fa002eb792d41da9064dc587a8234400 English dataset NatureScot (HQ Inverness) data_supply@nature.scot pointOfContact 2025-06-04 MEDIN 3.1.2 EPSG Geodetic Parameter Registry 2021-01-06 revision WGS 84 EPSG Geodetic Parameter Registry 2021-01-06 revision OSGB 1936 / British National Grid 2012 Scottish Natural Heritage (SNH) biological analyses of Marine Scotland (MS) Lochs Alsh, Duich, Creran and Fyne benthic camera survey 2013-01-01 publication NS-000199 NatureScot project ID MRSNH01800000028 Marine Recorder The aim of the survey work was to validate historical PMF records of Limaria, Modiolus and maerl beds within search areas located in Loch Alsh, Loch Fyne and Loch Creran, and to obtain an understanding of the distribution of burrowed and deep mud PMF habitats and component species in Loch Duich. An indication of the probable extent and condition of the features was also sought. The main approach to achieve these aims was by use of diving and remote video and grab sampling techniques. The following PMFs were surveyed at the locations and times (Table 1) provided below: • Loch Alsh - Modiolus and Limaria beds • Loch Duich - burrowed mud, deep mud, Pachycerianthus and, in the approaches, Limaria • Otter Spit, Loch Fyne - Limaria and maerl beds • Furnace area, Loch Fyne - Limaria and Modiolus beds • Loch Creran - Limaria beds Scottish Natural Heritage (SNH) Scottish Natural Heritage (SNH), Headquaters Data Manager 01463 725000 data_supply@nature.scot owner NatureScot (HQ Inverness) NatureScot Data Manager data_supply@nature.scot custodian Scottish Natural Heritage (SNH) Scottish Natural Heritage (SNH), Headquaters Data Manager 01463 725000 data_supply@nature.scot originator Esther Hughes Data Archive for Seabed Species and Habitats (DASSH) Data Manager 01752 633102 dassh.enquiries@mba.ac.uk distributor notPlanned Marine Environmental Data and Information Network MEDIN metadata record availability 2025-06-04 revision NDGO0005 NDGO0005 2025-06-04 revision Habitats and biotopes Species distribution GEMET - INSPIRE themes, version 1.0 2021-09-28 revision Habitat characterisation Habitat extent Macroalgae and seagrass taxonomy-related counts Zoobenthos taxonomic abundance Zoobenthos taxonomy-related counts SeaDataNet Parameter Discovery Vocabulary 2021-09-28 revision otherRestrictions no restrictions to public access otherRestrictions Not for navigational use; SNH copyright data which is available for re-use under government licence terms: http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/ English 8-bit variable size UCS Transfer Format, based on ISO/IEC 10646 biota environment oceans -5.7925415039063 -5.4299926757812 55.70274201067 56.335192174035 SeaVox salt and freshwater body gazetteer 2021-01-06 creation Inner Seas off the West Coast of Scotland Charting Progress 2 Sea Areas 2021-01-06 creation Minches and Western Scotland 2012-08-20 2012-09-23 SeaVoX Vertical Co-ordinate Coverages 2021-01-06 revision circalittoral SeaVoX Vertical Co-ordinate Coverages 2021-01-06 revision infralittoral SeaVoX Vertical Co-ordinate Coverages 2021-01-06 revision littoral Database Marine Recorder Image Movie dataset Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 publication 2.1 Loch Alsh and Loch Duich The objective was is to survey three Modiolus beds, a mixed Modiolus/Limaria bed and seven other possible Limaria beds. 2.1.1 String Rock Modiolus bed Work initially concentrated on this bed as it was considered to be probably the largest, and the decline in Modiolus density recorded in 2004 here was responsible for the Duich, Long and Alsh SAC being deemed to be in an unfavourable condition. Thus, additional site condition monitoring data were obtained here. Cross-strung 0.25 m2 quadrats were used to assess percentage cover of live Modiolus at the 14 sites examined in 1999 and 2004 (Figure 1), ten of which were also studied in 2007. Eleven of these were located at 20 m intervals along a 200 m groundline. The groundline was relaid but to enhance the accuracy of site relocation, stations were relocated using the recorded 1999 depths for each station, if necessary in combination with use of the calibrated groundline. The number of string intersection hits (maximum 16) were recorded using 10 replicate quadrats at each site, also recording the presence of dead Modiolus, depth, substrate and brittlestar cover. To further examine possible recovery of the bed, Modiolus samples were taken for population structure analysis at station 1, where a similar study was carried out in 1999 (Mair et al.., 2000). 