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    The purpose of the current study was to initiate site condition monitoring of the reefs of Loch Creran. This was done to establish a baseline biological data set that would facilitate the assessment of the condition of the reef habitats in the future and to allow a judgement to be formed on the current condition of these habitats. The approach taken to achieve these objectives was to assess the extent and distribution of serpulid reefs from observations by diver along 110 transects around the loch. Detailed studies were also performed at four of the major serpulid reef sites in the loch. Here, distribution was examined with sidescan sonar, reef density by video and the community of organisms associated with the habitat by diver survey of the reefs themselves and of the surrounding sediment. The distribution and abundance of Modiolus was examined along seven relocatable transects and, at one of the major mussel beds, the size structure of the population and associated community surveyed. Subtidal rocky reefs were surveyed by diver along relocatable transects at three sites.

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    The aim of the survey was to map the seabed environment around North Rona. The survey will form the baseline for future management of the area to determine the scope and nature of any appropriate assessment. The survey area encompasses the seabed all around North Rona. In order to record and characterise the habitats around North Rona, Seastar Survey Ltd. undertook an acoustic and a ground-truthing survey (video/still photography survey) in 2009. The aim of the acoustic element of the survey was to identify different backscatter returns and describe as well as delineate the extent of the various seabed habitat types occurring around North Rona. A digital sidescan sonar mosaic, in conjunction with single beam echo sounder derived bathymetry, provided the initial broadview to map the substrata present throughout the survey area as well as allowing the identification of any features of interest. The aim of the ground-truthing element of the survey was to provide a description of the richness and diversity of the habitats on both rocky reef and the softer sediments. The biotope distribution and species composition was developed through interpretation of drop-down video footage and digital still photography, taken after evaluation of the sidescan mosaic. The results of all elements of the survey were used to create a Geographical Information System (GIS) which enabled a high level of processing, interpretation and display of the sidescan sonar mosaic, bathymetry, substrata types, biotopes and the digital photography.

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    The Sound of Harris is a topographically complex marine area situated between North Uist and Harris in the Outer Hebrides. Very little is known of the marine biota of the area but it is likely to be largely unmodified by anthropogenic influences. An increased knowledge of the marine biotope distribution in the Sound of Harris is desirable in order to assess the potential impacts of any proposed future developments in the area. Specifically, proposals to build access causeways linking Hebridean Islands are increasingly under consideration. Such developments have the potential to radically modify environmental conditions in neighbouring marine habitats. This study utilised satellite imagery, underwater acoustic sensing techniques and biological ground surveys to develop a biotope distribution map of the area and relate this distribution to prevailing environmental conditions.

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    A broadscale benthic survey of Loch Creran was carried out in 1998-1999. The primary objective of the study was to map the sublittoral habitats and delimit biotopes. AGDS was used, ground-truthed by grab sampling, ROV, diver video and stills photography.

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    Field survey of the intertidal and subtidal areas of the Solway Firth (north shore). Intertidal using shore survey and SACFOR abundance scale, subtidal using RoxAnn, ground-truthed with ROV and 0.1m Van Veen grab.

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    This project attempts to map the broadscale biotopes and habitats of the rocky reef sites west of the Outer Hebrides through integrating multibeam echosounder data, acoustic ground discrimination system (AGDS) data, underwater video/camera surveys and grab data, facilitated through the use of GIS. Where possible, biotopes have been resolved and classified using the National Marine Habitat Classification for Britain and Ireland (Connor et al., 2004).

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    Envision Mapping Ltd was contracted to undertake a survey of the Moray Firth cSAC within the 30m contour. The purpose was to map the main sediment features and biota using acoustic remote sensing techniques combined with grab and video sampling. A RoxAnn? acoustic ground discrimination system was used in conjunction with a GeoSwath? interferometric swath bathymetric system. The survey was comprehensive (100% cover with the swath system or a minimum track spacing of 80m) over priority areas but incomplete over areas outside these priority areas. The biotopes were classified using the most recent Marine Habitat Classification (Connor et al. 2004) using a combination of multivariate analysis and video analysis and matching the characterising species to the classification system.

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    Envision Mapping Ltd was contracted to undertake a survey of the Moray Firth cSAC within the 30m contour. The purpose was to map the main sediment features and biota using acoustic remote sensing techniques combined with grab and video sampling. A RoxAnn? acoustic ground discrimination system was used in conjunction with a GeoSwath? interferometric swath bathymetric system. The survey was comprehensive (100% cover with the swath system or a minimum track spacing of 80m) over priority areas but incomplete over areas outside these priority areas. The biotopes were classified using the most recent Marine Habitat Classification (Connor et al. 2004) using a combination of multivariate analysis and video analysis and matching the characterising species to the classification system.

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    Envision Mapping was sub-contracted by Heriot Watt University for Scottish Natural Heritage (SNH) to undertake broad scale subtidal biotope mapping of Sullom Voe cSAC. Sullom Voe in the Shetland Isles is the most northerly site in the UK to be selected as a representative of large shallow inlets and bays, and within the site series it is the only Scottish example of a ria (known locally as a ?voe?). The boreal-arctic (northern) species-rich communities of Sullom Voe are restricted to Shetland voes and are not represented elsewhere in the SAC series. The purpose was to map the main features and biota using acoustic remote sensing techniques combined with grab and video sampling.

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    Survey of the intertidal and subtidal zones of the Treshnish Isles cSAC to provide a broad scale biotope distribution map for the area. This dataset is a map of predicted subtidal lifeforms for the area surrounding the Treshnish Isles.