Sound of Arisaig (Loch Ailort to Loch Ceann Traigh) Sac

Conservation and Management Advice

SOUND OF ARISAIG (LOCH AILORT TO LOCH CEANN TRAIGH) SAC

MARCH 2021

This document provides advice to Public Authorities and stakeholders about the activities that may affect the protected features of Sound of Arisaig Special Area of Conservation (SAC). It provides advice from Scottish Natural Heritage (SNH) (operating under the name of and hereinafter referred to as NatureScot) under Regulation 33(2) of the Conservation (Natural Habitats, &c.) Regulations 1994 (as amended in Scotland) to other relevant authorities about any activities/operations which may cause deterioration of the habitats or species, or disturbance of species protected in the SAC, and the Conservation Objectives for the site. It covers a range of different activities and developments but is not exhaustive. It focuses on where there is a risk to achieving the Conservation Objectives. The paper does not attempt to cover all possible future activities or eventualities (e.g. as a result of accidents), and does not consider cumulative effects.

Further information on marine protected areas and management is available at - https://www.gov.scot/policies/marine-environment/marine-protected-areas/ For the full range of MPA site documents and more on the fascinating range of marine life to be found in Scotland’s seas, please visit - www.nature.scot/mpas or https://jncc.gov.uk/advice/marine-protected-areas/

Document version control

Version Date Author Reason / Comments 1 01/08/2018 Laura Steel 1st draft. 2 09/03/2020 Sarah Review and edit. Cunningham 3 30/03/2020 Sarah Review of Corrina’s comments. Cunningham 4 31/03/2020 Emma Philip Review before sign-off 5 21/09/2020 Katherine Rebranding and text formatting Smailes

Distribution list

Format Version Issue date Issued to Electronic 1 09/03/2020 Corrina Mertens Electronic 2 31/03/2020 Greg Mudge and Chris Donald

Contents 1 OVERVIEW OF DOCUMENT ...... 4 2 INTRODUCTION ...... 4 2.1 Purpose statement ...... 4 2.2 Conservation benefits ...... 4 2.3 Wider benefits ...... 4 2.4 Contribution to policy commitments ...... 7 3 ROLES ...... 7 4 PROTECTED FEATURES AND STATUS ...... 8 5 SETTING CONSERVATION OBJECTIVES ...... 10 5.1 Background ...... 10 5.2 Relationship between feature condition and Conservation Objectives ...... 10 5.3 Overlapping Marine Protected Areas boundaries ...... 10 6 FEATURE SENSITIVITY ...... 10 6.1 Subtidal sandbanks ...... 11 7 MANAGEMENT ...... 11 7.1 Conservation Measures ...... 11 7.2 Advice to support management ...... 11 7.3 Best Practice ...... 12 TABLE 2. NATURESCOT’S ADVICE TO SUPPORT MANAGEMENT FOR SOUND OF ARISAIG SAC FOR ACTIVITIES WHICH ARE CONSIDERED CAPABLE OF AFFECTING THE PROTECTED FEATURES...... 13 TABLE 3. ACTIVITIES THAT ARE CONSIDERED NOT LIKELY TO AFFECT THE PROTECTED FEATURES (OTHER THAN INSIGNIFICANTLY) ...... 15 8 RESEARCH AND SURVEY REQUIREMENTS ...... 15 ANNEX 1. SOUND OF ARISAIG SAC CONSERVATION OBJECTIVES ...... 16 ANNEX 2. SUPPORTING INFORMATION ...... 27 Factors limiting the recovery of features ...... 27 ANNEX 3. GLOSSARY FOR CONSERVATION OBJECTIVES ...... 28 REFERENCES ...... 30

1 Overview of document This document provides details of the conservation and management advice for Sound of Arisaig Special Area of Conservation (SAC) and it is divided into eight main sections. The introduction in section 2 gives an overview of Sound of Arisaig SAC and its contribution in terms of conservation and wider benefits. Section 3 provides an overview of the roles of the various bodies involved with advising, regulating and managing the marine protected area. Section 4 describes the protected features and their condition, and section 5 introduces the Conservation Objectives for the site. Section 6 describes the threats and pressures to which the protected features are sensitive, and section 7 provides the management advice for these activities. Section 8 identifies what further research and surveys may be required to increase our understanding of how the protected features utilise the site for which they are designated.

Throughout this document the term Special Area of Conservation (SAC) is used in relation to the site name, e.g. Arisaig SAC or in discussion of the specific legislation relating to the site. Otherwise the term Marine Protected Area (MPA) is used when discussing the site or the MPA network generally. The term qualifying features is used in the Conservation Objectives (Annex 1) to refer to habitats and species that the Arisaig SAC has specifically been designated to protect. Within the wider document text, the term protected features is used to refer both to these specific site features and more generally to species or habitats protected through MPA designations.

2 Introduction

2.1 Purpose statement Sound of Arisaig SAC has been designated to protect subtidal sandbanks. By doing so it contributes to the Scottish, UK and OSPAR MPA networks, the conservation of the wider marine environment around Scotland, and progress towards Good Environmental Status within the North-East Atlantic marine region. The main purpose of Sound of Arisaig SAC is to help restore subtidal sandbanks in favourable conservation status in the Atlantic Biogeographic Region.

2.2 Conservation benefits Sound of Arisaig SAC provides conservation benefits by affording protection to subtidal sandbanks and their associated species. In summary the conservation benefits of this designation are:

 The protection of the subtidal sandbanks which have an unusually high diversity of representative sublittoral sediment habitats within a relatively small area.  The protection of extensive maerl beds and seagrass beds, both of which are OSPAR threatened and declining habitats that harbour rich associated communities and can be important nursery grounds for fish and shellfish.

2.3 Wider benefits Sound of Arisaig’s subtidal sandbanks provide ecosystem services locally and to the wider marine ecosystem. We describe these ecosystem services in terms of their functions (the support or provision of something to the wider ecosystem e.g. habitat, nutrient cycling, sediment stabilisation) and natural resources (e.g. fish and shellfish, aggregates, wildlife), which in turn lead to benefits for people.

Figure 1 illustrates how the protected feature of Sound of Arisaig SAC contribute to benefits for people.

The functions associated with the subtidal sandbanks of Sound of Arisaig SAC are described in Annex 1, Table 2b as part of the site’s Conservation Objectives. This outlines how the protected feature contributes to the functions described. The feature, especially when taken within the context of the whole MPA and/or local ecosystem, contributes to certain functions more than others, e.g. the formation of a physical barrier and supporting connectivity. The functions of the protected feature are fundamental to the continued supply of natural resources and benefits associated with this MPA, and to the long-term health of the protected features.

Sound of Arisaig SAC contains diverse marine habitats that support a variety of natural resources. The fish and shellfish (including juveniles), and seaweeds living within the MPA that can be harvested by humans or utilised by other marine species, are the most obvious resource. The MPA supports wildlife including bird and mammal species. The sandbanks of the Sound of Arisaig also supply sandy sediment to the beaches of the area that are important for recreational enjoyment and local tourism.

The Sound of Arisaig SAC is an area that benefits people locally via fishing and shellfish gathering. It is provides a location where people can engage in outside pursuits for health and wellbeing e.g. sailing and walking, and is home to wildlife and habitats that can be watched, enjoyed and studied. It is a place where communities and visitors can spend time connecting with and enjoying nature.

The benefits that arise from the functions and natural resources of the MPA are typically small in the context of the whole of Scotland, but some are of greater importance for this MPA and the people that use it. There is potential for benefits to be enhanced. This may be achieved by improving the quantity or quality (health) of the protected feature and/or through promoting, for example, more recreational enjoyment or use of natural resources that is compatible with the site’s Conservation Objectives.

