Changes in fish and shellfish communities affecting prey availability
1187 As outlined in paragraph 1051 et seq., there is potential for changes to prey availability for grey seals due to potential impacts on prey species during operation and maintenance of the Proposed Development. These impacts include temporary subtidal habitat loss/disturbance, long-term subtidal habitat loss, increased SSC and associated sediment deposition, EMF from subsea electrical cabling and colonisation of foundations, scour protection and cable protection.
1188 Potential temporary habitat loss/disturbance during operation and maintenance equates to a smaller area than that affected during construction (up to 989,000 m2 which equates to 0.08% of the fish and shellfish ecology area, compared with 9.7% during the construction phase; volume 2, chapter 9 of the Offshore EIA Report). Operation and maintenance activities will occur periodically over the full lifetime of the project (estimated to be 35 years). As described in paragraph 1167, only a small proportion of the maximum footprint of habitat loss/disturbance may occur at any one time, with areas starting to recover immediately after cessation of maintenance activities. It is expected that grey seal could come back to forage within areas previously disturbed after cessation of works and therefore their distribution and connectivity with important habitats within and outside the site is unlikely to be impaired in long term.
1189 In terms of indirect impacts associated with underwater noise and prey resources, it is anticipated that there will be no additional displacement of grey seal, as they would already be potentially disturbed from the same or larger area as a result of underwater noise during maintenance activities.
1190 Increased SSC could occur as a result of repair or remedial burial activities during the operation and maintenance phase. The maintenance activities will be undertaken at intervals over the 35 years operation and maintenance phase. The assessment presented in volume 2, chapter 9 of the Offshore EIA Report considered that any suspended sediments and associated deposition will be of the same magnitude, or lower as for construction, with the sensitivity of the receptors similar to that assessed for the construction phase. The availability of suitable food supply for grey seals is not expected to be impaired as a result of increase in suspended sediments and associated deposition.
1191 The presence and operation of inter-array, interconnector and offshore export cables will result in emissions of localised electrical and magnetic fields, which could potentially affect the sensory mechanisms of some species of fish and shellfish. The range over which species can detect EMF will be very localised to within a few centimetres of the buried cable, with rapid decay of the EMF with increasing distance. Considering the above, adverse effects on grey seal as a result of changes in fish and shellfish communities affecting prey availability due to EMF are highly unlikely.
1192 Although there will be long term loss of habitat due to the presence of infrastructure associated with the Proposed Development, it is also anticipated that artificial structures will provide hard settlement opportunities and provide a valuable food source for fish. As discussed in paragraph 1021 et seq, evidence increasingly suggests that foraging opportunities for marine mammals, including grey seals, are increased around offshore wind farm structures.
1193 As outlined in paragraph 1023 et seq., while grey seal has a relatively selective diet of predominantly flatfish and sandeel, the species has an observed wide ranging foraging ability within the region. The fish and shellfish communities found within the fish and shellfish ecology study area (see volume 2, chapter 9 of the Offshore EIA Report) are characteristic of the fish and shellfish assemblages in the northern North Sea. The impacts of operation and maintenance works will be highly localised, temporary in nature and restricted to the boundaries of the Proposed Development, only a small area will ever be affected compared with the available foraging habitat for grey seals in the northern North Sea. It is therefore reasonable to assume that, due to the highly mobile nature of grey seals, there will be similar and suitable prey resources available in the wider area. Given that the habitat is likely to return to the state that existed before the activity or event which caused change, it is highly unlikely that maintenance works resulting in habitat loss/disturbance will influence grey seal population trajectory in the long-term.
1194 Significant adverse effects on the qualifying Annex II marine mammal feature grey seal of the Berwickshire and North Northumberland Coast SAC are not predicted to occur as a result of changes in fish and shellfish communities affecting prey availability during the operation and maintenance phase (i.e. in relation to maintaining the cover and abundance of preferred food items required by the species).
Conclusion
1195 The assessment has concluded that grey seal distribution and connectivity with important habitats within and outside the site as well as the availability of suitable food supply is unlikely to be impaired in long term. Therefore there is no risk of structure and function of the habitats of qualifying species being affected. It is expected that grey seal population would be able to tolerate the effect of changes in fish and shellfish communities without any impact on reproduction and survival rates and the population of qualifying species will not be affected. As such, the conservation objectives for Annex II species, grey seal, will not be undermined.
