone of at least 160 m should be adhered to (see SEPA's
staff guidance The use of herbicides in or near water and aerial application of
pesticides, May 1998). Ensure strict adherence to user guidance for all
applications.
A3.5. Encourage better co-ordination of funds used to improve aquatic
and riparian habitats.
The morphology of the river channel, banks and riparian zone should be maintained.
z
Aims for management:
7.3 River morphology
Required-New
Importance
RequiredOngoing
Required-New
Regular
Required-New
Intermediate Desirable
Regular
Intermediate Desirable
Regular
Timescale
Regular
Conserving Natura 2000 Rivers
SNH
SNH
Riparian management
Riparian management
A4.2. Create and maintain buffer zones between the river and adjacent
land to reduce nutrient input (areas to be refined).
A4.3. Create and maintain overhanging riparian vegetation to provide
dappled shade in open areas, and in areas with extensive growth of
filamentous algae.
A4.4. Ensure adoption of best practice for wastewater and sewage
treatment.
Domestic, aquaculture SEPA
Lead
SEPA
Relevant activity
Forestry, agriculture
Action
A4.1. Avoid use of fertiliser in the riparian area. Elsewhere, keep use at a
minimum and follow best practice guidelines (see SEPA guidelines).
Aims for management:
z The extent of filamentous algal growth should not be damaging to any pearl mussel life-cycle stage.
7.4 Filamentous algal growth
Owner &
occupier
Others
SNH, SEERAD,
FC, owner,
occupier
Owners &
occupiers, SEPA,
SEERAD, FC
Owners &
occupiers
Ongoing
Short
Regular
Timescale
Regular
RequiredOngoing
Desirable
RequiredOngoing
Importance
RequiredOngoing
River Moidart cSAC Conservation Strategy
33
34
A5.9. Continue the sea trout brood-stock programme on the river and
assess annually the continued need for stocking.
A5.10. Designate Loch Moidart as a special conservation area for salmon
where no salmon farming should take place.This has also been suggested
by Butler et al. (2001), Review of locational guidelines for the authorisation of
marine fish farms in Scottish waters: Category 4 designations.
A5.11. Consider establishing bailiff force to reduce poaching and improve
policing of the river should that be considered necessary.
Fish passage,
aquaculture,
Fish passage,
aquaculture
River engineering,
fisheries management
A5.3.* Assess fish passage at the Marine Harvest (Scotland) weir and
suggest mitigation if problems exist.
A5.4.* Inspect and maintain smolt screens on Marine Harvest (Scotland)'s
water offtake.
A5.5. Ensure that river engineering for fishery purposes should not take
place in the river unless it can be demonstrated that there will be no
damage to the freshwater pearl mussel and positive benefits to the
salmonid and pearl mussel population.
A5.6. Carry out a health check on hatchery reared fry prior to their
release into the River Moidart.
A5.7. Continue quantifying juvenile salmonid densities through electricfishing surveys.
A5.8. Do not stock using fish not native to the River Moidart.
LDSFB, LDFT,
SEPA
LDFT, Owner &
occupier
LDFT
Owner, occupier
LDSFB
Poaching
Stocking
LDSFB
Marine Harvest,
owner & occupier
Fisheries management SEERAD,
SEPA, SE, SNH,
THC
LDFT, LDSFB
Stocking
LDFT
SEERAD
Required-New
Regular
SNH, SEERAD
Marine Harvest,
LDSFB
Owner, occupier
LDSFB
Required-New
Short
LDFT, SEERAD
LDSFB, SNH
Short
Short
Ongoing
Regular
Regular
Regular
Desirable
RequiredOngoing
RequiredOngoing
Required-New
Required-New
Required-New
Required-New
Short
LDFT, SNH,THC,
SEERAD
Short
Importance
Required-New
Timescale
Ongoing
Others
THC, LDFT, SNH
Lead
Owner &
occupier
LDSFB, owner,
occupier
Fisheries management SNH
Fish health, stocking
Relevant activity
Fish passage, road
work, aquaculture.
Fish passage,
aquaculture, roadwork
Action
A5.1. Inspect river for potential migration barriers, e.g. culverts, baffles,
bridge aprons, water gates.
