6.             Offshore Biological Environment

6.1.        Benthic Subtidal and Intertidal Ecology

6.1.1.    Introduction

335. This section of the Offshore EIA Scoping Report identifies the elements of the benthic subtidal and intertidal ecology receptors of relevance to the Proposed Development and considers the potential impacts from the construction, operation and maintenance, and decommissioning of the offshore and intertidal components (seaward of the MHWS mark) of the Proposed Development on benthic subtidal and intertidal ecology.
336. Benthic subtidal and intertidal ecology was included in the initial Offshore EIA Scoping Report. Although the change in project scope applied to this Offshore EIA Scoping Report, which is combining the offshore Proposed Development Array Areas, the impacts are anticipated to generally be the same as identified in the initial Scoping Report. The initial Berwick Bank Wind Farm Proposal Scoping Opinion response has been considered for the development of this section.

6.1.2.    Study Area

337. To support the development of the benthic subtidal and intertidal ecology EIA section, two study areas are defined:

• Proposed Development benthic subtidal and intertidal ecology study area: this is defined as the area encompassing the Proposed Development (see Figure 6.1  Open ▸ ). This is the area within which site-specific benthic surveys will be undertaken, the results of which will inform the baseline characterisation and identification of benthic receptors against which potential impacts associated with the Proposed Development will be assessed; and
• regional benthic subtidal and intertidal ecology study area: this is defined as the area encompassing the wider northern North Sea habitats and includes the neighbouring consented offshore wind farms and designated sites (see Figure 6.1  Open ▸ ). It will be characterised by desktop data and will provide a wider context to the site-specific data collected within the Proposed Development benthic subtidal and intertidal ecology study area.

 

Figure 6.1:  Benthic Subtidal and Intertidal Ecology Study Areas

6.1.3.    Baseline Environment

338. This section provides a concise summary of the benthic ecology baseline environment of the Proposed Development, reference should be made to Appendix 7  Open where a detailed description is provided. In 2020, a subtidal survey was undertaken to provide up to date data for baseline characterisation. The survey combined DDV and 0.1 m2 Hamon grab sampling with epibenthic trawls. The survey design was discussed and agreed with NatureScot and Marine Scotland in July 2020. This site-specific data along with the comprehensive desktop information and data sources available will aid the characterisation of the benthic subtidal and intertidal ecology baseline.

Subtidal Sediments

339. Based on the EUSeaMap data, regions of higher topography and those associated with the Banks complexes within the Proposed Development Array Area are dominated by deep circalittoral coarse sediments whereas those in deeper water and in the flanks of the banks are dominated by deep circalittoral sands (Figure 6.2  Open ▸ ). These two broad habitat types are also predicted across most of the proposed ECC, with discrete areas of faunal communities on deep low energy circalittoral rock. As the proposed ECC moves into shallower waters and approaches landfall, sandy sediments grade into deep circalittoral muds, deep circalittoral mixed sediments and deep circalittoral coarse sediments.
340. Side scan sonar (SSS) data collected during the site-specific geophysical surveys (Fugro, 2020a and Fugro 2020b) was correlated to the European University Information Systems (EUNIS) Classification data available from EMODnet. The data indicates a heterogenous sediment across the Proposed Development Array Area with coarse and cobbly sediments on topographic highs, and sand to gravelly sand in the topographic lows and on the flanks of the banks. There are also extensive boulder fields present across the broad topographic highs and the banks. Hard substrates are present in the nearshore area of the proposed ECC for the Thortonloch landfall, with sand sediments in the central section grading into more gravelly sands and areas of hard substrate.

Sediment Contamination

341. As part of the subtidal survey, sediment samples were taken for the purpose of sediment chemistry analysis. Samples were transferred to an appropriate sample container, labelled and sent to a suitable qualified laboratory for analysis. The RPS laboratory has United Kingdom Accreditation Service (UKAS) accreditation to carry out the tests for all the contaminants listed. Samples were analysed for the following contaminants:

• Metals;
• Polychlorinated biphenyl (PCB) congeners;
• Total Hydrogen Content (THC) by fluorescence spectrometry;
• Total organic Carbon (TOC);
• Organotins;
• Polycyclic aromatic hydrocarbons (PAH);Physical parameters; and
• Particle size analysis.
  342. No contaminants were found to exceed AL1/AL2 or the Canadian Probable Effect Levels (PEL) with only arsenic at five sample stations within the north of the Proposed Development Array Area exceeding Canadian Threshold Effect Level (TEL).

Subtidal Benthic Communities

343. The site-specific surveys across the Proposed Development benthic subtidal and intertidal ecology study area reported the benthic subtidal biotopes (as shown in Figure 6.3  Open ▸ ). The west of the Proposed Development Array Area was dominated by mixed sediment, fine sand and sandy mud biotopes (SS.SMu.CSaMu.AfilMysAnit in the south, SS.SSa.CFiSa.EpusOborApri in the north and SS.SMx.OMx.PoVen and SS.SSa.CFiSa.ApriBatPo). The east of the Proposed Development Array Area was dominated by sandy mud and find sand biotopes (SS.SMu.CSaMu.AfilMysAnit and SS.SSa.CFiSa.EpusOborApri). The Proposed Development ECC was dominated by the seapen and burrowing megafauna OSPAR habitat SS.SMu.CFiMu.SpnMeg with areas of SS.SMx.OMx and CR.MCR.EcCr in the nearshore environment.
344. The S.spinulosa Annex I reef assessment assigned all sample stations analysed ‘Not a Reef’. The nearshore area of the Proposed Development ECC recorded medium and low potential Annex I cobble reef. The Proposed Development Array Area recorded areas classified as ‘Not a Reef’ and two sample stations which were low potential reef. One sample station in the nearshore area of the Proposed Development ECC was classified as medium potential rock reef.
345. The marine ecology surveys conducted for Seagreen Alpha/Bravo found that the benthic habitats were characterised by patchy communities of polychaete worms and shellfish (Seagreen, 2012a). The distribution of the epifauna from these surveys was related to the sediment type with the sandy gravels and gravelly sands supporting a rich epifauna, while the slightly gravelly sands were generally low in epifauna. The majority of species recorded were opportunistic species, with bryozoans / hydroid turfs, tube worm Hydroides norvegica, pea urchin Echinocyamus pusillus and sea squirt Ascidiella scabra. High species richness was recorded in association with areas of the Sabellaria habitat, although no evidence from the DDV surveys suggests extensive or well-developed aggregations of Sabellaria in the Seagreen Alpha/Bravo Proposed Development Array Area. The benthic communities present were considered typical of the outer Firth of Forth and northwest North Sea (Seagreen, 2012a).
346. An overview of the benthic communities observed within Seagreen Alpha/Bravo benthic surveys is presented in Table 6.1  Open ▸ .

 

Table 6.1: Benthic Ecology Community Overview from Seagreen Project Alpha and Seagreen Project Bravo Survey Data (Seagreen, 2012a)

 

Intertidal Ecology

347. The proposed landfall locations are located at Thortonloch and Skateraw near to Torness, on the East Lothian coast. The following sections presents a summary of the site-specific survey data collected during intertidal surveys of each landfall. The methodology for intertidal surveys was approved by both MS-LOT and NS.

Thortonloch Landfall

348. The Thorntonloch Landfall rock platform is predominantly covered by sediments. A sandy bay is present at Thorntonloch beach which was mainly composed of fine and medium grained sand which becomes muddier at the lower shore. A small proportion of gravel was also present within the lower shore sands. Occasional strips of shingle (cobbles and pebbles) were present at the beach head. High cliffs occurred to the south of Thorntonloch beach abutting a sedimentary rock platform with overlying large mobile sediments (pebbles, cobbles and boulders). Large areas of the bedrock remained exposed and contained a mosaic of deep pools cut into the rock platform by wave action. Rockpools also occurred frequently in other rocky areas between and under seaweeds and stones.
349. Cobbles dominated the mixed sediments in the upper fucoid zone with a typical percentage coverage of cobbles of around 75%. Boulders were distributed throughout the rocky vertical shore profile and generally ranged from 10-75% cover in fucoid dominated habitats where bedrock was not extensively outcropping. Boulders accounted for approximately 80% or more of the upper substrate layer in lower shore kelp beds, except where kelp was directly attached to bedrock. Pebbles and cobbles were also abundant throughout the rocky areas of the site and occasionally formed patches of shingle at the beach head. Coarse sand was occasionally present at the head of the beach in small patches in and around shingle.

Skateraw Landfall

350. The Skateraw Landfall rock platform is predominantly covered by sediments. A sandy bay is present at Skateraw beach which was mainly composed of fine and medium grained sand which becomes muddier at the lower shore. A small proportion of gravel was also present within the lower shore sands. Larger mobile sediments (pebbles, cobbles and boulders) covered the rest of the rock platform with exposed areas of bedrock occurring in places. Rockpools frequently occurred in the rocky zone. Boulders were distributed throughout the rocky vertical shore profile and generally ranged from 10-75% cover in fucoid dominated habitats where bedrock was not extensively outcropping. Boulders accounted for approximately 75% or more of the upper substrate layer in lower shore kelp beds, except where kelp was directly attached to bedrock. Cobbles dominated mixed sediments in the upper fucoid zone with typical percentage coverage of around 75%.
351. Pebbles and cobbles were present throughout the rocky areas of the landfall, and were abundant where they formed an extensive shingle bank at the beach head in the northern section of the landfall. Coarser sand was occasionally present at the head of the beach in small patches at the foot of the shingle bank. Freshwater flowed into the intertidal zone from the Dry Burn at National Grid Reference (NGR) NT 73461 75928.

Figure 6.2:  Predicted EUNIS Habitats from the EUSeaMap for the Proposed Development Array Area and Proposed ECC (Source: EMODnet, 2014)

Figure 6.3: Combined Infaunal and Epifaunal Biotope Map of the Proposed Development Benthic Subtidal and Intertidal Ecology Study Area

Designated Sites

352. A number of sites of nature conservation importance, which are designated for benthic subtidal and/or intertidal features, have been identified as overlapping with, or occurring in close proximity to, the Proposed Development (Table 6.2  Open ▸ ). Further information is presented in Appendix 7  Open .

 

Table 6.2: Summary of Designated Sites with Relevant Benthic Ecology Features in Proximity to the Proposed Development

 

353. Information to support a full screening of European sites[4] with qualifying benthic subtidal and/or intertidal interest features will be provided in the LSE Screening Report. Relevant features screened in will be fully considered and assessed in the benthic subtidal and/or intertidal ecology Offshore EIAR section, with the information to support the assessment on European sites and features provided in the Report to Inform Appropriate Assessment (RIAA).

6.1.4.    Potential Proposed Development Impacts

354. A range of potential impacts on benthic subtidal and intertidal ecology have been identified which may occur during the construction, operation and maintenance, and decommissioning phases of the Proposed Development in the absence of designed in measures:

• Construction

–           Temporary habitat loss / disturbance;

–           Increase in suspended sediments due to construction related activities such as possible seabed preparation activities if required, wind turbine foundation installation, cable installation and the potential impact to physical features within the Proposed Development Array Area;

–           Accidental pollution during construction; and

–           Impacts from release of sediment bound contaminants.

• Operation and Maintenance

–           Long-term subtidal habitat loss;

–           Temporary subtidal habitat loss / disturbance;

–           Colonisation of hard structures;

–           Accidental pollution during operation and maintenance;

–           Impact to benthic invertebrates due to electromagnetic fields (EMF); and

–           Changes in physical processes.

• Decommissioning

–           Temporary habitat loss / disturbance;

–           Removal of hard substrates;

–           Accidental pollution during the decommissioning phase;

–           Impacts from release of sediment bound contaminants; and

–           Increased suspended sediment concentrations and associated deposition.