Figure 1. Benefits to people associated with the protected feature of Sound of Arisaig SAC. 6

2.4 Contribution to policy commitments Managing this SAC to maintain subtidal sandbanks in favourable condition, will ensure the continued provision of the benefits above as well as the site’s contribution to:

 An ecologically coherent network of MPAs which are well managed under the OSPAR convention and national legislation.  Achieving Favourable Conservation Status for subtidal sandbanks under the EU Habitats Directive.  The protection of maerl beds and Zostera beds which are OSPAR threatened and declining habitats.  Progress towards achieving Good Environmental Status particularly in relation to biological diversity and seafloor integrity.  Making a significant contribution to the protection, enhancement and health of the marine area under the National Marine Plan.  Restoring marine and coastal ecosystems and increasing the environmental status of our seas under the Scottish Biodiversity Strategy.  Helping to adapt to climate change under The Scottish Climate Change Adaptation Programme.

3 Roles This document provides advice for Sound of Arisaig SAC in relation to activities that may affect the protected feature. More detailed advice can be provided to public authorities to inform their decision making as required. In doing this, our aim is to ensure the Conservation Objectives for the SAC are met.

The Conservation (Natural Habitats, &c.) Regulations 1994 (as amended in Scotland) (hereafter referred to as the Habitats Regulations) transpose the EC Habitats Directive into domestic legislation. Regulation 33(2) gives NatureScot a statutory responsibility to advise other relevant authorities about any activities/operations which may cause deterioration of the habitats or species, or disturbance of species protected in the SAC, and the Conservation Objectives of the site.

It is the role of the relevant and competent authorities1 to ensure that the activities they regulate, permit or license do not risk the achievement of the Conservation Objectives of Sound of Arisaig SAC. The management advice in this document is provided to assist authorities in managing the activities outlined in Annex 2 and undertaking Habitats Regulations Appraisals of plans and projects.

Stakeholders can provide additional evidence to support the development of management including local knowledge of the environment and of activities. This will contribute to the development of well-designed and effective management measures.

1 Relevant authorities are defined in Regulation 5 of the Habitats Regulations and encompass those authorities that have functions in relation to land/water within or adjacent to a European Marine Site (includes marine SACs). They are nature conservation bodies, local authorities, water undertakers, navigation authorities, harbour authorities, lighthouse authorities, SEPA, district salmon fishery board and, National Park Authorities and local fisheries committees. Competent authorities include any Minister, government department, public body, or person holding public office.

4 Protected features and status Sound of Arisaig SAC has been selected to become part of Scotland’s MPA network which in turn has been established to help conserve and recover a range of Scotland’s important marine habitats, wildlife, geology and landforms.

Table 1 provides a summary of the protected feature within the MPA, its condition within the site, and the broader conservation status of subtidal sandbanks.

The location and extent of the subtidal sandbanks within Sound of Arisaig SAC is shown on Figure 2 and is available to view at National Marine Plan Interactive.

Table 1. Condition status of subtidal sandbanks at Sound of Arisaig SAC. Feature condition refers to the condition of subtidal sandbanks assessed at a site level. Broader conservation status is the overall condition of the feature throughout its range.

Protected Feature Feature Assessment Broader conservation status* condition date Subtidal sandbanks Favourable 2014 UK: Unfavourable –Inadequate maintained European region: Unfavourable – bad

* This is the conservation status of the protected feature within the UK as reported in the Habitats Directive, Article 17 Report 2019 - https://jncc.gov.uk/our-work/article-17-habitats- directive-report-2019 and the Marine Atlantic Biogeographic Region in Europe as reported in Article 17 Report 2013.

Figure 2. Location of Sound of Arisaig SAC and distribution of subtidal sandbanks.

5 Setting Conservation Objectives

5.1 Background Under Regulation 33(2) of the Conservation (Natural Habitats, &c.) Regulations 1994 (as amended in Scotland) (hereafter referred to as the Habitats Regulations). Scottish Natural Heritage (now referred to as NatureScot) have responsibility for providing the Conservation Objectives for the SAC. These site-level Conservation Objectives seek to define the contribution that each site should make to the attainment of Favourable Conservation Status1 for the qualifying features. They provide the framework for the setting of site conservation measures (management) and for the Habitats Regulations Appraisal of projects and plans.

The Conservation Objectives for Sound of Arisaig SAC are provided in Annex 1.

5.2 Relationship between feature condition and Conservation Objectives The Conservation Objectives seek to maintain protected SAC feature(s) where evidence exists that it is in favourable condition in the site, or where there is uncertainty concerning the assessed condition of a feature (see section 4) but no reason to suspect deterioration in condition since designation. Where evidence exists that a feature is declining and/or damaged and therefore not in a favourable condition in the site, the Conservation Objectives will seek to restore the protected feature.

The subtidal sandbanks habitat is in favourable condition at Sound of Arisaig SAC and therefore the Conservation Objectives seek to maintain this condition.

5.3 Overlapping Marine Protected Areas boundaries The following MPA boundaries overlap with Sound of Arisaig SAC:

 Inner Hebrides and the Minches SAC  Loch Moidart and Loch Shiel Woods SAC  Kentra Bay and Moss SSSI  Loch Moidart SSSI

Conservation measures in the overlapping marine areas need to ensure the Conservation Objectives of Sound of Arisaig SAC, Inner Hebrides and Minches SAC and Loch Moidart and Loch Shiel Woods SAC are met.

There are no apparent management conflicts between the other protected features of the three MPAs.

6 Feature sensitivity The following sections provide an overview of the pressures most relevant to subtidal sandbanks. Further information on feature sensitivity, can be found at Marine Scotland’s Feature Activity Sensitivity Tool (FEAST)2 and also for the features not covered by FEAST, Marine Evidence based Sensitivity Assessment (MarESA)3. The information in FEAST reflects our current understanding of the interactions between activities, pressures and features. It highlights that activities can give rise to a range of pressures, which the protected

2 http://www.marine.scotland.gov.uk/feast/ 3 https://www.marlin.ac.uk/sensitivity/sensitivity_rationale 10

features may be sensitive to. Our assessment of sensitivity is based on a feature’s tolerance (response to change) and its ability to recover.

6.1 Subtidal sandbanks Subtidal sandbanks can be sensitive to physical disturbance. These habitats can also have a low resilience to the introduction or spread of invasive non-native species and can be sensitive to changes in water quality.

The sub-feature, maerl beds, are highly sensitive to physical disturbance2. The three- dimensional structure, quality and associated communities of maerl beds can be substantially affected by crushing, burial of live maerl and disruption of the surface and underlying sediment. Maerl beds are also highly sensitive to surface abrasion. In addition to direct impacts, maerl beds are sensitive to increased levels of sedimentation3. This causes smothering of the maerl and associated fauna and flora, blocking the water flow and exchange of oxygen, nutrients and also food for filter feeders associate with the beds. Maerl beds have a low/negligible rate of recovery due to their exceptionally slow growth rate.

The sub-feature, seagrass beds, are sensitive to changes in water flow, water quality and water clarity. They are also sensitive to physical disturbance which may uproot seagrass. Seagrass beds have a low resilience to these pressures and would not recover quickly.

