Gannet
  1. The combined mortality from displacement and collision (using a simple additive approach of the values in Table 5.90   Open ▸ and Table 5.135   Open ▸ ) is presented in Table 5.170   Open ▸ . The approach sums the collision and disturbance impacts, with potential for double counting inherent in that approach.

 

Table 5.170:
Gannet Combined Displacement and Collision Mortalities Apportioned to the Forth Islands SPA In-Combination Totals

Table 5.170: Gannet Combined Displacement and Collision Mortalities Apportioned to the Forth Islands SPA In-Combination Totals

 

  1. With a population of 150,518 breeding adults (Burnell et al., 2023), 696.5 to 1,204.8 additional mortalities represents a 0.463 to 0.800 percentage point increase in mortality rates. Therefore, PVA has been carried out both with and without Berwick Bank Offshore Wind Farm and for the high and low scenarios, to further assess the total in-combination impact.
  2. The PVA results are summarised in Table 5.171   Open ▸ . Full details are available in appendix 3B.

 

Table 5.171:
Summary of PVA Results for In-Combination Displacement and Collision Impacts on Gannet at the Forth Islands SPA

Table 5.171: Summary of PVA Results for In-Combination Displacement and Collision Impacts on Gannet at the Forth Islands SPA

 

  1. The gannet population of the Forth Islands SPA increased significantly from its citation level of 43,200 breeding adults to counts of 150,518 breeding adults from the census conducted in 2014 as part of the gannet census (Burnell et al., 2023). However, that data pre-dates the HPAI outbreak. Counts conducted in 2023 estimate the gannet population of Bass Rock to be 51,844 AOS (103,688 breeding adults), representing a significant decline (Harris et al., 2023). Whilst this decline is dramatic, the population remains above its citation level, and the available evidence suggests that the population is already showing signs of recovery (Tyndall et al., 2024). It is evident from the prior growth that there are ample suitable nesting sites on Bass Rock, and sufficient prey within foraging range to support a larger population. Therefore, it would be expected that the population will be able to rapidly recover.
  2. The CGR ranges from 0.991 to 0.995. The CPS ranges from 0.712 to 0.822. Whilst the gannet population of the Forth Islands SPA had been growing prior to HPAI, this is a magnitude of impact that could lead to a population decline, which, combined with the impact of HPAI, would be contrary to the conservation objectives of the site.
  3. Therefore, it is concluded that there is a potential AEOI to the gannet feature of the Forth Islands SPA as a result of combined collision and displacement impacts from the Array in combination with other developments.
  4. It should, however, be noted that the approach to collision risk modelling used by both the Array and many other developments considered in the in-combination totals do not incorporate a macro-avoidance factor, in line with the current guidance from NatureScot. Natural England advise to apply a 65-85% macro avoidance rate when modelling gannet collisions (MD-LOT, 2023) which would reduce the collision mortality by the same amount. NatureScot have indicated they are reviewing their position on this matter (MD-LOT, 2023). If a 65-85% macro avoidance rate was applied, the overall impact would most likely no longer be a magnitude that could be considered to cause an AEOI.
  5. Similarly, the displacement impact will be overestimated, as any birds that suffer mortality as a result of collision could not also be subject to displacement impacts.
  6. Therefore, under the current approach to assessment, it must be concluded that the in-combination total displacement and collision risk reaches a magnitude that would be an AEOI to the gannet feature of the Forth Islands SPA.
  7. However, this approach is considered highly over-precautionary, and under a more realistic approach an AEOI would not be expected to occur.

                        Breeding Seabird Assemblage

  1. Of the components of the breeding seabird assemblage, only kittiwake and gannet were found to have any potential LSE2 for collision risk. The assessments for these species are presented above. The gannet population is expected to grow, whilst the kittiwake population is expected to decline. Given the kittiwake population has already declined significantly from its population size at the time the site was designated, this further decline is of a level that has the potential to result in the loss of kittiwake as a viable component of the assemblage.
  2. Therefore, it is concluded that there is a potential AEOI to the seabird assemblage feature of the Forth Islands SPA, resulting from the combined displacement and collision risk, from the Array in combination with other developments.
                        Fowlsheugh SPA
                        Kittiwake
  1. The combined mortality from displacement and collision (using a simple additive approach of the values in Table 5.93   Open ▸ and Table 5.138   Open ▸ ) is presented in Table 5.172   Open ▸ . The approach sums the collision and disturbance impacts, with potential for double counting inherent in that approach.

 

Table 5.172:
Kittiwake Combined Displacement and Collision Mortalities Apportioned to the Fowlsheugh SPA In-Combination Totals

Table 5.172: Kittiwake Combined Displacement and Collision Mortalities Apportioned to the Fowlsheugh SPA In-Combination Totals

 

  1. With a population of 28,078 breeding adults (Burnell et al., 2023), 97.5 to 266.5 additional mortalities represents a 0.347 to 0.949 percentage point increase in mortality rates. Therefore, PVA has been carried out both with and without Berwick Bank Offshore Wind Farm and for the high and low scenarios, to further assess the total in-combination impact.
  2. The PVA results are summarised in Table 5.173   Open ▸ . Full details are available in appendix 3B.

