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Climatological characteristics of water masses and circulation in the south–central Mediterranean Sea (Straits of Sicily and surrounding areas) have been estimated and compared with previous knowledge by using a model-based approach. The climatological fields have been calculated in the form of monthly and seasonal averages from the output of a numerical model run over a period of five years (4th January 2000 – 27th December 2004). The numerical model is a 3D primitive equation, mesoscale resolving regional ocean model based on POM (Princeton Ocean Model). The support of literature and satellite data proved to be fundamental to correctly interpret model results and vice-versa. Results show distribution of the main water masses comparable to the literature and confirm the hypothesis of a counter phase behaviour for the two main branches of the Algerian Current entering in the Straits of Sicily, the ATC (Atlantic Tunisian Current) stronger in winter and the AIS (Atlantic Ionian Stream) stronger during summer. The model results offer a detailed description in time and space of the hydrological characteristics of this very dynamic part of the Mediterranean and offer a basis for linkages to ecological and biological implications.

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The FAO–MedSudMed Regional Project has promoted research on the improvement of knowledge on fishery ecosystems, with a view to the sustainable management of living marine resources in the central Mediterranean (Straits of Sicily). A pilot study focused on the waters around the Maltese Islands (GSA 15), with the aim of providing a comprehensive overview of the spatial distribution of the different life stages of exploitable demersal fishes in relation to the type and distribution of fishing, as well as to the oceanographic factors characteristic of the area of study. Critical zones for their role in the ecology of the main demersal fishery target species were investigated using species abundance data disaggregated by life stage. Spatial analysis and the application of GIS techniques allowed the identification of preferred habitats (e.g. nursery, feeding and spawning areas) for Merluccius merluccius, Mullus barbatus, Parapenaeus longirostris, Raja clavata and Raja miraletus. The impact of fishing on these species was assessed, particularly in terms of fish assemblages. The transport paths of early life stages were also hypothesized on the basis of oceanographic factors typical of the area. The results revealed that the spatial distribution of the main fishery resources overlaps the limits of the current GSAs. The analysis of oceanographic factors showed that some fishery resources are sustained by young individuals transported from adjacent GSAs. The results also demonstrated that the spatial distribution of the main demersal fishery resources in the Mediterranean GSA 15 straddle other GSAs, in particular as concerns nursery and spawning areas, indicating that some fishery resources are shared. This implies that harmonized fishery management should be applied over a larger area than is implied by the GSA concept. Finally, the study showed how data provided by different methods could be integrated to enhance the available scientific information in a data-limited situation.

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The Workshop was attended by experts from Tunisia, Italy, Libya and Malta and an international expert on fish age determination, Ms Hélène de Pontual, from the Institut Français de Recherche pour l’Exploitation de la Mer (IFREMER). The main objective of the workshop was to study the possibility of elaborating, a standard protocol on ageing in the MedSudMed Project area, based initially on two target species: Merluccius merluccius and Mullus barbatus. The current activities in the Project Area and an overview of the methods now used were presented, including existing national and international protocols and their principal technical characteristics regarding materials, methods, sampling design and data processing. Then the problems of standardizing age-reading methodology for the target species were discussed: choice of the hard structure, sampling, otolith extraction, otolith conservation, preparation techniques, accuracy and precision, validation etc. A laboratory exercise of age-reading techniques for Mullus barbatus was conducted to check the agereading agreement and precision among six readers. The average percentage agreement in respect of the modal age across all ages and readers in the comparison was 55.2% and the average coefficient of variation (CV) was 45.5%. The relative bias showed that all the readers tended to underestimate older age-classes. Finally, the participants agreed on a common protocol for age determination of the target species and proposed a future intercalibration exercise to assess the percentage agreement in age determination among readers.

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The MedSudMed Training course on macroscopic identification of maturity stages for the Mediterranean fisheries resources, Tajura, Libya, 9–11 July 2006 was primarily intended for the scientists of the Marine Biology Research Centre (MBRC) and focused on the macroscopic identification of maturity stages of demersal fishery resources. The objective was to teach the basic techniques for the processing of samples and macroscopic identification of maturity stages for different species of fish. More specifically, background information on maturity stages of demersal fishery resources, including basic notions and terminology, was provided. The course also included a general description of the reproductive organs of the main fishery resources (fishes, crustaceans and cephalopods), an analysis of slides illustrating the macroscopic identification of maturity stages in the Mediterranean species, a description of and comments on the maturity scales currently available. Practical exercises were organized with fresh samples of Sardinella aurita, Scomber japonicus and Spicara flexuosa, and simple techniques, algorithms and exercises to retrieve data on reproductive features (macroscopic) were taught. Following the biological analysis, simple elaboration of the resulting data was performed. All the participants in the course showed interest in the topics and some of them proposed the development of collaboration and new studies on the fish species distributed in the Libyan waters.

