8.1 Desktop Study
- An initial desk-based review of literature and data sources to support this Offshore EIA Scoping Report has identified a number of data sources which provide coverage of the Proposed Development Array Area and proposed ECC. These are summarised in Apx. Table 8. 1 Open ▸ .
Apx. Table 8. 1: Summary of Key Desktop Reports for Fish and Shellfish Ecology
- In 2020, epibenthic 2m beam trawling at 15 sampling locations distributed across representative sediment types was undertaken to characterise epifaunal communities and inform the benthic subtidal and intertidal ecology baseline characterisation. The results of the epibenthic beam trawl survey, which include records of small demersal fish species present in the Proposed Development fish and shellfish study area, will be used to enhance the existing data for fish and shellfish. Epibenthic sampling was undertaken using a standard 2 m scientific beam trawl (Lowestoft design) fitted with a knotless 5 mm cod end liner.
- Other various papers on fish migration are also referenced as key reports such as Newton et al., 2017; Gardiner et al., 2018; Godfrey et al., 2015; Malcolm et al., 2015; Lothian et al., 2017; Malcolm et al.,2010.
Fish and Shellfish Designated Sites
- The Proposed Development does not overlap with any European designated sites but there are several protected areas for fish in East Scotland. Apx. Table 8. 2 Open ▸ provides an early indication of the designated sites (international and national) that may be considered within the EIA and HRA. This list will be refined in the EIA to also include sites that fall within the potential ZOI of the Proposed Development, which will be determined as part of the EIA process to include consideration of migratory fish species.
- A full screening of European sites with qualifying fish features will be undertaken in the LSE Screening Report for the Proposed Development. Relevant Annex II fish species of European designated sites screened into the fish and shellfish ecology assessment will be fully considered and assessed in the fish and shellfish Offshore EIAR section with the assessment on the European designated sites itself deferred to the RIAA.
- The screening to be undertaken in the fish and shellfish ecology Offshore EIAR section will also include nationally designated sites (i.e. SSSIs, MPAs, recommended and designated MCZs). Nationally designated sites and the relevant qualifying features screened into the assessment will also be fully considered and assessed in the fish and shellfish ecology Offshore EIAR section.
- Fish and Shellfish Designated Sites
Apx. Table 8. 2: Summary of Designated Sites for Fish and Shellfish in Proximity to the Proposed Development
8.3.2 Fish Assemblage
- Distribution of fish is determined by a range of factors including abiotic parameters such as water temperature, salinity, depth, local-scale habitat features and substrate type, and biotic parameters such as predator-prey interactions, competition and anthropogenic factors such as infrastructure and commercial fishing intensity.
- The fish assemblage of the northern North Sea fish and shellfish study area includes demersal, pelagic, migratory and elasmobranchs fish species. Demersal species include sandeel, whiting, lemon sole, ling, plaice, with pelagic species including herring, sprat and saithe likely to be found in the vicinity of the Proposed Development.
- In August 2020, 15 epibenthic beam trawls were collected across the Proposed Development Array Area and ECC options during the benthic subtidal surveys (as per Apx. Figure 7. 1 Open ▸ ). A total of 21 bony fish taxa representing 553 individuals were recorded from these epibenthic trawls undertaken across the Proposed Development benthic subtidal and intertidal ecology study area. The most abundant fish recorded in the trawls were common dab (167 individuals), long rough dab, lesser sandeel and gobies. This was consistent with the infaunal data collected which also recorded lesser sandeels. Lesser sandeel, common dab and long rough dab were recorded in trawls across the Proposed Development, while Pomatoschistus sp. was only recorded in trawls within the Proposed Development ECC. Two four-bearded rockling and angler fish were recorded across all trawls.
- To inform the fish and shellfish baseline characterisation for the Seagreen Alpha/Bravo EIA (Seagreen, 2012b), a total of 53 epibenthic trawls were conducted during the benthic surveys in 2011. Several species were observed including pogge, dab, goby, lesser sandeel, butterfish, plaice, whiting and cod. Of these species, dab, goby, and lesser sandeel were generally the most abundant and with up to 588 individuals recorded in a single trawl. Commercial species such as plaice, whiting and cod were also observed.
- In addition, elasmobranchs (sharks and rays) have been found distributed throughout the east coast of Scotland (Coull et al., 1998; Ellis et al., 2012; Baxter et al., 2011).
Diadromous Fish Species
- There is the potential for diadromous fish species to migrate to and from Scottish rivers in the vicinity of the Proposed Development and, therefore, they may migrate through the Proposed Development fish and shellfish study area to rivers during certain periods of the year (SNH, 2017a and National Biodiversity Network (NBN) Atlas, 2019).
- The fish and shellfish ecology assessment for Seagreen Alpha/Bravo (SSE Renewables, 2012) observed seven migratory species of relevance. These species include Atlantic salmon, sea trout, sea lamprey, river lamprey, European eel, Allis and twaite shad and sparling (European smelt). The species which were considered as having the greatest potential to be present within the vicinity of the Seagreen Alpha/Bravo were Atlantic salmon, sea trout, eels and the lampreys.