6.1.5.    Designed in Measures

355. The following designed in measures, and how these can reduce potential for impact have been considered in identification of impacts that have been scoped into (Table 6.3  Open ▸ ) or out of (Table 6.4  Open ▸ ) the Proposed Development assessment:

• the development of, and adherence to, an appropriate CoCP;
• the development of, and adherence to, an Environmental Management Plan, including Marine Pollution Contingency Plan and Invasive Non-Native Species (INNS) Management Plan; and
• development of, and adherence to, a Decommissioning Plan.
  356. The requirement and feasibility of additional measures will be dependent on the significance of the effects on benthic subtidal and intertidal ecology and will be consulted upon with statutory consultees throughout the offshore EIA process.

6.1.6.    Potential Impacts after the Implementation of Designed in measures

357. Potential impacts on benthic subtidal and intertidal ecology receptors have been identified, following consideration of Designed In Measures. The impacts that have been scoped into the Proposed Development assessment are outlined in Table 6.3  Open ▸ together with a description of supporting site-specific survey data and other analyses (e.g. modelling) that will be required to enable a full assessment of the impacts. On the basis of the baseline benthic subtidal and intertidal ecology information currently available and the Proposed Development description outlined in section 2  Open ▸ , several impacts are proposed to be scoped out, as described in Table 6.4  Open ▸ .

 

Table 6.3: Impacts Proposed to be Scoped In to the Proposed Development Assessment for Benthic Ecology. Project Phase Refers to Construction (C), Operation and Maintenance (O) and Decommissioning (D) Phase of the Proposed Development

 

 

Table 6.4: Impacts Proposed to be Scoped Out of the Proposed Development Assessment for Benthic Ecology

 

6.1.7.    Proposed Approach to the Environmental Impact Assessment

358. The benthic subtidal and intertidal ecology EIA will follow the methodology set out in section 4  Open ▸ . Specific to the benthic subtidal and intertidal ecology EIA, the following guidance documents will also be considered:

• Guidelines for EcIA in the UK and Ireland. Terrestrial, Freshwater and Coastal (CIEEM, 2019);
• Guidance on Environmental Considerations for Offshore Wind Farm Development (OSPAR, 2008);
• Best methods for identifying and evaluating Sabellaria spinulosa and cobble reef (Limpenny et al., 2010);
• Defining and Managing Sabellaria spinulosa Reefs (Gubbay, 2007);
• Identification of the Main Characteristics of Stony Reef Habitats under the Habitats Directive (Irving, 2009);
• SNH (now NatureScot) guidance: Guidance on Survey and Monitoring in Relation to Marine Renewables Deployments in Scotland – Volume 5: Benthic Habitats (SNH, 2011); and
• Guidelines for data acquisition to support marine environmental assessments of offshore renewable energy projects (Judd, 2012).
  359. In addition, and specific to marine ecology topics, important ecological features (IEFs) will be identified, in accordance with CIEEM (2019) guidelines, and assessments will be presented for appropriate ecological receptor groups in the baseline characterisation of each relevant technical section. Criteria defining the value of each IEF will be defined to reflect topic-specific interests, with reference to the CIEEM (2019) guidelines and will include specific consideration of Priority Marine Features (PMFs)[5] within the benthic subtidal and intertidal ecology study area. With specific reference to benthic subtidal and intertidal ecology, in particular the characterisation of the baseline environment, the Feature Activity Sensitivity Tool (FeAST), will be drawn upon to inform the assessments of sensitivity in the impact assessment section of the Benthic Ecology ES section.
  360. Additionally, a staged Marine Protected Area (MPA) assessment will be undertaken to assess the potential for the activities associated with the construction, operation and maintenance and decommissioning of the Proposed Development to hinder site conservation objectives. This MPA assessment will consider Marine Protected Areas within or near the Proposed Development based on the outputs of a Stage 1 Screening Exercise, including the Firth of Forth Banks Complex ncMPA.
  361. A Benthic Subtidal and Intertidal Ecology Technical Report will present a detailed baseline characterisation for the Proposed Development using specific survey data and the most recent desktop data. This report will inform the Benthic Ecology ES section.

Potential Cumulative Effects

362. Although the predicted effects from the Proposed Development on benthic subtidal and intertidal ecology are considered to be localised to within the footprint of the Proposed Development, there is potential for the predicted impacts to interact with impacts from other projects and activities in the regional benthic subtidal and intertidal ecology study area and lead to a cumulative effect on receptors. The cumulative effects assessment will follow the approach outlined in section 4.3.7.

Potential Transboundary Impacts

363. A screening of transboundary impacts has been carried out and is presented in Appendix 3  Open . No potential transboundary effects have been identified for benthic subtidal and intertidal ecology and therefore this will not be considered within the EIAR.

6.1.8.    Scoping Questions to Consultees

• Do you agree with the study areas defined for benthic subtidal and intertidal ecology?
• Do you agree that all potential impacts (Table 6.3  Open ▸ ) have been identified for benthic subtidal and intertidal ecology?
• Do you agree with the sites screened into the MPA Assessment (as presented in Appendix 17  Open )?
• Do you agree that the impacts described in Table 6.4  Open ▸ can be scoped out of the benthic subtidal and intertidal ecology EIA section?

6.1.9.    Next Steps

364. The following topic specific next steps are summarised below and will be undertaken through the Benthic Ecology, Fish and Shellfish and Physical Processes Road Map process:

• define the baseline environment and assessment approach and seek agreement on this with key stakeholders:

–           present evidence base (including site-specific subtidal and intertidal surveys), baseline characterisation (including key habitats and coastal processes) to stakeholders and agree on impacts and receptors to be scoped in/out of Offshore EIAR; and

• Agree assessment approach for benthic ecology and the potential impacts to be assessed through the EIA Report process:

–           present Maximum Design Scenarios and impact assessment approach including sensitivity of receptors, method of quantifying impacts to stakeholders; and

–           discuss initial findings of impact assessment, appropriate mitigation and monitoring with stakeholders.

365. Any impacts that cannot be quantitatively assessed will be discussed with key stakeholders as part of the Benthic Ecology, Fish and Shellfish and Physical Processes Road Map process.
366. Any potential need for strategic monitoring regarding hard structure colonisation and change in community structure / species will be detailed in the Benthic Subtidal and Intertidal Ecology section of the Offshore EIAR.

 

 

6.2.        Fish and Shellfish Ecology

6.2.1.    Introduction

367. This section of the Offshore EIA Scoping Report identifies the fish and shellfish receptors of relevance to the Proposed Development and considers the potential impacts from the construction, operation and maintenance, and decommissioning of the offshore and intertidal components (seaward of the MHWS) of the Proposed Development.
368. Fish and shellfish ecology was reported on in the initial Scoping Report. Although the change in project scope applied to this Scoping Report, which is combining the offshore Proposed Development Array Areas, the impacts are anticipated to generally be the same as identified in the initial Scoping Report. The SOR requested additional impacts were scoped in, such as the colonisation of hard substrates and the assessment of diadromous fish separately from marine fish. The initial Berwick Bank Wind Farm Proposal Scoping Opinion response has been considered for the development of this section.

6.2.2.    Study Area

369. Fish and shellfish are spatially and temporally variable, therefore for the purposes of the fish and shellfish ecology characterisation, two study areas are defined. These are shown in Figure 6.4  Open ▸ and described below:

• Proposed Development fish and shellfish study area encompasses the Proposed Development Proposed Development Array Area, proposed ECC and intertidal zone seaward of MHWS; and
• northern North Sea fish and shellfish study area encompasses the Proposed Development fish and shellfish study area and a surrounding area defined by the boundary of the northern North Sea as defined by the biogeographic region identified as part of the Review of Marine Nature Conservation (RMNC) (2004). This is the regional study area and also encompasses waters of the Forth and Tay Scottish Marine Region (SMR). The northern North Sea fish and shellfish study area provides a wider context for the fish species and populations identified within the Proposed Development fish and shellfish study area and will inform assessments of those impacts affecting fish and shellfish receptors over a larger scale (e.g. underwater noise).

6.2.3.    Baseline Environment

370. This section provides a concise summary of the fish and shellfish baseline environment of the Proposed Development, reference should be made to Appendix 8  Open where a detailed description is provided. In 2020, epibenthic 2 m beam trawling at 15 sampling locations distributed across representative sediment types was undertaken and this will inform the fish and shellfish baseline. The survey design was discussed and agreed with NatureScot and Marine Scotland in July 2020. This site-specific data along with the comprehensive desktop information and data sources available will aid the characterisation of the fish and shellfish baseline.

Figure 6.4: Fish and Shellfish Study Area

Designated Sites

371. Although the Proposed Development does not overlap with any European sites, there are several protected areas for fish in East Scotland, within the northern North Sea fish and shellfish study area. Apx. Table 8. 2  Open ▸ provides an early indication of the designated sites (international and national) that may be considered within the EIA and /or HRA. Information to support a full screening of European sites with qualifying fish and shellfish interest features will be provided in the LSE Screening Report. Relevant fish and shellfish interest features screened in will be fully considered and assessed in the fish and shellfish ecology Offshore EIAR section, with information to support the assessment of European sites and features provided in the Report to Inform Appropriate Assessment (RIAA).

Fish Assemblage

372. The fish assemblage of the northern North Sea fish and shellfish study area includes demersal, pelagic, migratory and elasmobranchs fish species. Demersal species include sandeel Ammodytidae, whiting Merlangius merlangus, lemon sole Microstomus kitt, ling Molva molva, plaice Pleuronectes platessa, with pelagic species including herring Clupea harengus, sprat Sprattus sprattus and saithe Pollachius virens likely to be found in the vicinity of the Proposed Development.
373. In August 2020, 15 epibenthic beam trawls were collected across the distributed across Proposed Development Array Area and ECC options. A total of 21 bony fish taxa representing 553 individuals were recorded from these epibenthic trawls undertaken across the Proposed Development benthic subtidal and intertidal ecology study area. The most abundant fish recorded in the trawls were common dab Limanda limanda (167 individuals), Long rough dab Hippoglossoides platessoides, lesser sandeel and gobies Pomatoschistus sp. This was consistent with the infaunal data collected which also recorded lesser sandeels. Lesser sandeel, common dab and long rough dab were recorded in trawls across the Proposed Development benthic subtidal and intertidal ecology study area, while Pomatoschistus sp. was only recorded in trawls within the Proposed Development ECC. Two four-bearded rockling Enchelyopus cimbrius and angler fish Lophius piscatorius were recorded across all trawls.
374. Further, to inform the fish and shellfish baseline characterisation for the Seagreen Alpha/Bravo EIA (Seagreen, 2012b), a total of 53 epibenthic trawls were conducted during the benthic surveys in 2011. Several species were observed including pogge Agonus cataphractus, dab Limanda limanda, goby Pomatoschistus norvegicus/lozanoi, lesser sandeel Ammodytes marinus, butterfish Pholis gunnellus, plaice, whiting and cod. Of these species, dab, goby, and lesser sandeel were generally the most abundant and with up to 588 individuals recorded in a single trawl. Commercial species such as plaice, whiting and cod were also observed. In addition, elasmobranchs (sharks and rays) have been found distributed throughout the east coast of Scotland (Coull et al., 1998; Ellis et al., 2012; Baxter et al., 2011).