7 Management

7.1 Conservation Measures The following conservation measures are currently in place for Sound of Arisaig SAC:

 The Habitats Regulations require all plans or projects that may cause an effect on the protected features of an SAC to be assessed against the Conservation Objectives for that site. This process is known as a Habitats Regulations Appraisal (HRA). An HRA is a rigorous statutory procedure that ensures the integrity of the site is maintained. It also provides an opportunity to consider appropriate mitigation that can reduce impacts, avoid adverse effects and permit plans or projects to proceed having taken full account of the protected features of an SAC.  Kentra Bay and Moss and Loch Moidart are also notified as Sites of Special Scientific Interest (SSSIs) and management changes described on the list of Operations Requiring Consent must have prior consent from NatureScot.  A management scheme was drafted for the Sound of Arisaig in the early 2000’s and this suggested voluntary fishery measures to safeguard the subtidal sandbanks. The scheme has been superseded by subsequent management measures.

7.2 Advice to support management Table 2 provides NatureScot’s advice on management for activities where we consider this may be necessary to achieve the Conservation Objectives for the protected features. The advice is focused on the activities that cause an effect (a pressure) that a feature is sensitive to. Pressures can be physical (e.g. abrasion of the seabed), chemical or biological. Different activities may cause the same pressure, e.g. fishing using bottom gears and aggregate dredging both cause abrasion which can damage the surface of the seabed.

Our advice takes a risk-based approach, i.e. we are focusing on providing advice where we believe there is a risk to achieving the Conservation Objectives. We have identified risks to achieving the Conservation Objectives where there is an overlap between protected features and activities associated with pressures that the features are sensitive to. We have provided management advice to support public authorities and others in managing these risks. Our

advice is based on existing data and information on protected features and relevant activities, and our understanding of the relationships between the features and activities. We have identified a range of management advice:

 management to remove or avoid pressures;  management to reduce or limit pressures; or  no additional management required.

For our advice on fisheries management we have also stated where we think this should be ‘considered.’ This term is included to highlight that an issue exists, but circumstances mean that a specific recommendation for action cannot / or need not be made at this point. However, there is sufficient cause to make fishery managers aware of the issue and for them to consider if a fishery management measure may be helpful in achieving Conservation Objectives – particularly where there may be a synergy between the benefits of management actions for the fishery and the Conservation Objectives for the feature. The term ‘recommended’ highlights than an issue of fishery-feature interaction exists, there is a reasonable evidence base and a specific recommendation can action can be made/ justified.

New or other activities not identified within the table would need to be considered on a case- by-case basis. We recognise that stakeholders can provide local environmental knowledge and more detailed information on activities, including in relation to intensity, frequency and methods. This additional information will help public authorities and others develop more specific management, focussed on the interaction between features and activities. If new information becomes available our management advice may be revised.

We recognise that stakeholders can provide local environmental knowledge and more detailed information on activities, including in relation to intensity, frequency and methods. This additional information will help public authorities and others develop more specific management, focussed on the interaction between features and activities. If new information becomes available our management advice may be revised. Where management measures are required, the development of these would be undertaken through discussion and consultation with the relevant stakeholders.

Table 2 describes the activities that are considered capable of affecting the protected features. Activities that are considered not likely to affect the protected features (other than insignificantly) are listed in Table 3. Spatial data relating to the location and extent of the activities listed can be accessed on Marine Scotland’s National Marine Plan Interactive4 (where available).

7.3 Best Practice In our management advice for activities in Table 2 we refer to the development, adoption or use of ‘best practice’ as a way of managing interactions between activities and the features. Best practice is taken to mean approaches or procedures that are developed and accepted by regulators and relevant stakeholders as being an effective way of dealing with an interaction between a habitat or species and the pressures created by an activity. Much of this best practice is already being implemented by sectors and regulators, e.g. pre- application discussions between developers and regulators, the Scottish Marine Wildlife Watching Code and Technical Standards for Scottish Finfish Aquaculture.

4 https://marinescotland.atkinsgeospatial.com/nmpi/ 12

Table 2. NatureScot’s advice to support management for Sound of Arisaig SAC for activities which are considered capable of affecting the protected features. The text under the ‘Advice to support management’ columns provides NatureScot’s management advice for the features in relation to the activities (further details about the terminology used are provided in section 7.2). Where a cell is coloured grey this indicates that management is already in place, this includes where there are existing regulatory requirements for new proposals. Cells are also coloured grey where it is considered there is no additional management required to achieve the Conservation Objectives. For some activities, the pressures associated with new proposals are considered unlikely to affect some the features either because these activities do not occur in the same locations as the features or the pressure is unlikely to be at levels that can affect the features (see also Table 3). In these cases, we have not provided advice however, where regulated; this does not exempt new plans or projects related to these activities undergoing a Habitats Regulations Appraisal (HRA).

Activities considered Advice to support management capable of affecting Subtidal sandbanks the protected features Aquaculture* Reduce or limit pressures associated with new farms and undeveloped consents as well as the expansion or relocation of existing farms.

Remove or avoid pressures associated with new farms and undeveloped consents as well as the expansion or relocation of existing farms where maerl beds or seagrass beds are present. Anchorages No additional management required for current anchorages.

Remove or avoid pressures associated with new anchorage areas where maerl beds or seagrass beds are present. Cables and pipelines* No additional management for existing cables and pipeline.

Remove or avoid pressures for new cables and pipelines which should focus on avoiding impacts to the maerl beds and seagrass beds. Coastal development Reduce or limit pressures - other Minimise the effects of coastal development which should focus on avoiding impacts to the maerl beds and seagrass beds. Discharges – Reduce or limit pressures associated with discharges from new activities or changes in existing activities. industrial and agricultural

Activities considered Advice to support management capable of affecting Subtidal sandbanks the protected features Remove or avoid pressures associated with discharges from new activities or changes in existing activities where maerl beds or seagrass beds are present. Dredging/extraction Remove or avoid pressures of material Fishing - demersal Remove or avoid pressures is recommended where maerl beds and seagrass beds are present. mobile/active gear* Reduce or limit pressures is recommended in all other areas.

Fishing – static gear* Reduce or limit pressures should be considered where maerl beds and seagrass beds are present.

No additional management required in all other areas.

Fishing – hydraulic Remove or avoid pressures is recommended where maerl beds and seagrass beds are present. (diver or vessel)* Reduce or limit pressures is recommended in all other areas.

Forestry Reduce or limit pressures associated with new tree plantations and felling activities that release sediment, fertiliser/insecticides and into the marine environment.

Remove or avoid pressures associated with new tree plantations and felling activities that release sediment, fertiliser/insecticides and into the marine environment where maerl beds and seagrass beds are present. Moorings* No additional management required for current moorings.

Remove or avoid pressures associated with new moorings where maerl beds and seagrass beds are present. Reduce or limit pressures with new moorings in all other areas. Ports and harbours* No additional management for existing ports and harbours.

Remove or avoid pressures associated with new ports and harbours or expansion or works on existing ports and harbours where maerl beds and seagrass beds are present. Reduce or limit pressures associated with new ports and harbours or expansion or works on existing ports in all other areas. Biosecurity planning should take place to prevent the introduction of INNS.

Table 3. Activities that are considered not likely to affect the protected features (other than insignificantly)5

Activity Comments Boat use associated with both Pressures unlikely to affect this feature. commercial and recreational activities (with the exception of Ferry routes – see separate advice) Ferry routes Pressures unlikely to affect this feature. Fishing – pelagic Pressures unlikely to affect this feature. Fishing –recreational Pressures unlikely to affect this feature. Fishing – diver collection of bivalves Diver collection of bivalves may take place but it is not considered to be at a level where it affects the protected feature of this site. Discharges – sewage Discharges are considered unlikely to reach a level where they will affect the protected feature of this site. Seaweed harvesting Pressures unlikely to affect this feature. Scientific survey/research Scientific research may take place but is not considered to be at a level where it will affect the features. Seismic survey Pressures unlikely to affect this feature. Tourism & recreation Pressures unlikely to affect this feature.

