Abstract
Despite the importance of the recruitment process for small pelagic fish and the high economic importance of European sardine (Sardina pilchardus, Walbaum 1792) in the Mediterranean Sea, knowledge on the distribution and environmental characteristics of its nursery grounds is very limited. In the present study, we used pelagic trawl data collected during 1995–2006 to explore the spatial distribution of sardine juveniles in the Aegean Sea in early summer. Based on sardine abundance per length class, a cluster analysis was initially used to define hauls dominated by juveniles. In a subsequent step, Discriminant Function Analysis (DFA) was applied to discriminate stations with high relative abundance of juveniles using satellite environmental data and bottom depth. The parameters contributing mostly to the discrimination of juvenile grounds were sea level anomaly, photosynthetically active radiation, sea surface temperature, chlorophyll-α and bottom depth. The classification functions of DFA were finally used to post classify unsampled areas in the Greek Seas and the Mediterranean Sea in order to map grounds that meet characteristic environmental conditions for young sardine. Such areas were mostly located inshore, in semi-closed productive areas and often in proximity to river mouths, a pattern that is generally supported by existing information.
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Acknowledgements
The present work was based on data collected during surveys for the “Greek National Fisheries Data Collection Program” (Hellenic Ministry of Rural Development and Food) and was co-funded by the Commission of the European Communities through the projects “Environmental Approach to Essential Fish Habitat Designation” (FP6-22466) and “SARDONE: Improving Assessment and Management of Small Pelagic Species in the Mediterranean” (FP6-44294). We would like to thank the captain and the crew of R/V Philia for their invaluable help.
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Essential Fish Habitat Mapping in the Mediterranean
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Tsagarakis, K., Machias, A., Somarakis, S. et al. Habitat discrimination of juvenile sardines in the Aegean Sea using remotely sensed environmental data. Hydrobiologia 612, 215–223 (2008). https://doi.org/10.1007/s10750-008-9500-3
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DOI: https://doi.org/10.1007/s10750-008-9500-3