Report of the ICES Study Group on Acoustic Seabed Classification (SGASC)

The second meeting of the ICES Study Group on Acoustic Seabed Classification (SGASC) was held at the Sea Fisheries Institute (MIR), Gdynia, Poland 18–19 April 2004. A total of twenty nine delegates and observers participated in the two day meeting, representing eleven countries and five industry groups. The meeting was chaired by John Anderson (Canada). Since the inaugural meeting in 2003, members of the Study Group have been working by correspondence to develop a detailed outline for an ICES Cooperative Research Report (CRR) on acoustic seabed classification. Lead authors were identified to develop the report chapters adopted last year and to recruit further experts as required in order to meet the terms of reference originally identified for the Study Group. The Study Group reviewed presentations by lead authors and developed timelines over the next year for the writing and editing of the CRR on Acoustic Seabed Classification. The Study Group will meet next year, 2005, in association the Working Group on Fisheries Acoustics and Science Technology (WGFAST) to review and finalize the CRR. The Study Group now has a direct contact with the Working Group on Marine Habitat Mapping (WGMHM) through Dr. R. Coggan (United Kingdom).Ecosystem based management of marine resources will require that natural regions be identified and mapped over a range of hierarchically nested scales. Acoustics is regarded as the remote sensing tool that will provide the basis for classifying and mapping ocean resources. Existing acoustic systems can measure seabed sediment properties and bedform morphology from scales of boulders (< 1 m2) to the scale of shelves (> 100,000 m2). Acoustic metrics relating to seabed habitats can be regarded as proxy measures, or surrogates, of seabed habitats that can be collected in a cost effective manner continuously across broad scales. Acoustic systems considered by the Study Group include vertical incidence single beam echosounders (SBES), oblique incident sidescan sonar systems (SSS) and multibeam echosounder systems (MBES).The aim of the ICES Cooperative Research Report is to review the state-of-the-art in acoustic seabed classification (ASC). The report will provide an overview of the major issues and applications in this field and a comprehensive review of the technologies and techniques used to investigate these. Acoustic technology and classification science is rapidly evolving to meet the needs of nations to manage and conserve coastal resources. As such, the ICES Cooperative Research Report must be seen as representing a snap-shot of the discipline at this point in time. While we anticipate that new developments will occur regularly and that this subject must be revisited in the future, we hope that the CRR will form a basis of our current understand and will provide guidelines for the coordination of scientific developments in this field.