Solway Firth SAC / Allonby Bay pMCZ Rocky Scar Grounds and Annex I Reef Drop-down Video Survey: Final Report.
This report presented the result of drop-down video survey of the Allonby Bay pMCZ and Solway Firth SAC survey areas which aimed to assess the extent and distribution of subtidal rocky scar ground communities and Annex I reef features and was successfully completed in three phases in 2014-15. A total of 62 transects were attempted throughout the survey areas sing Seastar Survey's own HD Freshwater Lens Camera System (FLCS), with a total of 269 discrete video clips achieved. In the Allonby Bay pMCZ the seabed was found to be dominated by gravelly mixed sediments with SS.SMx (sublittoral mixed sediment), though coarse and sandy sediments (SS.SCS, sublittoral coarse sediment and SS.SSa, sublittoral sands and muddy sands, respectively) as the most commonly identified broad habitat type. Communities on mixed sediments were more species rich, being characterised by hydroids, the bryozoan Alcyonidium diaphanum and ascidians. The Solway Firth SAC survey area was found to be dominated by sands and muddy sands SS.SSa (sublittoral sands and muddy sands) though coarse and mixed sediments (SS.SCS, sublittoral coarse sediment and SS.SMx, sublittoral mixed sediment respectively) as the most commonly identified broad habitat type. The soft sediments observed were generally species poor, with only mobile macrofauna such as swimming crabs, shrimp and seastars such as Asterias rubens recorded. Areas of the reef forming polychaete Sabellaria alveolata were observed in Allonby Bay, whilst a single transect in the inshore of the Solway Firth SAC was found to be dominated by the mussel Mytilus edulis.