Offshore wind energy - draft sectoral marine plan: habitat regulations appraisal

10 In-Combination Effects

10.1 Introduction

10.1.1 The Habitats Regulations require that, in determining whether a plan or project is likely to have a significant effect on a European/Ramsar site, its effects should be considered both alone and in-combination with other plans or projects.

10.1.2 By definition, an in-combination effect within the Draft Plan would be between different DPOs and / or other plans or projects with connectivity to the same qualifying interests of a European/Ramsar site.

10.1.3 To inform this in-combination assessment, a review of existing plans and projects was initially carried out, allowing plans or projects with the potential to affect the same features as the Draft Plan to be identified.

10.2 Key Assumptions

10.2.1 In considering the potential for in-combination effects it has been assumed that windfarm development will occur within each of the 17 DPOs. Hence, the in-combination assessment encompasses those effects which could arise from development at any or all of the DPOs, in tandem with the potential effects that could occur as a result of other plans and projects.

10.2.2 As it is not possible to determine the degree of windfarm development that could occur within a DPO at this point in the Draft Plan process, indicative potential generating capacities have been used based on the overall scale of the draft Plan (as defined within the Offshore Wind Plan SEA). Although windfarm development within any of the DPOs would not fully encompass the extent of any DPO, for the HRA assessment it is assumed that development could potentially occur within any part of a given DPO.

10.3 Relevant Marine Projects and Plans

10.3.1 Initially a full review of extant and relevant plans and projects was carried out. Although a lot of the information on extant marine renewable projects is held by Marine Scotland and The Crown Estate, there is no complete central repository for such information across all the marine renewable sectors.

10.3.2 Proposed and operational offshore renewable energy developments in Scottish waters were first identified (Section 10.4; Table 21). Other plans and projects which could potentially affect the same features as the Draft Plan were also identified (Section 10.5). Careful consideration was then given to the outcomes of project-level HRAs and EIAs for Scottish windfarm proposals (Section 10.6), including the outcomes of Appropriate Assessments carried out by MS-LOT and MSS on behalf of Scottish Ministers.

10.3.3 Scotland currently has five operational offshore wind sites with a total capacity of 320 MW: the Beatrice demonstrator project (two 5 MW turbines, currently undergoing decommissioning), the Hywind Scotland Pilot Park project (30 MW capacity), Robin Rigg (180 MW capacity), Levenmouth Demonstration Turbine (one 7 MW turbine) and, during 2018, the European Offshore Wind Deployment Centre (EOWDC) deployed 11 turbines, with a total capacity of 93.2 MW.

10.3.4 While the number of operational windfarms is small within Scottish Territorial Waters, there are currently plans to install up to 1.9 GW capacity of offshore wind in three short-term option sites (Beatrice, Inch Cape and Neart na Gaoithe), together with up to 4.15 GW capacity within two Round 3 sites in offshore waters (Moray Firth (1.7 GW) and Firth of Forth (2.45 GW)). All five of these major offshore wind developments in Scottish waters were consented in 2014. However, applications for revisions to several of these projects (e.g. Inch Cape; Neart na Gaoithe; Moray East) have required new HRAs to support the applications. The Moray West Offshore Wind Farm (up to 85 turbines) was consented in June 2019 following four consultation exercises carried out by Scottish Ministers.

10.3.5 The Beatrice windfarm project is currently under construction and is expected to be fully operational by the end of 2019, with a total capacity of 588 MW.

10.3.6 Although a large number of wave and tidal developments are in development/in planning, particularly associated with the Pentland Firth and Orkney Waters lease areas and lease awards made in relation to the Saltire Prize (see Table 21), relatively few are operational.

10.3.7 The MeyGen tidal stream project is currently under construction in the Pentland Firth. Phase 1 installed four 1.5 MW tidal turbines, now operational, as a precursor to the development of the remaining consented 86 MW project and potential future expansion.

10.3.8 The European Marine Energy Centre (EMEC) provides a range of testing facilities for wave and tidal devices around Orkney.  Operational devices are currently being tested at the Billia Croo (wave energy), Scapa Flow (wave energy), Fall of Warness (tidal stream energy) and Shapinsay Sound (tidal stream energy) sites. The Islay LIMPET wave device was the world’s first commercial wave power device connected to the United Kingdom's National Grid. Following the construction of a 75-kW prototype in 1991, a 500-kW unit was built in 2000 (later downgraded to 250 kW) and was decommissioned in 2018. The 300 kW (3 x 100 kW turbines) North Yell tidal array was installed and commissioned in early 2014 in the Bluemull Sound in Shetland; the project is 100% owned by the local community, making this the world's first community-owned tidal energy project, and there are plans to double capacity of the site.

