Assessment of the appropriateness of areas closed to protect priority marine features from scallop dredging around Shetland.

• Main Authors: Shelmerdine, Richard L., Robinson, Martin, Johnson, Arthur, Leslie, Beth, Stone, Daniel, Tait, Leslie
• Format: Book
• Language: English
• Published: NAFC Marine Centre 2013
• Subjects: Modiolus modiolus
• Online Access: https://pure.uhi.ac.uk/en/publications/b8a7abf5-f18c-4302-8087-47b77d1fda55; https://pureadmin.uhi.ac.uk/ws/files/1438918/Shelmerdine_et_al_2013_Report_on_areas_closed_to_scallop_dredging.pdf

Horse mussel (Modiolus modiolus) and maerl beds are ‘priority’ habitats that can be threatened by human activity and as such require conservation under the UK Biodiversity Action Plan (UK BAP). During 2010 the Shetland Shellfish Management Organisation (SSMO), the body responsible for the management of all shellfish stocks within six nautical miles of Shetland, proposed to voluntarily close 24 areas to scallop dredging vessels in order to help conserve these priority habitats. Initially, the boundary of each closed area was defined from data extracted primarily from the Shetland Marine Spatial Plan but also through consultation with local maritime users. Some data were of limited quality, extent, or based on non-validated reports several decades old. In several cases fishermen actively involved in the development of the closed areas questioned whether the priority feature was present in the area at all, based on their local knowledge. Despite such reservations, the science-industry partnership involved agreed to adopt an iterative, precautionary approach whereby areas would be closed pending detailed survey and assessment, and the legalisation of the voluntary closed areas came into force in 2011. The primary aim of this report was to define the effectiveness of the current closed areas based on up-to-date, high resolution survey data so that the SSMO can validate and refine its spatial management plan. Closed areas to scallop dredging are widely distributed around Shetland, amounting to just under 26 km2 of sea surface area. The areas vary in size from 0.003 km2 to 14.6 km2, the largest accounting for 56.6% of the total area closed around Shetland. This variation is primarily due to the type of externally sourced data (i.e. point data or predicted species bed) used to originally define the extent of the feature. Historically, predicted species beds had been derived from a number of sources and various agencies from a combination of point data and localised bathymetry information. The current study surveyed ...