Kittiwake

                        Magnitude of impact

  1. In all three seasons (pre-breeding, breeding and post breeding) and also on an annual basis, the estimated increase in baseline mortality remains well below the 1% increase threshold ( Table 11.33   Open ▸ ), with the upper end of the range for increase in annual baseline mortality being 0.061%.
  2. The main value for assessment uses the CRM parameters advised by NatureScot to predict collision mortality, and a displacement rate of 30% and mortality rate of 3%. Using this rate, the increase in predicted mortality in the breeding season was 0.140%. In the pre-breeding increase in mortality was predicted to be 0.11% and in the post-breeding 0.008%
  3. The impact is predicted to be of local spatial extent, long-term duration, continuous and reversible. It is predicted that the impact will affect the receptor directly. The magnitude is therefore considered to be negligible to low.

Table 11.33:
Assessment of Predicted Combined Collision Risk and Displacement Impacts for Kittiwake on Seasonal and Annual Bases Against the Baseline Mortality of Relevant Regional Populations

Table 11.33: Assessment of Predicted Combined Collision Risk and Displacement Impacts for Kittiwake on Seasonal and Annual Bases Against the Baseline Mortality of Relevant Regional Populations

 

                        Sensitivity of the receptor
  1. Kittiwake were assessed as having low vulnerability to displacement impacts but higher vulnerability to collision impacts, and therefore considered to have medium vulnerability to the combined impact of displacement and collision.
  2. Kittiwake is a qualifying interest for several SPAs likely to be connected to the Array (within the mean-max + SD foraging range), with several non-SPA colonies also within range and so the species is considered to be of international value. Refer to Table 6.2 of volume 3, appendix 11.1 for details of SPAs with connectivity to the Array with regards to kittiwake.
  3. Kittiwake lay two eggs and breed from the age of three onwards, typically living on average for 12 years (Burnell et al., 2023). Kittiwake have undergone decreases of approximately 57% in Scotland since the early 2000s. Surveys managed by the RSPB in 2023 have recorded indicative increases of 8% across a number of sites in Britain in 2023 when compared against a pre-HPAI baseline (Tremlett et al., 2024). Overall, kittiwake is deemed to have low recoverability.
  4. Kittiwake is deemed to be of medium vulnerability, low recoverability and international value. The sensitivity of the receptor is therefore considered to be high.

                        Significance of the effect

  1. Overall, the magnitude of the impact is deemed to be negligible to low and the sensitivity of the receptor is considered to be high. The effect will, therefore, be of minor to moderate adverse significance. However, due to predicted increases in baseline mortality for all seasons and annually falling well below 1%, even at the upper range of parameters, it is considered that minor adverse significance is appropriate, which is not significant in EIA terms.

                        Secondary mitigation and residual effect

  1. No offshore ornithology secondary mitigation is considered necessary because the likely effect in the absence of mitigation is not significant in EIA terms.
Fulmar

                        Magnitude of impact

  1. In all four seasons (pre-breeding, breeding, post breeding and non-breeding) and also on an annual basis, the estimated increase in baseline mortality remains well below the 1% increase threshold ( Table 11.34   Open ▸ ), with the upper end of the range for increase in annual baseline mortality being 0.02%.
  2. The main value for assessment uses the CRM parameters advised by NatureScot to predict collision mortality, and a displacement rate of 30% and mortality rate of 1%. Using this rate, the predicted annual mortality is 0.005%.
  3. The impact is predicted to be of local spatial extent, long-term duration, continuous and reversible. It is predicted that the impact will affect the receptor directly. The magnitude is therefore, considered to be negligible.

 

Table 11.34:
Assessment of Predicted Combined Collision Risk and Displacement Impacts for Fulmar on Seasonal and Annual Bases Against the Baseline Mortality of Relevant Regional Populations

Table 11.34: Assessment of Predicted Combined Collision Risk and Displacement Impacts for Fulmar on Seasonal and Annual Bases Against the Baseline Mortality of Relevant Regional Populations

 

