15.4 Integrity Matrices for Site Designated for Annex II Marine Mammals

Table 15.8: Integrity Matrix for Annex II Marine Mammal Species of the Berwickshire and North Northumberland Coast SAC

× - no Adverse Effect on Integrity

 - Potential Adverse Effects on Integrity

a: Injury and disturbance from elevated underwater noise during piling –  The maximum range for injury to grey seal as a result of underwater noise due to piling was estimated as 118 m. However, with application of designed-in measures, including visual and acoustic monitoring as well as secondary measures (the use of ADD), risk of injury to grey seal will be reduced to negligible. In terms of behavioural disturbance, a maximum of 532 animals from Berwickshire and North Northumberland SAC could potentially experience mild disturbance or barrier effects within the foraging range from the SAC. However, there will be no overlap of noise disturbance contours with important breeding areas within this SAC (Farne Islands) and therefore piling activities are highly unlikely to disrupt normal behaviours of grey seals or negatively affect maintenance of the supporting habitats within the site. During piling, there is the potential for some animals to be temporarily deterred from the offshore areas. Grey seals although initially displaced due to pile-driving, are likely to return to the same area on subsequent trips following cessation of piling and 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. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, grey seal, during the construction phase as a result of underwater noise during piling.

b: Injury and disturbance to marine mammals from elevated underwater noise during site investigation surveys – The maximum range for injury to grey seal as a result of underwater noise during site-investigation surveys was estimated as 65 m, however, with application of designed-in measures, risk of injury to grey seal will be reduced to negligible. In terms of behavioural disturbance, the largest distance over which disturbance could occur potentially affecting grey seal is out to approximately 7.5 km during vibro-coring. The surveys will take place over a period of up to three months during the construction phase and routinely over 35 year life cycle of project. Although there is a potential for grey seal to experience behavioural disturbance during the site-investigation surveys (mainly in areas outside of the SAC), the surveys are expected to be very short in duration with animals returning to baseline levels soon after surveys have ceased. Underwater noise during site investigation surveys is unlikely to affect grey seal from Berwickshire and North Northumberland SAC at a level that would substantially affect their behaviour and cause change in reproduction and survival rates. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, grey seal, during the construction and operation phases as a result of underwater noise during site investigation surveys.

c: Injury and disturbance to marine mammals from elevated underwater noise during UXO clearance – The maximum range for injury to grey seal as a result of underwater noise due to UXO clearance was estimated as 2,085 m due to detonation of charge size of 300 kg, however, with application of designed-in as well as secondary measures (including the use of ADD), risk of injury to grey seal will be reduced to low. In terms of fleeing response, up to 156 animals were predicted at risk to experience TTS at a maximum range of 6,430 m due to detonation of charge size of 300 kg. Although high-order detonation is assessed as a maximum design scenario, low order techniques will be applied as the intended methodology for clearance of UXO. Underwater noise modelling predicted that grey seal can potentially experience TTS at the maximum range of 455 m due to detonation of 0.5 kg clearance shot following low order clearance with up to one grey seal potentially affected. TTS is a temporary hearing impairment and therefore animals are likely to fully recover from the effect. Therefore, 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 this effect is short in duration, connectivity with important habitats within and outside the site is also unlikely to be impaired. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, grey seal, during the construction phase as a result of underwater noise during UXO clearance.

d: Injury and disturbance to marine mammals from elevated underwater noise due to vessel use and other activities – The threshold for injury is not exceeded by any vessel with the exception of rock placement vessel, for which an injury range of 5 m from the source was reported. With regard to behavioural disturbance to grey seals, cable laying activities result in the greatest modelled disturbance ranges out to 4,389 m. Grey seal is likely to be sensitive to disturbance from vessel traffic, however, most of the vessel traffic associated with construction and decommissioning will take place within the Proposed Development array area and Proposed Development export cable corridor, at a distance where overlap of noise disturbance contours with the southern half of the SAC (an important breeding site) is unlikely. Construction and decommissioning activities will be carried out over a medium term. Operation and maintenance activities will occur over the full lifetime of the project (estimated to be 35 years), however, only a small proportion of vessel use and other activities will occur at any one time. Since the behavioural effect is considered to be highly reversible, it is highly unlikely that it will influence grey seal population trajectory in the long-term. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, grey seal, during the construction, operation and maintenance and decommissioning phases as a result of underwater noise due to vessel noise and other activities.