A5.2. Agree mitigation measures to prevent obstruction to fish migration
from structural repair and maintenance work.
Plans and policies that safeguard and enhance freshwater salmon habitat, access and migration, as well as mitigate against overexploitation and
predation, should be implemented.
The current population of trout of all age classes should be restored up to natural carrying capacity for the river.
z
z
The current populations of salmon of all age classes should be maintained.
z
Aims for management:
z All fisheries management should take full account of the needs of the freshwater pearl mussel.
7.5 Host fish populations
Conserving Natura 2000 Rivers
Regular
Activities identified in
Section 5
SNH,
Rangers
Short
All activities identified Life in UK
in Section 5
Rivers, SNH
Owner & occupier
Ranger, biodiversity Ongoing
officers
SNH,
Short
Owner & occupier
SNH
Timescale
Regular
Pearl fishing,
disturbance
Pearl fishing,
disturbance
Others
Ranger, wildlife
liaison officer
Lead
SNH
Relevant activity
Pearl fishing,
disturbance
Desirable
Required-New
RequiredOngoing
Desirable
Importance
RequiredOngoing
Provide practical advice to owners and occupiers on the sustainable management of the cSAC and land and river in a way that is compatible with
the ecological requirements of the pearl mussel.
Proposed action
A6.1. Improve local protection of the pearl mussel through liaison with
police and local stakeholders. Encourage river users to report pearl
mussel kills or suspicious activity to the police and SNH.
A6.2. Put up interpretation display next to the river, advising about the
pearl mussel's legal protection and vulnerability.
A6.3. Raise awareness of the important role of the pearl mussel in
freshwater ecosystems amongst target local audiences (e.g. anglers,
owner, occupier).
A6.4.* Produce best-practice guidance for the River Moidart freshwater
pearl mussel, focusing on the ecological requirements of mussel. Activities
that may adversely affect the species should be identified and practical
advice on best practice management of river and adjacent land provided.
A6.5. Engage community groups, rangers, etc. though practical projects
that benefit the pearl mussel (e.g. removing fly-tips, pulling up
rhododendron seedlings).
z
Aims for management:
z To reduce incidents that could have an adverse impact on the site by raising awareness of the River Moidart cSAC, the freshwater pearl mussel
and the ecological requirements of the species.
7.6. Awareness
River Moidart cSAC Conservation Strategy
35
36
A7.6. Install water flow/level gauging station on the river to improve understanding of mussel SEPA , SNH
requirements, flow patterns of the river and possible long-term changes in flow and how
flow relates to habitat features.
A7.7. Continue research to establish knowledge of optimal juvenile fish densities, species (i.e. SNH
trout vs. salmon) and age classes for the pearl mussel population in the River Moidart in
addition to the rivers salmonid carrying capacity and required spawning escapement (see
Section 7).
A7.8. Identify champions for promotion and funding of research on the pearl mussel.
SNH
SNH
SNH
Research
Institutes, LDFT
Desirable
Desirable
Short /
intermediate
Intermediate RequiredOngoing
Regular
Intermediate Required-New
Intermediate Required-New
Required-New
Short
SNH
Research
institutes
Research
institutes
Research
institutes
Research
institutes
Required-New
Required-New
Short/
intermediate
Importance
Short
Research
institutes
SNH
Timescale
SNH
Others
Lead
Increased knowledge of optimal flows for the freshwater pearl mussel and relevant habitat features in the River Moidart cSAC.
z
Action
Research:
A7.1. Carry out a survey of the freshwater pearl mussel population in the River Moidart,
with specific reference to the proportion of juvenile mussels and identify whether the
population is functionally recruiting. If assumed to be unsustainable, initiate surveys to
identify limiting factors.
A7.2. Assess the pearl mussel habitat immediately upstream and downstream from the fish
farm discharge with respect to suitability for the freshwater pearl mussel.
A7.3. Undertake a specific River Habitat Survey (RHS) in the cSAC to identify areas suitable
for pearl mussels (according to current knowledge of pearl mussel requirements).
A7.4. Assess the extent and distribution of filamentous algal growth over mussel beds, and
refine tolerance levels.
