10. Marine Mammals

10.1. Introduction

  1. This chapter of the Array Environmental Impact Assessment (EIA) Report presents the assessment of the likely significant effects (as per the EIA Regulations) on marine mammals as a result of the Ossian Array which is the subject of this application (hereafter referred to as “the Array”). Specifically, this chapter assesses the likely significant effects of the Array on marine mammals during the construction, operation and maintenance, and decommissioning phases.
  2. Likely significant effect is a term used in both the EIA Regulations and the Habitat Regulations. Reference to likely significant effect in this Array EIA Report refers to likely significant effect (LSE1) as used by the EIA Regulations. This Array EIA Report is accompanied by a Report to Inform Appropriate Assessment (RIAA) (Ossian OWFL, 2024) which uses the term as defined by the Habitats Regulations.
  3. The following technical chapters also inform the assessment presented in this chapter:
  • volume 2, chapter 7: Physical Processes;
  • volume 2, chapter 9: Fish and Shellfish Ecology; and
  • volume 2, chapter 13: Shipping and Navigation.
  1. This chapter also summarises information contained within volume 3, appendix 10.2. The technical report provides a detailed characterisation of the marine mammal species ecology within the vicinity of the Array and the wider northern North Sea, based on existing literature and site-specific surveys, and provides information on marine mammal species of ecological importance and conservation value. This chapter is also informed by volume 3, appendix 10.1 which models the predicted underwater noise emissions associated with the construction and installation of the Array.

10.2. Purpose of the Chapter

  1. The Array EIA Report provides the Scottish Ministers, statutory and non-statutory stakeholders with adequate information to determine the LSE1 of the Array on the receiving environment. This is further outlined in volume 1, chapter 3.
  2. The purpose of this marine mammals Array EIA Report chapter is to:
  • summarise the existing environmental baseline established from desk studies, site-specific surveys and telemetry data as well as consultation with stakeholders;
  • identify any assumptions and limitations encountered in compiling the environmental information;
  • present results of underwater noise modelling;
  • present the environmental impacts on marine mammals arising from the Array and reach a conclusion on the significance of effects on marine mammals, based on the information gathered and the analysis and assessments undertaken; and
  • highlight any necessary monitoring and/or mitigation measures which are recommended to prevent, minimise, reduce or offset the likely significant adverse environmental effects of the Array on marine mammals.

10.3. Study Area

  1. For the purpose of this chapter, two study areas have been defined. Figure 10.1   Open ▸ illustrates the marine mammal study areas for the Array as follows:
  1. These study areas are as described in the Array EIA Scoping Report (Ossian OWFL, 2023), and the use of the two marine mammal study areas has been agreed with MD-LOT via the Scoping Opinion in June 2023 (see Table 10.10   Open ▸ ).

10.4. Policy and Legislative Context

  1. Volume 1, chapter 2 presents the policy and legislation of relevance to renewable energy infrastructure. Policy and legislation specifically in relation to marine mammals is contained in the Marine and Coastal Access Act 2009, the Habitats Regulations[1] (see volume 1, chapter 2 for more details on this collective term), Scotland’s National Marine Plan 2015, The Sectoral Marine Plan for Offshore Wind Energy 2020, Nature Conservation (Scotland) Act 2004 and the United Kingdom (UK) Marine Policy Statement.
  2. A summary of the legislative provisions and policy frameworks relevant to marine mammals is provided in Table 10.1   Open ▸ to Table 10.9   Open ▸ . Further detail is presented in volume 1, chapter 2.


Figure 10.1:
Marine Mammal Study Areas

Figure 10.1:  Marine Mammal Study Areas


Table 10.1:
Summary of Marine and Coastal Access (MCAA) Act 2009 Relevant to Marine Mammals

Table 10.1: Summary of Marine and Coastal Access (MCAA) Act 2009 Relevant to Marine Mammals

 

Table 10.2:
Summary of Marine (Scotland) Act 2010 Relevant to Marine Mammals

Table 10.2: Summary of Marine (Scotland) Act 2010 Relevant to Marine Mammals

 

Table 10.3:
Summary of the Habitats Regulations Relevant to Marine Mammals

Table 10.3: Summary of the Habitats Regulations Relevant to Marine Mammals

 

Table 10.4:
Summary of Scotland’s National Marine Plan (2015) Relevant to Marine Mammals

Table 10.4: Summary of Scotland’s National Marine Plan (2015) Relevant to Marine Mammals

 

Table 10.5:
Summary of PMFs in Scotland’s Seas – Habitats Relevant to Marine Mammals (NatureScot, 2020)

Table 10.5: Summary of PMFs in Scotland’s Seas – Habitats Relevant to Marine Mammals (NatureScot, 2020)

 

Table 10.6:
Summary of The Sectoral Marine Plan for Offshore Wind Energy 2020[2] Relevant to Marine Mammals

Table 10.6: Summary of The Sectoral Marine Plan for Offshore Wind Energy 2020[2] Relevant to Marine Mammals

 

Table 10.7:
Summary of the UK Marine Policy Statement Relevant to Marine Mammals

Table 10.7: Summary of the UK Marine Policy Statement Relevant to Marine Mammals

 

Table 10.8:
Summary of the Nature Conservation (Scotland) Act 2004 Relevant to Marine Mammals

Table 10.8: Summary of the Nature Conservation (Scotland) Act 2004 Relevant to Marine Mammals

 

Table 10.9:
Summary of The Scottish Biodiversity Strategy (Scottish Government 2023) Relevant to Marine Mammals

Table 10.9: Summary of The Scottish Biodiversity Strategy (Scottish Government 2023) Relevant to Marine Mammals