10.3.9 The key strategies or planning context for these marine renewable energy projects include:

• National Marine Plan;
• Blue Seas Green Energy – Sectoral Marine Plan for Offshore Wind Energy in Scottish Territorial Waters;
• Scottish Energy Strategy;
• Shetland Marine Plan;
• National Renewables Infrastructure Plan;
• Marine Renewables Infrastructure Plan;
• National Planning Framework 3;
• The pilot Pentland Firth and Orkney Waters Marine Spatial Plan (PFOW MSP);
• Scottish Sustainable Marine Environment Initiative (SSMEI);
• Electricity Ten Year Statement;
• Proposals for additional wave and tidal development lease areas including through the Further Scottish Leasing Rounds;
• Demonstrator wave and tidal energy projects;
• The Northern Ireland strategic wave, wind and tidal energy areas; and
• The R3OWF Plan (e.g. Moray Firth, Firth of Forth).

10.4 HRA Review

10.4.1 As mentioned above, to help inform this in-combination assessment, particular consideration was given to the findings from various EIA reports and HRAs carried out for windfarm projects in Scottish Territorial Waters (see Table 21).All potential impact pathways from windfarm proposals have been previously identified through review of plan and project level HRAs (see Table 2), including those projects listed below (Table 22). In addition, mitigation measures derived from a range of previous strategic assessments and plan-level HRAs for the Marine Renewable Sector have been tabulated (Table J1, Appendix J) against each of the key impact pathways.

10.4.2 These details can be used to inform high-level in-combination effects reviews but, over the longer-term they can also provide a basis for informing the future Iterative Plan Review (IPR) process (see Section 11.4). It is also hoped that this information will provide a useful guide to developers and regulators to identify some of the key impacts of future projects and the mitigation/monitoring requirements that might be relevant.

Table 22: Operational and planned offshore wind, tidal and wave renewable energy projects within Scottish Territorial Waters