1196 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC from changes in fish and shellfish communities affecting prey availability with respect to the operation of the Proposed Development acting alone.
Effects in-combination
1197 An assessment of in-combination effects upon the qualifying Annex II marine mammal species of the Berwickshire and North Northumberland Coast SAC arising from each identified impact is provided below.
1198 The potential to experience injury in terms of PTS by marine mammal receptors as a result of underwater noise due to piling and vessel use/other activities would be expected to be largely localised within the boundaries of the respective projects (assuming similar ranges of effect as presented for the Proposed Development). It is also anticipated that standard offshore wind industry construction methods (which include soft starts and visual and acoustic monitoring of marine mammals as standard) will be applied, thereby reducing the magnitude of the impact with respect to auditory injury occurring in marine mammals. Therefore, there is no potential for significant in-combination impacts for injury from elevated underwater noise during pilling and vessel use/other activities and the in-combination assessment focuses on disturbance only.
Assessment of in-combination effects during construction and decommissioning
Injury and disturbance from elevated underwater noise during piling
Tier 2
1199 The construction of the Proposed Development, together with the construction of the following Tier 2 projects, may lead to injury and/or disturbance to grey seal from the Berwickshire and North Northumberland Coast SAC from underwater noise during piling:
- Tier 2:
– Inch Cape Offshore Wind Farm; and
– Seagreen 1A Project.
1200 Both projects screened in for the in-combination assessment for grey seal are located within a behavioural disturbance footprint of the Proposed Development. The outermost contour of 135 dB represents the edge of the area within which grey seal may experience behavioural disturbance during concurrent piling at 4,000 kJ hammer energy at the Proposed Development. The assessment presented in the Inch Cape EIA (Inch Cape Offshore Limited, 2018) and original Seagreen EIA (Seagreen Wind Energy Ltd, 2012) estimated that 1,236 and 465 grey seals could experience disturbance during piling at respective projects. The duration of any disturbance at Seagreen 1A Project will be relatively short and is currently planned to take place between April and July 2023, which is more than two years before planned commencement of piling at the Proposed Development (Seagreen Wind Energy Ltd, 2020).
1201 The construction of Inch Cape and Seagreen 1A Project will be completed prior to commencement of piling at the Proposed Development so the potential for simultaneous piling, and therefore additive in-combination effects, with Proposed Development is highly unlikely. Nevertheless, population modelling was carried out to explore the potential of cumulative effects as a result of disturbance during piling to affect the population trajectory over time. Population modelling considered Seagreen 1A Project and Inch Cape Offshore Wind Farm and respective numbers of animals potentially impacted against the wider MU population (see volume 3, appendix 10.4 for methods applied in the model). Results of the cumulative iPCoD modelling for grey seal showed that no impacts are predicted on the wider MU population resulting from disturbance due to cumulative piling events, with the mean impacted population the same as the mean unimpacted population at the 25 year time point. Therefore, it was considered that there is no potential for a long-term effects on this species within wider population as a result of cumulative piling at proposed Development and respective projects (see volume 3, appendix 10.4 for more details).
1202 In temporal terms, there is a potential that animals in the vicinity of the Firth of Forth and Tay will experience disturbance consecutively as piling at different projects progresses. Grey seals are known to modify their behaviour in a response to piling noise but come back to pre-piling behaviour immediately after pile-driving ceased (Aarts et al., 2018). Therefore, it is anticipated that piling will not result in any long-lasting changes in the distribution of adult seals from this SAC and the connectivity with areas of high importance within and outside the site is not expected to be impaired. Given that the risk of simultaneous piling is very low and that grey seal population in Berwickshire and North Northumberland Coast SAC is increasing, it is unlikely that effect as a result of piling in-combination with other projects has the potential to have a significant impact on grey seal population trajectory in long term. Therefore, it is highly unlikely that the reproductive and recruitment capability of the species will be affected.