e: Changes in fish and shellfish communities affecting prey availability – Changes to the prey species may occur due to temporary and long-term habitat loss/disturbance, increased SSC and associated sediment deposition, and injury and/or disturbance from underwater noise and vibration. However, given that the impacts will be highly localised and largely restricted to the boundaries of the Proposed Development, only a small area will be affected when compared to available foraging habitat for grey seals in the northern North Sea. It is expected that grey seal population would be able to tolerate the effect without any impact on reproduction and survival rates. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, grey seal, during the construction, operation and maintenance and decommissioning phases as a result of changes in fish and shellfish communities affecting prey availability.

f: In-combination – the in-combination assessment considered the potential for underwater noise during piling, UXO clearance, site-investigation surveys, vessel use and other activities and changes in fish and shellfish communities affecting prey availability from the Proposed Development alone to interact with similar effects arising from other projects included in the Tier 2 and Tier 3 assessments. In-combination effects are not predicted to result in effects of greater significance than as assessed for the Proposed Development alone. It is therefore concluded that there is no potential for Adverse Effects on Integrity on the Annex II marine mammal qualifying interest feature of the site, grey seal, during the construction and decommissioning or operation and maintenance phases in-combination with other projects.

Table 15.9: Integrity Matrix for Annex II Marine Mammal Species of the Isle of May SAC

× - no Adverse Effect on Integrity

 - Adverse Effect on Integrity

a: Injury and disturbance from elevated underwater noise during piling –  The maximum range for injury to grey seal as a result of underwater noise due to piling was estimated as 118 m. However, with application of designed-in measures, including visual and acoustic monitoring as well as secondary measures (use of ADD), risk of injury to grey seal will be reduced to negligible. In terms of behavioural disturbance, a maximum of 18 animals from Isle of May SAC could potentially experience mild disturbance. However, the behavioural disturbance contours do not reach the coast and hence do not overlap with the Isle of May SAC. Therefore, grey seals present within the SAC are unlikely to experience disturbance and piling activities are highly unlikely to disrupt normal behaviours of grey seals or adversely affect maintaining supporting habitats within the site. During piling, there is the potential for some animals to be temporarily deterred from the offshore areas. Grey seals although initially displaced due to pile-driving, are likely to return to the same area on subsequent trips following cessation of piling and 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. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, grey seal, during the construction phase as a result of underwater noise during piling.

b: Injury and disturbance to marine mammals from elevated underwater noise during site investigation surveys – The maximum range for injury to grey seal as a result of underwater noise during site-investigation surveys was estimated as 65 m, however, with application of designed-in measures, risk of injury to grey seal will be reduced to negligible. In terms of behavioural disturbance, the largest distance over which disturbance could occur potentially affecting grey seal is out to approximately 7.5 km during vibro-coring. Due to the distance from the Isle of May SAC, the overlap of behavioural disturbance ranges with site boundaries is unlikely. The surveys will take place over a period of up to three months during the construction phase and routinely over 35 year life cycle of project. Although there is a potential for grey seal to experience behavioural disturbance during the site-investigation surveys (outside of the SAC), the surveys expected to be very short in duration with animals returning to baseline levels soon after surveys have ceased. Underwater noise during site investigation surveys is unlikely to affect grey seal from Isle of May SAC at a level that would substantially affect their behaviour and cause change in reproduction and survival rates. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, grey seal, during the construction and operation phases as a result of underwater noise during site investigation surveys.