8 Research and survey requirements We recognise that there are still important gaps in our understanding and knowledge of the features of this site. We will identify research and survey projects to inform our understanding of these aspects. The requirements identified below are not a commitment to undertake this work. However, by highlighting these gaps we hope to inform future discussions with parties interested in undertaking research in this site and/or on these features, to help direct research and aid monitoring priorities.

1. Monitoring of the condition of the feature, in particular the maerl beds and seagrass beds within the site.

5 Only the specific examples of activities listed in the table have been excluded, rather than the broad activity types. New plans or projects will still need to be considered by the relevant competent authority (see Annex 1 for further details). 15

Annex 1. Sound of Arisaig SAC Conservation Objectives The box below provides the high-level Conservation Objective statements for Sound of Arisaig SAC. The full Conservation Objectives, which includes site-specific advice and information on the qualifying feature for the SAC are provided in the tables that follow.

These tables are grouped split by feature type, i.e. habitats or species. The site-specific advice and information provides more detail in relation to each of the high level Conservation Objective statements for each feature type, e.g. detail on the extent of a habitat within a site and what the supporting features are for a species.

Information is also provided below on how minor changes to features should be considered and the influence of environmental change on features, particular in relation to climate change. Temporary impacts on the qualifying features resulting from plans or projects can only be permitted where there is certainty that the features will be able to quickly recover. Further details on the potential for each qualifying feature to recover are described in more detail in Annex 2 ‘Factors determining the potential of features to recover’.

A definition of the terms used is in the Glossary (Annex 3).

A map of the SAC is provided in Figure 2.

The qualifying feature for Sound of Arisaig SAC is subtidal sandbanks. There are four sub- types of subtidal sandbanks all of which are present within Sound of Arisaig, gravelly and clean sands, muddy sands, maerl beds, and seagrass beds, the advice for the SAC is specific to these.

Sound of Arisaig SAC

Qualifying habitat(s): subtidal sandbanks

1. 1. To ensure that the subtidal sandbanks at Sound of Arisaig SAC are in favourable condition and make an appropriate contribution to achieving Favourable Conservation Status. 2. 2. To ensure that the integrity of Sound of Arisaig SAC is maintained in the context of environmental changes by meeting objectives 2a, 2b and 2c for subtidal sandbanks:

2a. Extent and distribution of the habitat within the site. 2b. Structure and function of the habitat and the supporting environment on which it relies. 2c. Distribution and viability of typical species of the habitat.

3. 1. To ensure that the subtidal sandbanks at Sound of Arisaig SAC are in favourable condition and make an appropriate contribution to achieving Favourable Conservation Status.

Favourable Conservation Status (FCS) is assessed across Europe within Biogeographic Regions. For subtidal sandbanks in this SAC, FCS is expected to be achieved across the Atlantic Biogeographic Region. In this Region, subtidal sandbanks are currently assessed as having an overall conservation status of ‘unfavourable – bad’ (2013).

When carrying out appraisals of plans and projects against these Conservation Objectives, it is not necessary to understand the status of qualifying features within each individual SAC in this Biogeographic Region. The focus of the appraisal should be to understand whether the integrity of Sound of Arisaig SAC (see Conservation Objective 2) would be maintained. If this is the case then its contribution to FCS across the Atlantic Biogeographic Region will continue to be met. Similarly, when determining whether management measures may be required to ensure that the Conservation Objectives for this site are achieved, the focus should be on maintaining the contribution that this site makes to FCS. Further advice on how these appraisals should be focussed in relation to maintaining site integrity is provided by Conservation Objective 2 (including parts a, b and c). If broader information (status, trends) on the qualifying features is available, it should be used to provide context to the site-based appraisal.

Note ‘Appropriate’ within this part of the Conservation Objectives is included to indicate that the contribution to FCS varies from site to site, and feature to feature.

2. To ensure that the integrity of Sound of Arisaig SAC is maintained in the context of environmental changes by meeting objectives 2a, 2b and 2c for subtidal sandbanks:

When carrying out appraisals of plans or projects, or determining whether management measures are required, the focus is maintaining site integrity, specifically by meeting the objectives outlined in 2a, 2b and 2c. If these are met then site integrity will continue to be maintained. Note that not all of these may be relevant for every activity being considered. Any impacts on the objectives shown in 2a, 2b or 2c must not persist so that they prevent the maintenance of site integrity. Temporary impacts on these objectives resulting from plans or projects can only be permitted where there is certainty that the features will be able to quickly recover.

Environmental changes These Conservation Objectives recognise that subtidal sandbanks are part of a complex, dynamic and multi-dimensional marine environment and that marine habitats are exposed to a wide range of drivers of change. ‘Environmental changes’ for the purpose of these Conservation Objectives means any change to subtidal sandbanks reflecting their natural cycle, and also broader environmental changes, i.e. those related to climate change and environmental variability that are beyond the scope of the site. The impact of human activities on the site that can be managed will not be considered as part of the broader context of environmental change, i.e. where required they should be managed.

Some of these changes are natural (e.g. population fluctuations/shifts or habitat changes resulting from natural processes) and are not a direct result of human influences. Changes in subtidal sandbanks extent, distribution, structure, function and typical species which are brought about by entirely natural drivers, directly or indirectly, are normally considered compatible with the site’s Conservation Objectives.

There may also be historical human influences that have now ceased but have modified and continue to drive change within the site. It is also recognised that climate change pressures could affect the qualifying feature within the site. These changes cannot be prevented, so the Conservation Objectives at a site level seek to take account of them and where possible, improve the habitats’ resilience to environmental change when considering future plans or projects. The magnitude of the future impacts will depend on the nature, scale, duration and intensity of the activity and the tolerance and ability of the qualifying feature to recover from such an impact.

Additionally, management of human activities at a wider scale (i.e. regional, Scotland or the area covered by an international agreement such as the OSPAR Convention), may also affect qualifying feature in this site (either by making a positive contribution or by having a negative impact). Wider scale impacts may affect the features ability of the features to recover from site level changes, and therefore additional precaution over the impacts of any future human activities may be necessary.

An assessment of whether a change is natural or human-induced, or a combination of both, will need to be looked at on a case-by-case basis.

In relation to Sound of Arisaig SAC, the following effects of environmental change (climate change) are relevant. These effects should be taken into account when considering plans and projects as additional pressures may reduce the habitat’s resilience to climate change, and conversely climate change impacts may start to hinder the their ability to recover from human activities.

 Subtidal sandbanks Gravelly and clean sands and muddy sands - Subtidal areas will not be as affected by changes in temperature as intertidal areas although fluctuations will occur in stratified waters or on the boundaries of frontal systems. Changes in salinity or temperature may occur on the sea bed if the stratification of the water column is broken down by storm events or by shifts in the position of fronts. Variations in temperature may have significant effects on diversity and may also affect the succession of macrobenthic species with the occurrence or survival of different groups of species related to periods of mild or cold winter temperatures (Elliot et al., 1998). An increase in sea level is likely to modify the influence of wave and tidal energy, as well as the availability of light for kelp. However, most species are likely to be able to colonise new substrata and tolerate these changing conditions. There are uncertainties with regard to the impact of increasing ocean acidity on species such as bivalves.