1203 As described in paragraph 1133, during piling at Proposed Development, the outer behavioural disturbance contours (135 dB) overlap with coastal areas south of the Proposed Development and therefore there is a small overlap with northern part of the Berwickshire and North Northumberland Coast SAC (in volume 2, chapter 10 of the Offshore EIA Report, Figure 13.1 Open ▸ ). As there will be no temporal overlap of piling phases with either of the projects, and since both projects are located further from the Berwickshire and North Northumberland Coast SAC, grey seals present in vicinity of habitats utilised throughout their life cycle are highly unlikely to experience disturbance cumulatively. As such, as stated for the Proposed Development alone, piling activities are highly unlikely to disrupt normal behaviours of grey seals or adversely affect reproduction and survival rates.
1204 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of underwater noise during piling during construction with respect to the Proposed Development acting in-combination with Tier 2 projects.
Injury and disturbance from elevated underwater noise during site investigation surveys
Tier 2
1206 The construction as well as operation and maintenance phases of Eastern Link 1 and Eastern Link 2, located respectively 14 km and 28 km from the Proposed Development array area, will overlap with the construction phase of the Proposed Development. Based on the Environmental Appraisals for both projects, the only underwater sound noise sources that are within hearing range of marine mammals and have potential to have an effect, are the operation of the USBL and the SBP (AECOM, 2022a; 2022b). The disturbance ranges for grey seal were estimated as 63 m for USBL and 4,642 m for SBP. The detailed assessment of impacts as a result of underwater noise during the operation of SBP for both projects was presented for installation phase only. There were no disturbance ranges presented for a USBL for the Proposed Development alone but the disturbance range for SBP has been assessed as 2,045 m. Nevertheless, the assessment presented in paragraph 955 et seq. is based on the maximum disturbance range all geophysical activities, which for the Proposed Development was predicted for vibro-coring as 7,459 m. Using the published at-sea density maps (Carter et al., 2020), the maximum number of grey seals estimated to be disturbed was 210 grey seals (21% of the Berwickshire and North Northumberland Coast SAC population). However, this was shown to be highly precautionary when compared with estimates of the number of grey seal using site-specific densities derived from the Proposed Development aerial digital survey data (see paragraph 1142 for more details).
1207 Based on the distance from the Proposed Development to both projects, the overlap of disturbance ranges is highly unlikely. The potential for an overlap exist only for site-investigation surveys taking place in the northern part of the Eastern Link 1, close to the Proposed Development export cable corridor and landfall ( Figure 13.3 Open ▸ , the Berwickshire and North Northumberland Coast SAC is 0.1 km from the Eastern Link 1 marine installation corridor). However, it must be noted that site investigation survey equipment will not be operating continuously, it will be used when required for investigations of particular areas of the seabed where additional information is required to inform the construction.
1208 With foraging ranges of up to 100 km, grey seals may be sensitive to behavioural disturbance during the site-investigation surveys as they move between haul-outs and key foraging areas. As advised by NatureScot ( Table 8.1 Open ▸ ), grey seal in Scotland tend to stay within 20 km of the breeding colony during the breeding season, therefore that further restricts the foraging grounds in the vicinity of haul outs. During the breeding or moulting season many seals tend to spend more time on land, unaffected by underwater sound. Nevertheless, the availability of food is vital to offspring survival and female fitness (see paragraph 1085 et seq. for more details). Animals may be deterred from foraging grounds during the operation of the survey equipment. However, given that alternative areas for foraging are widely available, the disturbance to seals foraging offshore is not considered likely to have a significant impact on food availability (see paragraph 1225 et seq. for the in-combination assessment of impacts as a result of changes in fish and shellfish communities affecting prey availability) and therefore on fitness and survival of the grey seal population. Given that geophysical surveys will occur intermittently and are short in duration, grey seals are anticipated to return to foraging grounds when the impact has ceased and therefore the connectivity with important habitats within and outside the site is unlikely to be impaired.
1209 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of site investigation surveys during the construction phase with respect to the Proposed Development acting in-combination with Tier 2 projects.
Injury and disturbance from elevated underwater noise during UXO clearance
Tier 2
1210 There is potential for in-combination effects from injury and/or disturbance from underwater noise during UXO clearance to grey seal from the Berwickshire and North Northumberland Coast SAC during the construction phase of the Proposed Development with activities associated with Inch Cape Offshore Wind Farm and Moray West Offshore Wind Farm.
