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An Echo-Integration survey on the equator made during he GARP Atlantic Tropical Experiment indicated an important biomass in the layer 0/100m. The changes of that biomass have been connected to hydrological conditions. Measurements of target strength have been made, and the biggest schools have been measured.

This paper presents a method that permits to inter standardize three sources of acoustic data delivered by several different acoustic devices in order to monitor the behaviour of pelagic fish schools. An omnidirectional multi-beam sonar (32 beams/23.75 kHz), a lateral multi-beam scanning sonar (60 beams/455 kHz) onboard a research vessel and a portable echo sounder (129 kHz) onboard a small craft are used. The method is presented in two parts. The first deals with the multi-beam acoustic sonar (lateral and omnidirectional) and the second with the portable echo sounder and the omnidirectional sonar. The same schools using the portable echo sounder and the omnidirectional sonar are recorded. The same experiment with the lateral sonar and the omnidirectional one is done. The echo characteristics of the omnidirectional sonar data are compared with the two other sources of acoustic data. The preliminary "behavioural database" of fish schools is obtained by gathering the information from the three complementary devices. For each school the depth, size, two and three dimension morphology, acoustic characteristics and the swimming behaviour characteristics (swimming speed and pattern) are measured. The potential output of such database for fisheries research is discussed through preliminary results.