David V. auteur aut IRD Minart C. auteur aut IRD Mouget A. auteur aut IRD Perrot Yannick auteur aut IRD Thiriet P. auteur aut IRD Feunten E. auteur aut IRD Cheminée A. auteur aut IRD Le Goff L. auteur aut IRD Acou A. auteur aut IRD Brehmer Patrice auteur aut IRD text conferencePaper eng text/pdf reformatted digital access One challenge of acoustic observations of marine organisms is the identification of species, par-ticularly in shallow waters where high diversity occurs. We deployed combining split-beam EK80 (70, 120 and 200 kHz) and M3 multibeam (500 kHz) echosounders to detect monospecific fish shoals in coastal shallow waters (5-60 m). Innovative protocols for the specific allocation were tested, using (i) scuba divers census on fish shoals and (ii) towed scuba diver. Stereoscopic video system was also used to assess fish length and abundance and compare with the visual estimations of divers. Several independent replicates of monospecific shoals from 5 fish species were obtained. The combined used of the echosounders allows to have complementary morpho-logic, acoustic and spatial descriptors to correctly discriminate the shoals. In addition, as the stereoscopic system has shown to provide precise measurements of individuals and could over-come the visual diver observations, our results suggest that a system equipped with cameras like a remotely controlled towed instrumentation platform could be used in a near future for ground trust in shallow and clear waters. specialized ATLANTIQUE 040 032 ICES. Working Group of Fisheries Acoustics, Science and Technology (WGFAST), Somone (SEN), 2022/04/25-28 4 54 45-46 Jech M. ed. edt IRD 2022 https://www.documentation.ird.fr/hor/fdi:010089467 [F B010089464] https://www.documentation.ird.fr/hor/fdi:010089467 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2024-03/010089467.pdf IRD - Base Horizon / Pleins textes 2024-02-14 2024-03-01 fdi:010089467 fre