1211 Projects screened in for this in-combination assessment are expected to involve similar construction activities to those described for the Proposed Development alone, including UXO clearance works. It is anticipated that, for all projects, impacts associated with these activities will require additional assessment under EPS licensing, however such applications are not yet available in the public domain.
1212 For the Proposed Development alone, the maximum range across which grey seals have the potential to experience PTS due to high order detonation of 300 kg charge was assessed as approximately 2,085 m. PTS onset ranges for Inch Cape Offshore Wind Farm and Moray West are currently unknown but for the purpose of this assessment, we can assume that the maximum adverse scenario is not greater than assessed for the Proposed Development alone. Depending on the type of detonation and size of the explosive, UXO clearance activities may have residual effects in respect to marine mammals and PTS injury. In November 2021, the UK government published a joint interim statement advising to use low noise alternatives to high order detonations where possible and it is anticipated that future developments will follow this guidance. However, due to a small inherent risk with these clearance methods that the UXO will detonate or deflagrate violently, accidental high order detonation can be expected as a maximum adverse scenario. Taking into account high order detonation of 300 kg charge and appropriate designed-in and secondary mitigation measures (paragraph 967 et seq.), there will be no residual risk of injury and therefore, it is highly unlikely that the reproductive and recruitment capability of the species will be impacted.
1213 In terms of TTS, for the Proposed Development alone, the range across which grey seals have the potential to experience TTS due to high order detonation of a 300 kg charge was as approximately 6,430 m. TTS onset ranges for Inch Cape Offshore Wind Farm and Moray West Offshore Wind Farm are currently unknown, but for the purpose of this assessment we can assume that the maximum adverse scenario is no greater than assessed for the Proposed Development alone. A spatial maximum adverse scenario would occur where UXO clearance activities occur concurrently at the respective projects considered in the in-combination assessment. This is however highly unlikely, as due to safety reasons the UXO clearance activities takes place before other construction activities commence, and both projects considered in the CEA start their construction activities two years before commencement of construction at Proposed Development. Temporally however, sequential UXO clearance at respective projects could lead to a longer duration of effect. Since each clearance event results in no more than a one second ensonification event and since TTS is a recoverable injury, the potential for in-combination effects with respect to TTS is considered to be very limited. Therefore, in-combination effects caused by UXO clearance are considered unlikely to cause a change in reproduction and survival rates or alteration in the distribution of the population from Berwickshire and North Northumberland Coast SAC. Given that effect of TTS is short in duration, connectivity with important habitats within and outside the site is also unlikely to be impaired.
1214 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of underwater noise during UXO clearance during the construction phase with respect to the Proposed Development acting in-combination with Tier 2 projects.
Injury and disturbance from elevated underwater noise during vessel use and other activities
Tier 2
1215 There is potential for in-combination effects from injury and/or disturbance from underwater noise due to vessel use and other activities to grey seal from the Berwickshire and North Northumberland Coast SAC during the construction and decommissioning phase of the Proposed Development with activities associated with the following projects: Eyemouth disposal site, Inch Cape Offshore Wind Farm, Seagreen 1, Seagreen 1A Project, Eastern Link 1, Eastern Link 2, Neart na Gaoithe and Blyth Demo 2.
1216 Whilst there is no quantitative information available for noise disturbance ranges for offshore wind farms included in this CEA, it is anticipated that there will be a similar scale of effects with respect to noise effects as those described for Proposed Development alone (paragraph 988 et seq.). In terms of behavioural disturbance, the noise modelling predicted a maximum range of approximately 4 km for construction activities such as cable laying as well as activity of rock placement vessels (described in detail in volume 3, appendix 10.1 of the Offshore EIA Report) and therefore, there is a potential for disturbance effects to occur cumulatively. Given that construction activities for the other offshore wind projects have commenced in 2020 and that this is an area of relatively high vessel traffic (see paragraph 989 et seq. for more details), it can be anticipated that grey seals from the Berwickshire and North Northumberland Coast SAC demonstrate some degree of habituation to ship noise. Therefore, in-combination effects caused by vessel use and other activities are considered unlikely to cause a change in reproduction and survival rates or alteration in the distribution of the population from Berwickshire and North Northumberland Coast SAC.
