Abstract
Within six nautical miles of the Shetland coast, scallop dredge fishing is managed by the Shetland Shellfish Management Organisation (SSMO). Management measures, including a spatial management plan, prohibit dredge fishing in designated areas with confirmed or suspected ‘sensitive seabed habitats’ (e.g. maerl beds, horse mussel beds, sea grass). The fishery gained Marine Stewardship Council (MSC) accreditation in 2012. Evolving MSC standards emphasise assessing the impacts of fishing activity on commonly encountered habitats. The aim of this work is to provide detailed information on habitats encountered by the Shetland scallop dredge fishery within 6nm of shore to better understand the interactions between the fishery and the environment in which it operates through the creation of habitat encounter maps, a sensitivity map, and corresponding confidences.
Scallop fishery dredge locations were previously mapped by UHI Shetland for the SSMO. Biotope data was sourced from the Shetland Islands dominant marine biotope map produced through the use of distribution models. Habitat sensitivity information was derived from the Feature Activity Sensitivity Tool (FeAST) and Marine Life Information Network (MarLIN) portals. FeAST facilitated the assessment of impacts on conservationally important marine features, while MarLIN provided a comprehensive overview of marine evidence and sensitivity assessments for key species and habitats. Pressures associated with scallop dredging were identified, and each biotope was assigned a sensitivity level based on available information categorised as 'High', 'Medium', or 'Low'. Biotope-Fisheries Encounter maps were created by overlaying scallop fisheries data onto the Shetland Islands dominant marine biotope map, allowing for sensitivity analysis of habitats encountered by fisheries.
The biotope-fisheries encounter maps provided a comprehensive overview, highlighting locations of interest. The encountered biotopes showcased considerable variability. The study showed that of the 28 biotopes recorded within Shetland waters, six biotopes exhibited no interactions with the fishery grounds, potentially indicating unsuitability for dredging. Two biotopes (‘offshore circalittoral mixed sediment’ and ‘circalittoral fine sand’), both labelled ‘low’ sensitivity, accounted for the majority of encounters, totalling 49.88%.
Sensitivity encounter analysis highlighted the fishery’s prominence in ‘low’ sensitivity habitats (74.67%), with minimal interactions in ‘high’ sensitivity areas (1.61%), which were concentrated south-east of Whalsay and Bressay. The remaining 23.62% of encounters involve 'medium' sensitivity habitats. Understanding the ecological significance of these interactions is crucial for developing targeted management strategies to minimise potential adverse effects.
It is noteworthy that not all 'high' sensitivity biotopes are PMFs, and conversely, some non-PMF biotopes exhibit 'high' sensitivity to scallop dredging. The use of distribution models and fishery encounters provides a benchmark for future spatial management. While acknowledging potential future improvements in data inputs and model outputs, the report offers vital insights for informed, sustainable fishery management that balances economic interests with environmental considerations.
Scallop fishery dredge locations were previously mapped by UHI Shetland for the SSMO. Biotope data was sourced from the Shetland Islands dominant marine biotope map produced through the use of distribution models. Habitat sensitivity information was derived from the Feature Activity Sensitivity Tool (FeAST) and Marine Life Information Network (MarLIN) portals. FeAST facilitated the assessment of impacts on conservationally important marine features, while MarLIN provided a comprehensive overview of marine evidence and sensitivity assessments for key species and habitats. Pressures associated with scallop dredging were identified, and each biotope was assigned a sensitivity level based on available information categorised as 'High', 'Medium', or 'Low'. Biotope-Fisheries Encounter maps were created by overlaying scallop fisheries data onto the Shetland Islands dominant marine biotope map, allowing for sensitivity analysis of habitats encountered by fisheries.
The biotope-fisheries encounter maps provided a comprehensive overview, highlighting locations of interest. The encountered biotopes showcased considerable variability. The study showed that of the 28 biotopes recorded within Shetland waters, six biotopes exhibited no interactions with the fishery grounds, potentially indicating unsuitability for dredging. Two biotopes (‘offshore circalittoral mixed sediment’ and ‘circalittoral fine sand’), both labelled ‘low’ sensitivity, accounted for the majority of encounters, totalling 49.88%.
Sensitivity encounter analysis highlighted the fishery’s prominence in ‘low’ sensitivity habitats (74.67%), with minimal interactions in ‘high’ sensitivity areas (1.61%), which were concentrated south-east of Whalsay and Bressay. The remaining 23.62% of encounters involve 'medium' sensitivity habitats. Understanding the ecological significance of these interactions is crucial for developing targeted management strategies to minimise potential adverse effects.
It is noteworthy that not all 'high' sensitivity biotopes are PMFs, and conversely, some non-PMF biotopes exhibit 'high' sensitivity to scallop dredging. The use of distribution models and fishery encounters provides a benchmark for future spatial management. While acknowledging potential future improvements in data inputs and model outputs, the report offers vital insights for informed, sustainable fishery management that balances economic interests with environmental considerations.
| Original language | English |
|---|---|
| Number of pages | 53 |
| DOIs | |
| Publication status | Published - 30 Jan 2024 |