Energy Type	Name/ Location	Company (Project Website)	Status	Capacity (MW)
Wind	Robin Rigg	E.ON https://www.eonenergy.com/About-eon/our-company/generation/our-current-portfolio/wind/offshore/robin-rigg	Fully operational since September 2010.	174
Wind	Beatrice Demonstrator	SSE Renewables / Talisman	Entering decommissioning (2024 – 2027)	10
Wind	Levenmouth Turbine	ORE Catapult https://ore.catapult.org.uk/press-releases/levenmouth-turbine-offers-unrivalled-opportunity-for-renewable-energy-rd/	Fully operational	7
Wind	Hywind	Equinor / Masdar http://www.statoil.com/en/environmentsociety/environment/impactassessments/newenergy/intwind/pages/hywindscotland.aspx	Fully operational	30
Wind	Aberdeen Bay (EOWDC)	Vattenfall http://www.statoil.com/en/environmentsociety/environment/impactassessments/newenergy/intwind/pages/hywindscotland.aspx	Fully operational	93.2
Wind	Beatrice	SSE Renewables / SDIC / Copenhagen Infrastructure Partners http://sse.com/whatwedo/ourprojectsandassets/renewables/Beatrice	Fully operational	588
Wind	Neart na Gaoithe	EDF Renewables http://www.neartnagaoithe.com	Consented December 2018 (Varied June 2019).	450
Wind	Firth of Forth 1 (Seagreen Alpha and Bravo)	SSE Renewables http://www.seagreenwindenergy.com	Consent granted October 2014 (varied August 2018 to remove maximum capacity). Updated application for optimised project submitted September 2018. Construction anticipated to commence by 2022.	1500
Wind	Moray East	EDPR http://www.morayoffshorerenewables.com/Home.aspx	Consent granted in March 2014. Delivery expected early 2020s.	950
Wind	Inch Cape	SDIC http://www.inchcapewind.com	New application submitted August 2018.	700
Wind	Kincardine	Atkins / Pilot Offshore Renewables http://pilot-renewables.com/	Consent received 2017. Currently under construction (one turbine operational)	49.6
Wind	Dounreay Tri Demonstration Project	Hexicon https://www.hexicon.eu/dounreay-tri/	Currently on hold, delivery expected 2020 (company in administration)	12
Wind	Firth of Forth 2 (Charlie)	SSE Renewables http://www.seagreenwindenergy.com	In planning	1800
Wind	Firth of Forth 3 (Delta)	SSE Renewables http://www.seagreenwindenergy.com	In planning	800
Wind	Moray Firth Western Development Area	EDPR http://www.morayoffshorerenewables.com/Home.aspx	Consented June 2019. Delivery potential in mid 2020s	850
Wind	Forthwind OWF, Methil	Forthwind Ltd	Consented, (Consent varied May 2019 to increase capacity)	29.9
Wind Total				8209.7
Tidal Stream	North Yell, Bluemull Sound, Shetland	Nova Innovation (https://www.novainnovatio n.com/bluemull-sound)	Fully operational since 2017. Expansion to 0.6 MW planned.	0.3
Tidal Stream	Sound of Islay	Scottish Power Renewables (http://www.scottishpowerrenewables.com/pages/sound_of_islay.asp)	Consent granted in March 2011. Pre-construction. (not currently active as a project)	10
Tidal Stream	Ness of Duncansby, Pentland Firth	Scottish Power Renewables (http://www.scottishpowerrenewables.com/pages/ness_of_duncansby.asp)	In early stages of planning. Agreement to lease secured.	95
Tidal Stream	Westray South, Pentland Firth	DP Energy (http://www.dpenergy.com/projects/tidal/westray-south)	In development. Agreement to lease secured. Scoping Report submitted November 2011.	200
Tidal Stream	Brough Ness, Pentland Firth	Simec Atlantis Energy (https://simecatlantis.com/projects/)	In development.	100
Tidal Stream	Inner Sound, Pentland Firth	Simec Atlantis Energy (https://simecatlantis.com/projects/meygen/)	Phase 1 (6 MW) in operation.	398
Tidal Stream	Mull of Kintyre, Argyll	Argyll Tidal Ltd (http://www.gov.scot/Topics/marine/Licensing/marine/scoping/ArgyllTidalArray)	Consent granted in May 2014 for one demonstration turbine (0.5MW) to be installed. Pre-construction.	0.5
Tidal Stream	Isle of Islay, Islay	DP Marine Energy Ltd (http://www.dpenergy.com/projects)	In development. Agreement to lease secured. Consent received 2017.	30
Tidal Stream	Lashy Sound	Scotrenewables Tidal Power Limited (SRTP) (https://www2.gov.scot/Top ics/marine/Licensing/marin e/scoping/LashySound)	In development. Agreement to lease secured. Scoping Report submitted in July 2014.	10
Tidal Stream	Brims Tidal Array (formerly Cantick Head)	SSE Renewables and OpenHydro Group Ltd (http://sse.com/whatwedo/ourprojectsandassets/renewables/brims)	In development. Agreement to lease secured. EIA submitted 2016 (company in administration)	200
Tidal Stream	Mull of Galloway	Marine Current Turbines (https://simecatlantis.com/projects/galloway/)	In planning. Agreement to lease secured.	30
Tidal Stream	Fall of Warness	European Marine Energy Centre Ltd	Test site. Operational Feb 2019.	N/A
Tidal Stream	Shapinsay Sound	European Marine Energy Centre Ltd	Test site.	N/A
Tidal Stream	Islay Demonstration Zone	European Marine Energy Centre Ltd	Test site.	N/A
Tidal Stream	Stronsay Firth	European Marine Energy Centre Ltd	Test site.	N/A
Tidal Total				1,073
Wave	Billia Croo	European Marine Energy Centre Ltd	Test site	N/A
Wave	Scapa Flow	European Marine Energy Centre Ltd		N/A
Wave	Scottish Sea Farms (MANTA) - Teisti Geo	Scottish Sea Farms	Marine Licence Granted May 2018 (Operational)	0.262
Wave	WaveNet Mingary	Wavenet Energy Mingary Ltd.	Marine Licence issued – operational	0.45
Wave	Harris Demonstration Zone	European Marine Energy Centre Ltd	Test site	N/A
Wave Total				0.712
Hybrid	Katanes Floating Energy Park	Katanes Floating Energy Ltd	Screening opinion issued November 2017	11.6
Hybrid Total				11.6

10.5 Other Plans and Projects

10.5.1 In addition to the offshore marine renewable projects, a wide range of other plans and projects are potentially relevant including:

• Marine Renewables Infrastructure Plan (MRIP);
• National Renewables Infrastructure Plan (N-RIP) (e.g. Port of Dundee, Port of Leith);
• The National Planning Framework for Scotland (NPF3);
• The Crown Estate Scotland (ScotWind) Leasing Round;
• The Crown Estate Offshore Wind Leasing – Round 4
• Waterfront regeneration projects (e.g. Helensburgh);
• Harbour expansion projects (e.g. Aberdeen);
• Onshore wind farms;
• Increased vessel activity from all sources (no specific plan), including offshore development and shipping from other ports;
• ISLES project;
• ISLES II project;
• Proposals for the offshore grid and other proposed cable routes;
• Container transhipment hub at Scapa Flow;
• Other proposals included within the pilot Pentland Firth and Orkney Waters Marine Spatial Plan;
• Oil and gas development activities;
• Port and marina developments (e.g. Granton);
• Aquaculture developments;
• Fishing activities;
• Military activities;
• Terrestrial developments potentially affecting Atlantic salmon, freshwater pearl mussel or otter features associated with SAC rivers.

