Acoustic selectivity to improve biomass estimation and discriminate non-target species

Acoustics applied to the knowledge of fishery resources: ECHOSOUNDS of DCPDs

By using AZTI’s DCPDs Echosounders it is possible to achieve:

• Improve the estimate of biomass in tonnes for tuna and non-target species from the sonar beacons.
• Discriminate small tunas from the sonar beacons.
• Discriminate non-target species from the sonar beacons.

DCPD echosounders allow improved biomass estimation in tonnes for tuna and non-target species from the sonar beacons.

Benefits

• To know the biomass associated with a floating object in a more precise way, both for fishing and for its study.
• To know the groups of species associated with a floating object, both for more selective fishing and for its study.

Fields of application

• Buoy marketing companies.
• Fishing sector.
• Scientific community.
• Public administrations and official bodies wishing to avoid fishing for non-target species in the tropical tuna purse seine fleet.
  
  AZTI is the only institute in the world that works with the sonar beacons used by the fishing industry to geolocate floating objects.

Proven expertise

• AZTI is the only institute in the world that works with the sonar beacons used by the fishing industry to geolocate floating objects.
• More than 10 years of research on species associated with free-floating objects, using acoustic and tagging techniques.
• Multidisciplinary team, specialised in fishing technology, eco-ethology of species of interest and underwater acoustics.
• Members of expert committees on acoustics (ICES Working Group on Acoustics) and members of the ISSF by-catch scientific committee.
• Specific technologies available:
  • Simrad 38, 120 and 200 kHz scientific sounders
  • Acoustic tag listening stations
  • Environmental satellite maps (altimetry, temperature, chlorophyll, etc.)

Success stories

• FADIO Project, study of FADs (floating objects) as observatories of the pelagic environment: acoustic study prior to species recognition.
• Project Selectun, study of the behaviour and discrimination of tuna from sonar beacons.
• EU MADE project: improvement of algorithms for estimating the biomass of species associated with floating objects and study of aggregations under the free floating objects (behaviour in relation to environmental parameters).
• A doctoral thesis, on obtaining abundance indices from sonar beacons and for the study of tuna dynamics in relation to environmental variables.
• Two scientific publications (Lopez et al 2013 submitted) on the use of sonar beacons and the improvement of biomass estimates.