c: Injury and disturbance to marine mammals from elevated underwater noise during UXO clearance – The maximum range for injury to grey seal as a result of underwater noise due to UXO clearance was estimated as 2,085 m due to detonation of charge size of 300 kg, however, with application of designed-in as well as secondary measures (including the use of ADD), risk of injury to grey seal will be reduced to low. In terms of fleeing response, up to 156 animals were predicted at risk to experience TTS at a maximum range of 6,430 m due to detonation of charge size of 300 kg. Although high-order detonation is assessed as a maximum design scenario, low order techniques will be applied as the intended methodology for clearance of UXO. Underwater noise modelling predicted that grey seal can potentially experience TTS at the maximum range of 455 m due to detonation of 0.5 kg clearance shot following low order clearance with up to one grey seal potentially affected. TTS is a temporary hearing impairment and therefore animals are likely to fully recover from the effect. Therefore, 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 the Isle of May SAC. Given that this effect is short in duration, connectivity with important habitats within and outside the site is also unlikely to be impaired. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, grey seal, during the construction phase as a result of underwater noise during UXO clearance.

d: Injury and disturbance to marine mammals from elevated underwater noise due to vessel use and other activities – The threshold for injury is not exceeded by any vessel with the exception of rock placement vessels, for which an injury range of 5 m from the source was reported. With regard to behavioural disturbance to grey seals, cable laying activities result in the greatest modelled disturbance ranges out to 4,389 m. Grey seal is likely to be sensitive to disturbance from vessel traffic, however, most of the vessel traffic associated with construction and decommissioning will take place within the Proposed Development array area and Proposed Development export cable corridor and the overlap of noise disturbance contours with the boundaries of the Isle of May SAC is unlikely. Construction and decommissioning activities will be carried out over a medium term. Operation and maintenance activities will occur over the full lifetime of the project (estimated to be 35 years), however, only a small proportion of vessel use and other activities will occur at any one time. Since the behavioural effect is considered to be highly reversible, it is highly unlikely that it will influence grey seal population trajectory in the long-term. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, grey seal, during the construction, operation and maintenance and decommissioning phases as a result of underwater noise due to vessel noise and other activities.

e: Changes in fish and shellfish communities affecting prey availability – Changes to the prey species may occur due to temporary and long-term habitat loss/disturbance, increased SSC and associated sediment deposition, and injury and/or disturbance from underwater noise and vibration. However, given that the impacts will be highly localised and largely restricted to the boundaries of the Proposed Development, only a small area will be affected when compared to available foraging habitat for grey seals in the northern North Sea. It is expected that grey seal population would be able to tolerate the effect without any impact on reproduction and survival rates. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, grey seal, during the construction, operation and maintenance and decommissioning phases as a result of changes in fish and shellfish communities affecting prey availability.

f: In-combination – the in-combination assessment considered the potential for underwater noise during piling, UXO clearance, site-investigation surveys, vessel use and other activities and changes in fish and shellfish communities affecting prey availability from the Proposed Development alone to interact with similar effects arising from other projects included in the Tier 2 and Tier 3 assessments. In-combination effects are not predicted to result in effects of greater significance than as assessed for the Proposed Development alone. It is therefore concluded that there is no potential for Adverse Effects on Integrity on the Annex II marine mammal qualifying interest feature of the site, grey seal, during the construction and decommissioning or operation and maintenance phases in-combination with other projects.

Table 15.10: Integrity Matrix for Annex II Marine Mammal Species of the Firth of Tay and Eden Estuary SAC

× - no Adverse Effect on Integrity

 - Adverse Effects on Integrity

a: Injury and disturbance from elevated underwater noise during piling –  The maximum range for injury to harbour seal as a result of underwater noise due to piling was estimated as 118 m. However, with application of designed-in measures, including visual and acoustic monitoring as well as secondary measures (the use of ADD), risk of injury to grey seal will be reduced to negligible. In terms of behavioural disturbance, a maximum of three animals could be potentially affected. The population of harbour seals in Firth of Tay and Eden Estuary SAC is known to be in decline since the early 2000s and therefore this population is deemed sensitive to any additional anthropogenic disturbance, especially during the breeding season. The outer behavioural disturbance noise contours as a result of piling do not overlap with Firth of Tay and Eden Estuary SAC. Harbour seal in inshore waters could experience mild disturbance where these areas overlap with 135 dB disturbance contour, but prolonged or sustained behavioural effects, including displacement, are unlikely to occur. During piling, there is the potential for some animals to be temporarily deterred from the offshore areas. Harbour seals although initially displaced due to pile-driving, are likely to return to the same area on subsequent trips following cessation of piling and therefore it is anticipated that the connectivity with areas of high importance within and outside the site will not be impaired. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, harbour seal, during the construction phase as a result of underwater noise during piling.