Diadromous Fish Species

375. There is the potential for diadromous fish species to migrate to and from Scottish rivers in the vicinity of the Proposed Development and, therefore, they may migrate through the Proposed Development fish and shellfish study area to rivers during certain periods of the year (SNH, 2017a and National Biodiversity Network (NBN) Atlas, 2019).
376. The fish and shellfish ecology assessment for Seagreen Alpha/Bravo (Seagreen, 2018) observed seven migratory species of relevance: Atlantic salmon Salmo salar, sea trout Salmo trutta, sea lamprey Petromyzon marinus, river lamprey Lampetra fluviatilis, European eel Anguilla anguilla, Allis and twaite shad Allosa fallax and Allosa allosa and sparling (European smelt) Osmerus eperlanus. The species which were considered as having the greatest potential to be present within the vicinity of the Seagreen Alpha/Bravo were Atlantic salmon, sea trout, eels and the lampreys.
377. No site-specific surveys are proposed to inform the impact assessment on migratory fish species. For the purposes of the impact assessment, it will be assumed that the aforementioned species are likely to be present within the Proposed Development Array Area and/or proposed ECC, during key migration periods (e.g., adult migration to spawning rivers and smolt migration from natal rivers in the vicinity of the development).
378. With respect to migratory fish species, the aim of the impact assessment will be to determine whether construction, operation and maintenance or decommissioning activities have the potential to lead to disruption to migration, e.g., construction noise potentially creating an effective barrier to fish migration. The timing of fish migration will therefore be an important element of the baseline characterisation and this will be collected through desktop data sources, including rod catch data from rivers on the east coast of Scotland (e.g. Tweed, Forth, Tay, Esk and Dee), recent papers (e.g. Newton et al., 2017; Gardiner et al., 2018, Godfrey et al., 2015; Malcolm et al., 2015) and Marine Scotland smolt survey data from the east coast of Scotland (Marine Scotland, 2018c).

Shellfish Assemblage

379. Commercial landing data provides an overview of species present within the northern North Sea fish and shellfish study area. Species most caught include the brown crab Cancer pagarus, European lobster Homarus gammarus, great scallop Pecten maximus, velvet swimming crab Necora puber and squid Loligo spp. Other species caught in the area include green crab Carcinus maenas and whelks Buccinum undatum (ICES, 2018).
380. The River South Esk, River Dee and River Spey SACs have primarily been designated as SACs due to the presence of the freshwater pearl mussel Margaritifera margaritifera. The freshwater pearl mussel is dependent on the Atlantic salmon smolting population and therefore should the Atlantic salmon population be adversely affected by the Proposed Development; this may have an indirect effect on freshwater pearl mussel populations.
381. During the epibenthic trawls conducted for Seagreen Alpha/Bravo, several shellfish species were observed including great scallop and queen scallop Aequipecten opercularis (Seagreen, 2012b). Nephrops was also recorded during site-specific surveys for the Berwick Bank Wind Farm (including epibenthic beam trawls and seabed imagery). Underwater video survey data provided by Marine Scotland also showed that Nephrops abundance was high in the inshore waters of the southern parts of the spawning and nursery grounds (Seagreen, 2012b). Other species such as brown crab, lobster, velvet swimming crab, whelk and squid were either recorded in very low abundances or not observed at all in the in the benthic surveys but are all recognised as important commercial shellfish species within the northern North Sea fish and shellfish study area (Seagreen, 2018).
382. The Offshore EIAR will provide further discussion of the shellfish assemblage observed within the site-specific subtidal survey.

Spawning and/or Nursery Grounds

383. Potential nursery and spawning areas in the North Sea for a range of species were identified by Coull et al.(1998), based on larvae, egg and benthic habitat survey data. Ellis et al.(2012) reviewed this data for several fin fish species in the North Sea, including herring, providing an updated understanding of areas of low and high intensity nursery and spawning grounds. Herring and sandeel known spawning and nursery grounds identified within the Proposed Development fish and shellfish study area are illustrated in Figure 6.5  Open ▸ .
384. 349. Species with known spawning periods and nursery habitats identified within the Proposed Development fish and shellfish study area have been summarised in Apx. Table 8. 3  Open ▸ .

Figure 6.5: Herring and Sandeel Spawning and Nursery Grounds that Overlap with the Proposed Development

6.2.4.    Potential Proposed Development Impacts

385. A range of potential impacts on fish and shellfish ecology have been identified which may occur during the construction, operation and maintenance, and decommissioning phases of the Proposed Development in the absence of designed in measures:

• Construction

–           Temporary habitat loss and disturbance;

–           Underwater noise impacting fish and shellfish receptors;

–           Increased suspended sediment concentrations and associated sediment deposition; and

–           Accidental release of pollutants.

• Operation and Maintenance

–           Long-term habitat loss;

–           Temporary habitat loss;

–           Electromagnetic Fields (EMF) from subsea electrical cabling;

–           Accidental release of pollutants;

–           Underwater noise from wind turbine operation and vessels; and

–           Colonisation of hard structures.

• Decommissioning

–           Temporary habitat loss and disturbance;

–           Underwater noise impacting fish and shellfish receptors;

–           Increased suspended sediment concentrations and associated sediment deposition; and

–           Accidental release of pollutants.

6.2.5.    Designed in Measures

386. Designed in measures, and how these can reduce potential for impact have been considered in identification of impacts that have been scoped into the Proposed Development assessment (Table 6.5  Open ▸ ) and scoped out (Table 6.6  Open ▸ ) from further assessment. Measures adopted as part of the Proposed Development will follow good practice and may include:

• implementation of piling soft-start and ramp-up measures;
• development of, and adherence to, an appropriate CoCP;
• development of, and adherence to, an Environmental Management Plan, including Marine Pollution Contingency Plans; and
• development of, and adherence to, a Decommissioning Plan.
  387. The requirement for additional mitigation measures will be dependent on the significance of the effects on fish and shellfish ecology and will be consulted upon with statutory consultees throughout the EIA process and Road Map process – in particular potential mitigation required for marine fish such as herring (as a species particularly sensitivity to underwater noise). Likewise, potential for monitoring will be discussed via the Benthic, Fish and Shellfish, and Physical Processes Road Map.

6.2.6.    Potential Impacts after the Implementation of designed in measures

388. The impacts that have been scoped into the Proposed Development assessment are outlined in Table 6.5  Open ▸ together with a description of any additional data collection (e.g. site-specific surveys) and/or supporting analyses (e.g. modelling) that will be required to enable a full assessment of the impacts.
389. At this stage, a number of impacts are proposed to be scoped out of the assessment for fish and shellfish, described in Table 6.6  Open ▸ .

Table 6.5: Impacts Proposed to be Scoped In to the Proposed Development Assessment for Fish (Marine Fish and Diadromous Fish) and Shellfish. Project Phase Refers to Construction (C), Operation and Maintenance (O) and Decommissioning (D) Phase of the Proposed Development

 

Table 6.6: Impacts Proposed to be Scoped Out of the Proposed Development Assessment for Fish and Shellfish

 

6.2.7.    Proposed Approach to the Environmental Impact Assessment

390. The fish and shellfish EIA will follow the methodology set out in section 4  Open ▸ . Specific to the fish and shellfish EIA, the following guidance documents will also be considered:

• Guidelines for EcIA in the UK and Ireland. Terrestrial, Freshwater, Coastal and Marine (CIEEM, 2019);
• Consenting, EIA and HRA Guidance for Marine Renewable Energy Developments in Scotland (European Marine Energy Centre (EMEC) and Xodus, 2010) and
• Guidance on Environmental Considerations for Offshore Wind Farm Development (OSPAR, 2008).
  391. In addition, and specific to marine ecology topics, IEFs will be identified, in accordance with CIEEM (2019) guidelines, and assessments will be presented for appropriate ecological receptor groups in the baseline characterisation of each relevant technical section. Criteria defining the value of each IEF will be defined to reflect topic-specific interests, with reference to the CIEEM (2019) guidelines and will include specific consideration of Priority Marine Features (PMFs) within the fish and shellfish ecology study area.
  392. Additionally, a staged Marine Protected Area (MPA) assessment will be undertaken to assess the potential for the activities associated with the construction, operation and maintenance and decommissioning of the Proposed Development to hinder site conservation objectives. This MPA assessment will consider Marine Protected Areas with fish and shellfish features within or near the Proposed Development based on the outputs of a Stage 1 Screening Exercise, including the Firth of Forth Banks Complex Nature Conservation MPA (ncMPA) with regard to ocean quahog Arctica islandica.
  393. SSER will include diadromous fish in the fish and shellfish ecology impact assessment, and a separate section covering sensitivity of and implications of the impact on diadromous fish in each impact assessment. The approach and focus of these impact assessments will be discussed with stakeholders through the Benthic Ecology, Fish and Shellfish and Physical Processes Road Map process.
  394. The importance of fish species (such as herring, sandeels and sprat) as key prey species will be assessed in the relevant sections (section 6.4  Open ▸ : Ornithology, section 6.3  Open ▸ : Marine Mammals). These will be informed by the fish and shellfish ecology EIA section which will provide clear outputs over which to inform these assessments.
  395. Habitat suitability for sandeels and herring will be assessed using data collected as part of the benthic ecology survey in line with industry good practice guidelines with discussion with stakeholders via the Road Map process.
  396. A Fish and Shellfish Ecology Technical Report will present a detailed baseline characterisation for the Proposed Development using specific survey data and the most recent desktop data. This report will inform the Fish and Shellfish Ecology ES section.

Potential Cumulative Effects

397. The majority of predicted effects of construction, operation and maintenance, and decommissioning from the Proposed Development on fish and shellfish ecology are considered to be localised to within the footprint of the project. The key cumulative effect is likely to result from increased underwater noise during pile driving. The cumulative effects assessment will follow the approach outlined in section 4.3.7.

Potential Transboundary Impacts

398. A screening of transboundary impacts has been carried out and is presented in Appendix 3  Open . The potential for transboundary effects has been identified for fish and shellfish ecology receptors and will be considered within the EIAR.

6.2.8.    Scoping Questions to Consultees

• Do you agree with the study areas defined for fish and shellfish ecology?
• Do you agree that the existing desktop data on fish and shellfish resources in the fish and shellfish study area is sufficient to characterise the fish and shellfish baseline?
• Do you agree with the sites screened into the MPA Assessment (as presented in Appendix 17  Open )?
• Do you agree with the sites screened into the MPA Assessment (as presented in Appendix 17  Open )?
• Do you agree that all potential impacts (Table 6.5  Open ▸ ) have been identified for fish and shellfish ecology?
• Do you agree that the impacts described in Table 6.6  Open ▸ can be scoped out of the fish and shellfish ecology Offshore EIAR section?

6.2.9.    Next Steps

399. The following topic specific next steps as summarised below and will be undertaken through the Benthic Ecology, Fish and Shellfish and Physical Processes Road Map process:

• define the baseline environment and assessment approach:

–           discuss availability of datasets with District fisheries boards; and

–           present evidence base (including site-specific subtidal and intertidal surveys), baseline characterisation (including key marine fish, diadromous fish species, habitats and coastal processes) to stakeholders and agree on impacts and receptors to be scoped in/out of EIA Report.

• assessment of fish and shellfish ecology potential impacts through the EIA Report process:

–           present Maximum Design Scenarios and impact assessment approach including sensitivity of receptors, method of quantifying impacts to stakeholders; and

–           discuss initial findings of impact assessment, appropriate mitigation and monitoring with stakeholders.

400. Any impacts that cannot be quantitatively assessed will be discussed with key stakeholders as part of the Benthic Ecology, Fish and Shellfish and Physical Processes Road Map process.
401. Any potential need for strategic monitoring will be detailed in Fish and Shellfish Ecology section of the Offshore EIAR and will be discussed further with stakeholders through the Benthic Ecology, Fish and Shellfish and Physical Processes Road Map process.