10.5.2 An overarching National Marine Plan was introduced in Scotland through the Marine (Scotland) Act 2010.  The plan, adopted in March 2015, is designed to inform decision making in the marine environment by governing more detailed planning at the regional level and informing marine licensing and other decision-making functions.  An HRA was carried out for this Plan and following the screening stage of that process it was concluded that an AA was not required.  Having followed SNH guidance, this view was taken in respect of both the Plan’s ‘cross-cutting’ and ‘sector-specific’ policies as follows:

• The cross-cutting policies are general in direction, as they apply to all activities and development in the marine environment.  In consequence, no connectivity or direct pathway for impact was identified between these and specific European sites.
• The sector-specific policies are general in direction, as they do not direct development or activities to a particular location and do not have a pathway for impact on specific European sites.  For those which could have a significant effect on the integrity of European sites, mitigation measures have been recommended in the form of changes to the wording of the policies.

10.5.3 In conclusion, the National Marine Plan was considered to have no significant effect on the integrity of European sites, and for the same reason there will be no in-combination effects between the Sectoral Offshore Wind Plan and the National Marine Plan.  The Sectoral Offshore Wind Plan provides the spatial strategy for developing offshore wind energy at the national and regional level.  This spatial strategy has been assessed within this plan-level HRA.  Future developments which take place within these areas will be assessed against the proposals and policies contained within the National Marine Plan at the project licensing stage.

10.5.4 It should also be noted that in the coming years regional Marine Plans will be developed (e.g. Clyde Regional Marine Plan). These regional plans will include more focused policies for the coastal regions and, as such, an HRA for these plans may be required.

10.6 Assessment Review

10.6.1 The review of operational and planned marine windfarm projects indicated a high degree of similarity between the impact pathways described.  All of the 18 generic impact pathways that have been identified and assessed for the Sectoral Offshore Wind Plan HRA (see Table 2) were considered to some degree within project-level HRAs for the proposed or operational windfarm projects.

10.6.2 Within the windfarm project assessments, the key impact pathways which were consistently considered included:

• Direct and indirect damage to habitats;
• Physical damage and mortality to species, especially birds, due to collision risk;
• Non-physical disturbance to species due to displacement effects, noise and vibration effects and effects from Electromagnetic Fields (EMF); and
• Non-toxic contamination due to elevated turbidity.

10.6.3 It is evident that the main concerns at a project-level for offshore windfarm developments relate to: the direct and indirect damage to habitats within and adjacent to the footprint of the development and the potential impacts to mobile species via collision risks (especially birds), disturbance (visual, noise and vibration) and displacement.

10.6.4 The direct and indirect effects to benthic habitats and species in the vicinity of individual developments is well understood.  These relatively localised impacts from future projects are foreseeable and can be addressed/offset through mitigation and or compensation, as required, if they result in an adverse effect on a European/Ramsar site.  Although the DPOs do not directly overlap with any European/Ramsar site, there is potential for direct effects to occur as a result of cable routeing and landfall.

10.6.5 Spatial planning and array design at a project level will be key in contributing towards mitigation of such impacts. However, there also remains an opportunity to reduce the likelihood of adverse effects on designated habitats through spatial planning at a plan-level (see Section 11).

10.6.6 Hence, the greatest risk of an in-combination impact from windfarms is likely to be for mobile interest features, with the potential to adversely affect these receptors through a variety of activities and pathways, during different phases of the development. A high-level review of the potential in-combination effects on mobile features from the Draft Plan with other windfarm developments has been carried out below.

10.6.7 For non-renewable marine projects the range of impact pathways will differ, however, the in-combination effects on mobile features such as marine mammals, fish and birds remain key considerations. Coastal developments such as waterfront enhancements and port expansions could result in prolonged periods of underwater noise (with potential effects on seals and cetaceans) (e.g. the construction phase of Aberdeen Harbour Expansion Project).  Terrestrial activities for developments might affect river SACs and could result in in-combination effects for Atlantic salmon, freshwater pearl mussel and otter interest features.  Within the offshore environment there are a number of potential developments over a range of sectors (fishing, oil and gas etc.) for which there could be in-combination effects to, for instance, habitats or foraging species.

10.6.8 Although non-renewable and other renewable (tidal stream and wave energy) developments have the potential for in-combination effects with the Draft Plan, the key risks to mobile features will arise from in-combination effects with other offshore windfarm developments. These risks have been explored in the following sections to understand the likelihood of an AEOI, with consideration of appropriate plan-level mitigation (Section 11) to minimise these risks.

10.6.9 It is recognised that seismic surveys associated with oil and gas surveys are generally of greater magnitude than those associated with development under this plan, and therefore there is potential for in-combination effects.