b: Injury and disturbance to marine mammals from elevated underwater noise during site investigation surveys – The maximum range for injury to harbour seal as a result of underwater noise during site-investigation surveys was estimated as 65 m, however, with application of designed-in measures, risk of injury to harbour seal will be reduced to negligible. In terms of behavioural disturbance, the largest distance over which disturbance could occur is out to approximately 7.5 km during vibro-coring. Due to the distance from the Firth of Tay and Eden Estuary SAC, the overlap of behavioural disturbance ranges with site boundaries is unlikely. The surveys will take place over a period of up to three months during the construction phase and routinely over 35 year life cycle of project. Although there is a potential for harbour seal to experience behavioural disturbance during the vibro-core survey (outside of the SAC), the surveys are expected to be very short in duration with animals returning to baseline levels soon after surveys have ceased. Underwater noise during site investigation surveys is unlikely to affect harbour seal from Firth of Tay and Eden Estuary SAC at a level that would substantially affect their behaviour and cause change in reproduction and survival rates. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, harbour seal, during the construction and operation phases as a result of underwater noise during site investigation surveys.

c: Injury and disturbance to marine mammals from elevated underwater noise during UXO clearance – The maximum range for injury to harbour seal as a result of underwater noise due to UXO clearance was estimated as 2,085 m due to detonation of charge size of 300 kg, however, with application of designed-in as well as secondary measures (including the use of ADD), risk of injury to grey seal will be reduced to low. In terms of behavioural disturbance, up to one animal was predicted at risk to experience TTS at a maximum range of 6,430 m due to detonation of charge size of 300 kg. Although high-order detonation is assessed as a maximum design scenario, low order techniques will be applied as the intended methodology for clearance of UXO and as a result the impact range will be reduced to 455 m due to detonation of 0.5 kg clearance shot following low order clearance. TTS is a temporary hearing impairment and therefore animals are likely to fully recover from the effect. Therefore, 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 the Firth of Tay and Eden Estuary SAC. Given that this effect is short in duration, connectivity with important habitats within and outside the site is also unlikely to be impaired. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, harbour seal, during the construction phase as a result of underwater noise during UXO clearance.

d: Injury and disturbance to marine mammals from elevated underwater noise due to vessel use and other activities – The threshold for injury is not exceeded by any vessel with the exception of rock placement vessels, for which an injury range of 5 m from the source was reported. With regard to behavioural disturbance to harbour seals, cable laying activities result in the greatest modelled disturbance ranges out to 4,389 m. Harbour seal is likely to be sensitive to disturbance from vessel traffic, however, most of the vessel traffic associated with construction and decommissioning will take place within the Proposed Development array area and Proposed Development export cable corridor and the overlap of noise disturbance contours with the boundaries of the Firth of Tay and Eden Estuary SAC is unlikely. Construction and decommissioning activities will be carried out over a medium term. Operation and maintenance activities will occur over the full lifetime of the project (estimated to be 35 years), however, only a small proportion of vessel use and other activities will occur at any one time. Since the behavioural effect is considered to be highly reversible, it is highly unlikely that it will influence harbour seal population trajectory in the long-term. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, harbour seal, during the construction, operation and maintenance and decommissioning phases as a result of underwater noise due to vessel noise and other activities

e: Changes in fish and shellfish communities affecting prey availability – Changes to the prey species may occur due to temporary and long-term habitat loss/disturbance, increased SSC and associated sediment deposition, and injury and/or disturbance from underwater noise and vibration. The impacts will be highly localised and largely restricted to the boundaries of the Proposed Development. Areas within the Proposed Development array area and Proposed Development export cable corridor are not characterised by high densities of harbour seal telemetry tracks and therefore these areas are highly unlikely to represent important foraging grounds for this species. However, for these individuals visiting Proposed Development to find prey, it is expected that harbour 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. It is expected that harbour seal population would be able to tolerate the effect without any impact on reproduction and survival rates. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, harbour seal, during the construction, operation and maintenance and decommissioning phases as a result of changes in fish and shellfish communities affecting prey availability.