 

6.3.        Marine Mammals

6.3.1.    Introduction

402.  This section of the Offshore EIA Scoping Report identifies the marine mammals of relevance to the Proposed Development and considers the potential impacts from the construction, operation and maintenance, and decommissioning of the offshore and intertidal components (seaward of the mean high water spring (MHWS) mark) of the Proposed Development on marine mammals.
403. Marine mammals were reported on in the initial Scoping Report. Although the change in project scope applied to this Scoping Report, which is combining the offshore Proposed Development Array Areas, the impacts are anticipated to generally be the same as identified in the initial Scoping Report. The SOR requested additional impacts were scoped in, such as injury and disturbance from underwater noise generated during clearance of unexploded ordnance (UXO) and disturbance to marine mammals from pre-construction surveys. The initial Berwick Bank Wind Farm Proposal Scoping Opinion response has been considered for the development of this section.

6.3.2.    Study Area

404. The marine mammal study area proposed for the purpose of the offshore EIA varies depending on the species, considering individual species ecology and behaviour. The marine mammal study area has been defined at two spatial scales:

• Proposed Development marine mammal study area: this includes the area covered by 2019 to 2021 site-specific marine mammal surveys which have been carried out for the Proposed Development. These will provide an indication of the marine mammals present across potential impact footprints (i.e. potential Zones of Influence (ZoI) associated with the Proposed Development). The area broadly encompasses the Proposed Development and export cable route plus a 16 km buffer. The Proposed Development marine mammal study area is shown in Figure 6.6  Open ▸ ; and
• Regional marine mammal study areas: marine mammals are highly mobile and may range over large distances and therefore to provide a wider geographic context, the desk top review will also consider the marine mammal ecology, distribution and density/abundance at the appropriate scales for each key species. In accordance with advice received during consultation (Initial Berwick Bank Wind Farm Proposal Offshore EIA Scoping Opinion, 2020), the Regional Marine Mammal Study Areas will be informed by species Management Unit (MU): cetacean MUs are defined by the Inter Agency Marine Mammal Working Group (IAMMWG, 2015) and seal MUs are provided by the Special Committee on Seals (SCOS, 2021). MUs will provide the baseline reference populations, inform the consideration of designated sites for marine mammals and help to identify cumulative projects. However, the site-specific (arial survey) data (as above) will define marine mammal presence in the study area. Where MUs for a given species extend over a very large scale (e.g., minke whale and white-beaked dolphin over the Celtic and Greater North Sea MU) the assessment will focus in on the appropriate SCANS-III Block (Block R) which overlaps the Proposed Development.

 

Figure 6.6: Marine Mammal Study Area

6.3.3.    Baseline Environment

405. This section provides a concise summary of the marine mammal baseline environment of the Proposed Development, reference should be made to Appendix 9  Open where a detailed description is provided. An initial desk-based review of literature and data sources to support this Offshore EIA Scoping Report has identified a number of baseline datasets. These are summarised in Appendix 9  Open . SSER is cognisant that Scottish Ministers have advised that all data sources, references of note and resources identified in the representation from NatureScot (NS) and the Marine Scotland Science (MSS) November Advice must be fully considered by the Developer (Initial Berwick Bank Wind Farm Proposal Offshore EIA Scoping Opinion, 2020). SSER will ensure all such information sources are considered.
406. Site-specific surveys for the Proposed Development have been carried out (2019 – 2021). These, along with surveys undertaken in the former Forth of Forth Zone in relation to Seagreen Phase 1 have informed the baseline environment characterisation outlined below.

Harbour porpoise

407. The most recent assessment of harbour porpoise Phocoena phocoena in UK waters concluded that the overall trend in Conservation Status was Unknown, highlighting that there was insufficient data to establish a trend for the population size nor potential future prospects for the population (JNCC, 2019b). The Proposed Development is located within the North Sea MU for harbour porpoise (IAMMWG, 2015), which is estimated to have an abundance of 346,601 porpoise (CV: 0.09, 95% CI: 289,498 – 419,96) (IAMMWG, 2021) based on estimates from the Small Cetaceans in the European Atlantic and North Seas (SCANS) III survey (Hammond et al., 2017; Hammond et al., 2021).
408. Hague (et al, 2020) present information on regional baselines for marine mammals across the North Sea and Atlantic areas of Scottish waters. The most recent broad scale data on harbour porpoise is reported to be that available from the SCANS III survey (Hammond et al.,2017) and the series of SCANS surveys between 1994 and 2016, although these only reflect summer distribution. These data suggest densities range of harbour porpoise from 0.058 porpoise/km2 in Block J (western Outer Hebrides) to 0.599 porpoise/km2 in Block R (east coast) (Hammond et al., 2017 cited in Hague et al., 2020).
409. Analyses of the count data from the site-specific (aerial) surveys indicate harbour porpoise densities in the study area are higher in the spring and summer months, with lower values in late autumn and winter (see Appendix 9  Open ). The overall mean relative density of harbour porpoise (estimated from data pooled across all transects and all months, with bootstrapping (1,000 simulations) was 0.10 animals per km2 (lower 95% CL: 0.026; upper 95% CL: 0.198). A relative high coefficient of variation (CV = 1.91) was calculated for mean monthly density, with high variance most likely to be a result of the large densities seen in May 2019 and April 2020. Once corrected for availability bias[6] (see Appendix 9  Open for full analysis) the mean corrected density estimate (from the bootstrapped average) across all monthly surveys for the aerial survey area was estimated as 0.24 animals per km2 (lower 95% CL: 0.063; upper 95% CL: 0.472).
410. Given the sightings recorded during the site-specific aerial surveys, and from previous surveys in the Firth of Forth Round 3 Zone, harbour porpoise is therefore considered likely to occur year-round within the Proposed Development marine mammal study area and wider potential ZoIs.

Minke whale

411. The most recent assessment of minke whale Balaenoptera acutorostrata in UK waters concluded that the overall trend in Conservation Status was Unknown, highlighting that there was insufficient data to establish a trend for the population size nor potential future prospects for the population (JNCC, 2019f). All minke whales in UK waters are considered to be part of the Celtic and Greater North Seas MU (IAMMWG, 2021), which is estimated to have an abundance of 20,118 whales (CV: 0.18, 95% CI: 14,061 – 28,786) based on estimates from the SCANS III survey (Hammond et al., 2017; Hammond et al., 2021) and the ObSERVE survey (Rogan et al., 2018).
412. During the site-specific surveys, minke whale was sighted in low numbers during the summer months only. Mean relative density and CV were therefore estimated from data collected during the months of May to August inclusive from the averaged densities in these months only. An overall mean of 0.004 animals per km2 (CV= 1.01) was calculated.
413. A visual tracking study of minke whale in Iceland recorded the time sequence of individual minke whales in terms of the duration when they were on the surface in between both short and long dive sequences (McGarry et al., 2017). Surfacing time was estimated as 58 s whilst dive duration was a mean of 73 s. Therefore, based on these data, availability bias would be approximately 0.44 and consequently absolute density can be approximated as 0.009 animals per km2.
414. For minke whale, the density estimates reported in Hague (et al., 2020) are sourced from SCANS II (Hammond et al., 2013) and CODA[7] (Macleod et al. ,2009), with the most recent broad scale data available cited (in terms of broad scale data) as that available from the SCANS III survey. With reference to these data (Hammond and Lacey (Appendix 3: SCANS surveys), density estimates in Scottish waters range from 0.008 to 0.039 minke whales/km2. Block R (the east coast) along with two other Blocks[8] was associated with the highest estimated densities. At sites (NE4 and NE5) within the Moray Firth, densities of >0.04 whale per km2 are predicted. Surface density estimates for North and East regions are noted to be particularly high (Hague et al., 2020).
415. Given the sightings recorded during the site-specific aerial surveys, and from previous surveys in the Firth of Forth Round 3 Zone, minke whales are considered likely to occur regularly in the summer months within the Proposed Development marine mammal study area and wider potential ZoIs.

White-beaked dolphin

416. The most recent assessment of white-beaked dolphins Lagenorhynchus albirostris in UK waters concluded that the overall trend in Conservation Status was Unknown, highlighting that there was insufficient data to establish a trend for the population size nor potential future prospects for the population (JNCC, 2019e).The relevant MU for white-beaked dolphins is the Celtic and Greater North Seas MU (IAMMWG, 2021), which has an estimated population size of 43,951 dolphins (CV: 0.22, 95% CI: 28,439 – 67,924) based on estimates from the SCANS III survey (Hammond et al., 2017; Hammond et al., 2021) and the ObSERVE survey (Rogan et al., 2018).
417. During the site-specific surveys, white-beaked dolphin was sighted in low numbers during the summer months only. Mean relative density and CV were therefore estimated from data collected during the months of June to September inclusive from the averaged densities in these months only. An overall mean of 0.004 animals per km2 (CV= 0.79) was calculated.
418. There is limited information on diving and surfacing times of white-beaked dolphin and consequently many studies report relative density estimates only (see Paxton et al., 2016). A bio-logging study of two individual free-ranging white-beaked dolphins in Iceland found that, on average, animals spent 18% of time close to the surface (0 to 2 m depth) and 82% of the time diving (Rasmussen et al., 2013). Therefore, based on these data, availability bias would be 0.18 and consequently absolute density can be approximated as 0.022 animals per km2. Given the sightings recorded during the site-specific aerial surveys, and from previous surveys in the Firth of Forth Round 3 Zone, white-beaked dolphins are therefore considered likely to occur regularly ( mostly likely in the summer months) within the Proposed Development marine mammal study area and wider potential ZoIs.

Bottlenose dolphin

419. The most recent assessment of bottlenose dolphins Tursiops truncatus in UK waters concluded that the overall trend in Conservation Status was Unknown, highlighting that although the population size appears to be stable, there were too few datapoints to confidently conclude on the current and future population trends (JNCC, 2019a).
420. The Moray Firth population of bottlenose dolphins is the only known remaining resident population in the North Sea and it was for this reason that the Moray Firth Special Area of Conservation (SAC) was established in order to protect this population. The current population estimate of bottlenose dolphin abundance for the Coastal East Scotland MU population is 189 dolphins (95% CI: 155 – 216) (IAMMWG, 2021), based on capture-mark-recapture photo-ID and calculated using a Bayesian model with 95% Highest Posterior Credible Interval for 2015 (Cheney et al., 2018).
421. In Hague et al. (2020) uniform densities estimates (based on SCANS III blocks) in Scottish waters ranged from 0.000 to 0.121 bottlenose dolphins per km2.
422. Due to the low number of sightings of bottlenose dolphin during the site-specific surveys, it was necessary to explore published density estimates, including previous site-specific data from Seagreen Alpha/Bravo or other Firth of Forth and Firth of Tay offshore wind farms (Neart na Gaoithe and Inch Cape) to inform the marine mammal baseline characterisation.
423. Given the presence of bottlenose dolphins within coastal waters in east Scotland, they are considered likely to occur regularly within the Proposed Development marine mammal study area and wider potential ZoIs.

