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This document is the final version of the report of the MedSudMed Oceanographic Survey carried out in Libyan waters from 12 to 24 August 2006 on board of the R/V Urania. The document presents also the results of the processing of the data collected during the survey. The survey was carried out under the cooperative framework promoted by the FAO Project MedSudMed (Assessment and Monitoring of the Fishery Resources and the Ecosystems in the Straits of Sicily). The main objective of the survey was to collect information on areas of concentration of eggs and larvae of small pelagic fish species and relate them to the mesoscale physical aspects characterizing the area. During the survey, advantage was also taken to collect sediments and water samples to update and/or complement existing information on bottom types and study the chemical-physical properties of the water masses. The results were expected to complement information available in the rest of the MedSudMed area, where hypothesis were drawn on the transport and retention processes of small pelagic fish eggs. The main target species for the ichthyoplankton study were anchovy (Engraulis encrasicolus) and round sardine (Sardinella aurita). An overall description of the sampling scheme, of the area explored and of the methods adopted is provided. The distribution and abundance of eggs and larvae of E. encrasicolus and S. aurita in Libyan waters is described, as well as the composition and abundance of phytoplankton. The main oceanographic characteristics, including water mass circulation, in the western Libyan waters are also illustrated. A description of the trophic status of the waters is also provided taking into account nutrients and suspended matter. A description of the content of trace elements and nutrients in the water column complete the information provided in this report.