 

Table 5.173:
Summary of PVA Results for In-Combination Displacement and Collision Impacts on Kittiwake at the Fowlsheugh SPA

Table 5.173: Summary of PVA Results for In-Combination Displacement and Collision Impacts on Kittiwake at the Fowlsheugh SPA

 

  1. The kittiwake population of the Fowlsheugh SPA has decreased between its citation level of 73,300 breeding adults and Seabird Census counts of 28,078 breeding adults (Burnell et al., 2023). However, more recent counts, that were conducted following the HPAI outbreak, indicate the population may be increasing again, with 15,443 AON (30,966 breeding adults) recorded in 2023 (Tremlett et al., 2024).
  2. The PVA results show that the kittiwake population is expected to remain relatively stable under the counterfactual (no impact) scenario. Under the impacted scenarios, the CGR is 0.989 to 0.996. This leads to a CPS after 35 years of 0.666 to 0.862 – i.e. the population size would be 13.8% to 33.4% smaller than the counterfactual population size.
  3. This level of impact is considered small to moderate (depending on the scenario and the approach), and in the context of a population that is already declining, the additional mortality from the Array in combination with other projects and plans would appear to have the potential to adversely affect the likelihood of the site meeting its conservation objectives. Therefore, it is concluded that there is a potential AEOI to the kittiwake feature of the Fowlsheugh SPA as a result of combined displacement and collision impacts from the Array in-combination with other developments.

                        Breeding Seabird Assemblage

  1. Of the components of the seabird assemblage, kittiwake was the only species for which a potential LSE2 was identified for combined displacement and collision risk. As detailed above, there is expected to be a significant impact on the kittiwake population. The kittiwake population at citation was significantly higher than the current population. Whilst the magnitude of the impact would not be deemed sufficient to risk entirely losing kittiwake as a viable component of the assemblage, the decline is sufficient to adversely affect the total population size of the seabird assemblage.
  2. Razorbill are not considered vulnerable to collision risk and therefore no assessment is presented in this section for combined collision and displacement. However, when assessing the overall impact on the seabird assemblage, consideration also needs to be given to the impact of displacement on razorbill, which is presented in section 5.5.2. Those results concluded a negligible impact to the razorbill population as a component of the seabird assemblage under the low approach to assessment, or a small impact under the high approach to assessment.
  3. Therefore, it is concluded that there is a potential AEOI to the seabird assemblage feature of the Fowlsheugh SPA as a result of the impact of combined displacement and collision from the Array in-combination with other developments.
                        Hermaness, Saxa Vord and Valla Field SPA
                        Gannet
  1. The combined mortality from displacement and collision (using a simple additive approach of the values in Table 5.99   Open ▸ and Table 5.141   Open ▸ ) is presented in Table 5.174   Open ▸ . The approach sums the collision and disturbance impacts, with potential for double counting inherent in that approach.

 

Table 5.174:
Gannet Combined Displacement and Collision Mortalities Apportioned to the Hermaness, Saxa Vord and Valla Field SPA In-Combination Totals

Table 5.174: Gannet Combined Displacement and Collision Mortalities Apportioned to the Hermaness, Saxa Vord and Valla Field SPA In-Combination Totals

 

  1. With a population of 59,124 breeding adults (Burnell et al., 2023), 88.7 to 125.0 additional mortalities represents a 0.150 to 0.211 percentage point increase in mortality rates. Therefore, PVA has been carried out both with and without Berwick Bank Offshore Wind Farm and for the high and low scenarios, to further assess the total in-combination impact.
  2. The PVA results are summarised in Table 5.175   Open ▸ . Full details are available in appendix 3B.

 

Table 5.175:
Summary of PVA Results for In-Combination Displacement and Collision Impacts on Gannet at the Hermaness, Saxa Vord and Valla Field SPA

Table 5.175: Summary of PVA Results for In-Combination Displacement and Collision Impacts on Gannet at the Hermaness, Saxa Vord and Valla Field SPA

 

  1. The gannet population of the Hermaness, Saxa Vord and Valla Field SPA has increased between its citation level of 32,800 breeding adults to recent counts of 59,124 breeding adults (Burnell et al., 2023).
  2. The CGR is 0.998. The CPS ranges from 0.915 to 0.939. When considering the growth of the gannet population within the Hermaness, Saxa Vord and Valla Field SPA, this level of impact is not of a magnitude that is expected to adversely affect the population from meeting its conservation objectives.
  3. It should be noted that even this level of impact is considered overly precautionary. The approach to collision risk modelling used by both the Array and many other developments considered in the in-combination totals do not incorporate a macro-avoidance factor, in line with the current guidance from NatureScot. Natural England advise to apply a 65-85% macro avoidance rate when modelling gannet collisions (MD-LOT, 2023), which would reduce the collision mortality by the same amount. NatureScot have indicated they are reviewing their position on this matter (MD-LOT, 2023).
  4. Similarly, the displacement impact will be overestimated, as any birds that suffer mortality as a result of collision could not also be subject to displacement impacts.
  5. Therefore, it is concluded, beyond reasonable scientific doubt, that there is no potential for an AEOI to the gannet feature of the Hermaness, Saxa Vord and Valla Field SPA as a result of displacement and collision from the Array in combination with other developments.

                        Breeding Seabird Assemblage

  1. Of the components of the seabird assemblage, gannet was the only species for which a potential LSE2 was identified. As detailed above, there is expected to be no AEOI on the gannet feature. Therefore, it can also be concluded, beyond reasonable scientific doubt, that there is no AEOI to the seabird assemblage feature of the Hermaness, Saxa Vord and Valla Field SPA as a result of collision from the Array in combination with other developments.