Harbour seal

424. In the UK, harbour seals Phoca vitulina have been assessed as having an Unfavourable – Inadequate conservation status (JNCC, 2019d). The assessment concluded Unfavourable – Inadequate for population size as the short-term trend is unknown and the current population size is below the Favourable Reference Range. In addition, the future prospects were assessed as Unfavourable – Inadequate because the future prospects of the population are poor.
425. The Proposed Development is located within the East Scotland Seal MU and adjacent to the North East England MU. The most recent harbour seal August moult count presented for this East Scotland MU is 343 (2016-2019 count period) (SCOS, 2021), which can be scaled by the estimated proportion hauled-out (0.72, 95% CI: 0.54-0.88) (Lonergan et al., 2013) to provide an estimate of 476 harbour seals in the East Scotland MU in 2019 (95% CI: 390 - 635). The most recent (as reported in SCOS, 2020) August counts of harbour seals at haul-out sites in the Northeast England MU (Unit 8) reported for 2016- 2019 was 79. There recent count data at the Firth of Tay and Eden Estuary SAC shows no evidence that the population is recovering after the decline in the 2000s, and the 2019 SAC count is ~95% lower than the 1992 count (SCOS, 2021).
426. Due to the low number of sightings of harbour seal during the site-specific surveys, it was necessary to explore published density estimates, including previous site-specific data from Seagreen Alpha/Bravo or other Firth of Forth and Firth of Tay Offshore wind farms (Neart na Gaoithe and Inch Cape) to inform the marine mammal baseline characterisation.
427. Given the sightings recorded during the site-specific aerial surveys, from previous surveys in the Firth of Forth Round 3 Zone (Grellier and Lacey, 2012; Sparling, 2012), and from the seal telemetry and habitat preference maps (Carter et al., 2020), harbour seals are considered likely to occur year-round (primarily in coastal waters) within the Proposed Development marine mammal study area and wider potential ZoIs.

Grey seal

428. The most recent assessment of grey seals Halichoerus grypus in UK waters concluded that the overall trend in Conservation Status was Favourable, with an overall trend in Conservation Status assessed as Improving (JNCC, 2019c).
429. The most recent UK wide grey seal pup production count was in 2016 and 2018, which resulted in a modelled UK adult population size in 2019 of 149,700 grey seals (95% CI 120,000 – 174,900) (SCOS, 2021). Pup production in the North Sea region (which includes the Firth of Forth breeding colonies) increased rapidly between 2010 to 2016 (annual increase of 11.5% per annum), however the rate of increase has been slowing in more recent years (annual increase of 7.5% per annum between 2014 and 2018) (SCOS, 2021).
430. The Proposed Development is located within the East Scotland Seal MU where the most recent August count was 3,683 (between 2016-2019) (SCOS, 2021). This count can be scaled by the estimated proportion hauled-out (0.239, 95% CI: 0.192 – 0.286) (Russell et al., 2016) to produce an estimate of 15,410 grey seals in the MU (95% CI: 12,878 – 19,182). The Proposed Development is adjacent to the North-East England MU and the East Coast Scotland MU (SCOS, 2021).
431. Relative densities of grey seal (henceforth these include ‘seal species’) across the aerial survey area were, on average, very low for all seasons. Relative densities of grey seal peaked in May 2019 with a mean of 0.14 animals per km2 (lower 95% CL:0.073; upper 95% CL: 0.239). For all months (apart from May 2019) there was a very low sightings rate of grey seal including ‘seal species’, with less than 20 individuals recorded across all transects. As a result, the overall mean relative density of grey seal estimated from data pooled across all transects and all months was very low, with an average of 0.03 animals per km2 (lower 95% CL: 0.013; upper 95% CL: 0.044). Variance was high (CV = 1.402), most likely due to the high peak in sightings in May 2019.
432. Given the sightings recorded during the site-specific aerial surveys, from previous surveys in the Firth of Forth Round 3 Zone (Grellier and Lacey, 2012; Sparling, 2012), and from the seal telemetry and habitat preference maps (Carter et al., 2020), grey seals are considered likely to occur year round within the Proposed Development marine mammal study area and wider potential ZoIs.

Distribution of sightings

433. Sightings of marine mammals were spatially distributed throughout the aerial survey area. Figure 6.7  Open ▸ to Figure 6.10  Open ▸ show the distribution of the sightings overlaid on the transects flown each month (i.e., highlighting where there were missed transects and therefore no sightings data).

 

Figure 6.7: Distribution of Sightings of Marine Mammals in the Aerial Survey Area Overlaid on Transects Flown each Month: March, May, June and July 2019

Figure 6.8: Distribution of Sightings of Marine Mammals in the Aerial Survey Area Overlaid on Transects Flown Each Month: August, September and October 2019

Figure 6.9: Distribution of Sightings of Marine Mammals in the Aerial Survey Area Overlaid on Transects Flown Each Month: November 2019, December 2019 and January 2020

Figure 6.10: Distribution of Sightings of Marine Mammals in the Aerial Survey Area Overlaid on Transects Flown Each Month: February, March and April 2020

Designated Sites

434. The potential for LSE on European sites designated for marine mammals has been considered as part of the HRA for the Proposed Development. 24 European sites were considered at Stage one of the HRA process (screening) for relevant Annex II marine mammals likely to occur in the vicinity of the Proposed Development, as follows:

• 19 European sites for harbour porpoise;
• a single European site for bottlenose dolphin;
• two European sites for grey seal; and
• a single European site for harbour seal.
  435. The five European sites (relevant features and pathways) for which potential LSEs could not be discounted at the conclusion of the HRA screening exercise are set out in Table 6.7  Open ▸ . These sites will be considered further at the second state of the HRA process.

 

Table 6.7: Summary of European Sites and Relevant Qualifying Features for Which Potential LSEs Have Been Identified and Screened in for Further Assessment

 

6.3.4.    Potential Proposed Development Impacts

436. A comprehensive range of potential impacts on marine mammals have been identified which may occur during the construction, operation and maintenance, and decommissioning phases of the Proposed Development in the absence of designed in measures:

• Construction

–           Injury and disturbance from underwater noise during pile driving;

–           Injury and disturbance from underwater noise generated during clearance of unexploded ordnance (UXO);

–           Disturbance to marine mammals from pre-construction surveys;

–           Disturbance to marine mammals from vessel use and other construction related activities;

–           Injury of marine mammals due to collision with construction vessels;

–           Effects on marine mammals due to changes in prey availability;

–           Accidental pollution during the construction phase; and

–           Increased suspended sediment concentrations and associated sediment deposition.

• Operation and Maintenance

–           Electro-magnetic fields (EMF);

–           Disturbance to marine mammals from operational noise;

–           Disturbance to marine mammals from vessel use;

–           Injury to marine mammals from collisions with operation and maintenance vessels;

–           Effects on marine mammals due to changes in prey availability; and

–           Accidental pollution during the operation and maintenance phase.

• Decommissioning

–           Disturbance to marine mammals from vessel use and other decommissioning activities;

–           Injury to marine mammals from collisions with decommissioning vessels;

–           Effects on marine mammals due to changes in prey availability;

–           Accidental pollution during the decommissioning phase; and

–           Increased suspended sediment concentrations and associated sediment deposition.

6.3.5.    Designed in Measures

437. The following designed in measures, and how these can reduce potential for impact have been considered in identification of impacts that have been scoped into (Table 6.8  Open ▸ ) or out of (Table 6.9  Open ▸ ) the Proposed Development assessment.
438. Measures adopted as part of the Proposed Development will follow good practice and may include:

• the development of, and adherence to, an appropriate CoCP;
• the development of, and adherence to, an Environmental Management Plan, including Marine Pollution Contingency Plan;
• the development of, and adherence to, a Piling Strategy (PS);
• development of, and adherence to, a Vessel Management Plan (VMP);
• use of low order deflagration to clear all UXOs;
• development of, and adherence to, a Marine Mammal Mitigation Protocol (MMMP - geophysical survey specific);
• implementation of piling soft-start and ramp-up measures;
• development of, and adherence to, a Marine Mammal Mitigation Protocol (MMMP - piling specific); and
• implementation of a Decommissioning Plan.
  439. The requirement for additional mitigation measures will be dependent on the significance of the effects on marine mammals and will consider best available evidence, including any outputs from work undertaken during construction of other wind farm, and will be consulted upon with statutory consultees throughout the Marine Mammal Road Map process.

6.3.6.    Potential Impacts after the Implementation of designed in measures

440. The impacts that have been scoped into the Proposed Development assessment are outlined in Table 6.8  Open ▸ together with a description of any additional data collection (e.g. site-specific surveys) and/or supporting analyses (e.g. modelling) that will be required to enable a full assessment of the impacts.
441. At this stage, potential impacts to marine mammals have been scoped out of the assessment, described in Table 6.9  Open ▸ .

 

Table 6.8: Impacts Proposed to be Scoped In to the Proposed Development Assessment for Marine Mammals. Project Phase Refers to Construction (C), Operation and Maintenance (O) and Decommissioning (D) Phase of the Proposed Development

 

Table 6.9: Impacts Proposed to be Scoped Out of the Proposed Development Assessment for Marine Mammals

 

 

6.3.7.    Proposed Approach to the Environmental Impact Assessment

442. The marine mammal offshore EIA will follow the methodology set out in section 4  Open ▸ . Specific to the marine mammal EIA, the following guidance documents will also be considered:

• Institute of Ecology and Environmental Management (IEEM) guidelines for marine and coastal ecological impact assessment in Britain and Ireland (IEEM, 2010, CIEEM, 2019);
• European Union Guidance on wind energy developments and Natura 2000 legislation (European Commission, 2010);
• Oslo Paris Convention (OSPAR) Guidance on Environmental Considerations for Offshore Wind Farm Development (OSPAR, 2008); and the marine mammal injury noise exposure-onset noise exposure criteria recommended in Southall et al., (2019).
  443. The impact assessment will consist of a detailed quantitative assessment for underwater noise (pile driving, geophysical surveys and vessel noise). The assessment will include permanent auditory injury and behavioural disturbance. The risk of injury will be based on both of the dual criteria: cumulative sound exposure level (SELcum) and peak sound pressure level (peak SPL). To assess the SELcum criterion, the predictions of received sound level over 24 hours are frequency weighted, to reflect the hearing sensitivity of each functional hearing group. The peak SPL criterion is for unweighted received sound level. The assessment of disturbance will be based on the good practice methodology at the time of assessment, and, where possible, will include consideration of species-specific dose-response curves. Noise contours at appropriate intervals will be generated by noise modelling and overlain on species density surfaces to predict the number of animals potentially disturbed. This will allow the quantification of the number of animals that potentially will respond.
  444. The densities to be used in the assessment process for assessing potential impacts on harbour seals, and agreement of correction factors for availability bias will be discussed with stakeholders as part of the Marine Mammal Road Map process.
  445. In addition, and specific to marine ecology topics, IEFs will be identified and assessments will be presented for appropriate ecological receptor groups in the baseline characterisation of each relevant technical section. Criteria defining the value of each IEF will be defined to reflect topic-specific interests.

Potential Cumulative Effects

446. For marine mammal receptors the approach to cumulative impact assessment will be holistic and combine all potential sources of underwater noise including:

• pile driving,
• disturbance from vessels,
• UXO clearance,
• seismic surveys, and
• any other offshore construction developments that are planned within the relevant MUs for each species.
  447. The key cumulative effect is likely to come from underwater noise from pile driving. A range of realistic scenarios for cumulative underwater noise effects will be developed for the cumulative effects assessment, based on publicly available information, liaison with other developers where possible, as well as consultation with the regulators and stakeholders.
  448. The impacts of fishing and shipping will not be considered in the cumulative effects assessment since these activities occur throughout the baseline and are therefore already accounted for in the existing marine mammal baseline characterisation abundance and density estimates.
  449. The cumulative effects assessment will follow the approach outlined in section 4.3.7.

Potential Transboundary Impacts

450. A screening of transboundary impacts has been carried out and is presented in Appendix 3  Open . No potential transboundary effects have been identified for marine mammals and therefore this will not be considered within the EIAR.

6.3.8.    Scoping Questions to Consultees

• Do you agree that the existing data available to describe the marine mammal baseline is sufficient to describe the environment in relation to the Proposed Development?
• Do you agree that the designed in measures described provides a suitable means for managing and mitigating the potential effects of the Proposed Development on the marine mammal receptors?
• Do you agree that the impacts listed in Table 6.8  Open ▸ cover the impacts that should be assessed in the impact assessment for marine mammals?
• Do you agree with the sites screened into the MPA Assessment (as presented in Appendix 17  Open )?
• Do you agree that the impacts listed inTable 6.9  Open ▸ can be scoped out of the Proposed Development EIA?