1217 The highest number of vessels movements was predicted during the construction phase of each offshore wind farm. There would potentially be a relatively small temporal overlap of the construction phases, with only one year of overlap with Inch Cape as well as Seagreen 1A Project and the Proposed Development. Therefore, the potential in-combination effect during construction phases of the respective projects and the proposed Development will be short-term (no more than one year).
1218 Vessel movements will be confined to the array areas and/or Proposed Development export cable corridor routes and will follow existing shipping routes to/from port. In Scotland, grey seal are thought to primarily forage within 20 km of the breeding colony during the breeding season. Given the location of respective projects screened into in-combination assessment, there is unlikely to be overlap with the zones of impact of in-combination projects with the southern part of the SAC, which is an important haul out area for grey seals (paragraph 1120). Given that the disturbance will be largely localised to boundaries of respective projects and cumulatively could affect grey seals over short term, it is highly unlikely that vessel use will influence grey seal SAC population trajectory in the long-term.
1219 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of underwater noise during vessel use and other activities during the construction phase with respect to the Proposed Development acting in-combination with Tier 2 projects.
Tier 3
1222 Due to lack of project information at this stage, it is not possible to undertake full, quantitative assessment for this impact and therefore a qualitative assessment is provided. The maximum range over which potential disturbance may occur for the Proposed Development alone as a result of drilled piling and jet trenching, is predicted out to 1,900 m and 2,580 m, respectively. Cable installation activities assessed for the Proposed Development alone have the potential to disturb marine mammals out to 4,389 m. Given the location of the SAC with respect to the Proposed Development and Cambois connection, there is no potential for cumulative overlap of behavioural ZoI at respective projects and this designated site.
1223 Nevertheless, outside the SAC in offshore waters, construction activities could lead to a larger area of disturbance and larger number of animals disturbed within their foraging range compared to the Proposed Development alone if projects were to conduct construction activities over similar time periods. As described in paragraph 1216 et seq., it can be anticipated that grey seals from this SAC demonstrate some degree of habituation to ship noises. Therefore, in-combination effects caused by vessel use and other activities are considered unlikely to cause a change in reproduction and survival rates or long-term alteration in the distribution of the population from Berwickshire and North Northumberland Coast SAC.
1224 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of underwater noise during vessel use and other activities during the construction phase with respect to the Proposed Development acting in-combination with Tier 3 projects.
Changes in fish and shellfish communities affecting prey availability
Tier 2
1226 The construction phases and/or operation and maintenance phases of projects screened into in-combination assessment may lead to in-combination temporary subtidal habitat loss/disturbance. The total in-combination temporary subtidal habitat loss is 145,325,450 m2 (=145.3 km2), however this number is highly conservative as the temporal overlap in construction activities between projects will be small and therefore there will only be a small area of temporary habitat loss happening at any one time. The magnitude of long-term habitat loss caused by the presence of all structures on the seabed has been considered for the construction as well as operation and maintenance phases. The impacts have been assessed in-combination with Inch Cape Offshore Wind Farm, Neart na Gaoithe Offshore Wind Farm, and Seagreen 1, Seagreen 1A Project and Seagreen 1A Export Cable Corridor, Eastern Link 1 and Eastern Links 2 and may lead to long term subtidal habitat loss of up to 15,014,156 m2 (=15.0 km2).
1228 As outlined in paragraph 1023 et seq., while grey seal has a relatively selective diet of predominantly flatfish and sandeel, the species can forage widely, sometimes covering extensive distances. Given that the impacts of temporary and long-term habitat loss/disturbance will be localised when compared to wider habitat available and largely restricted to the boundaries of the respective projects, only a small area will be affected when compared to available foraging habitat for grey seals in the northern North Sea. Based on the telemetry study, most grey seal tracks originating from Berwickshire and North Northumberland Coast SAC are confined to the south of the Proposed Development array area and Proposed Development export cable corridor ( Figure 13.1 Open ▸ ). All projects listed in paragraph 1225, except Eastern Link 1 and Easter Link 2, are located north from the Proposed Development array area and therefore do not overlap with areas characterised by high density of grey seal telemetry tracks. As such, it can be assumed that the majority of the area affected by temporary habitat disturbance/habitat loss at projects considered in in-combination assessment ( Figure 13.3 Open ▸ ) does not represent important foraging grounds for individuals from Berwickshire and North Northumberland Coast SAC. Additionally, since the habitat is likely to return to the state that existed before the activity or event which caused change, the availability of suitable food supply for grey seals is not expected to be impaired hence the population trajectory is unlikely to be affected in the long-term.
