期刊名称:Western Australia. Fisheries Department. Fisheries Research Reports
印刷版ISSN:1035-4549
出版年度:2009
卷号:187
页码:86-86
出版社:Government of Western Australia / Department of Fisheries
摘要:The use of multibeam echosounders in place of single-beam echosounders for future bioacoustic
surveys is warranted by their increased coverage, which can improve acoustic estimates of
biomass and abundance and better characterize spatial distributions of organisms (Gallaudet and de
Moustier, 2002). Multibeam systems generate a swath of single beams across the vessel tracks with
athwartships coverage in excess of 90¡ã (e.g. Reson 8101 generates a swath of 150¡ã, Reson 8125 of
120¡ã and Simrad SM2000 up to 180¡ã) and minimal fore-aft beam angle, thus covering a footprint
width typically between two and eight times the depth of the water, whilst maintaining high
directional accuracy. In view of this particular project, the swath geometry creates the possibility of
surveying an aggregation of fish in a minimal number of transects, removing several assumptions
required with single beam surveys regarding the temporal uniformity of the aggregation.