Maerl beds - Increased disturbance of any kind is a key pressure for maerl beds (Hinojosa-Arango et al., 2009) and so any increased levels of storminess is likely to have an impact. Individual thalli or nodules can be broken or moved by waves, currents or bioturbation (Steller and Foster, 1995; Harris et al., 1996; Marrack, 1999) and intense wave action can physically break maerl nodules and damage beds (Birkett et al., 1998b). It is suggested in FeAST (2013) that Phymatolithon calcareum is likely to have a medium tolerance to 18

increases in wave action. Similarly to Lithothamnion glaciale, nodules can be broken, and recovery is very slow. The increased suspended solids in the water column caused by the intensified wave action may also have deleterious effects on maerl beds, as L. glaciale is highly intolerant of smothering, and a low recoverability, therefore potential for resilience or adaptation against this is unlikely (FeAST, 2013). In addition, P. calcareum is also described as having a particularly low tolerance and high sensitivity to both smothering and increased suspended sediment (FeAST, 2013; MarLIN, 2016). Maerl has a high sensitivity to ocean acidification, although this may depend primarily on the rate of change, rather than the magnitude at which pCO2 enrichment occurs (Kamenos et al., 2013). A fast change in pH level may cause structural weakness, potentially having a deleterious effect on its ability to provide structurally sound habitats for the numerous species that depend on it.

Seagrass beds - the impacts of climate change on seagrass is likely to be mixed with different climate change related pressures having both positive and negative effects. In seagrasses, temperature strongly influences physiological processes, growth rates, reproductive patterns and geographical distribution. An increase in sea temperature may reduce winter die back and improve seed germination (Hootsmans et al. 1987), but in shallow waters it could result in a reduction of growth and periods of summer senescence (Kaldy 2014, Thom et al. 2014). Distributional changes, decreased photosynthesis and growth and mortality have been recorded in relation to temperature increase in the intertidal Zostera noltei (Valle et al., 2014).The effects of sea level rise on seagrass beds are likely to be location-specific and dependent upon the nature of the habitat and the presence of barriers (natural or anthropogenic) and the type and nature of human activities in the area. For example, a subtidal species such as Zostera marina may expand shorewards with sea level rise provided that suitable habitat was present (extensive mud and sandflats) (Short et al., 2016). In other areas there may be coastal squeeze and loss of supporting habitat. Due to their shallow or intertidal occurrence, seagrasses could be exposed to increased storminess, increased wave action/height and extreme weather events. Damage would be likely to result from erosion, including physical damage or removal of plants and roots, smothering, increased turbidity and exposure to increased concentrations of nutrients and pollutants, either through increased run-off or through disturbance of nutrients and contaminants sequestered within the sediments (Cabaço et al., 2008). There could be some benefits to seagrass beds from increased CO2 in the water promoting enhanced photosynthesis and growth (Zimmerman et al., 2017) but this could stress associated calcifying organisms which act as epiphytic grazers, which would be detrimental to seagrass.

2a. Extent and distribution of the habitat within the site

Temporary short-term and/or minor changes in the extent and distribution of subtidal sandbanks due to human activity may be considered not to compromise the Conservation Objectives within the site, provided recovery can be demonstrated with a high degree of certainty. The exception to this would be maerl beds and seagrass beds within the subtidal sandbanks, where further explanation is provided. Assessments should consider the timing, duration and scale of the impact on the qualifying features and their ability to recover. Factors limiting the recovery of qualifying features vary between features. Temporary change in the distribution of associated fauna and flora are covered under 2b and 2c.

Feature Site specific advice Site specific information Subtidal Maintain the extent Sound of Arisaig SAC comprises the outer sections of Loch Ailort, Loch Moidart and a large area sandbanks: and distribution of of Loch Ceann Traigh, along with the adjacent open fringe of coastal waters in West Lochaber. gravelly and subtidal sandbanks The shallow (<20m) inshore area of the site is dominated by sedimentary habitats (~72% including clean sands and within the site. maerl and seagrass beds). muddy sands Sandbanks form part of a dynamic system interacting with adjacent features. The extent and distribution of the subtidal sandbanks is determined by coastal processes and the influence of adjacent habitats and may therefore change over time. Subtidal Maintain the extent The Sound of Arisaig SAC supports some of the most extensive beds of maerl in the UK, these sandbanks: and distribution of rich and diverse maerl beds are present in Loch Ailort, Loch Moidart and Loch Ceann Traigh. maerl beds maerl beds within the Maerl biotopes were estimated to cover 171 ha of the inshore area (<20m depth) (GeMS, 2020). site. 2004).

Plains of maerl and coarse maerl gravel extending to depths beyond 20m occur in the open coast area of the site, although patchy in distribution here in sediment pockets between rock.

Loch Ailort is thought to have the largest area of dense live maerl in the site. In the outer part of Loch Ailort there was also an extensive maerl bed at depths of 1–5m along the main channel in to the middle reaches of the Loch. In weaker currents to either side of the channel the maerl gives way to finer sedimentary biotopes.

In the greater shelter of Loch Ceann Traigh, the maerl bed is much more extensive, being largely unbroken over an area of at least at depths of 5–8m, continuing eastward into the entrance channel to Kentra Bay and along the coast north of this (Moore et al., 2004). In the South Channel of Loch Moidart live maerl was only recorded for a distance of about 300m along the main channel.

The extent and distribution of maerl beds are likely to be limited by depth, water clarity and water movement. Maerl beds have a slow growth rate and therefore a slow rate of recovery. The key factors influencing the recovery of their extent and distribution are suitable habitat and environmental conditions as well as supply of live maerl fragments for propagation.

All disturbance to maerl beds by human activities is likely to be judged detrimental because it has the potential to cause a long-term or permanent reduction in the extent of the habitats and/or change the local distribution on a continuing basis. Additionally, maerl beds are rare in a national

and international context. Therefore any damage or disturbance that would lead to a reduction in extent and/or a restricted/modified distribution of the maerl beds should be avoided. Subtidal Maintain the extent 24ha of the inshore area supports beds of the eelgrass, Zostera marina (GeMS, 2020), the sandbanks: and distribution of principal area of distribution being shallow waters (<4m) in the outer part of Loch Ailort (Moore et seagrass beds seagrass beds within al., 2004). Zostera was found at the mouth of Glenuig Bay and at five stations spread out over a the site. distance of 2km between Goat Island and Roshven in the mouth of Loch Ailort, sometimes mixed with live maerl. Seagrass is also known from the northern coast of outer Loch Ailort (Howson 1990) and Loch Ceann Traigh (Howson and Donnan 2000).

Seagrass beds have a slow recolonization rate and therefore a slow rate of recovery. The key factors influencing the recovery of their extent and distribution are suitable habitat and environmental conditions. Recolonisation of Zostera is exclusively by rhizome growth from adjacent vegetated areas and therefore recovery potential is reduced as the degree of Zostera removal increases.

All disturbance to seagrass beds by human activities is likely to be judged detrimental because it has the potential to cause a long-term or permanent reduction in the extent of the habitats and/or change the local distribution on a continuing basis. Additionally, seagrass beds are rare in a national and international context. Therefore any damage or disturbance that would lead to a reduction in extent and/or a restricted/modified distribution of the seagrass beds should be avoided.

2b. Structure and function of the habitat and the supporting environment on which it relies.

Structure: Structure includes what the habitat is created from and what it requires to exist, e.g. habitat forming species, geological features or sediment; the depth of the substrate or thickness or height of the biogenic structures from the seabed; biogenic material forming the structure should still retain a live component where this exists at baseline.

Temporary changes in the structure of the qualifying features due to human activity may be considered, provided recovery of the associated biodiversity can be demonstrated with a high degree of certainty. The exception to this would be maerl beds and seagrass beds within the subtidal sandbanks, where further explanation is provided. Assessments should consider the timing, duration and scale of the impact on the subtidal sandbanks and their ability to recover.