A7.5. Refine silt tolerance levels for the freshwater pearl mussel.
Increased knowledge of pearl mussel distribution and biology within the River Moidart cSAC.
z
Aims for research and surveying:
7.7. Research and survey needs
Conserving Natura 2000 Rivers
A7.12. Continue monitoring of juvenile and adult salmonids in the River Moidart (see 6.2.4
for details).
Monitoring:
A7.9.The freshwater pearl mussel population, and supporting habitats, in the River Moidart
cSAC should be monitored in accordance with the protocol (Young et al. 2003). For
assessing whether the population is recruiting optimally, return visits should be made on a
6–10 year cycle (see sections 6.1 and 6.2.3 for details).
A7.10. Continue the existing monitoring of water quality in the River Moidart, using
chemistry and biological indicators (see 6.2.1 for details).
A7.11. Monitor the water flow in the River Moidart (see 6.2.2 for details).
Regular
RequiredOngoing
Regular
SEPA
LDFT
RequiredOngoing
Desirable
Regular
SEPA
SNH
RequiredOngoing
Every 6–10
years
SNH
River Moidart cSAC Conservation Strategy
37
Conserving Natura 2000 Rivers
References
Bauer G (1987a). Reproductive strategy of the freshwater pearl mussel Margaritifera margaritifera.
Journal of Animal Ecology 56, 691–704.
Bauer G (1987b).The parasitic stage of the freshwater pearl mussel (Margaritifera margaritifera L.). II.
Susceptibility of brown trout. Arch. Hydrobiol. 76, 403–412.
Bauer G (1987c).The parasitic stage of the freshwater pearl mussel (Margaritifera margaritifera L.). III.
Host relationships. Arch. Hydrobiol. 76, 413–423.
Bauer G (1988).Threats to the freshwater pearl mussel Margaritifera margaritifera L. in Central Europe.
Biological Conservation 45, 239–253.
Bauer G, Hochwald S & Silkenat W (1991). Spatial distribution of freshwater mussels: the role of host
fish and metabolic rate. Freshwater Biology 26, 377–386.
Bauer G (1992).Variation in the life span and size of the freshwater pearl mussel. Journal of Animal
Ecology 61, 425–436.
Beasley CR (1996). The distribution and ecology of the freshwater pearl mussel, Margaritifera margaritifera.
Unpublished PhD thesis. Queen's University of Belfast, Northern Ireland.
Boycott AE (1936).The habitats of the freshwater mollusca in Britain. Journal of Animal Ecology 5,
116–186.
Bjork S (1962). Investigations on Margaritifera margaritifera and Unio crassus: Limnologic studies in rivers
in South Sweden. Acta Limnol. 4, 1–109.
Buddensiek VH, Engel H, Fleischauer-Rossing S & Wachtler K (1993). Studies on the chemistry of
interstitial water taken from defined horizons in the fine sediments of bivalve habitats in several
northern German lowland waters II: Microhabitats of Margaritifera margaritifera L., Unio crassus
(Phillipson) and Unio tumidus (Phillipsson). Arch. Hydrobiol. 127, 151–166.
Cosgrove PJ (1999). Survey of the River Kerry for presence of Freshwater Pearl Mussels (Margaritifera
margaritifera Linn.). Confidential contract report to Scottish Natural Heritage, Kinlochewe.
Hastie LC, Boon PJ & Young MR (2000). Physical microhabitat requirements of the freshwater pearl
mussel, Margaritifera margaritifera (L.). Hydrobiol. 429, 59–71.
Hastie LC (2001). Conservation and Ecology of the Freshwater Pearl Mussel, Margaritifera margaritifera (L.)
Unpublished PhD thesis, University of Aberdeen, Scotland.
Hastie LC, Boon PJ,Young MR & Way S (2001).The effects of a major flood on an endangered
freshwater mussel population. Biological Conservation 98, 107–115.
Karna DW & Millemann RE (1978). Glochidiosis of salmonid fishes. III. Comparative susceptibility to
natural infection with Margaritifera margaritifera (L.) (Pelecypoda: Margaritinidae) and associated
histopathology. J. Parasitol. 64, 528–537.