1229 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of changes in fish and shellfish communities affecting prey availability during construction and decommissioning with respect to the Proposed Development acting in-combination with Tier 2 projects.
Tier 3
1230 There is potential for in-combination effects from changes in fish and shellfish communities affecting prey availability to grey seal from Berwickshire and North Northumberland Coast SAC during the construction and decommissioning phases of the Proposed Development with activities associated with the construction and operation of Cambois connection.
1231 The construction phase of Cambois connection may lead to in-combination temporary subtidal habitat loss/disturbance. The total in-combination temporary subtidal habitat loss/disturbance is 17,000,000 m2 (=17.0 km2), however this number is highly conservative as the temporal overlap in construction activities between projects will be small and therefore there will only be a small area of temporary habitat loss happening at any one time. The majority of this disturbance will not spatially overlap with the Proposed Development and where the overlap exist with the Proposed Development array area (previously impacted during the construction of the Proposed Development), it is expected to be highly localised and so the potential for repeat disturbance is considered low and unlikely to lead to an increase in the magnitude than predicted for the Proposed Development alone. The installation of Cambois connection can also result in a total area of long-term subtidal habitat loss of 306,000 m2.
1232 There is also a potential for in-combination effects associated with SSC and associated deposition. However, elevations in SSC during the construction phase will be of short duration, returning to background levels relatively quickly. SSC will not reach the concentrations required for an extended period for there to be any effect on fish and shellfish adult/larvae survival. Therefore, it is highly unlikely to have indirect impacts on grey seals from Berwickshire and North Northumberland Coast SAC via changes to prey species.
1233 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of changes in fish and shellfish communities affecting prey availability during construction and decommissioning with respect to the Proposed Development acting in-combination with Tier 3 projects.
Figure 13.3: Adult Grey Seal Telemetry Tracks Overlaid with Projects Considered in In-Combination Assessment (Except Moray West Due to Scale)
Assessment of in-combination effects during operation and maintenance
Injury and disturbance from elevated underwater noise during site investigation surveys
Tier 2
1234 There is potential for in-combination effects from injury and/or disturbance from underwater noise due to site investigation surveys to grey seal from the Berwickshire and North Northumberland Coast SAC during the operation and maintenance phase of the Proposed Development with the operation and maintenance Eastern Link 1 and Eastern Link 2.
1235 The maximum design scenario for Proposed Development alone comprises of routine geophysical surveys estimated to occur every six months for first two years and annually thereafter. This equates to up to 37 surveys over the 35-year life cycle of Proposed Development ( Table 11.2 Open ▸ ). As presented in paragraph 1206, the detailed assessment of impacts on marine mammals as a result of underwater noise due to geophysical surveys during the operation and maintenance phase of the Eastern Link 1 and Eastern Link 2 is unavailable.
1236 An overview of potential impacts from as a result of behavioural disturbance due to elevated underwater noise during geophysical site investigation surveys is described in paragraph 1205 et seq. for the construction phase and has not been reiterated here for the operation and maintenance phase. The magnitude of the impact of underwater noise from geophysical surveys during operation and maintenance phase in combination with other projects considered in cumulative assessment could result in a negligible alteration to the distribution of grey seal in the short-term, however the overlap of disturbance ranges is unlikely. Given that geophysical surveys will occur intermittently over operation and maintenance phases of respective projects and are short in duration, grey seals are anticipated to return to foraging grounds when the impact has ceased and therefore the connectivity with important habitats within and outside the site is unlikely to be impaired.
1237 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of site investigation surveys during the operation and maintenance phase with respect to the Proposed Development acting in-combination with Tier 2 projects.