Function: Functions include the environmental conditions and processes required for the habitat to exist and the key functions provided by the habitat to the site and wider supporting environment i.e. those where there is inter-dependence between the habitats and the supporting 21

environment. Sound of Arisaig SAC lies between the Ardnish and Ardnamurchan peninsulas on the west coast of Scotland and comprises the outer sections of Loch Ailort, Loch Moidart and a large area of Loch Ceann Traigh, along with the adjacent open fringe of coastal waters in West Lochaber. The geography in this area was shaped through the process of glaciation during the last ice age (10,000 years ago). Where the ancient glens reach below the present day sea level the ‘drowned’ coastline forms the Ailort, Moidart, and Ceann Traigh sea lochs within the Sound of Arisaig.

The site specific advice below identifies the environmental conditions required to maintain the habitat and the key functions each habitat provides to the supporting environment. Different habitats contribute to different functions to different degrees, all of which contribute to the supporting environment on which it in turn relies. Collectively the features contribute to a wider range of functions, while some such functions also operate more clearly at an ecosystem scale (e.g. at the scale of the bays and lochs of the site). An exhaustive list is not practical but the following are functions best considered at the scale of the whole site:  Resilience to invasive non-native species (INNS) and disease – the combined function of healthy and biodiverse habitats in Sound of Arisaig is likely to make significant contribution to the ability of the local ecosystem to resist, recover from or adapt to the introduction of a non-native or disease/pathogen.  Supply of recruits to other parts of the site.  Carbon storage and climate regulation – while substantial contributions from individual habitats are noted below with maerl beds providing a particularly large stock, Sound of Arisaig as a whole ranked 2nd (per unit area) in the total carbon stocks of Scotland’s Inshore MPAs (Burrows et al, 2017). The presence and maintenance of this stock is linked to other habitat functions and external factors.

Temporary changes in the environmental conditions due to human activity may be considered, provided recovery of subtidal sandbanks can be demonstrated with a high degree of certainty. The key functions provided by the subtidal sandbanks will continue into the future if the habitat is maintained in a favourable condition. The exception to this would be the maerl beds and seagrass beds within the subtidal sandbanks, where further explanation is provided. Assessments should consider the timing, duration and scale of the impact on subtidal sandbanks and its ability to recover. Feature Site specific advice Site specific information Subtidal sandbanks Maintain the overall water Sound of Arisaig was assessed as having a ‘High’ overall water body status in 2017 body condition status of (SEPA, 2019). This assessment includes consideration of water chemistry, pollutants, Sound of Arisaig the physical condition of the water body, plant and animal communities, including plankton, and the risk from invasive non-native species.

Maintain the The physical structure of the subtidal sandbanks is influenced by coastal processes and environmental conditions water movements therefore some change overtime may occur naturally. Maintaining the (processes) required to sandbanks relies on suitable environmental conditions. Environmental conditions, support healthy including water movement, water clarity and water quality, are important. The current status of these parameters provides suitable conditions for sustaining the subtidal 22

functioning subtidal sandbanks. If any one of the environmental conditions were to be significantly altered it sandbanks. could detrimentally affect the quality and variety and therefore functions of the subtidal sandbanks.

Maintain the physical The Sound of Arisaig has an unusually high diversity of sublittoral sediment habitats structure of subtidal within a relatively small area. All four Annex I subtidal sandbank sub-types are present sandbanks in the site. in the site; gravelly and clean sands, muddy sands, seagrass beds and maerl beds each supporting a representative range of communities and species.

Large areas of shallow sediment are found throughout the site, grading from soft, burrowed mud and muddy sands at the head of Loch Ailort to coarse, clean sand on the exposed coast. In the more exposed parts of the site in Loch Ceann Traigh and outside Loch Ailort, the sediments are coarser and cleaner, and grade into muddier more mixed sediments with increasing depth and shelter. The inner part of Loch Moidart is estuarine with some freshwater influence, particularly at the southern entrance. The South Channel contains tide swept shell gravel and stones, supporting communities indicative of brackish conditions. Further into Loch Moidart there are sublittoral estuarine sediments with characteristic communities. The recovery of subtidal sandbanks from impacts will be influenced by the type and duration of impact, and the level to which associated fauna have been impacted.

Maintain the functions The key functions provided by gravelly and clean sands and muddy sands at Sound of provided by subtidal Arisaig are: habitat for others, biomass production, carbon storage, climate regulation, sandbanks to the wider coastal protection, formation of physical barrier, nutrient cycling and breaking down ecosystem. waste and toxins.

Subtidal sandbanks usually have a low standing stock & sequestration of organic carbon, but a more significant standing stock of inorganic carbon that accumulates slowly. Sound of Arisaig as a whole ranked 2nd (per unit area) in the total carbon stocks of Scotland’s Inshore MPAs (Burrows et al, 2017).

The subtidal sandbanks have a role in biomass production and the diversity and abundance of life, along with tidal flushing allows the sandbank communities to be important in supporting connectivity. The physical structure of the sandbanks allows them to have a role in coastal protection, forming a physical barrier to waves and storm

surge. The infaunal communities make key contributions to nutrient cycling and breaking down waste and toxins helping to maintain clean water and sediments. Subtidal sandbanks: Maintain the three- Maerl nodules form loosely interlocking beds through which water is able to circulate, maerl beds dimensional structure of providing the perfect conditions for the development of diverse communities of plants the maerl beds, in and animals (on, within or under the beds). The presence of live maerl is important in particular the percentage maintaining the beds. The deeper exposed open coast maerl is distributed within the cover of live maerl. troughs of the low waves of coarse sand with shell and maerl gravel where it covers c.25-50%.In the areas as a whole the live maerl cover is about 10% of the seabed. In the more sheltered maerl beds of Loch Ceann Traigh live maerl is patch with an overall coverage of 20-30%. In Loch Ailort live maerl cover was around 50% but varied (Moore et al., 2004).

Maerl beds are believed to have poor ability to recover from impacts, and the key factors influencing the recovery of their structure include sufficient maerl fragments remaining for propagation. Maerl beds are rare in a national and international context. This combined with the limited ability of the feature to recover means that all disturbance to maerl beds by human activities is likely to be judged detrimental and should be avoided.

Maintain the functions The most important biological stores of inorganic carbon in Scotland are maerl beds. provided by maerl beds The calcium carbonate skeleton of maerl persists after the death of the living algal to the wider ecosystem. tissue and accumulates to form long-lasting deposits (Kamenos et al., 2004a, b). Maerl beds make key contributions to nutrient cycling and breaking down waste and toxins helping to maintain clean water and sediments. The maerl beds have a role in biomass production and provision of habitat through supporting epifaunal and infaunal communities including fish and shellfish species of commercial importance. Subtidal sandbanks: Maintain the three- Seagrasses typically grow in monospecific stands or beds which form a three- seagrass beds dimensional structure of dimensional structure allowing sediments to be trapped and stabilise and providing the seagrass beds, in habitat and shelter for other species. Beds of Zostera marina have been recorded in particular the percentage outer Loch Ailort, with Zostera density varying from abundant to superabundant (Moore, cover of seagrass sp. 2017). Seagrass beds have a slow recolonization rate and therefore a slow rate of recovery. The key factors influencing the recovery of their extent and distribution are suitable habitat and environmental conditions. Recolonisation of Zostera is exclusively by rhizome growth from adjacent vegetated areas and therefore recovery potential is reduced as the degree of Zostera removal increases. Seagrass beds are rare in a national and international context. This combined with the limited ability of the feature to 24

recover means that all disturbance to seagrass beds by human activities is likely to be judged detrimental and should be avoided.