10.7 Mobile Features

10.7.1 The key risks to marine mammals and fish are generally considered to occur during the construction phase (see Table 14, Table 15 and Table 17), thus there is greater opportunity for the application of project-level mitigation (see Table J1 and J2, Appendix J) to minimise the effects of certain activities. Conversely, the key risks to seabirds from windfarm developments will generally occur during the operational phase (Table 9) with more limited options for suitable mitigation outwith design and spatial planning.

10.7.2 Offshore windfarm development (proposed and operational) is comparatively greater along the east and northeast coast of Scotland (i.e. Forth, Tay and Moray regions). Therefore, the conclusions of HRA in-combination assessments of windfarm proposals from these regions provide a useful indication of the likely effects on mobile qualifying features. Consultation advice, issued in 2018, from SNCBs in relation to commercial windfarm proposals in Scottish waters was reviewed. It is assumed that where an AEOI has been concluded by a SNCB in relation to a mobile feature then there is an increased risk of AEOI in-combination with the Draft Plan. Where available, the conclusions of Appropriate Assessments (e.g. Moray Firth East (2014); Beatrice (2014); Neart na Gaoithe (2018)) carried out by MS-LOT and MSS, have been acknowledged.

10.7.3 Conversely, offshore windfarm development along the southwest, west and north coast of Scotland is minimal; with Robin Rigg in the Solway Firth. The results of a 5-year post-construction monitoring study carried out at Robin Rigg windfarm provide empirical evidence on the utilisation of the area by birds, mammals and fish. These results have been used to inform this assessment review where appropriate.

10.7.4 Birds, marine mammals and migratory fish have been reviewed in turn with reference to regional areas if relevant to further plan-level consideration of the potential for in-combination effects.

Birds

10.7.5 In 2018, project-level HRA consultation advice received from SNCBs in relation to commercial windfarm proposals, along the east and north-east coast of Scotland highlighted the adverse in-combination effects on seabird populations. An AEOI, from in-combination effects on seabirds, by way of collision and/or displacement effects occurring during the operational phase, was identified for several large-scale offshore windfarm proposals in the Forth, Tay and Moray regions (see Table 21).

10.7.6 Since submission of the application for Neart na Gaoithe (revised) windfarm, an Appropriate Assessment carried out by Marine Scotland (01/12/18) concluded that the development would not lead to an AEOI either alone or in-combination with other plans or projects. Neart na Gaoithe was consented in December 2018. Similarly, an Appropriate Assessment carried out by Marine Scotland (26/04/19) concluded that the Moray West wind farm development would not lead to an AEOI either alone or in-combination with other plans or projects.

10.7.7 Given the consistency of HRA consultation responses in relation to in-combination effects on seabirds from offshore windfarms in the Forth, Tay and Moray, the general scientific consensus, based on current available evidence and modelling, suggests that there is little available carrying capacity in these regions for further windfarm development. Hence, at this time, where there is likely to be connectivity to seabird colonies already thought to be affected by ongoing offshore windfarm development, then further windfarm development within the DPO(s) has a greater risk of an AEOI.

Table 23: SNCB advice during 2018 on project level HRAs for large scale commercial wind farm proposals in Forth, Tay and Moray. 

Region	Site name	Turbines	Planning phase	SNH consultation response (in summary)
Moray	Moray West	up to 85	Consented June 2019	Object to proposal (07/09/18; 04/01/19; 12/04/19) In-combination with Moray East and Beatrice will have AEOI for: Kittiwake as a qualifying interest of the East and North Caithness Cliffs SPAs (collision risk) Great Black-backed Gull as a qualifying interest of the East Caithness Cliffs SPAs (collision risk)
Forth	Seagreen (Alpha and Bravo phase 1) (revised)	120	Application submitted September 2018	Object to proposal (02/11/18) In-combination with Inch Cape and Neart na Gaoithe likely AEOI for Black-legged Kittiwake and Northern Gannet as qualifying interests of Forth Islands SPA (collision risk) Black-legged Kittiwake as qualifying interests of the Fowlsheugh SPA (collision risk)
Tay	Inch Cape (revised)	72	Application submitted August 2018	Object to proposal (28/09/18) In-combination with Neart na Gaoithe and Seagreen will have AEOI for Black-legged Kittiwake, Northern Gannet (collision risk) and Razorbill (displacement) as qualifying interests of Forth Islands SPA Black-legged Kittiwake (collision) and Razorbill (displacement) as qualifying interests of the Fowlsheugh SPA
Tay	Neart na Gaoithe (revised)	54	Consented December 2018	Object to proposal (07/09/18 and 08/10/18) In-combination with Inch Cape and Seagreen will have AEOI for Black-legged Kittiwake, Northern Gannet (collision risk) and Razorbill (displacement) as qualifying interests of Forth Islands SPA Black-legged Kittiwake (collision) and Razorbill (displacement) as qualifying interests of the Fowlsheugh SPA Black-legged Kittiwake (collision) as qualifying interests of the St Abbs Head to Fast Castle SPA