Injury and disturbance from elevated underwater noise during vessel use and other activities
Tier 2
1239 Vessels involved in the operation and maintenance of other wind farms will include a similar suite of vessels as those described for the Proposed Development alone (see paragraph 989 et seq.), such as vessels used during routine inspections, repairs and replacement of equipment, major component replacement, painting or other coatings, removal of marine growth and replacement of access ladders. It has been assumed that future case traffic growth is likely to fluctuate depending on seasonality and cargo and industry trends. Based on the telemetry data, only few grey seals individuals from Berwickshire and North Northumberland Coast SAC may range further than 100 km radius from haul out sites (including juveniles), therefore projects located further offshore are unlikely to have in-combination effects on this SAC ( Figure 13.3 Open ▸ ).
1240 Given that the number of vessel round trips and their frequency is much lower for the operation and maintenance phases compared to construction phases of the respective projects, the magnitude of the impact for disturbance as a result of elevated underwater noise due to vessel use and other activities is expected to be less than that assessed for the construction phase. However, the duration of the effect will be longer (over the 35-year operating lifetime of the Proposed Development).
1241 During the operation and maintenance phase of the Proposed Development, the wind farms listed in paragraph 1238 will reach their decommissioning age before the Proposed Development reaches its decommissioning age in 2066. The environmental statements for respective projects predicted the number and type of vessels associated with decommissioning are expected to be, at worst, similar to construction. Therefore, in-combination effects caused by vessel use and other activities during operation and maintenance phase are considered unlikely to cause a change in reproduction and survival rates or alteration in the distribution of the population from Berwickshire and North Northumberland Coast SAC.
1242 Additionally, it can be expected that after more than ten years of construction activities taking place in the vicinity of Firth of Forth (i.e. Seagreen 1 construction activities commenced in 2021 and the operation and maintenance phase of Proposed Development is expected to start from 2033), marine mammals present in the area will demonstrate some degree of habituation to ship noises.
1243 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of underwater noise during vessel use and other activities during the operation and maintenance phase with respect to the Proposed Development acting in-combination with Tier 2 projects.
Tier 3
1244 There is potential for in-combination effects from underwater noise due to vessel use and other activities to grey seal from Berwickshire and North Northumberland Coast SAC during the operation and maintenance of the Proposed Development with activities associated with the operation of Cambois connection.
1245 As presented in paragraph 1221, there were no details about the number of vessel round trips or type of vessels that will be used during operation and maintenance phase of Cambois connection (SSE Renewables, 2022e). Due to lack of detailed project information at this stage, it was not possible to undertake full, quantitative assessment for this impact.
1246 An overview of potential impacts for behavioural disturbance to grey seal from Berwickshire and North Northumberland Coast SAC from elevated underwater noise due to vessel use and other activities is described in paragraph 1220 et seq. for the construction phase and have not been reiterated here for the operation and maintenance phase.
1247 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of underwater noise during vessel use and other activities during the operation and maintenance phase with respect to the Proposed Development acting in-combination with Tier 3 projects.
Changes in fish and shellfish communities affecting prey availability
Tier 2
1248 There is potential for in-combination effects from changes in prey resources to grey seal from the Berwickshire and North Northumberland Coast SAC during the operation and maintenance phase of the Proposed Development with activities associated with the following projects: Inch Cape Offshore Wind Farm, Neart na Gaoithe Offshore Wind Farm, Seagreen 1, Seagreen 1A Project, Seagreen 1A Export Cable, Eastern Link 1, Eastern Link 2, and Eyemouth disposal site.
1249 Operation and maintenance activities at respective projects considered in in-combination assessment may lead to temporary subtidal habitat loss/disturbance of up to 32,276,397 m2. Additionally, Offshore Wind Farms listed above will reach their decommissioning age during Proposed Development operation and maintenance phase. It is important to note that the maximum design scenario for habitat loss from the respective projects is precautionary, as operation and maintenance activities will occur intermittently throughout the lifetime of the Proposed Development and the temporal overlap with activities at other projects is unlikely. As described in paragraph 1167, only a small proportion of the maximum footprint of habitat loss/disturbance may be affected at any one time, areas will start to recover immediately after cessation of maintenance activities. It is expected that grey seal could come back to forage within areas previously disturbed after cessation of works and therefore their distribution and connectivity with important habitats within and outside the site is unlikely to be impaired in long term.