Lefevre G & Curtis WC (1910). Reproduction and parasitism in the Unionidae. J. Exp. Zool. 9, 79–115.
Meyers TR & Millemann RE (1977). Glochidiosis of salmonid fishes. Comparative susceptibility to
experimental infection with Margaritifera margaritifera (L.) (Pelecypoda: Margaritiferidae). Journal of
Parasitology 63, 728–33.
Meyers TR, Millemann RE & Fustish CA (1980). Glochidiosis of salmonid fishes. IV. Humoral and tissue
responses of Coho and Chinook salmon to experimental infection with Margaritifera margaritifera (L.)
(Pelecypoda: Margaritiferidae). J. Parasitol. 66, 274–281.
Purser GJ (1985). Factors affecting the distribution of the freshwater pearl mussel, Margaritifera margaritifera
(L.), in Britain. Unpublished PhD thesis, University of Aberdeen, Scotland.
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River Moidart cSAC Conservation Strategy
Ross HGC (1988). Studies on the biology of the freshwater pearl mussel Margaritifera margaritifera (L.) in
NW Ireland, with special reference to the life history strategy. Unpublished MSc thesis. Queen's University of
Belfast, Northern Ireland.
Ross HGC (1992).The reproductive biology of the freshwater pearl mussel Margaritifera margaritifera
(L.) in Co. Donegal. Irish Naturalist Journal 24, 43–50.
Smith DG (1979). Marsupial anatomy of the demibranch of Margaritifera margaritifera (Lin.) in north
eastern North America (Pelecypoda: Unionacea). J. Mollusc. Stud. 4, 39–44.
Trueman ER (1968).The locomotion of the freshwater clam Margaritifera margaritifera (Unionacea:
Margaritanidae). Malacologia 6, 401–410.
Young M & Williams J (1983).The status and conservation of the freshwater pearl mussel Margaritifera
margaritifera Linn. In Great Britain. Biological Conservation 25, 35–52.
Young M & Williams J (1984).The reproductive biology of the freshwater pearl mussel in Scotland, I.
Field Studies. Arch. Hydrobiol. 99, 405–422.
Young M, Hastie L & Cooksley SJ (2003). Monitoring the Freshwater Pearl Mussel Margaritifera
margaritifera. Conserving Natura 2000 Rivers Monitoring Series No. 2, English Nature, Peterborough.
Ziuganov V, Zotin A, Nezlin L & Tretiakov V (1994). The freshwater pearl mussel and their relationship with
salmonid fish.VNIRO, Russian Federal Research Institute of Fisheries and Oceanography, Moscow. 104
pp.
39
Conserving Natura 2000 Rivers
Appendix A: Abbreviations
cSAC
Candidate Special Area of Conservation
DSFB
District Salmon Fishery Board
EIA
Environmental Impact Assessment
FC
Forestry Commission
FWAG
Farming and Wildlife Advisory Group
FRS
Fisheries Research Services
JNCC
Joint Nature Conservation Committee
LDFT
Lochaber & District Fisheries Trust
LDSFB
Lochaber and District Salmon Fishery Board
PEPFAA
Prevention of Environmental Pollution from Agricultural Activities
SAC
Special Area of Conservation
SE
Scottish Executive
SEERAD
Scottish Executive Environment and Rural Affairs Department
SEPA
Scottish Environment Protection Agency
SCI
Site of Community Importance
SNH
Scottish Natural Heritage
SPA
Special Protection Area
SSE
Scottish and Southern Energy
SUDS
Surface Urban Drainage System
SW
Scottish Water
THC
The Highland Council
40
River Moidart cSAC Conservation Strategy
Appendix B: Competent authorities
Forestry Commission (FC)
Highland Conservancy,Woodlands, Fodderty Way, Dingwall, Ross-shire IV15 9XB.
Tel: 01349 862144, Fax: 01349 866624.
FC promotes sustainable forestry management through the Scottish Forestry Strategy, in order to
enhance the economic value of Scotland’s forest resources, increase the biodiversity, landscape and
cultural heritage of forests and to offer opportunities for woodland recreation and community
participation.