6.3.9.    Next Steps

451. The following topic specific next steps as summarised below and will be undertaken through the Marine Mammal Road Map process:

• baseline characterisation;

–           seek agreement from stakeholders on species, abundance and density estimates taken forward to the impact assessment.

• seek agreement with stakeholders on the approach to and parameters to be used in subsea noise modelling including

–           modelling locations;

–           pile types;

–           maximum hammer energy and duration;

–           soft start and ramp up hammer energies and durations;

–           number of piles to be installed in one day; and

–           occurrence of concurrent piling (two piling operations occurring on the same day).

•  undertake ongoing stakeholder engagement throughout the pre-application phase including seeking agreement on densities to be used in the assessment process for assessing potential impacts on harbour seals, and appropriate correction factors for availability.
  452. Further, there will be discussion around the additional mitigation measure such as the use of Marine Mammal Observers (MMOs) and Acoustic Deterrent Device (ADD).

 

6.4.        Offshore and Intertidal Ornithology

6.4.1.    Introduction

453. This Offshore EIA Scoping Report considers the potential impacts on birds from construction, operation and maintenance, and decommissioning of the offshore and intertidal components of the Proposed Development (seaward of the MHWS mark).
454. An assessment of offshore and intertidal ornithology was included in the Initial Berwick Bank Offshore EIA Scoping Report. There have been subsequent changes in the Proposed Development area and project description (as described in Section 3) and this has been applied to this Berwick Bank Offshore EIA Scoping Report. These changed include:

• Increasing the minimum blade to tip clearance from 22 m to 37 m (above LAT) in order to minimise impacts to key species such as kittiwake and gannet;
• Refinement of the site boundary to avoid relative ‘hot spot’ areas for key species such as guillemot and kittiwake towards the north of the Array Site;
• Implementing a minimum 4 km buffer between Seagreen Wind Farm to minimise possible barrier effects.
  455. The initial Berwick Bank Scoping Opinion response has been considered in developing this section. As a result of this review, additional impacts have been scoped in including potential impacts resulting from temporary disturbance during export cable installation activities.

6.4.2.    Offshore Ornithology Study Area

456. Three study areas inform the Offshore Scoping Report (and subsequently the Offshore EIAR). These are listed below, with further detail provided in the following sections:

• Offshore Ornithology Regional Study Area;
• Offshore Ornithology Study Area; and
• Intertidal Ornithology Study Area.

Offshore Ornithology Regional Study Area

457. he offshore ornithological regional study area was determined by the area within which potential impacts to breeding seabirds could occur and was based on the foraging ranges of breeding seabirds. Many seabirds have large foraging ranges which extend several hundred kilometres from their breeding colonies. Birds may therefore overlap (i.e. have connectivity with) the Proposed Development, even when the colonies they originate from are a significant distance away. The offshore ornithology regional study area therefore identifies the SPA breeding colonies with potential connectivity to the Proposed Development (Figure 6.11  Open ▸ ).
458. Published mean-maximum foraging ranges (plus one standard deviation (+1 S.D.)) in Woodward et al. (2019) were used to define the offshore ornithology regional study area. Northern gannet Morus bassanus has the largest foraging range (315.2 km ± 194.2 km) of the key species considered in the ornithology assessment. The offshore ornithology regional study area therefore extends 509.4 km from the Proposed Development (Figure 6.11  Open ▸ ). Search areas for SPA breeding colonies and regional search areas for other key species in the assessment will fall within the mean-maximum foraging range of gannet. Therefore, this approach is appropriate to define the maximum extent of the offshore ornithology regional study area.
459. A seabird breeding colony that is affected by the potential impacts of the Proposed Development could also be affected by the potential impacts at other developments within the foraging range of seabirds from that colony. The offshore ornithology cumulative study area for each species will therefore be defined by implementing a search area equivalent to the species-specific mean-maximum foraging range (+ 1 S.D.) along a marine pathway, from those potentially affected breeding colonies of that species.
460. In the non-breeding season, seabirds are not constrained by colony location and can, depending on individual species, range widely within UK seas and beyond. The Zone of Influence (ZoI) for seabird species in the non-breeding season (where an assessment is deemed to be required) is based on Furness (2015) which presents Biologically Defined Minimum Population Scales (BDMPS). It is not possible to represent these scales on a figure.

Offshore Ornithology Study Area

461. The aerial survey area encompasses the Proposed Development Proposed Development Array Area, plus a 16 km buffer, which makes up the Offshore Ornithology Study Area (Figure 6.12  Open ▸ ). For the purposes of the assessment on bird impacts data obtained within the 16 km buffer area will be used.
462. Using this extensive study area will provide a wide ornithological context for the Proposed Development. It is also an appropriate size to provide a robust pre- and post-construction comparison of seabird abundance and distribution along a gradient outward from the proposed development and to allow this to be monitored.
463. The proposed export cable corridor beyond the 16 km buffer area is not included in the digital aerial survey area. Based on the predicted level of impact arising from cable laying on seabirds the use of existing data sources is considered sufficient to characterise baseline characteristics of the proposed export cable corridor for the purposes of the EIAR.
464. The offshore ornithology assessment will also include consideration of the potential impacts on migratory species.

Intertidal Ornithology Study Area

465. The study area for the assessment of effects on birds in the intertidal zone covers the coastal area between MHWS and MLWS at the landfall locations within which intertidal bird surveys have been carried out in the non-breeding season. This study area extends approximately 6km along the coast to cover both landfall locations and extends up to 1.5 km seaward from MHWS, encompassing the whole of the inter-tidal area (Figure 6.13  Open ▸ ).

6.4.3.    Baseline Environment

466. There is a considerable amount of information on seabirds and other birds in the outer Firth of Forth. These data are available following surveys and data collection programmes associated with the existing Forth and Tay offshore wind farm developments including: Seagreen 1 (Seagreen Alpha and Bravo), Neart na Gaoithe and Inch Cape offshore wind farms. However, guidelines and best practice applicable to the assessment of potential impacts of offshore wind farms on bird receptors are continually developing. Therefore, further site-specific baseline ornithological data collection has been undertaken between March 2019 and April 2021. Ongoing consultation with Marine Scotland (MS), NatureScot (NS) and the Royal Society for the Protection of Birds Scotland (RSPB) has informed the range of data collection to date and will continue to help to inform the scope of the analysis and assessment of the Proposed Development in the Offshore EIA Report. Details of the key desktop reports and site-specific surveys which inform the ornithology scoping assessment are given in Appendix 10  Open .

Figure 6.11: Offshore Ornithology Regional Study Area

Figure 6.12:  Offshore Ornithology Study Area

Figure 6.13: Intertidal Ornithology Study Area

 

 

Baseline Characterisation

467. The Proposed Development lies within the Forth and Tay region, recognised as one of the most important areas for birds in the North Sea (Heath et al. 2000). The Forth and Tay region supports internationally important populations of gannet, auk and gull species, and as a result, has been the focus of extensive seabird research. This has demonstrated the importance of the shallow sand banks of the Wee Bankie and Marr Bank as feeding areas for seabirds from local colonies such as the Isle of May (e.g. Daunt et al. 2011a; Wanless et al. 1998), and demonstrated that, in general, seabird numbers and species diversity decline with distance from shore.
468. As a result of this research, seabird distribution and abundance of the Proposed Development and surrounding area is known in part from previous surveys, reports and scientific studies (e.g. Kober et al., 2010). However, new information has become available through a combination of site-specific and regional research projects, as detailed above. An interim baseline report has been produced which summarises the existing baseline information (based upon the 19 months of aerial data analysed to date), updating and describing the current baseline knowledge on key species and trends in their population and distribution. Consultation on the Interim Baseline Report was undertaken in July – August 2021 with Marine Scotland, NatureScot and RSPB Scotland. Comments received in response to consultation on the Interim Baseline Report will be considered when preparing the final baseline report. The following provides a summary of general baseline characteristics of seabirds in the vicinity of the Proposed Development, divided into breeding, wintering and passage periods. Further detail is provided in Appendix 10  Open .

Breeding Season

469. Survey data to date indicate that the most numerous species in the offshore ornithology study area during the breeding season are gannet, kittiwake, guillemot, razorbill and puffin. For these species, numbers are typically highest during the pre-breeding period when birds forage further from their breeding colonies and during post -breeding dispersal.
470. Although there is considerable spatial variation in abundance and distribution within and between breeding seasons, published literature suggest relatively higher auk densities occur in the shallower waters of the Wee Bankie / Marr Bank sand bank complex in the west of the Proposed Development (Skov et al. 1995). Higher kittiwake densities have ranged further east (Daunt et al., 2011a, 2011b) but recent boat and aerial surveys indicate other foraging areas, for example in the south west of the Offshore Ornithology Study Area.
471. The Proposed Development lies within the core foraging range of gannets from the Bass Rock colony. Numbers of gannet at the Bass Rock colony have increased significantly in recent years, and this internationally important gannetry is now the largest in the world, with approximately 75,000 pairs (Murray et al., 2015).
472. Other species such as fulmar, herring gull, lesser black-backed gull and great black backed gull are distributed uniformly across the region at low densities during the breeding season. Species such as skuas and Manx shearwaters have not been recorded in surveys in the Offshore Ornithology Study Area in notable numbers in the breeding season.
473. The abundance of the key species above (gannet, kittiwake and auks) is consistent with the presence of internationally important breeding seabird colonies around the coast and islands of the Firths of Forth and Tay, in particular the Forth Islands SPA, which includes the Isle of May and Bass Rock, and the sea cliffs of St Abb’s Head to Fast Castle SPA and Fowlsheugh SPA. The breeding success of some species at these colonies is in decline reflecting what appear to be general trends for seabirds in the North Sea (Mavor et al., 2008; Parsons et al., 2008; JNCC, 2020). The proposed ECC runs through the Outer Firth of Forth and St Andrew’s Bay Complex SPA designated for breeding and non-breeding seabirds and waterfowl.

Non-Breeding Season

474. Surveys in the Offshore Ornithology Study Area indicate that in the non-breeding season, auks remain the dominant species group, although puffins are present in lower numbers than during the breeding period. Greater numbers of little auks, a winter visitor to the region, have also been recorded at this time. Kittiwakes are also widespread together with wintering herring and great black-backed gulls, including birds of Scandinavian origin. Gannets remain present but in reduced numbers as birds from the Bass Rock tend to winter in waters south of the UK, predominantly off West Africa (Deakin et al. 2019). By contrast, fulmars may be present in greater densities than in summer in the Firth of Forth area (Kober et al., 2010).
475. Seaducks, divers, grebes and waders which winter in the inner Firths of Forth and Tay in nationally important numbers appear to be present only in very low numbers further offshore.

Spring and Autumn Passage Periods

476. Passage movements in spring and autumn have traditionally been difficult to assess comparatively, using boat-based or aerial survey methods, as they generally occur over relatively short periods and therefore may be missed by surveys only undertaken once a month. Migration may also take place at high altitudes and at night when visual detection is difficult. This has been resolved to a degree for some species through satellite tagging individuals (notably bean goose and barnacle goose, for example see Wildfowl and Wetlands Trust (2017) although sample sizes remain relatively small and therefore only provide a partial indication of these species’ movements.
477. Migrating species were, nonetheless, still recorded during boat-based surveys in the Offshore Ornithology Study Area, particularly pink footed geese and a smaller number of barnacle geese. Overall, the relatively low numbers seen and evidence from tracking projects suggest that goose migration tends to occur predominantly inshore of the proposed Development (Griffin et al., 2011).
478. Other passage species occurring in relatively high numbers during boat-based surveys include little gulls and Arctic terns with common and Sandwich terns also recorded on passage in smaller numbers. Shearwaters and petrels which may have been anticipated on passage have been seen in relatively low numbers, as have skuas and gulls.
479. The SPAs of the inner Firths of Forth and Tay support large populations of species including sea ducks, divers, grebes and waders on passage, but these have not been regularly recorded on surveys in the Offshore Ornithology Study Area other than as isolated individuals. Passerine species are known to cross the North Sea in spring and autumn in large numbers, moving to and from continental Europe. However, there have been relatively few sightings of passerines from the surveys undertaken within the Offshore Ornithology Study Area with redwing being the most frequently recorded species occurring during autumn passage.
480. Overall, the aerial and boat-based data collected to date broadly confirm the distribution of key species predicted for the Firth of Forth region using European Seabirds at Sea (ESAS) data (Kober et al., 2010).

