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D ep artm en t of M arin e S cien ces Fisheries Management Laboratory FADIO Fish Aggregating Devices as Instrumented Observatories of Pelagic Ecosystems Key Words: Hydroacoustics, Multibeam Sonars, Instrumented observatories, FADs, Fisheries models Summary of the Project FADIO is a research project funded by the DG Research of the European Union, gathering one American and eight European partners. The main objective of this programme is to improve our know-how for deploying in the future, as "pelagic observatories", new instruments for studying the behaviour and abundance distribution of pelagic communities. In the same way that oceanographers have historically used instrumented buoys to study the physical dynamics of the oceans, these autonomous pelagic observatories will contribute to a reduction in the use of research vessels and represent a new concept in the study of ocean life. The contribution of the Fisheries Management Laboratory to the project is mainly focused on the following research fields: Development of buoys Development of computerised buoys equipped with networked vertical echosounders, omni-directional sonars and hydrophones, which will scan a wide area of the ocean, collecting complex ecological data about the biomass distribution and behaviour around the buoy. The graph in figure 1 describes the future instrumented buoy, indicating its different instruments (and their potential targets). Fig. 1: Full equipped buoy: Hydroacoustic scanning of pelagic communities and satellite transmission of the signal to the control station. Autonomous operation and species recognition Development of “intelligent” software for the autonomous operation of the buoys. Acoustic target identification and species recognition using the SIMRAD multi-frequency EK60 sounder and the horizontal SP90 sonar system. Advanced processing of the acoustic signal will allow the discrimination between plankton and certain fish species presented in the water column as well as the estimation of their size and abundance (Fig. 2). Tracking algorithms Development of intelligent tools for tracking acoustic targets (single or aggregated fish) and studying the swimming behaviour of target species within a full circle at short (0-500 m) and long (500-8000 m) ranges. This will help to understand the dynamic behaviour of the aggregated fish, such as swimming spatio-temporal patterns and associations between and within species (Fig. 3). Long-range omni- directional sonars like the SP90 and LS30 from SIMRAD specially designed for detection of weak and scattered targets will be utilised, providing a 3D image around the buoy.specific performance measures and reference points, in a way that will convey possible consequences of uncertainty (Fig.3). Fig. 2: Fish discrimination and species recognition based on acoustic signal processing. Vertical (above) and horizontal (below) echograms generated by the EK60 echosounder and SP90 sonar correspondingly. Fig. 3: 3D observation of the dynamic behaviour between pray and predator species. Passive and active acoustic signals are simultaneously acquired and analysed by the networked multiple acoustic system (hydrophones, vertical, horizontal and multibeam sonars). Project duration: 39 months (January 2003 – March 2006) Funding authorities: European Commission, Research Directorates General, Total budget: 2 616 793 Co-operating research partners: IRD (France, Co-ordinator), University of Hawaii (USA), Fundacion AZTI (Spain), IFREMER (France), University of Las Palmas (Spain), IMR (Norway), University of the Aegean (Greece), University of Brussels (Belgium) UNIVERSITY OF THE AEGEAN DEPARTMENT OF MARINE SCIENCES