Lochaber District Salmon Fishery Board (LDSFB)
2 Gray’s Inn, Gray’s Inn, London WC1R 5JH.
LDSFB represents, co-ordinates and promotes the interests of salmon and sea trout fisheries in
Lochaber, and generally takes such steps as may be desirable for the protection, preservation and
development of Lochaber salmon fisheries and having regard for the environment and other fauna and
flora.
Scottish Natural Heritage (SNH)
The Governor’s House,The Parade, Fort William, PH33 6BA.
Tel: 01397 704716, Fax: 01397 700303.
SNH is a government body whose mission is to work with Scotland’s people to care for our natural
heritage.
The Highland Council (THC)
Lochaber House, High Street, Fort William PH33 6EL.
Tel: 01397 703881, Fax:01397 704016.
THC is responsible for carrying out local government functions in the Highlands.
The Scottish Environment Protection Agency (SEPA)
Carr’s Corner Industrial Estate, Lochybridge, Fort William, PH33 6TL.
Tel: 01397 704426, Fax: 01397 705404.
SEPA is responsible for environmental protection in Scotland. SEPA regulates potential pollution of
natural waters and the air and the storage, transportation and disposal of controlled waste and the
keeping of radioactive materials.
The Scottish Executive Environment and Rural Affairs Department (SEERAD)
Government Building, 28 Longman Road, Longman East, Inverness IV1 1SF.
Tel: 01463 34141, Fax: 01463 714697.
SEERAD is responsible for advising ministers on policy relating to agriculture, rural development, food,
the environment and fisheries, and for ensuring the implementation of those policies in Scotland.
41
42
Further guidance on the interpretation of density data in terms of
favourable condition will be produced following testing in 2002 and
2003.
Population profiles should not be attempted where mussel beds are
vulnerable to damage. Further guidance on the interpretation of age
structure data in terms of favourable condition will be produced
following testing in 2002 and 2003.
Generally, water quality should not be injurious to any life stage. A wide
range of water quality parameters can affect the status of interest
features, but standard biological monitoring techniques provide a
reasonably integrated picture in relation to many parameters. All
classified reaches within the site that contain, or should contain,
freshwater pearl mussels under conditions of high environmental quality
should comply with the targets given.The system in Scotland differs
from that used elsewhere in the UK. A scale of five water quality classes
is used (A1, A2, B, C, D) for assessing water chemistry, biology, nutrients,
aesthetic condition, and toxic substances.The overall classification of a
watercourse is given by the lowest class derived from these values. All
classified reaches within the site that contain, or should contain,
freshwater pearl mussels should comply with the targets given.
Refer to the Life in UK Rivers
project standard survey and
monitoring protocol.
Refer to the Life in UK Rivers
project standard survey and
monitoring protocol.
Scotland only – SEPA standard
monitoring protocol.
Annual mean
Annual mean
Should be characteristic for a
river under conditions of high
physical and chemical quality.
Should be characteristic for a
river under conditions of high
physical and chemical quality.
Water Quality Class A1
(Scotland)
Precautionary target
Targets should be set in relation
to river/reach type(s) and should
be near background levels.
*Water quality
(Habitat extent and
quality)
*Water quality:
suspended solids
*Water quality: soluble
reactive phosphorus
Age structure
(Population dynamics)
Elevated levels of suspended solids can clog the respiratory structures of
fish and adversely affect mussel filter-feeding. In the absence of specific
data the precautionary target of 10 mg l-1 (as used for salmon spawning
areas) has been adopted.
Elevated phosphorus levels can result in enhanced plant growth leading
to large diurnal sags in dissolved oxygen levels. SRP target should always
be <0.03 mg l-1.
Comments
Method of assessment
Attribute
* = discretionary
Population density
(Population dynamics)
Targets
The River Moidart cSAC ecological requirements are set out in the table below.The information in this table is based upon generic attributes for the
feature of interest, the freshwater pearl mussel, together with site-specific attributes where these exist. It should be noted that the information in this table
may be subject to change as methods of assessment are developed, and more site-specific information are collected.
Appendix C:The ecological requirements of the River Moidart cSAC
Conserving Natura 2000 Rivers
River morphology
(Habitat extent and
quality)
*River substrate
(Habitat extent and
quality)
Attribute
* = discretionary
*Flow
(Habitat extent and
quality)
Method of assessment
Comments
Flow regime should be
characteristic of the river.
