Ecological basis to embrace temporal assessment and spatial management of european hake in the Western Mediterranean

Abstract

Beyond restrictions in fishing effort to reverse the current overexploitation of European hake in the Mediterranean Sea, the challenge according to the Mid-term strategy (2017–2020) is to improve the ecological basis of the assessment procedures in relation to: i) the critical ecological processes, ii) the information available and the capacity to annually retrieve it, and iii) the life stage/s that will frame the main management measures. However, one of the main limitations to respond to this challenge is that, for most geographic subareas, quantitative information is only available for recruits and juveniles, while considerably limited for adults. Here, we used two case studies of the Western Mediterranean (the Spanish Iberian coast and the Alboran Sea) to synthesize the increasing available knowledge on capital ecological processes in recruits and juveniles susceptible to be implemented in the assessment and management procedures. Indeed, spatial management of hake juveniles is becoming an effective measure to be broadly implemented in the Mediterranean. However, it is currently unconnected from the population dynamics and the quantitative assessment. Here, we reviewed information on the structural complexity of populations, oceanic and demographic connectivity, hydroclimate and life history influence on survival, and drivers of the spatial-temporal distribution. These processes can help to improve the knowledge about the stock-recruitment relationships, natural mortality vectors, or habitat-based standardization of CPUEs. We discuss that an effective implementation of ecological knowledge can help to embrace quantitative periodic assessment and spatial management in an operational way, providing a more holistic and ecosystem-based approach of hake.