f: In-combination – the in-combination assessment considered the potential for underwater noise during piling, UXO clearance, site-investigation surveys, vessel use and other activities and changes in fish and shellfish communities affecting prey availability from the Proposed Development alone to interact with similar effects arising from other projects included in the Tier 2 and Tier 3 assessments. In-combination effects are not predicted to result in effects of greater significance than as assessed for the Proposed Development alone. It is therefore concluded that there is no potential for Adverse Effects on Integrity on the Annex II marine mammal qualifying interest feature of the site, harbour seal, during the construction and decommissioning or operation and maintenance phases in-combination with other projects.

Table 15.11: Integrity Matrix for Annex II Marine Mammal Species of the Southern North Sea SAC

× - no Adverse Effect on Integrity

 - Adverse Effects on Integrity

a: Injury and disturbance from elevated underwater noise during piling –  The maximum range for injury to harbour porpoise as a result of underwater noise due to piling was estimated as 449 m. However, with application of designed-in measures, including visual and acoustic monitoring as well as secondary measures (the use of ADD), risk of injury to harbour porpoise will be reduced to negligible. There will be no overlap of noise disturbance contours with the Southern North Sea SAC, however, there is a potential for individuals from this SAC to be present within noise disturbance contours with up to 2,822 animals potentially affected. However, considering the distance from the Proposed Development to the SAC, it is a highly precautionary assumption that 100% of disturbed animals will come from this SAC. The Firth of Forth and Tay area is unlikely to represent important breeding or foraging habitat for harbour porpoise that would not be available elsewhere within the species’ home range over the North Sea. If individuals are deterred from the foraging grounds in the vicinity of the Proposed Development, it can be anticipated that harbour porpoise can compensate for any resulting loss in energy intake by increasing foraging activities beyond impact zone. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, harbour porpoise, during the construction phase as a result of underwater noise during piling.

b: Injury and disturbance to marine mammals from elevated underwater noise during site investigation surveys – The maximum range for injury to harbour porpoise as a result of underwater noise during site-investigation surveys was estimated as 360 m, however, with application of designed-in measures, risk of injury to harbour porpoise will be reduced to negligible. In terms of behavioural disturbance, the largest distance over which disturbance could occur potentially affecting harbour porpoise is out to approximately 7.5 km during vibro-coring. Site investigation surveys are expected to be short in duration with animals returning to baseline levels soon after surveys have ceased. Site investigation activities will not take place within or nearby to the SAC and therefore will not exclude harbour porpoise from relevant proportion from the SAC. It will not alter the distribution of harbour porpoise such that recovery cannot be expected or effects on Southern North Sea SAC population can be considered long term. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, harbour porpoise, during the construction and operation phases as a result of underwater noise during site investigation surveys.

c: Injury and disturbance to marine mammals from elevated underwater noise during UXO clearance – The maximum range for injury to harbour porpoise as a result of underwater noise due to UXO clearance was estimated as 10,630 m due to detonation of charge size of 300 kg. Given that there is a potential to experience auditory injury by nominal number of individuals at a greater range than can be mitigated by application of an ADD and soft-start charges, prior to the commencement of UXO clearance works, a more detailed assessment will be produced as a part of the EPS licence supporting information for the UXO clearance works. Appropriate mitigation measures will be agreed with stakeholders as a part of a UXO specific MMMP. In terms of behavioural disturbance, animals were predicted at risk to experience TTS at a maximum range of 19 km due to detonation of charge size of 300 kg. UXO clearance activities will not take place within or nearby to the Southern North Sea SAC and therefore will not exclude harbour porpoise from the relevant area of the site up to the threshold limit (20% in any given day or 10% over a season). It will not alter the distribution of harbour porpoise such that recovery cannot be expected or effects on Southern North Sea SAC population can be considered long term. Additionally, TTS is a temporary hearing impairment and therefore animals are likely to fully recover from the effect. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, harbour porpoise, during the construction phase as a result of underwater noise during UXO clearance.