Maintain the functions The seagrass beds have a role in biomass production and provision of habitat through provided by maerl beds supporting epifaunal and infaunal communities including fish and shellfish species of to the wider ecosystem. commercial importance. The seagrass beds in Sound of Arisaig also contribute to carbon storage and climate regulation due to their high sequestration rate of organic carbon. Seagrass beds and associated communities are known for their high nutrient cycling function. The seagrass beds make key contributions to nutrient cycling and breaking down waste and toxins helping to maintain clean water and sediments. Seagrass beds can also help to stabilise sediments affecting the suspension/settlement of sediment at a highly localised scale.

2c. Distribution and viability of typical species of the habitat.

It is expected that the viability of the typical species will continue to be maintained if Objective 2b is met and therefore the site specific advice and information does not provide any additional detail on this. It focuses on the distribution and diversity of typical species. The list of species provided below should be used as a guide to inform Habitats Regulations Appraisals of plans or projects with regard to this Conservation Objective. This summarises our knowledge as it currently stands but may be updated in the future as our knowledge improves.

Temporary changes in abundance and distribution of typical species, due to human activity may be considered, provided recovery of the typical species can be demonstrated with a high degree of confidence. The exception to this would be seagrass species, where further explanation is provided. Assessments should consider the timing, duration and scale of the impact on the qualifying features and their ability to recover. Site specific advice Site specific information Maintain the diversity, All four Annex I subtidal sandbank sub-types are present in the site; gravelly and clean sands, muddy sands, abundance and distribution of seagrass beds and maerl beds. Sandbanks support animals including bivalves, polychaete worms and typical species associated amphipods. These animals are prey for a variety of fish and bird species and include species of importance with subtidal sediments in to commercial fisheries e.g. scallops and razor shells. They also support kelp (Saccharina latissima) and this site (including seaweed communities on sublittoral sediment which is a Priority Marine Feature in Scotland. Saccharina latissimi, Amalosoma eddystonense, These habitats are possibly a significant feature for feeding harbour porpoise that regularly fish in this region Chaetopterus variopedatus as well as, otter. and Protanthea simplex).

In the muddy sands of inner Loch Ailort, a population of the rare, nationally scarce, echiuran worm Amalosoma eddystonense, is present. More widely distributed in the site, are mixed muddy sediments with the seapen Virgularia mirabilis and burrowing brittlestars Amphiura spp. The site supports species of both predominantly southern origin, such as the sipunculan worm Sipunculus nudus, and predominantly northern distributions, such as the starfish Luidia sarsi.

Dense clumps of the tubes of the large polychaete, Chaetopterus variopedatus, emerge from the soft sediments at the head of Loch Ailort and support dense populations of the anemone, Protanthea simplex. Although this lies just beyond the limits of the SAC, these worms display a similar phenomenon in the central region of the loch within the SAC, supporting a rich epibiota, particularly of ascidians (Moore et al., 2004). Maintain the diversity, A detailed study of five maerl sites in 2003 recorded a total of 236 animal species living within the maerl beds abundance and distribution of and 185 animal and algal species associated with the surface of the maerl beds (Moore et al., 2004). Maerl typical species associated biotopes are dominated by the maerl species, Phymatolithon calcareum with Lithothamnion glaciale also with maerl beds in this site recorded but only as nodular encrustations on stones (Moore et al., 2015). The invasive alga, Heterosiphonia (including Phymatolithon japonica, was recorded at all maerl beds on a survey in 2014, but at a low density (Moore et al., 2015). On calcareum, Lithothamnion maerl beds in Loch Ailort a rich cover of red and brown filamentous and foliose algae (c.60%) dominated by glaciale). Dictyota dichotoma, Membranoptera alata, Phycodrys rubens, Plocamium cartilagineum and the pink balled tufts of the sporophyte phase of Asparagopsis armata were recorded (Moore et al., 2004). Maintain the diversity, The most profuse and diverse fauna was found in an area of Zostera marina seagrass bed in 2003 (Moore et abundance and distribution of al., 2004). The more sheltered locations sampled were richer (abundance and species richness, 80 species) typical species associated than those having stronger water movement. with seagrass beds in this site (including Zostera marina).

Annex 2. Supporting information

Factors limiting the recovery of features Subtidal sandbanks (gravelly and clean sands and muddy sands) Subtidal sandbank habitats and their associated fauna are suggested to be sensitive to large scale physical change of the sea bed; a permanent change to another seabed habitat type is likely to lose the characterising community. Kelp and seaweed communities on sublittoral sediment are thought to be sensitive to physical disturbance though recovery is likely to be rapid for the majority of species, with large species such as kelp being the slowest to recover. Low energy sites with dense species cover will recover less quickly than high energy sites. Subtidal sandbanks are also predicted to be sensitive to organic enrichment, removal of target and non-target species, siltation changes, abrasion and variation in the current and wave energy regimes locally (FEAST, 2013).

Maerl beds Maerl beds have a very low potential to recover from disturbance. The most important factor in hampering the recovery of maerl is the extremely slow rate of growth. Maerl beds also depend on fragmentation for propagation, and there appears to be a lack of sexual reproduction in maerl species which further reduces their ability to recruit from elsewhere via dispersal. Recovery, if possible at all, is likely to be on the same time-scale as maerl bed turn-over and accumulation, i.e. hundreds of years. However, it should be noted that the communities associated with maerl occur on both live and dead maerl and if left undisturbed, may potentially recover regardless of the low recovery of maerl itself. This assumes that the integrity of the remaining maerl has been maintained (or can recover) to support an associated community. Further details are available in Mazik et al. (2015).

Seagrass beds Zostera species (and other seagrasses) are highly sensitive to physical disturbance in the form of abrasion (surface and sub-surface), physical removal, loss or change to the habitat. Additionally, seagrasses are highly sensitive to changes in water clarity, siltation rate changes and organic enrichment. It is of note that recovery potential following natural, physical disturbances is considered to be greater than that following anthropogenic disturbance and most human activities resulting in sediment deposition are thought to cause permanent changes to the sediment and permanent negative effects on seagrass (Cabaço et al., 2008). Seagrasses are highly susceptible to changes in nutrient status, turbidity and physical damage and documented recovery rates range from 2 years to over 7 years to reach a recovered state (Mazik and Smyth, 2013). Functional attributes, such as leaf and rhizome production and starch concentration can take more than 18 years to reach a recovered state, yet these attributes may be essential to long-term sustainability, and if the physical structure of the sediment is permanently changed, recovery may never be achieved.

Annex 3. Glossary for Conservation Objectives

Conservation Definition Objective term Distribution and This should outline the typical species that are associated with the diversity of habitat. The typical species include those that are especially relevant to typical species the habitat’s definition, e.g. species that form the structure of a bivalve of the habitat bed, or sea pens on burrowed mud. Viability of the typical species will be achieved if the structure and the function of the habitat is maintained/restored as appropriate. Therefore this Conservation Objective focuses on outlining their distribution within the site in relation to the habitat. Extent and The “extent” of a habitat is the total area that it covers. This should also distribution include consideration of the “distribution” i.e. how it is spread out within the site. A habitat could be continuous and contained within one area, dispersed in smaller patches over a wider area, or as a mosaic with other habitats. Indeed, it could also be a combination of these. Favourable This refers to the assessed condition of a feature through Site Condition condition Monitoring. Features considered to be in favourable condition for the purposes of these Conservation Objectives are those that have an assessed condition of either:  Favourable Maintained - the attribute targets set for the natural features have been met, and the natural feature is likely to be secure on the site under present conditions.  Favourable Recovered - the condition of the natural feature has recovered from a previous unfavourable condition, and attribute targets are now being met. . Favourable This is a measure of the condition of habitats and species listed in Annex Conservation I or II of the Habitats Directive. It applies at the relevant biogeographic Status region within the European Union. For the UK this is the Atlantic Biogeographic Region. It is achieved when a habitat or species throughout the zone is maintained in size and range and the conditions for its long-term existence are in place. Habitats and species within Scottish SACs contribute to achieving favourable conservation status within the Atlantic Biogeographic Region. Function This encompasses both the environmental processes on which the condition of each habitat depends and the key functions that each habitat provides to the wider site ecosystem. The text within the supplementary advice explains function in relation to both of these factors for the feature concerned where information is available. Maintain Where a qualifying feature of the SAC is assessed as being in favourable condition the Conservation Objective is ‘maintain’. This means that the various attributes of the feature should be kept at that favourable level. This can include increasing/improving condition as well, but not a permanent decline. Restore Where a qualifying feature of the SAC is assessed as being in unfavourable condition the Conservation Objective is ‘restore’. This means that the various attributes of the feature should be returned to the favourable level by increasing/improving condition.