Intertidal Seasonal Variation

481. Intertidal and near-shore bird populations recorded during intertidal surveys vary seasonally, across the breeding, wintering and passage periods, although highest numbers were recorded during winter and passage, with relatively low numbers of individuals and species recorded in the breeding season (See Appendix 10  Open for further details).
482. The choice of preferred export cable landfall location (Skateraw or Thorntonloch) is yet to be finalised. However, for both options the export cable corridor passes through the Outer Firth of Forth and St Andrews Bay Complex SPA, the boundary of which follows the Mean Low Water Springs (MLWS) mark (Figure 6.13  Open ▸ ). The Skateraw landfall location overlaps Barns Ness Coast SSSI which is designated for geological feature and biological features (saltmarsh, sand dune and shingle); the citation also notes that a good diversity of birds adds to the interest of the site. Oystercatcher was the most abundant and regularly present wader species throughout the Intertidal Study Area, with typical numbers between 10 and 60 individuals. Turnstone, curlew, dunlin, redshank and ringed plover were also recorded regularly in lower numbers.

Designated Conservation Sites for Birds

483. A full screening of European designated sites with qualifying bird species will be undertaken in the LSE Screening Report for the Proposed Development which is planned to be submitted to MS-LOT in October 2021. Relevant qualifying species of European designated sites screened into the ornithology assessment will be fully considered and assessed in the Offshore EIA Report section with the assessment on the European designated sites itself deferred to the report to inform the Appropriate Assessment (RIAA).
484. Designated sites including SPAs, proposed SPAs (pSPA) and Ramsar sites, will be identified through the process described for identification of the offshore ornithology regional study area This will generate a ‘long-list’ of designated sites with potential connectivity to the Proposed Development derived from the relevant species foraging ranges (mean-maximum + 1 S.D.). Due to their proximity to the Proposed Development and based on the experience of Seagreen 1 and other Forth and Tay offshore wind farm developments, the assessment is likely to focus on the potential effects on:

• Forth Islands SPA;
• Fowlsheugh SPA;
• St Abb’s Head to Fast Castle SPA; and
• Outer Firth of Forth and St Andrew’s Bay Complex SPA.
  485. However, it is also recognised that there will be many other colonies, including designated sites, that could be impacted by both project alone and cumulatively/in-combination. The LSE Screening Report and subsequent RIAA will provide full details of the relevant sites, features and possible effects.
  486. Recent colony counts for the key seabird species at these SPAs are presented in Appendix 10  Open . The screening to be undertaken in the Offshore Ornithology EIA Report section will also include national designations, including SSSIs and MPAs.

6.4.4.    Potential Proposed Development Impacts

487. A range of potential impacts on offshore and intertidal ornithology have been identified which may occur during the construction, operation and maintenance, and decommissioning phases of the Proposed Development in the absence of designed in measures. These include:

• Construction:

–           Temporary Habitat Loss and Disturbance;

–           Indirect Impacts from construction noise;

–           Indirect impacts from UXO clearance;

• Operation and maintenance:

–           Collision impacts with wind turbines;

–           Disturbance and Displacement from maintenance vessels and the physical presence of the wind turbines;

–           Barrier to movements; and

• Decommissioning (similar to construction effects):

–           Temporary Habitat Loss and Disturbance;

–           Indirect Impacts from decommissioning noise;

488. The impacts that have been scoped into the Proposed Development assessment are outlined in Table 6.10  Open ▸ together with a description of any additional data collection (e.g. site-specific surveys) and/or supporting analyses (e.g. modelling) that will be required to enable a full assessment of the impacts.

6.4.5.    Designed in Measures

489.  Measures adopted as part of the Proposed Development include:

• the draught gap, i.e. the gap between the lower blade tip and the sea surface has been raised to 37 m above LAT, significantly reducing the potential number of collisions for key species including kittiwake and gannet;
• the boundary of the Proposed Development Array Area has been refined and has decreased the area by 128 km2, which reduces the area of potential displacement and barrier effects;
• the development of, and adherence to, a Vessel Management Plan (VMP);
• use low-order deflagration to clear UXOs where necessary; and
  490. the development of, and adherence to, an Environmental Management Plan, including Marine Pollution Contingency Plan.The requirement and feasibility of additional measures will be dependent on the significance of the effects on offshore and intertidal birds and will be consulted upon with statutory consultees throughout the EIA process, including as part of the Ornithology Road Map process.

6.4.6.    Potential Impacts after the Implementation of designed in measures

491. The impacts that have been scoped into the Proposed Development assessment are outlined in Table 6.10  Open ▸ together with a description of any data collected (e.g. site specific surveys) and/or supporting analyses (e.g. modelling) that may be required to enable a full assessment of the impacts.
492. Preliminary analysis of the digital aerial survey data, as well as the key species identified by the Forth and Tay Regional Advisory Group ornithology subcommittee, suggest that the seabird species on which the assessment will primarily be focussed on for the Proposed Development are:

• Gannet;
• Herring gull;
• Lesser black-backed gull;
• Kittiwake;
• Arctic tern;
• Guillemot;
• Razorbill; and
• Puffin.
  493. A brief summary of the interim analysis of survey data for each of these species is presented in Appendix 10  Open . In addition to the species listed above, all qualifying species for any SPAs that could be impacted will also be subject to a detailed assessment. All other species that were recorded less frequently and at lower densities within the offshore ornithology study area may not be assessed in as much detail as the key species listed above. In 2021 storm petrels were confirmed to be breeding on the Isle of May for the first time, with an estimated less than 20 pairs breeding on the island. Although there were no sightings of storm petrel during any of the aerial surveys the presence of this species in the region will be recognised in the EIAR.
  494. The level of assessment required for all species will be considered and discussed in the EIAR.
  495. It is proposed that collision risk will primarily be focussed on gannet, kittiwake, herring gull, lesser black-backed gull and Arctic tern, whilst displacement and barrier impacts will primarily be focussed on gannet, kittiwake, guillemot, razorbill and puffin. This will be kept under review as further evidence emerges on the potential effects of offshore wind farm developments on these and other species.
  496. The offshore EIA approach will also consider the wider ecosystem characteristics of the Proposed Development area by drawing together information on environmental and biological drivers of seabird abundance and distribution, where available. This will include particular consideration of the relationships between seabird distribution and prey availability and distribution, as well as the physical influences of bathymetry, tidal conditions and distance from colonies. Where information is available on changes to prey abundance following wind farm construction, this will also be incorporated into the ecosystem assessment. The ecosystem characteristics analysis will be discussed and agreed as part of the Ornithology Road Map process, and Ecosystem Approach Technical Report will be produced and included as an appendix to the final EIAR.
  497. Pollution impacts during all phases of the Proposed Development are scoped out on the basis that designed in measures, e.g., the implementation of agreed pollution prevention plans, will avoid the risk of significant pollution events. Consequently, seabirds and shorebirds are extremely unlikely to be impacted by any such pollution impacts.

 

 

Table 6.10: Impacts Proposed to be Scoped In to the Proposed Development Assessment for Offshore and Intertidal Ornithology

 

 

6.4.7.    Proposed Approach to the Environmental Impact Assessment

498. The offshore and intertidal ornithology EIA will follow the methods set out below. The offshore and intertidal EIA will be supported by a number of technical appendices including:

• Baseline report;
• Collision Risk Modelling;
• Displacement;
• Apportioning;
• Population Viability Analysis
• Ecosystems Approach.
  499. Sources of guidance and information to inform the ornithological assessment will be identified and the offshore and intertidal ornithology Offshore EIA Report section will detail all guidance considered in the preparation of the assessment. Emerging guidance will be monitored and applied as appropriate to the assessment and in discussion with consultees, including as part of the Ornithology Road Map process. These will be applied where possible within the internal Proposed Development programme for application for consent submission.

Seasonality

500. The length of the breeding and non-breeding seasons varies between seabird species. For identified sensitive seabird species, the breeding and non-breeding periods that will be used in the offshore EIA analysis will follow NS seasonal definitions (NatureScot 2020). The phenological periods for each species that will be considered in the offshore EIA scoping report are listed in Table 6.11  Open ▸ . Where the season is defined as occurring halfway through a month (e.g. kittiwake breeding and non-breeding seasons in March), the same density value for that month will be used for each season that is affected and the number of days split across each season.
501. The definitions and combinations of seasons (e.g., pre-breeding and breeding, post-breeding and non-breeding) to be used in the offshore EIA report will be subject to further discussion and agreement with consultees through the Ornithology Road Map process; similarly, the treatment of half-months need consideration with regard to the derivation of seasonal peak-mean values used in displacement analysis.

 

Table 6.11:  Seasonal Definitions for Seabird Species

 

Seabird Populations

502. The breeding seabird populations used will be based on the latest published data from the Seabird Monitoring Programme (SMP) online database (BTO, 2021) with non-breeding seabird populations derived from the zones determined by the BDMPS report (Furness, 2015). Most recently available colony populations for the key seabird species at the four key SPAs are presented in Appendix 10  Open .

Seabird Foraging Ranges and Connectivity

503. In order to determine connectivity between SPA colonies and the Proposed Development, the mean-maximum +1 SD (standard deviation) foraging ranges by Woodward et al. (2019) will be used (Table 6.12  Open ▸ ).
504. It may be that just the mean or mean-maximum value will be used for apportioning, depending on the number of sites considered to have connectivity to the development. The apportioning of birds will be undertaken based on the appropriate foraging ranges agreed through the Ornithology Road Map process.

 

Table 6.12:  Mean-maximum and Maximum Foraging Ranges of Identified Sensitive Species (Woodward et al., 2019)

 

Displacement and Barrier Effects

505. Displacement and barrier effects will be assessed using the SNCB recommended matrix methods (JNCC, 2017) and the use of SeabORD (Searle et al., 2018) for species with available tracking data to parameterise the model.
506. Seabird densities will be based on estimated densities derived from the March 2019 to April 2021 aerial survey data. The mean-peak population abundances within the offshore Proposed Development Array Area and a surrounding 2 km buffer for each season and for species identified as potentially vulnerable to displacement will be derived from estimated densities of birds on the water and in flight, either from MRSea model estimates or from design-based abundance estimates (depending on the functionality of the MRSea model which is subject to discussion at Road Map meetings).
507. Species for which detailed assessment of displacement impacts will be undertaken are: gannet, kittiwake, guillemot, razorbill and puffin. Displacement impacts will be assessed based on the whole year.
508. To assess impacts from displacement on auk species in the breeding season, the assessment area and regional populations will be derived using Woodward et al., (2019) mean-maximum foraging ranges. In the non-breeding season the BDMPS will be applied (except for guillemot where, due to their more localised wintering distribution compared to other breeding seabirds in the region, the assessment area and regional population will be based on breeding season estimates).
509. The SeaBORD displacement assessment tool (Searle et al., 2018) will be used for assessing displacement for kittiwake, guillemot, razorbill and puffin during the breeding season. During the non-breeding seasons displacement effects on these and other species will be assessed using the SNCB interim recommended approach (JNCC, 2017). Based on the mean maximum densities, the full range of potential level of displacement and mortality will be presented ranging from 0% to 100%. The level of displacement and mortality to be used for assessment will vary between species (Table 6.13  Open ▸ ). This approach follows that taken in previous offshore wind farm developments in the region (e.g. Seagreen 2018). Outputs from both methods will be presented and compared in the assessment.
510. Suitable displacement and mortality rates will be discussed and agreed with consultees during the development of the displacement assessment together with new relevant techniques, as part of the Ornithology Road Map process. In addition, further discussion on how to assess gannet displacement and barrier effects will also be required as part of the Road Map process.