d: Changes in fish and shellfish communities affecting prey availability – Changes to the prey species may occur due to temporary and long-term habitat loss/disturbance, increased SSC and associated sediment deposition, and injury and/or disturbance from underwater noise and vibration. The impacts will be highly localised and restricted to the boundaries of the Proposed Development. Firth of Forth and Tay area is unlikely to represent important breeding or foraging habitat that would not be available elsewhere within the species home range over the North Sea. It is therefore anticipated that the availability of suitable foraging grounds for harbour porpoise will not be impaired and availability of prey will be maintained within the wider distributional range. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, harbour porpoise, during the construction, operation and maintenance and decommissioning phases as a result of changes in fish and shellfish communities affecting prey availability.

e: In-combination – the in-combination assessment considered the potential for underwater noise during piling, UXO clearance, site-investigation surveys, vessel use and other activities and changes in fish and shellfish communities affecting prey availability from the Proposed Development alone to interact with similar effects arising from other projects included in the Tier 2 and Tier 3 assessments. In-combination effects are not predicted to result in effects of greater significance than as assessed for the Proposed Development alone. It is therefore concluded that there is no potential for Adverse Effects on Integrity on the Annex II marine mammal qualifying interest feature of the site, harbour porpoise, during the construction and decommissioning or operation and maintenance phases in-combination with other projects.

Table 15.12: Integrity Matrix for Annex II Marine Mammal Species of the Moray Firth SAC

× - no Adverse Effect on Integrity

 - Adverse Effect on Integrity

a: Injury and disturbance from elevated underwater noise during piling –  The maximum range for injury to bottlenose dolphin as a result of underwater noise due to piling was estimated as 43 m. However, with application of designed-in measures, including visual and acoustic monitoring as well as secondary measures (including the use of ADD), risk of injury to bottlenose dolphin will be reduced to negligible. There is no potential for overlap of noise disturbance contours with this designated site, however, noise contours have the potential to overlap with the main distributional range of its population. Up to five animals from the Moray Firth SAC population could experience mild disturbance but this is unlikely to lead to barrier effects as animals are unlikely to be excluded from the coastal areas. Therefore, behavioural disturbance is unlikely to alter the distribution of bottlenose dolphin such that recovery cannot be expected or effects can be considered long term. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, bottlenose dolphin, during the construction phase as a result of underwater noise during piling.

b: Injury and disturbance to marine mammals from elevated underwater noise during site investigation surveys – The maximum range for injury to bottlenose dolphin as a result of underwater noise during site-investigation surveys was estimated as 65 m, however, with application of designed-in measures, risk of injury to bottlenose dolphin will be reduced to negligible. In terms of behavioural disturbance, the largest distance over which disturbance could occur potentially affecting bottlenose dolphin is out to approximately 7.5 km during vibro-coring. There is no potential for overlap of noise disturbance contours with the boundary of the SAC. Due to the distance from the coast, if surveys are taking place within the Proposed Development array area, bottlenose dolphins are unlikely to be affected. If site investigation surveys are taking place along Proposed Development array area and export cable corridor, located in the southern limit of the main distributional range of bottlenose dolphin, there is a potential for overlap of disturbance ranges with coastal areas. However, the results of ECOMMAS study suggest that the abundance of bottlenose dolphin in the southern part of the CES (in proximity to St Abbs) is low. Given that the surveys are considered to be short-term, the number of animals potentially disturbed would represent a negligible proportion of the population. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, bottlenose dolphin, during the construction and operation phases as a result of underwater noise during site investigation surveys.