Gauging stations.
River flow affects a range of habitat factors of critical importance to pearl
mussels, including current velocity, water depth, wetted area, substrate
quality, dissolved oxygen levels and water temperature.The maintenance
both of occasional flushing flows and baseflows, based on natural
hydrological processes, is vital. Detailed investigations of habitat-flow
relationships may indicate that a more or less stringent threshold would
be appropriate for a specified reach; however, a precautionary approach
would need to be taken to the use of less stringent values. As a guide, at
least 90% of the naturalised daily mean flow should remain in the river
throughout the year. Naturalised flow is defined as the flow in the
absence of abstractions and discharges.The availability and reliability of
data is patchy - long-term gauged data can be used until adequate
naturalised data become available, although the impact of abstractions on
historical flow records should be considered.
Elevated levels of silt and fine sand can clog substrates used by juvenile
Maintain very little or no silt and Life in UK Rivers has produced
mussels and can impair adult feeding/respiration. Most river SSSIs/ ASSIs
recommendations for assessing
fine sand in substrate
and SACs do not extend to the entire catchment. Some life-cycle stages
siltation in rivers. Quantitative
methods are expensive and will be are potentially susceptible to damage from siltation, the source of which
may lie elsewhere in the catchment outside the site boundary.Where
difficult to link to unclear
there is a perceived risk of damage occurring, or where the species is
ecological requirements of the
already believed to be in decline, a fluvial audit of the catchment is
species.
recommended.This is a relatively new approach developed by fluvial
geomorphologists in the UK; further guidance should be sought from the
appropriate freshwater specialists in the conservation agencies.
Clean, coarse sand is required in stable conditions. In most rivers stability
Assess
%
area
of
riverbed
covered
Maintain the characteristic physical
depends on the presence of cobbles or boulders. See 'Environmental
features of the river channel, banks by each category of the
disturbance' table for comments on engineering works. Extent of
Wentworth scale. Assess river
and riparian zone
overhanging vegetation: this provides shade, keeping water temperatures
morphology usng RHS.
optimal for the species and reducing growths of filamentous algae.
Targets
River Moidart cSAC Conservation Strategy
43
44
Algal mats can impair respiration, feeding, fertilisation and the release of
glochidia. As a guide, should be <5% cover over mussel beds and
potentially suitable areas of coarse substrate.
An abundant supply of juvenile salmonids is vital to the survival of the
larval stage.The relative importance of salmon and migratory and nonmigratory brown trout populations to pearl mussel will vary between
rivers. Physical and chemical conditions need to be suitable for the wellbeing of all life stages of salmonids, including free access up the river and
conditions in the estuary and lower river where the juveniles of
migratory salmonids are present.
See freshwater pearl mussel
monitoring protocol (Young et al.
2003).
Precautionary target
Should be at or close to carrying
capacity of the river (to be refined
following further studies).
Comments
Method of assessment
Targets
Specified assessment method Comment
Objective
Translocation is not generally recommended as a conservation tool. It is
No stocking/translocation of pearl mussel unless agreed to (if appropriate)
a technique that has been little used, and must still be considered
be in the best interests of the population.
experimental. It is also an expensive activity and is likely to be unsuitable
for juvenile mussels.Translocation (if feasible) should therefore be seen as
a last resort. Little work has been undertaken on pearl mussel genetics.
However, given the sedentary nature of pearl mussels, genetically discrete
populations are likely.
Rainbow trout and brook trout are resistant to glochidial infection and
Absence of rainbow trout and brook trout and any other
are not, therefore, suitable host species. Stocking of these species will
non-native species that may impair juvenile densities of
create competition with native salmonids and is likely to reduce host
salmon and brown/sea trout.
opportunities for glochidia.
Pearl mussel fishing is already prohibited under the 1981 Wildlife and
No fishing for pearl mussels.
Countryside Act.
Relevant activities include fishing (wading in the river) and canoeing (at
No disturbance of existing mussel beds by instream
access points to the river). Engineering works that disturb river beds can
activities.
be disastrous for mussel populations, so every effort needs to be made
to leave them undisturbed. As a minimum, existing areas should be
safeguarded, whilst habitat lost through engineering works should be
reinstated.