 

Table 6.13: Proposed Parameters to be Used in the Assessment of Displacement Impacts

 

Collision Risk

511. The predicted collision risk to birds will be analysed using two collision risk modelling (CRM) techniques. Collision risk modelling will be undertaken for gannet, kittiwake, herring gull, lesser black-backed gull and other species depending on data analysis / abundance. The monthly densities of flying birds derived from the aerial surveys will be used to populate the offshore deterministic Band model (2012) and the Stochastic Collision Risk model (sCRM) developed by Masden (2015) and MacGregor et al. (2018). The results from the sCRM will be relied upon and used in further analysis following MSS advice, with the sCRM allowing for the variation and uncertainty surrounding the input parameters to be accounted for during modelling. The results from the deterministic Band model will be used for contextual and comparative purposes. Models will be run using Option 2 (Basic model) and Option 3 (Extended model) of the Basic and Extended Band (2012) Model.
512. Option 2 and Option 3 will utilise generic flight height distributions from Johnston et al. (2014). Further discussion and agreement on the use of the Band model Option 4 is required, as Option 4 utilises evidence-based flight height distributions from site-specific aerial/boat-based surveys. Further discussion with consultees is needed to agree on the appropriate source for evidence-based site-specific flight heights to ensure values used are robust and representative.
513. Collision risk outputs from all Options modelled will be presented alongside each other for comparative purposes.
514. Cook (2021) presents revised avoidance rates that for many species are lower than those previously published. No formal advice has been received on the use of these rates and they may be amended following any future peer review. Collision risk modelling using previously published avoidance rates will also be undertaken and the results presented for comparative purposes. Deterministic and stochastic avoidance rates to be used in the modelling are presented in Table 6.14  Open ▸ .Discussions with consultees through the Ornithology Road Map process will determine the finalised avoidance rates and modelling options to be used.

 

Table 6.14:  Avoidance Rates for Use in Collision Risk Modelling

* note avoidance rates for Arctic tern for Cook 2021 are for all tern species.

 

515. Morphological and behavioural parameters for the key species have been derived from literature and are summarised in Table 6.15  Open ▸ . Body length and wingspan were taken from Robinson (2005) and flight speeds from Pennycuick (1997) and Alerstam et al. (2007). Evidence-based in-field flight speeds obtained by Skov et al. (2018) have been presented alongside literature derived flight speeds and will be used in the assessment for comparative purposes. It is recognised that flight speeds may be updated following publication of forthcoming studies.
516. Nocturnal activity scores for kittiwake have been obtained from those accepted in previous scoping reports (e.g., Seagreen EIA Optimised Project Addendum 2018), while gannet nocturnal activity scores have been obtained from updated evidence from Furness et al. (2018). Herring gull and lesser black-backed gull nocturnal scores have been taken from Garthe and Hüppop (2004). It should however be noted that the level of nocturnal activity suggested by Garthe and Hüppop (2004) may be too conservative. These nocturnal activity scores will require further discussion with consultees which will be undertaken through the Ornithology Road Map process. Flight type will be set as flapping for all species as flight behaviour in the rotor swept area can be difficult to define.
517. Monthly density data for flying gannet and kittiwake will be derived from design-based methods (or MRSea outputs if this model is capable of analysing the large datasets involved without causing major run-time or error issues), whereas density data for flying herring gull, lesser black-backed gull and Arctic tern will use Design-based abundance estimates (as MRSea outputs will not be generated for these three species due to low abundances). The density values to be used within collision risk modelling will be discussed and agreed further with consultees (i.e., use of mean monthly or monthly max values).
518. Initial CRM will model a range of turbine scenarios, including realistic worst case and most likely scenario for each species. This will be informed by the Project Design Envelope. Outputs from initial CRM will inform future discussions on the worst case scenario CRM for each of the key species. These discussions will be undertaken as part of the Ornithology Road Map process.
519. To assess potential collision mortality for migratory non-seabird species, the Marine Scotland commissioned strategic level report (Marine Scotland, 2014) will be used. Species likely to migrate across the offshore ornithology study area will be identified. The report mentions that an avoidance rate of 98% is to be assumed for all species apart from an avoidance rate of 99.8% to be assumed for all geese. Collision risk modelling will be undertaken using Band Option 1 and estimates will be presented for the spring and autumn passage respectively.
520. Currently, an MS commissioned strategic report containing information on the development of the sCRM tool and the risk of collision to migratory species is awaited and will be used in future assessments if available within the EIA timescale.

 

Table 6.15: Species Parameters to be Used in the Collision Risk Modelling

 

Apportioning

521. For the assessment of impacts on different breeding colonies and in different seasons, particularly in relation to SPA breeding colonies, it is necessary to apportion the entire potential impact described for the development (e.g., the additional mortality as a result of collision risk, and/or displacement) between breeding colonies and across age-classes and seasons.
522. In the breeding season age class apportioning will be based on stable age population models, with impacts being assigned between adults and immatures using proportions derived from site specific survey data. For auk species and kittiwake, age classes will follow methods used and approved for the Seagreen 2018 assessment.
523. Impacts to all adults will be regarded as breeding adults. However, this would be a precautionary approach and it is proposed that sabbatical birds are accounted for during the assessment.
524. Apportioning during the non-breeding season will follow the BDMPS approach (Furness, 2015). For seasons defined with half months, the estimated collision mortality for that month will be split equally between the phenological periods, with seasonal definitions for each species following NS definitions (NatureScot, 2020).
525. For species such as guillemot and razorbill however, further discussion on non-breeding apportioning is required as auk species are known to disperse less widely from the breeding area during the non-breeding season. Woodward et al. (2019) mean-maximum foraging ranges for guillemot will be utilised to establish the appropriate non-breeding populations, with further discussion and agreement on razorbill non-breeding season apportioning needed. This will be undertaken as part of the Ornithology Road Map process.

Population Viability Analysis

526. The Natural England Population Viability Analysis (PVA) tool (Searle et al. 2019) will be used to model the effects of collision and displacement mortality on populations of key species from relevant SPA breeding colonies. The PVA will focus on birds where the assessed mortality exceeds a change to adult annual survival rates of 0.2% over both a 35 year and 50 year period. This will require further discussion with consultees because the 0.2% change in adult mortality may not be appropriate for all species because of interspecific variation in annual survival. This will be undertaken as part of the Ornithology Road Map process.
527. No recovery period will be applied and impacts will be applied to all ages in agreement with the age apportioning approach, with sabbatical rates of adult birds also being taken into account. The two-ratio metrics, which are generally termed ‘Counterfactual (ratio) of final population size” and “Counterfactual (ratio) of population growth-rate” will be presented.
528. In situations where there is a reasonable amount of species abundance data available, semi-integrated Bayesian population models will be considered in place of the NE PVA (Searle et al., 2020), where it is possible to run these models. These semi-integrated models tend to perform better due to the integration of abundance data.
529. The PVA input parameters (e.g., demographic species productivity and age-class survival rates) will follow the recommendations of Searle et al. (2020), with productivity and survival rates taken from Horswill and Robinson (2015). Consideration however will be given to these demographic parameters as rates suggested for certain species in Horswill and Robinson (2015) may no longer be appropriate. Clarification on the appropriate productivity and survival rates for use in the PVA for each of the key colonies will be required.

 

Ecosystem Approach

530. An ecosystems approach will be applied using the outputs of the analysis of ornithology data, taking into account broad and local scale connections between birds and the ecosystem and responses to change. The Ornithological Road Map provides a framework for engagement with consultees regarding the scope of the ecosystem approach to be taken. The road map will also need to consider the engagement required with a broad group of stakeholders for input to the ecosystem approach.
531. There are a range of tools (https://ecosystemsknowledge.net/tool-assessor-list-of-tools) available to assist with delivering the ecosystems approach and these will be discussed to determine whether they are fit for this purpose at meetings scheduled in the road map. However, the ecosystem approach assessment will draw on the outputs of the deliverables assessing collision risk, displacement, apportioning to SPAs and population viability. As a minimum, the assessment will consider marginal changes that recognise the changes to services between the baseline state and the “post-intervention” state, qualifying “likelihood of impact” for all the identified ecosystem services.

Potential Cumulative Effects

532. The Cumulative Effects Assessment (CEA) for birds will follow the approach set out in section 4.3.7. The identification of cumulative effects on birds will follow a receptor-specific approach to determine receptor-impact pathways from the cumulative screening matrix. The offshore and intertidal ornithology cumulative assessment will also take into account the principles set out in COWRIE guidance (King et al., 2009). Where necessary, effects related to operational collision and displacement will be summed across cumulative developments and subject to population assessment at relevant breeding colonies.
533. The cumulative effects assessment will focus on the cumulative effects with Seagreen 1, Neart Na Goaithe and Inch Cape. Additional projects located in Scottish and English waters will be scoped into the cumulative assessment for breeding birds based on the mean-maximum foraging ranges from Woodward et al. (2019). The non-breeding season cumulative assessment, for species that migrate or disperse from their colonies, will include relevant developments within the BDMPS region (Furness, 2015). However, for guillemot that do not disperse, the population will also be based on mean-maximum foraging range from the Proposed Development.
534. When considering the predicted collision and displacement impacts from other developments, the most recent assessments will be used as presented in the Design Specification and Layout Plans (DSLP), rather than designs for the original consented wind farms. The exception being for Inch Cape where there is no DSLP and the cumulative effects from the Section 36 application will be considered based on the revised design envelope. If suitable, collision risk modelling is available from the other relevant projects, e.g. Seagreen 2018, the results from this existing modelling will be used. If it is determined that the modelling is not suitable then new modelling will be undertaken.
535. Additional discussion will be required regarding the approach for including developments in England in the CEA. These discussions will be undertaken as part of the Ornithology Road Map process.

Potential Transboundary Impacts

536. A screening of transboundary impacts has been carried out and is presented in Appendix 3  Open .

6.4.8.    Scoping Questions

• Do you agree that the existing data available to describe the offshore and intertidal ornithology is sufficient to describe the environment in relation to the Proposed Development?
• Do you agree that all receptors and impacts have been identified for offshore and intertidal ornithology?
• Do you agree with the suggested designed in measures and is this mitigation appropriate?
• Do you agree with the proposed approach to assessment?
• Do you agree with the proposal to scope out pollution impacts during all phases of the Proposed Development?
• Do you agree with the sites screened into the MPA Assessment (as presented in Appendix 17  Open )?

6.4.9.    Next Steps

537. Undertaking an EIAR is an iterative process and not all issues relating to the ornithological impact assessment have been agreed. Further discussion is required throughout the preparation of the EIAR. Furthermore, new information or new guidance may become available that require adjustments in the approaches to impact assessment.
538. The over-arching next steps are outlined in section 4.3.4. As part of the Ornithological Road Map process any on-going uncertainties and approaches to be used in the assessment will be discussed. Results from the aerial surveys and, when ready, the initial outputs from the collision risk modelling, displacement modelling and population viability analysis will be presented