c: Injury and disturbance to marine mammals from elevated underwater noise during UXO clearance – The maximum range for injury to bottlenose dolphin as a result of underwater noise due to UXO clearance was estimated as 615 m due to detonation of charge size of 300 kg, however, with application of designed-in as well as secondary measures (including the use of ADD), risk of injury to bottlenose dolphin will be reduced to low. In terms of fleeing response, animals were predicted at risk to experience TTS at a maximum range of 1,137 m due to detonation of charge size of 300 kg. Although high-order detonation is assessed as a maximum design scenario, low order techniques will be applied as the intended methodology for clearance of UXO and as a result the impact range will be reduced to 135 m due to detonation of 0.5 kg clearance shot. Due to the distance from the coast, if UXO clearance is taking place within the Proposed Development array area, bottlenose dolphins are unlikely to be affected. If UXO clearance is taking place along Proposed Development array area and export cable corridor, located in the southern limit of the main distributional range of bottlenose dolphin, there is a potential for overlap of disturbance ranges with coastal areas. However, the results of ECOMMAS study suggest that the abundance of bottlenose dolphin in the southern part of the CES (in proximity to St Abbs) in low. Additionally, TTS is a temporary hearing impairment and therefore animals are likely to fully recover from the effect. Given that this effect is short in duration, connectivity with important habitats outside the SAC is also unlikely to be impaired. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, bottlenose dolphin, during the construction phase as a result of underwater noise during UXO clearance.

d: Injury and disturbance to marine mammals from elevated underwater noise due to vessel use and other activities – The threshold for injury is not exceeded by any vessel with the exception of installation/construction and rock placement vessels, for which an injury range of 15 m from the source was reported. With regard to behavioural disturbance to bottlenose dolphin, the greatest modelled disturbance range is out to 4,389 m. All vessel movements will take place outside the Moray Firth SAC and there is no potential for overlap of injury or disturbance ranges with the boundaries of the site. As most vessel movements will be confined within the Proposed Development array area, there is a limited potential for overlap of maximum injury or behavioural disturbance ranges with coastal areas. For vessel use and other activities taking place along Proposed Development array area and export cable corridor, located the southern limit of the main distributional range of bottlenose dolphin, there is a potential for overlap of disturbance ranges with coastal areas. However, the results of ECOMMAS study suggest that the abundance of bottlenose dolphin in the southern part of the CES (in proximity to St Abbs) in low. Therefore, if individuals are affected by disturbance as a result by vessel movements and other activities in the vicinity of the Proposed Development export cable corridor and landfall, these numbers would represent a negligible proportion of the population from Moray Firth SAC. Construction and decommissioning activities will be carried out over a medium term. Operation and maintenance activities will occur over the full lifetime of the project (estimated to be 35 years), however, only a small proportion of vessel use and other activities will occur at any one time. Since the behavioural effect is considered to be highly reversible, it is highly unlikely that it will influence bottlenose dolphin population trajectory in the long-term. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, bottlenose dolphin, during the construction, operation and maintenance and decommissioning phases as a result of underwater noise due to vessel noise and other activities.

e: Changes in fish and shellfish communities affecting prey availability – Changes to the prey species may occur due to temporary and long-term habitat loss/disturbance, increased SSC and associated sediment deposition, and injury and/or disturbance from underwater noise and vibration. The impacts will be highly localised and restricted to the boundaries of the Proposed Development. Since the Moray Firth SAC and the Tay estuary are known to be important foraging ground for bottlenose dolphins within the CES MU and neither of these important areas will be affected by impacts considered in the assessment, bottlenose dolphin distribution and connectivity with important foraging habitats within and outside the site is unlikely to be impaired. As such, it is concluded that there is no potential for Adverse Effects on Integrity on Annex II marine mammal qualifying interest features of the site, bottlenose dolphin, during the construction, operation and maintenance and decommissioning phases as a result of changes in fish and shellfish communities affecting prey availability.

f: In-combination – the in-combination assessment considered the potential for underwater noise during piling, UXO clearance, site-investigation surveys, vessel use and other activities and changes in fish and shellfish communities affecting prey availability from the Proposed Development alone to interact with similar effects arising from other projects included in the Tier 2 and Tier 3 assessments. In-combination effects are not predicted to result in effects of greater significance than as assessed for the Proposed Development alone. It is therefore concluded that there is no potential for Adverse Effects on Integrity on the Annex II marine mammal qualifying interest feature of the site, bottlenose dolphin, during the construction and decommissioning or operation and maintenance phases in-combination with other projects.