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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