2011 Scottish Natural Heritage (SNH) Lochs Linnhe, Etive, Leven and Eil broadscale validation benthic camera and grab survey - part A

The purpose of this benthic survey of Lochs Linnhe, Etive, Leven and Eil was to carry out a broadscale validation survey of the multiple MPA search features historically recorded within the survey area and to record new instances of these and assess previously identified Priority Marine Features (PMFs) and record any new instances of PMFs. Surveying in the Linnhe sea lochs system was split into two parts, A and B. Part A (described here) is a coarse grained characterisation of the search feature distribution, carried out by the Scottish Association for Marine Science (SAMS), incorporated remote benthic sampling using a combination of grab and video (DDV and ROV). Part B was chiefly to examine discrete beds of specific PMFs, undertaken by Heriot-Watt University (HWU), using divers to provide detailed survey analyses on targeted high priority features, shore based survey methods and drop-down video. This study aimed to determine whether PMFs and MPA search features were still present at previously documented locations. A remote video and grab survey was conducted by SAMS for SNH between the 3rd and 26th August 2011 to collect detailed biological information on the seabed species and habitat features present. Drop-down video drift tows were undertaken at 181 sites within the Linnhe sea lochs system study area. The images, analysed under SNH contract by SAMS, were used to describe the nature of the seabed in terms of the physical structure and the species assemblages. An ROV survey was undertaken at 23 sites in Loch Linnhe, generally targeting locations where the northern featherstar (Swiftia pallida) had been recorded, and or where the proximity of steep underwater cliffs or pinnacles made deployment of the drop-down video problematic. Quantitative infaunal grab sampling was undertaken at 37 sites and multigrabs at 12 sites in Lochs Linnhe and Eil for marcofauna analysis and PSA. The vessels RV Seol Mara and SV Sir John Murray were used for this survey.