5 replicate quadrats were cleared of all shell and stone material and the material returned to the surface for measurement of length, breadth and height of Modiolus specimens using vernier callipers. The residue material was retained for future inspection and measurement of spat in the laboratory. As only 50 Modiolus were collected a further clearance of material was made to bring the total Modiolus measured to around 100. Measured specimens were returned live to the seabed at the collection site. An MNCR phase 2 survey, including the collection of four replicate Modiolus clump samples for analysis of the associated fauna, was also carried out at station 1 (HM01, Figure 1), accompanied by video and still photography to characterise the habitat and community. An indication of extent of this and other Modiolus beds (as well as Limaria) was carried out by recording various parameters at a number of stations along diver drift or swum transects (Figure 1). See Limaria section for methodology. 2.1.2 Other Modiolus beds Diver transects were also carried out at the sites of historical records of Modiolus beds under the Skye Bridge (2 sites in Scott, 1991) and NE Eileanan Dubha (Connor, 1989) (Figure 1). 2.1.3 Limaria beds Initially, areas containing historical records of Limaria beds were examined by drift or swum diver transects, but it became apparent that Limaria was far more widely distributed than previously recorded and so the search area was extended to cover much of the seabed from west of the Skye Bridge to east of Eileanan Dubha. In total 75 stations were worked by divers along transects recording the following data for assessment of both Limaria and Modiolus distribution and condition (Figure 1): • % cover by Limaria nest material • thickness of Limaria nest • presence of discrete nests • Limaria hians seen/not seen • substrate • depth • % algal turf cover • kelp species and SACFOR abundance • brittlestar abundance (SACFOR) • brief notes on community characteristics • Modiolus SACFOR abundance Station positions were fixed by the surface vessel following diver signalling using the surface marker buoy. MNCR phase 2 surveys were carried out with video and still imagery at two sites, a Limaria bed (FS01) and a mixed Modiolus/Limaria bed (HM02) (Figure 1), with the collection of four replicate cores (10.3 cm diameter to a depth of c.20 cm) for infaunal analysis and one core for PSA at FS01 and four replicate Modiolus clump samples at HM02. Core material was screened with a 0.5 mm sieve. 2.1.4 Loch Duich 36 sites were surveyed by dropdown video (Figure 2), which included 31 in Loch Duich and four to assess the presence of Limaria in Loch Alsh where predicted by the broadscale survey of Entec (Johnston et al., 1997). At each site video footage was collected along a run generally of around 3 - 8 minutes with the following parameters being recorded on a pro forma: • site • date • surveyors • time in and out • position in and out • depth in and out • substrate description • biota description • ID code for miniDV • target PMF • target depth range (chart datum) Single 0.1 m2 van Veen grab samples were taken at 10 stations with a c.150 ml subsample taken for particle size analysis and the remaining material sieved on a 1 mm mesh. 2.2 Loch Fyne The Otter Spit area was surveyed by diver transects with the same data recorded as for Loch Alsh at 45 stations (Figure 3), but with the addition of % live and % dead maerl cover. Validation dives were also carries out for Limaria at The Tea Rooms in the Furnace area of Loch Fyne, and for a Modiolus bed west of Kilbride Island (Figure 4). An MNCR phase 2 survey was carried out in a representative area of the Limaria bed, with collection of still and video imagery and four replicate core samples for infaunal analysis and one core for particle size analysis (Figure 3). The faunal cores were screened using a 0.5 mm mesh. 2.3 Loch Creran In view of the smaller anticipated size of the Loch Creran Limaria beds and the strong current conditions, the above approach for data collection along transects was modified. Rapid position fixing at stations along transects was achieved by use of a towed surface GPS logger, attached to the SMB, with station positions obtained by the diver recording the time, which was synchronised with GPS time (Figures 5, 6). An algorithm was developed to obtain site positions based on the GPS surface fix and the direction and distance of the GPS receiver layback, calculated from diver records of depth, SMB line length and SMB line direction. Otherwise, surveys of the distribution of Limaria beds at Shian and Creagan Narrows and a possible bed in the mouth of Loch Creran were carried out in a similar manner to that at Otter Spit (excluding the maerl component). MNCR phase 2 surveys were carried out on the Limaria bed at Shian (FS03) and Creagan (FS04) with associated imagery and core collection (Figures 5, 6).