A partnership between science and industry for a monitoring of anchovy & sardine in the Bay of Biscay: When fishermen are actors of science

Abstract Anchovy and sardine are small pelagic species occupying similar geographic areas in the Bay of Biscay (North-East Atlantic). Their biomass is strongly dependent on recruitment, making the annual assessment of TAC (Total Allowable Catch) a risky strategy due to uncertainty in predicting the magnitude of recruitment. Monitoring these resources more often and throughout their life cycle could allow management strategies to be adjusted based on observations which indicate the level of recruitment. In order to achieve a more frequent monitoring, an innovative data collection strategy involving a partnership between fishermen and scientists, was developed in 2009 and 2010 called “pilot sentinel surveys”. This paper details the partnership, the information such a partnership can provide and how it can be useful for adaptively managing such resources. The method was based on short surveys undertaken by commercial vessels several times per year, in two spatially limited “key areas” known to be potential recruitment habitats. Acoustic surveys and fishing operations enabling biological sampling, were combined in each key area. Only one scientist was on board and an ad hoc sampling strategy was adopted during each survey by the Captain–Scientist team depending on the local conditions. This partnership allowed scientists to benefit from fishermen’s experience and therefore adopt a sampling strategy which was optimized in time and space. The sentinel survey data were complemented with data collected during annual spring acoustic surveys carried out by the research vessel (RV) Thalassa. The RV was accompanied by commercial vessels allowing additional fishing operations and acoustic echo interpretation to be performed. This experiment showed that the sentinel observations in limited areas cannot provide reliable abundance indices, but are adequate to provide significant biological information on the seasonal progress of the life cycle of each species, such as growth, timing of in-coming recruitment and migration pattern. In addition, these “pilot sentinel surveys” significantly improved the mutual understanding between fishermen and scientists.