10.7.8 European designated sites highlighted in recent consultations (see Table 21) as adversely affected by proposed and ongoing windfarm developments in Scottish Territorial Waters include:

• Forth Islands SPA
• Fowlsheugh SPA
• St Abbs Head to Fast Castle SPA
• East Caithness Cliff SPA
• North Caithness Cliff SPA

10.7.9 It is acknowledged that the HRA advice for recent commercial windfarm proposals (see Table 23) is based on current ‘worst case scenarios’ e.g. the Neart na Gaoithe application (April 2018) considered in-combination effects with the earlier 2014 consented schemes at Inch Cape and Seagreen, and vice-versa. In the case of Neart na Gaoithe (revised) and Moray West, when the appropriate assessments were carried out by Scottish Ministers (December 2018 and April 2019 respectively), acknowledgment was given to the highly precautionary assumptions within the assessments; this contributing to the decision that these proposals would not lead to an AEOI.

10.7.10 Despite the emerging scientific evidence such as species-specific flight speeds recorded at Thanet by Skov et al. ^[333] and the collision avoidance rates recorded in the same study, the assessment of in-combination effects of any additional offshore windfarms in the Forth, Tay and Moray is likely to require more evidence to conclude no AEOI. Accordingly, further high-level consideration is given to the potential in-combination effects of the Sectoral Offshore Wind Plan in the Forth, Tay and Moray regions (Section 10.8 and 10.9).

10.7.11 Concerns have previously been raised in relation to collision risk of windfarms to migrating birds, seabirds and non-seabirds, in particular on the potential effects of multiple windfarms on the migratory passage of Whooper Swan^[334];^[335],^[336]. A key migration flyway for Whooper Swan encompasses the Cumbrian coast, Solway Firth and the North Channel, along the west coast of Scotland. Fifty percent of whooper swans are estimated to fly at collision risk height ^[337] hence, the in-combination effects of windfarm development along the southwest and west coast of Scotland, when considered with proposed and operational windfarms such as at Robin Rigg, Ormonde, Walney, Barrow and Burbo Bank, may increase collision risk and lead to an AEOI where, for example, Whooper Swan are a qualifying feature of a European/Ramsar site.

10.7.12 A focussed study in 2014 looking at the potential impact of operational windfarms on migratory birds concluded that at a strategic level all non-seabirds and almost all seabirds did not appear to be at risk of significant levels of additional mortality due to collisions alone with Scottish offshore windfarms^[338]. At Robin Rigg, bird surveys carried out monthly or bimonthly from 2001 to 2011, encompassing baseline, construction and post-construction phases recorded six Whooper Swan in total, two of which were flying^[339].

10.7.13 It is realised that future development from TCE Round 4 leasing may lead to additional windfarm development within the key migration flyway for Whooper Swan (see above) and as further detail of the Round 4 leasing emerges then the potential for in-combination effects should be revisited. The proposed plan-level mitigation provides a mechanism for continuous review and updates to the Draft Plan (Section 11.4).

Marine mammals

10.7.14 SNCB consultation responses to project level HRAs at Inch Cape (revised), Moray West, Seagreen (revised), Neart na Gaoithe (revised) and Dounreay Tri Floating project have consistently concluded that compliance with consent conditions would be sufficient to result in no adverse effect on marine mammals as qualifying features of designated sites, either alone or in-combination with other developments. Similarly, the Appropriate Assessments for Beatrice, Moray Offshore East, Neart na Gaoithe (revised) and Dounreay Tri Floating project concluded the same.

10.7.15 Anecdotal evidence from post-consent monitoring at Robin Rigg windfarm suggests that both harbour porpoise and grey seal were present within the survey area within 24 hours of piling events, as has been previously reported at other windfarm sites.

10.7.16 Although it is considered that the adoption of project-level mitigation measures at an individual DPO would avoid an in-combination AEOI, there is scope for an additive cumulative effect from construction (e.g. underwater noise from piling activities) if development at DPOs coincided within a particular area. There is potential for temporal sequencing of DPO development within a particular area to avoid additive effects. However, such an approach could extend the duration of effects. It is considered that such risks are most appropriately and effectively managed at project level.

10.7.17 Furthermore, should development at sites further offshore occur simultaneously with oil and gas survey activities, there is potential for additive in-combination effects on marine mammals to occur. The level of activity in the future from oil and gas survey is uncertain, and therefore it is considered that such risks are most appropriately and effectively managed at project level.

