Abstract
It was concluded in the Moray West Report to Inform an Appropriate Assessment (RIAA) submitted in support of Moray West’s Offshore Wind Farm and Offshore Transmission Infrastructure (OfTI) consent application (July 2018) that the great black-backed gull feature of the East Caithness Cliffs SPA should be screened out of the RIAA for collision impacts. This was on the basis that results from a gull tracking study undertaken in the East Caithness Cliffs SPA in 2014 indicated that great black-back gull foraging activities during the breeding season were limited to coastal waters, with no foraging in the Moray West Site. It was therefore concluded that there was no connectivity between the Moray West Site and the great black-back gull population of the East Caithness Cliffs SPA (see RIAA Chapter 4 – Table 4.5.1 and Chapter 6 Section 6.6.6.13).
Consequently, no further assessment of potential effects on the great black-backed gull feature of the East Caithness Cliffs SPA for either the Moray West Site alone or in-combination effects was undertaken in the RIAA.
Comments received from SNH, MSS and RSPB following consultation on the RIAA, questioned whether the information provided on great black-back gulls was sufficient to inform an assessment of effects on the East Caithness Cliffs SPA. This was on the basis that the conclusions from the gull tagging study alone may not, in their opinion, be sufficient to support the conclusion of no connectivity and therefore the screening out of the great black-backed gull feature of the East Caithness Cliffs SPA from the RIAA.
In response to these comments, further information on the great black-backed gull feature of the East Caithness Cliffs SPA was provided in the Moray West Addendum Document (November, 2018). This included an assessment of the potential effects of Moray West on the great black‐backed gull interest feature of the East Caithness Cliffs SPA. This assessment concluded that the Moray West project alone would have no adverse effect on this interest feature. This was determined through the application of a number of refinements to the calculation of collision mortality considered together with evidence of no or very limited connectivity to the East Caithness Cliffs SPA breeding colony based on results from the gull tagging study and other evidence. Of the 0 – 1.6 adult birds in the breeding season calculated to be at risk from collision, it was concluded that the total number of collisions that can be apportioned back to the East Caithness Cliffs SPA will be 0 or close to 0. Furthermore, it was also calculated that no more than 0.14 of an adult plumaged bird associated with the colony at East Caithness Cliffs SPA is predicted to collide during the non‐breeding season.
It was therefore concluded in the Addendum Document (PART 1, Chapter 3 Section 3.7) that Moray West alone makes no (or no material) contribution to any in‐combination effects on the great black‐backed gull breeding colony of the East Caithness Cliffs SPA.
SNH, in their consultation response to the information presented in the Addendum Document, advised that insufficient information was available to reach a conclusion on in-combination effects on the great black-backed gull qualifying feature of the East Caithness Cliffs SPA (SNH, 2019). Moreover, Marine Scotland Science (MSS) advised that apportioning both breeding and non-breeding impacts for the three Moray Firth developments, in-combination, for the breeding and non-breeding season to East Caithness Cliffs SPA, together with a recalculation of collision mortality for Beatrice Offshore Wind Farm (BOWL) and Moray East for as built scenarios2 would further aid in the assessment.
Within the Addendum Document, PART 1, Chapter 3 (Moray West, 2018), a series of refinements were applied to the calculation of collision mortality for great black‐backed gull at Moray West. This approach is developed further in this document by applying similar refinements to Moray East and BOWL (for further details of information sources see Section 1.3.1 below) such as the use of updated project designs for Moray East and the removal of sabbaticals and immature birds from collisions apportioned to the East Caithness Cliffs SPA from these projects. Population Viability Analysis (PVA) modelling outputs are also presented to inform potential effects on the East Caithness Cliffs SPA at a population level. The PVA has been performed in single bird increments of bird deaths across the range of assessed in-combination impacts, as advised by Marine Scotland.