1250 In-combination impacts could arise from EMFs due to the presence of subsea cabling during the operation and maintenance phases of the Proposed Development as well as Inch Cape Offshore Wind Farm, Neart na Gaoithe Offshore Wind Farm, Seagreen 1, Seagreen 1A Project, Seagreen 1A Export Cable, Eastern Link 1 and Eastern Link 2. A total length of up to 6,112 km of subsea cabling was estimated for all projects. The EMF was predicted to be of local spatial extent Considering the above, adverse effects on grey seal as a result of changes in fish and shellfish communities affecting prey availability due to EMF are unlikely.
1251 As outlined in paragraph 1023 et seq., while grey seal has a relatively selective diet of predominantly flatfish and sandeel, the species can forage widely, sometimes covering extensive distances. Given that the impacts of temporary and long-term will be localised when compared to wider habitat available and largely restricted to the boundaries of the respective projects, only a small area will be affected when compared to available foraging habitat for grey seals in the northern North Sea. Based on the telemetry study, most grey seal tracks originating from Berwickshire and North Northumberland Coast SAC are confined to the south of the Proposed Development array area and Proposed Development export cable corridor ( Figure 13.1 Open ▸ ). Therefore, it can be assumed that the area affected by temporary habitat disturbance/habitat loss at projects considered in in-combination assessment does not represent important foraging grounds ( Figure 13.3 Open ▸ ). Additionally, since the habitat is likely to return to the state that existed before the activity or event which caused change, the availability of suitable food supply for grey seals is not expected to be impaired hence the population trajectory is unlikely to be affected in the long-term.
1252 Artificial structures introduced into areas of predominantly soft sediments has the potential to alter community composition and biodiversity. There is a potential for in-combination effects arising from colonisation due to the presence of Inch Cape Offshore Wind Farm, Neart na Gaoithe Offshore Wind Farm, Seagreen 1, Seagreen 1A Project, Seagreen 1A Export Cable Corridor, Eastern Link 1 and Eastern Link 2 with a maximum scenario of up to 15,014,156 m2 of hard structures from wind turbines, OSP/Offshore convertor station platforms, meteorological masts, of cable protection, and cable crossings. The in-combination effect was predicted to be of local spatial extent. There is some evidence that marine mammal populations are likely to benefit from introduction of hard substrates and associated fauna, as studies reported that grey seal were frequently recorded around offshore oil and gas structures (see paragraph 1022 for more details). Therefore, it likely that placement of man-made structures on the seabed will benefit grey seal population.
1253 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of changes in fish and shellfish communities affecting prey availability during operation and maintenance with respect to the Proposed Development acting in-combination with Tier 2 projects.
Tier 3
1254 There is potential for in-combination effects from changes in fish and shellfish communities affecting prey availability to grey seal from Berwickshire and North Northumberland Coast SAC during the operation and maintenance phase of the Proposed Development with activities associated with the operation of Cambois connection.
1255 In terms of temporary subtidal habitat loss/disturbance, there are no specific values for the operation and maintenance phase of Cambois connection which will occur during the operation and maintenance phase of the Proposed Development. However, Cambois connection has the potential to result in cumulative EMF effects from subsea electrical cabling within the Proposed Development. The Cambois connection is understood to have 680 km of cable. The effect of EMF was predicted to be of local spatial extent.
1256 The Cambois connection has the potential to create 306,000 m2 of new hard habitat associated with rock/mattress cable protection, which represents a change in seabed type, the effects of which are described in paragraph 1022 et seq. As the cable protection does not extend into the water column the opportunity for colonisation by some species is reduced, nevertheless there is a potential that placement of man-made structures on the seabed will benefit grey seal population.
1257 Therefore, it can be concluded that there is no risk of an Adverse Effect on Integrity on the Berwickshire and North Northumberland Coast SAC as a result of changes in fish and shellfish communities affecting prey availability during operation and maintenance with respect to the Proposed Development acting in-combination with Tier 3 projects.