2014-15 NE Solway Firth SAC/ Allonby Bay pMCZ Rocky Scar Grounds & Annex I Reef Drop-Video Survey

notPlanned

"The Solway Firth is a large, complex estuary and one of the more important and least industrialised estuarine areas in Europe (JNCC 2015a). The Solway Firth Special Area of Conservation (SAC) was designated under the Natura 2000 programme due to the following Annex I qualifying features; estuaries; sandbanks which are slightly covered by seawater all the time; mudflats and sandflats not covered by seawater at low tide; Atlantic salt meadows; and Salicornia and other annuals colonising mud and sand. In addition, present as a qualifying features, but not a primary reason for selection, is the Annex I habitat reefs.Allonby Bay pMCZ extends over 39 km2 of Cumbrias coastline up to 5.5 km offshore, encompassing the entirety of Allonby Bay. The pMCZ is proposed in order to provide protection to a number of features of conservation interest including blue mussel beds, honeycomb worm (Sabellaria alveolatareefs and peat and clay exposures as well as a number of broadscale habitats. In order to inform site condition monitoring, Seastar Survey Ltd. were contracted by Natural England to undertake a drop-down camera survey of both the Solway Firth SAC and the Allonby Bay pMCZ in order to define the distribution and extent of any subtidal rocky scar grounds communities present. Main FindingsA total of 62 transects were attempted throughout the survey areas using Seastar Surveys own HD Freshwater Lens Camera System (FLCS), with a total of 269 discrete video clips achieved. the Allonby Bay pMCZ the seabed was found to be dominated by gravelly mixed sediments, while the Solway Firth survey area was characterised by sands and muddy sands.sediments were generally species poor, while coarse sediments - usually consisting of cobbles and pebbles - were generally characterised by encrusting fauna, sparse hydroids, Alcyonidium diaphanum, ascidians and highly mobile epifauna.scar ground was observed on 7 of the 12 achieved transects in Allonby Bay, and 3 transects in the Solway Firth SAC survey area, though areas of sparse pebbles on soft sediment were more widespread.of rocky scar ground have been generated by extending a 300 m radius from any point source at which the seabed was shown to be composed of greater than 10 % cobbles.of rocky scar ground were concentrated primarily west of Dubmill Point and around Dubmill Scar), and in the centre and south of Allonby Bay. In contrast to previous surveys, no rocky scar ground was observed in the west of the Allonby Bay pMCZ in the vicinity of Maryport Roads.on areas of rocky scar ground was relatively sparse, featuring robust, scour-tolerant species such as hydroids, A. diaphanum, encrusting sponge and the ascidian Dendrodoa grossularia. of Sabellaria alveolata were observed in Allonby Bay, and a Mytilus edulis bed was observed in the Solway Firth survey area."