Conservation Definition Objective term Site integrity The integrity of a site is defined in general terms as the coherence of its ecological structures and function, across its whole area, which enables it to sustain the habitat, complex of habitats and and/or the levels of populations of the species for which it was designated.

Supporting This includes the following environmental conditions (but is not limited environment to) which are important for maintaining/restoring the protected features, e.g. hydrography and supporting water currents, chemical water quality parameters, suspended sediment levels, radionuclide levels.

Structure The structure of a habitat includes what the habitat is created from and what it requires to exist, e.g. habitat forming species, geological features or sediment; the depth of the substrate or thickness or height of the biogenic structures from the seabed; biogenic material forming the structure should still retain a live component where this exists at baseline. Unfavourable This refers to the assessed condition of a feature through Site Condition condition Monitoring. Features considered to be in unfavourable condition for the purposes of these Conservation Objectives are those that have an assessed condition of either:  Favourable declining - The attribute targets set for the natural feature have been met, but evidence suggests that its condition will worsen unless remedial action is taken.  Unfavourable recovering - One or more of the attribute targets have not been met on the site, but management measures are in place to improve the condition.  Unfavourable no change - One or more of the attribute targets have not been met, and recovery is unlikely under the present management and activity on the site.  Unfavourable declining - One or more of the attribute targets have not been met, evidence suggests that condition will worsen unless remedial action is taken.

References

Birkett, D.A., Maggs, C.A. & Dring, M.J. (1998). Maerl (volume V). An Overview of Dynamic and Sensitivity Characteristics for Conservation Management of Marine SACs. Scottish Association of Marine Science.

Burrows, M.T., Hughes, D.J., Austin, W.E.N., Smeaton, C., Hicks, N., Howe, J.A., Allen, C., Taylor, P. & Vare, L.L. 2017. Assessment of Blue Carbon Resources in Scotland’s Inshore Marine Protected Area Network. Scottish Natural Heritage Commissioned Report No. 957.

Cabaço, S., Santos, R. & Duarte, C.M. 2008. The impact of sediment burial and erosion on seagrasses: a review. Estuarine Coastal and Shelf Science, 79, 354-366.

Elliott, M., Nedwell, Jones, S.V., Read,S.J., Cutts,N.D., Hemingway, K.L. 1998. Intertidal Sand and Mudflats & Subtidal Mobile Sandbanks (volume II). An overview of dynamic and sensitivity characteristics for conservation management of marine SACs. Scottish Association for Marine Science (UK Marine SACs Project). 151 Pages.

FeAST. 2013. FeAST - Feature Activity Sensitivity Tool. Online at http://www.marine.scotland.gov.uk/FeAST/

GeMS - Geodatabase of Marine features adjacent to Scotland. 2020. Available from: https://gateway.snh.gov.uk/natural-spaces/dataset.jsp?dsid=GEMS-PMF

Harris, P. T., Tsuji, Y., Marshall, J. F., Davies, P. J., Honda, N., Matsuda, H., 1996. Sand and rhodolith-gravel entrainment on the mid- to outer-shelf under a western boundary current: Fraser Island Continental Shelf, eastern Australia. Marine Geology, 129, 313-330.

Hinojosa-Arango, G., Maggs, C.A., Johnson, M.P. 2009. Like a rolling stone: the mobility of maerl (Corallinaceae) and the neutrality of the associated assemblages. Ecology, 90(2), 517- 28.

Howson, C.M. (1990). Surveys of Scottish sealochs: sealochs of Arisaig and Moidart. Nature Conservancy Council, CSD Report No. 1086.

Howson, C.M. & Donnan, D.W. (2000). Trials of monitoring techniques for biotopes in the Sound of Arisaig cSAC. Scottish Natural Heritage Commissioned Report F98PA09.

Kameno, N.A., Burdett, H.L., Aloisio, E., Findlay, H.S., Martin, S., Longbone, C., Dunn, J., Widdicombe, S., Calosi, P. 2013. Coralline algal structure is more sensitive to rate, rather than the magnitude, of ocean acidification. Global Change Biology DOI: 10.1111/gcb.12351

Kamenos, N.A., Moore, P.G. & Hall-Spencer, J.M. 2004a. Nursery-area function of maerl grounds for juvenile queen scallops Aequipecten opercularis and other invertebrates. Marine Ecology Progress Series 274: 183-189.

Kamenos, N.A., Moore, P.G. & Hall-Spencer, J.M. 2004b. Small-scale distribution of juvenile gadoids in shallow inshore waters; what role does maerl play? ICES Journal of Marine Science: Journal du Conseil 61: 422-429.

Marrack, E. C., 1999. The relationship between water motion and living rhodolith beds in the southwestern beds of California, Mexico. Palaios, 2, 189-191

Mazik, K., Strong, J., Little, S., Bhatia, N., Mander, L., Barnard, S. & Elliott, M. 2015. A review of the recovery potential and influencing factors of relevance to the management of habitats and species within Marine Protected Areas around Scotland. Scottish Natural Heritage Commissioned Report No. 771.

Mazik, M., Smyth, K. 2013. Is ‘minimising the footprint’ an effective intervention to maximise the recovery of intertidal sediments from disturbance? Phase 1: Literature review. Natural England Commissioned Reports, Number 110.

Moore, C.G. 2017. Biological analyses of underwater video from ongoing monitoring and research cruises in Lochs Sunart, Etive and Alsh, sea lochs off South Skye, the Sounds of Barra and Arisaig and around the Southern Trench. Scottish Natural Heritage Commissioned Report.

Moore, C.G., Lyndon, A.R. and Mair, J.M. (2004). The establishment of site condition monitoring of marine sedimentary habitats in the Sound of Arisaig cSAC. Scottish Natural Heritage Commissioned Report No. 071 (ROAME No. F02AA409).

Moore, C.G., Harries, D.B., Cook, R.L., Saunders, G.R., Atkinson, R.J.A. & Sanderson, W.G. 2015. 2014 site condition monitoring survey of marine sedimentary habitats in the Sound of Arisaig SAC. Scottish Natural Heritage Commissioned Report No. 807.

Short, F.T., Kosten, S., Morgan, P.A., Malone, S., Moore, G.E. 2016. Impacts of climate change on submerged and emergent wetland plants. Aquatic Botany. Available from: http://dx.doi.org/10.1016/j.aquabot.2016.06.006

Steller, D. L., Foster, M. S. 1995. Environmental factors influencing distribution and morphology of rhodoliths in Bahia Concepcion, B.C.S., Mexico. Journal of Experimental Marine Biology and Ecology, 194, 201-212.

Valle, M., Chust, G., Campo, A., Wisz, M.S., Olsen, S.M., Garmendia, J.M., Borja, A. 2014. Projecting future distribution of the seagrass Zostera noltii under global warming and sea level rise. Biological Conservation, 170, 74-85.