On the development of acoustic descriptors for semi-demersal fish identification to support monitoring stocks

• DOI: 10.1093/icesjms/fsaa232
• Publication Date: 2020-11-24T23:38:19Z
• Authors: Réka Domokos
• Keywords: Target strength; Stock assessment; Demersal zone; Fish stock; Demersal fish; Fish measurement; Stock (firearms)

Abstract Despite worldwide economic importance of lutjanid snappers, there are critical data gaps hindering accurate abundance estimates these species, thereby impeding stock management efforts. Development an active acoustics method could fill many gaps, significantly benefiting assessment snapper species that form typically mixed-species assemblages in non-trawlable regions. These methods well suited for resource surveys but require the ability to derive size from target strength (TS) and separation echoes within stock. This work evaluates feasibility surveying a Hawaiian bottomfish stock, referred as Deep-7 complex, consisting six snappers single grouper. Acoustic backscatter complementary methodologies were used model TS develop acoustic descriptors such aggregation shape, size, density, individual swimming pattern, distance bottom, bottom depth species. Paired observations situ fork length (FL) gave estimated bulk relationship 23.01·log10(FL)–72.18. The success 25 accuracy tests indicates effectiveness developed echo allocation parameters. Preliminary results imply be successfully monitor with broader applicability upon adapting methodology other