                        Sensitivity of the receptor
  1. Fulmar were assessed as having very low vulnerability to displacement impacts and very low vulnerability to collision impacts, and therefore considered to have very low vulnerability to the combined impact of displacement and collision.
  2. Fulmar is a qualifying interest for several SPAs likely to be connected to the Array (within the mean-max + SD foraging range), with several non-SPA colonies also within range and so the species is considered to be of international value. Refer to table 6.26 of volume 3, appendix 11.1 for details of SPAs with connectivity to the Array with regards to fulmar.
  3. Fulmar are considered to have very low reproductive potential, due to an average age of recruitment of nine years old and typically laying only a single egg (Robinson, 2005; Horswill and Robinson, 2015). The fulmar population increased by 77% between the 1969 to 1970 and 1985 to 1988 Censuses and remained relatively stable until the early 2000s. Numbers have since declined slightly since but remain above the level in 1969 to 1970 (JNCC, 2022). Overall, fulmar is deemed to have low recoverability.
  4. Fulmar is deemed to be of very low vulnerability, low recoverability and international value. The sensitivity of the receptor is therefore considered to be high.

                        Significance of the effect

  1. Overall, the magnitude of the impact is deemed to be negligible and the sensitivity of the receptor is considered to be high. The effect will, therefore, be of minor adverse significance, which is not significant in EIA terms.

                        Secondary mitigation and residual effect

  1. No offshore ornithology secondary mitigation is considered necessary because the likely effect in the absence of mitigation is not significant in EIA terms.
Gannet

                        Magnitude of impact

  1. In all three seasons (pre-breeding, breeding and post breeding) and also on an annual basis, the estimated increase in baseline mortality remains well below the 1% increase threshold ( Table 11.35   Open ▸ ), with the upper end of the range for increase in annual baseline mortality being 0.053%
  2. The main value for assessment uses the CRM parameters advised by NatureScot to predict collision mortality, and a displacement rate of 70% and mortality rate of 1% to 3%. Using this range, the predicted increase in baseline mortality was 0.026 to 0.039% in the breeding season.
  3. The impact is predicted to be of local spatial extent, long-term duration, continuous and reversible. It is predicted that the impact will affect the receptor directly. The magnitude is therefore considered to be negligible.

 

Table 11.35:
Assessment of Predicted Combined Collision Risk and Displacement Impacts for Gannet on Seasonal and Annual Bases Against the Baseline Mortality of Relevant Regional Populations

Table 11.35: Assessment of Predicted Combined Collision Risk and Displacement Impacts for Gannet on Seasonal and Annual Bases Against the Baseline Mortality of Relevant Regional Populations

 

                        Sensitivity of the receptor
  1. Gannet were assessed as having low vulnerability to displacement impacts but higher vulnerability to collision impacts, and therefore considered to have medium vulnerability to the combined impact of displacement and collision.
  2. Gannet is a qualifying interest for several SPAs likely to be connected to the Array (within the mean-max + SD foraging range), with several non-SPA colonies also within range and so the species is considered to be of international value. Refer to Table 6.30 of volume 3, appendix 11.1 for details of SPAs with connectivity to the Array with regards to gannet.
  3. Gannet have low reproductive potential given a typical age of first breeding of five years and typically laying only a single egg per breeding season. However, although gannet has a low reproductive potential, the species has demonstrated a consistent increasing trend in abundance since the 1990’s (JNCC, 2020). It is of note that the species has suffered from the outbreak of HPAI during the 2022 breeding season (Pearce-Higgins et al., 2023), with declines of 25% recorded at certain sites in Britain in 2023 when compared against a pre-HPAI baseline (Tremlett et al., 2024). Therefore, whilst the overall population has shown steady growth, HPAI has led to some short-term declines. Therefore, overall gannet is deemed to have low recoverability.
  4. Gannet is deemed to be of medium vulnerability, medium recoverability and international value. The sensitivity of the receptor is therefore considered to be high.

                        Significance of the effect

  1. Overall, the magnitude of the impact is deemed to be negligible to low and the sensitivity of the receptor is considered to be high. The effect will, therefore, be of minor to moderate adverse significance. However, due to predicted increases in baseline mortality for all seasons and annually falling well below 1%, even at the upper range of parameters, it is considered that minor adverse significance is appropriate, which is not significant in EIA terms.

                        Secondary mitigation and residual effect

  1. No offshore ornithology secondary mitigation is considered necessary because the likely effect in the absence of mitigation is not significant in EIA terms.