- For the purposes of the impact assessment, it will be assumed that the aforementioned species are likely to be present within the Proposed Development Array Area and/or proposed ECC, during key migration periods (e.g. adult migration to spawning rivers and smolt migration from natal rivers in the vicinity of the development). With respect to migratory fish species, the aim of the impact assessment will be to determine whether construction, operation and maintenance or decommissioning activities have the potential to lead to disruption to migration, e.g. construction noise potentially creating an effective barrier to fish migration. The timing of fish migration will therefore be an important element of the baseline characterisation and this will be collected through desktop data sources, including rod catch data from rivers on the east coast of Scotland (e.g. Tweed, Forth, Tay, Esk and Dee), recent papers (e.g. Newton et al., 2017; Gardiner et al., 2018; Godfrey et al., 2015; Malcolm et al., 2015) and Marine Scotland smolt survey data from the east coast of Scotland (Marine Scotland, 2018c).
- Commercial landing data provides an overview of species present within the northern North Sea fish and shellfish study area. Species most frequently caught include the brown crab, European lobster, great scallop, velvet swimming crab and squid. Other species caught in the area include green crab and whelks (ICES, 2018).
- The River South Esk, River Dee and River Spey SACs have primarily been designated as SACs due to the presence of the freshwater pearl mussel. The freshwater pearl mussel, whilst not present in the marine environment, is dependent on the Atlantic salmon smolting population (JNCC, undated). Should the Atlantic salmon population be adversely affected by the Proposed Development, this may have an indirect effect on freshwater pearl mussel populations.
- During the epibenthic trawls conducted for Seagreen Alpha/Bravo, several shellfish species were observed including great scallop and queen scallop (Seagreen, 2012b). Nephrops was also recorded during site-specific surveys for the Berwick Bank Wind Farm (including epibenthic beam trawls and seabed imagery). Underwater video survey data provided by Marine Scotland also showed that Nephrops abundance was high in the inshore waters of the southern parts of the spawning and nursery grounds (Seagreen, 2012b). Other species such as brown crab, lobster, velvet swimming crab, whelk and squid were either recorded in very low abundances or not observed at all in the in the benthic surveys but are all recognised as important commercial shellfish species within the northern North Sea fish and shellfish study area (Seagreen, 2018).
Spawning and/or Nursery Grounds
- Potential nursery and spawning areas in the North Sea for a range of species were identified by Coull et al. (1998), based on larvae, egg and benthic habitat survey data. Ellis et al. (2012) reviewed this data for several fin fish species in the North Sea, including herring, providing an updated understanding of areas of low and high intensity nursery and spawning grounds.
- Based on this data, spawning areas for several species overlap the Proposed Development fish and shellfish study area, including low-intensity spawning for cod and plaice, non-specified spawning for Nephrops, sprat, whiting, lemon sole and herring, and high-intensity for sandeel. Species with known spawning periods and nursery habitats identified within the Proposed Development fish and shellfish study area have been summarised in Apx. Table 8. 3 Open ▸ , and illustrated in Apx. Figure 8. 1 Open ▸ to Apx. Figure 8. 3 Open ▸ .
- Herring nursery grounds are widespread along the Scottish and Northumberland coastlines (Ellis et al., 2012), with post-larvae juveniles up to sub-adults that are yet to reach sexual maturity feeding here until migrating to feeding grounds further offshore where they remain until reaching sexual maturity (ICES, 2016). Herring are a commercially and ecologically important pelagic fish species and are common across much of the North Sea and is listed as a Scottish Priority Marine Feature (PMF) (Fauchald et al., 2011 and Casini et al., 2004). Herring utilise specific benthic habitats during spawning, which increases their vulnerability to activities impacting the seabed. Further, as a hearing specialist, herring are vulnerable to impacts arising from subsea noise.
- A review of spawning grounds suggests there is an overlap of the Proposed Development fish and shellfish study area with herring nursey grounds. This overlap occurs along the Proposed Development ECC towards landfall and is non-specified in intensity. A further review of the herring spawning and nursery grounds will be undertaken to support the fish and shellfish ecology assessment following guidelines set out by Boyle and New (2018) considering seabed sediment type and records of herring larvae from the IHLS over the past decade.
Apx. Table 8. 3: Key Species with geographic Spawning and Nursery Grounds Overlap with the Proposed Development (Coull et al., 1998 and Ellis et al., 2012)
Apx. Figure 8. 1: Cod, Nephrops, Whiting and Haddock Spawning and Nursery Grounds and Overlaps with the Proposed Development
Apx. Figure 8. 2: Sprat, Mackerel, Plaice and Lemon Sole Spawning and Nursery Grounds and Overlaps with the Proposed Development
Apx. Figure 8. 3: Herring and Sandeel Spawning and Nursery Grounds and Overlaps with the Proposed Development