Aspects of environmental disturbance to be noted as an accompaniment to assessing favourable condition
Attribute
* = discretionary
*Extent of filamentous
algal growth (Habitat
extent and quality)
*Fish host populations:
juvenile salmonid
densities (0+ and 1+
year classes) (Habitat
extent and quality)
Conserving Natura 2000 Rivers
Conserving Natura 2000 Rivers
Ecology Series
1
2
3
4
5
6
7
8
9
10
11
Ecology
Ecology
Ecology
Ecology
Ecology
Ecology
Ecology
Ecology
Ecology
Ecology
Ecology
of the White-clawed Crayfish, Austropotamobius pallipes
of the Freshwater Pearl Mussel, Margaritifera margaritifera
of the Allis and Twaite Shad, Alosa alosa and A. fallax
of the Bullhead, Cottus gobio
of the River, Brook and Sea Lamprey, Lampetra fluviatilis, L. planeri and Petromyzon marinus
of Desmoulin’s Whorl Snail, Vertigo moulinsiana
of the Atlantic Salmon, Salmo salar
of the Southern Damselfly, Coenagrion mercuriale
of the Floating Water-plantain, Luronium natans
of the European Otter, Lutra lutra
of Watercourses Characterised by Ranunculion fluitantis and Callitricho-Batrachion Vegetation
Monitoring Series
1
2
3
4
5
6
7
8
9
10
11
A Monitoring Protocol for the White-clawed Crayfish, Austropotamobius pallipes
A Monitoring Protocol for the Freshwater Pearl Mussel, Margaritifera margaritifera
A Monitoring Protocol for the Allis and Twaite Shad, Alosa alosa and A. fallax
A Monitoring Protocol for the Bullhead, Cottus gobio
A Monitoring Protocol for the River, Brook and Sea Lamprey, Lampetra fluviatilis, L. planeri and
Petromyzon marinus
A Monitoring Protocol for Desmoulin’s Whorl Snail, Vertigo moulinsiana
A Monitoring Protocol for the Atlantic Salmon, Salmo salar
A Monitoring Protocol for the Southern Damselfly, Coenagrion mercuriale
A Monitoring Protocol for the Floating Water-plantain, Luronium natans
A Monitoring Protocol for the European Otter, Lutra lutra
A Monitoring Protocol for Watercourses Characterised by Ranunculion fluitantis and
Callitricho-Batrachion Vegetation
These publications can be obtained from:
The Enquiry Service
English Nature
Northminster House
Peterborough
PE1 1UA
Email: enquiries@english-nature.org.uk
Tel: +44 (0) 1733 455100
Fax: +44 (0) 1733 455103
They can also be downloaded from the project website: www.riverlife.org.uk
The Life in UK Rivers project was established to develop methods for
conserving the wildlife and habitats of rivers within the Natura 2000
network of protected European sites.
Set up by the UK statutory conservation bodies and the European
Commission’s LIFE Nature programme, the project has sought to identify
the ecological requirements of key plants and animals supported by river
Special Areas of Conservation.
In addition, monitoring techniques and conservation strategies have been
developed as practical tools for assessing and maintaining these
internationally important species and habitats.
The River Moidart is of international conservation
importance for its population of the rare freshwater pearl
mussel. Consequently, the river has been
designated as a candidate Special Area of Conservation
under the Habitats Directive.
This conservation strategy aims to establish a
management framework to ensure that the
requirements of the freshwater pearl mussel are
considered when any activity is planned that might affect
the river ecosystem.The strategy also
provides a guide for how the river should be
managed to optimise conditions for the pearl
mussel in the long term.
Information on Conserving Natura 2000 Rivers
and the Life in UK Rivers project can be found at
www.riverlife.org.uk
This document was produced with the support of the European Commission’s LIFE Nature
Programme and published by the Life in UK Rivers project - a joint venture involving English
Nature, the Countryside Council for Wales, the Environment Agency, the Scottish Environment
Protection Agency, Scottish Natural Heritage and the Scotland and Northern Ireland Forum
for Environmental Research.