Fish

10.7.18 SNCB consultation responses to project level HRAs at Inch Cape (revised), Moray West, Seagreen (revised), Neart na Gaoithe (revised) and Dounreay Tri Floating project have consistently concluded that compliance with consent conditions would be sufficient to result in no adverse effect on diadromous (migratory) fish and freshwater pearl mussel as qualifying features of designated sites, either alone or in-combination with other developments. Similarly, the Appropriate Assessments for Beatrice, Moray Offshore East, Neart na Gaoithe (revised) and Dounreay Tri Floating project concluded the same.

10.7.19 The post-consent monitoring study at Robin Rigg suggested that the construction and operation of the Robin Rigg Offshore Wind Farm has not had any significant or permanent impact upon the fish and benthic fauna in the immediate or surrounding area of the windfarm^[340].

10.7.20 Although it is considered that the adoption of project-level mitigation measures at an individual DPO would avoid an in-combination AEOI; there is scope for an additive cumulative effect from construction (e.g. underwater noise from piling activities) if development at DPOs coincided within a particular area. There is the potential that a commitment to temporal sequencing of DPO development within a particular area would avoid additive effects. However, such an approach could extend the duration of effects. It is considered that such risks are most appropriately and effectively managed at project level.

10.8 Forth and Tay In-combination

10.8.1 SNH has advised that an AEOI for Kittiwake, Northern Gannet and Razorbill from the in-combination effects of proposed offshore windfarms in the Forth and Tay is likely for several designated sites (see Table 23)

10.8.2 Scottish Kittiwake populations have experienced significant declines over the last 30 years, as has been highlighted in advice received from both SNH and RSPB consultation responses (e.g. Neart na Gaoithe Offshore Windfarm consultation responses). The RSPB Kittiwake utilisation distribution map indicates relatively high utilisation of the waters overlapping DPO E3 (Figure 7). This DPO is within 30 km from both the Buchan Ness to Collieston Coast SPA and Fowlsheugh SPA; and approximately 100 km from the Forth Islands SPA.  Given that the mean maximum foraging range of Kittiwake is 60 km ^[341], it is assumed that Kittiwakes from the colonies at Buchan Ness to Collieston Coast SPA and Fowlsheugh SPA would potentially be affected by development at E3, with an increased likelihood of an AEOI, particularly at Fowlsheugh SPA, when considered in-combination with the consented Neart na Gaoithe and the proposals at Inch Cape and Seagreen.

10.8.3 DPOs E1 and E2 are further offshore than E3, approximately 60 km at their nearest point to the Kittiwake colonies at Fowlsheugh SPA and Buchan Ness to Collieston Coast SPA respectively. Kittiwake utilisation within these DPOs is considerably lower than that at E3 (Figure 7).

10.8.4 There is potential for development in E3 to have an effect on Razorbill populations from the Fowlsheugh SPA as a large proportion of E3 is within the foraging range distance from the SPA and RSPB utilisation data (Figure 8) suggests some usage of the western half of E3 by Razorbill. However, the smaller mean maximum foraging range (48 km^[342]) of Razorbill compared to Kittiwake reduces the overlap with other Forth and Tay windfarms and therefore subsequently reduces the potential for significant in-combination effects. Both E1 and E2 are beyond the mean maximum foraging range for Razorbill from the Fowlsheugh SPA colony, while E1, E2 and E3 are all beyond the mean maximum foraging ranges for Razorbill from the Forth Islands SPA.

10.8.5 Gannets forage much further than Kittiwake (mean maximum foraging range of 229 km) and therefore individuals from Forth Islands SPA could be affected by development in DPOs E1, E2 and E3.

10.8.6 A recent study by Garthe et al.^[343] found that gannets largely avoided the windfarm area to the north of Helgoland, implying that Northern Gannets may be more at risk from displacement than collision. Similarly, a five-year post construction monitoring study at Robin Rigg windfarm did not record any flying gannets, possibly indicating macro-avoidance behaviour of the site.

10.8.7 Although the general assumption is that nearer shore windfarm developments are worse for seabirds than those further offshore, this assumption has not yet been tested. However, observations from ship surveys^[344] and tagging data^[345] seem to indicate that fewer Northern Gannet may utilise the waters around and within DPOs E1 and E2, the most offshore sites, than areas which coincide with proposed windfarm developments (i.e. Seagreen, Inch Cape and Neart na Gaoithe) and DPO E3. For example, results from a Northern Gannet tagging study of the Bass Rock colony showed a greater density of foraging flights nearshore than directly offshore^[346].

10.8.8 The Forth Islands SPA, for which Northern Gannets are a qualifying feature, is over 100 km from E1, at its nearest point, and approximately 170 km from E2. Although E3 is approximately the same distance from the Forth Islands SPA as E1, it is much closer inshore than E1 and E2. At a plan-level, acknowledging current scientific evidence, consultation advice issued in 2018 for windfarm proposals in the Forth and Tay and the general consensus that the carrying capacity for several bird interest features of SPAs is close to being reached, the potential in-combination effects from development in E3 with Neart na Gaoithe, Seagreen and Inch Cape will likely lead to an AEOI. The in-combination effects would be compounded by additional development in E1 and E2, if it were to occur.

10.8.9 Development at the more offshore sites, E1 and E2, is less likely to result in an AEOI from in-combination effects, as at their closest points they are at the limits of Kittiwake mean maximum foraging ranges from the nearest SPA colonies.

10.8.10 Recent consultation regarding the effects on gannets in the Forth and Tay regions has highlighted collision risk as the key in-combination impact from proposed windfarms (see Table 23). The large foraging range of Gannets means that individuals from the Forth Islands SPA could be affected by development at DPOs E1 and E2, although considering the distances offshore and from the Bass Rock colony, the risk of an AEOI from in-combination effects with either E1 or E2 would be comparatively less than at E3.

10.8.11 SEANSE (Strategic Environmental Assessment North Sea Energy) is an EU funded project which will produce a regional strategic assessment of the impacts on seabirds from offshore wind development scenarios in the Forth and Tay region. The study will use currently available tools and information to establish an up-to-date baseline of seabird behaviour and habitat use in the Forth and Tay region, and then develop and undertake a strategic ornithology assessment for the region based on different development scenarios. One of the tools that will be used in the newly developed seabird sensitivity mapping tool, which provides spatial information on the sensitivity of seabird populations based on windfarm footprint size and location. Both the seabird sensitivity mapping tool and outputs from the SEANSE project will help support the evidence base for future HRAs. As mentioned previously, the proposed plan-level mitigation provides a mechanism for continuous review and updates to the Draft Plan allowing for new evidence to be acknowledged as it becomes available (Section 11.3).

Figure 7: RSPB utilisation distribution data for Black-legged Kittiwake

Figure 8: RSPB utilisation distribution data for Kittiwake, Shag, Guillemot and Razorbill

10.9 Moray In-combination

10.9.1 SNH has advised that in-combination effects from the proposed Moray West windfarm with the consented Moray East and Beatrice offshore windfarms will likely lead to an AEOI for Kittiwake as a qualifying feature of East and North Caithness Cliffs SPAs (Table 23). From the RSPB Kittiwake distribution map, relatively high utilisation of the waters overlapping DPOs NE2-NE6 is indicated (Figure 7). NE 2-5 are all located within 60 km of the Kittiwake colonies at the East and North Caithness Cliffs SPAs and are thus within the mean maximum foraging range for this species.

10.9.2 At a plan-level, acknowledging current scientific evidence, consultation advice received for Moray West in 2018 and 2019 (see Table 23) and the general consensus that the carrying capacity for Kittiwake interest features of East and North Caithness Cliffs SPAs is close to being reached, the potential in-combination effects from development at any of the DPOs with connectivity (NE2-5) with the consented Moray East, Moray West and Beatrice offshore windfarms will likely lead to an AEOI. In addition, although less is known about foraging behaviour from Great Black Backed Gulls, there is potential for sites in the NE region to have an effect on the North Caithness Cliffs SPA population, particularly given that large gull species are known to be of higher collision risk^[347].

10.9.3 Development at the more offshore Moray sites, NE7 and NE8, would be beyond the Kittiwake mean maximum foraging ranges from the nearest SPA colonies, and are thus less likely to result in an AEOI from in-combination effects. Seabird distribution maps provided by RSPB (see Figure 8) have indicated minimal utilisation in the waters around and within NE7 and NE8 for Kittiwake, Razorbill, Guillemot and Shag.

10.9.4 The DPO NE6 is beyond 60 km from the East and North Caithness Cliffs SPAs and hence the mean maximum foraging distance for Kittiwake; however, it is within 60 km of the Troup, Pennan and Lion’s Heads SPA which has Kittiwake as a qualifying feature, as are DPOs NE4 and NE5. Consultation issued by SNH for Moray West and Moray East did not conclude that there would be an AEOI for Kittiwake (or any other feature) as a qualifying feature of the Troup, Pennan and Lion’s Heads SPA. However, it is considered that if windfarm development were to occur at all these DPOs (NE4-6) it would potentially lead to an in-combination AEOI on Kittiwake at Troup, Pennan and Lion’s Head SPA. The level of cross connectivity between Kittiwake colonies in the Moray region is unknown; however, there is likely to be some connectivity between the East and North Caithness Cliffs SPAs.

10.9.5 As the DPOs NE2 to NE5 are all within 60 km of at least two SPAs which have Kittiwake as a qualifying feature, there is considerable risk of AEOI on these SPAs when considered in-combination with the consented Beatrice, Moray East and Moray West windfarms.