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Preliminary results on spatial distribution of some key variables (abundance indices, recruits and spawner density indices) of Merluccius merluccius and Mullus barbatus populations in central Mediterranean are presented at regional level for the first time. Data were collected during trawl surveys carried out under national programmes (Italy, Libya, Malta and Tunisia) in the MedSudMed Project area (GFCM GSAs 12, 13, 14, 15, 16 and 21). An effort to standardize the data collection and processing was made with the support of the MedSudMed Project. About 290 hauls were made within the depth range 10–800 m in May–August 2003, covering an area of about 150,000 km2. For each haul, spawners were identified as female fish whose total length was greater than the length at 50% maturity (the established common value of 30 cm TL and 15 cm TL for hake and red mullet, respectively). Also for each haul, the proportion of recruits, expressed in terms of young of the year, was estimated by analysis of the length–frequency distribution. In the case of hake, a species that reaches maturity at the age of one year, the spatial distribution of the young fish with a length lower than L50% (juveniles) was also considered. Spawning and nursery areas were identified as areas showing the highest values of spawner and recruit indices, respectively. To avoid bias due to the different sampling gears, all the indices were standardized to the maximum value, keeping separate the areas sampled with different nets. Qualitative comparison of hake and red mullet stocks among the Italian–Maltese, the Tunisian and the Libyan sub-regions, revealed that large differences exist in abundance indices and the demographic structure implicit in these indices. Though differences in the small size-classes may result from differences in gear selectivity and survey season, the contrasting distribution observed in the large size-classes is likely to result from an actual paucity of large specimens in the Italian–Maltese sub-region. Analysis of spatial distribution by life-phase showed that both species are distributed, or migrate, across the boundary of two adjacent GSAs or the boundary of a zone of national maritime jurisdiction and the adjacent high seas. Proposals for future research were made to better understand occurrence of stock units and the effect of environmental factors on them.

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The present document reviews the knowledge currently available on the biology, ecology and exploitation of Merluccius merluccius, Mullus barbatus, Octopus vulgaris and Parapenaeus longirostris, taken from the list of MedSudMed target species. Available knowledge was organized to furnish a synthetic description of these species, including species description (meristics), ecology (geographical distribution, habitats, migrations), biogical information (maximum size, spawning activity, length at first maturity, eggs, larvae and post-larvae, recruitment at habitat and nurseries, sex ratio, length–weight relationship, maximum age and natural mortality, Von Bertalanffy growth function, feeding behaviour, stock units), evaluation and exploitation (abundance indices from trawl surveys, strength of recruitment, stock assessment, fisheries, fishing zones and seasons, yield, fishing and discards). Finally a brief compilation of current fishery legislation and management in each country was made.

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The Fourth Meeting of the MedSudMed Coordination Committee was attended by representatives of the Donor (Italy), delegations from the countries participating in the Project (Italy, Libyan Arab Jamahiriya, Malta and Tunisia), the Chair of the Scientific Advisory Committee (SAC), the Deputy Executive Secretary of the General Fisheries Commission for the Mediterranean (GFCM) as well as the FAO staff of the MedSudMed Project. A brief reminder was made on the Project objectives and activities and a presentation of the activities implemented for the four MedSudMed components during the inter-session period was made. The proposed work plan for the next period was discussed and approved. It focuses on the same priorities of standardizing approaches, increasing scientific knowledge on fishery resources and ecosystems, strengthening national expertise and regional cooperation. A positive appraisal of the MedSudMed Project for supporting all the participating countries in the assessment and monitoring of the fisheries resources and for the good job carried out since the beginning was given. The belief that continuing the Project can only bring success and be beneficial for each of the participating countries was affirmed.

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The third meeting of the Coordination Committee of the MedSudMed Project (Assessment and monitoring of the fishery resources and the ecosystems in the Straits of Sicily) was attended by representatives of participating countries, a representative from the European Commission, the FAO Technical Matter officer as well as FAO MedSudMed staff. The meeting sought to present and discuss the results of the activities carried out by the Project referring to the period February 2004 - January 2005. In particular, the results of the working groups, training courses and technical consultations organized during this intercommittee period were presented. The outcome to date of all field research activities was presented and the work plan for the coming period was discussed and approved, relative to the main areas of the Project activities: spatial distribution of demersal resources in the Project area and the influence of environmental factors and fishery characteristics, small pelagic fish: stock identification and oceanographic processes influencing their abundance and distribution, marine protected areas as a tool for fisheries management. The Committee expressed its appreciation for the quantity and quality of the work carried out by the Project and for the level of coordination achieved especially concerning the standardization of methodologies at regional level.

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The MedSudMed workshop on age determination of selacean fish was held in Mazara del Vallo, Italy, from 22 November to 1 December 2004. It was attended by participants from Tunisia, Italy and Malta. The main objective of the workshop was to provide an overview of techniques currently used in the MedSudMed Project area for preparation and reading of spines and vertebrae of a series of cartilaginous fish species (Centroscymnus coelolepis, Cetorhinus maximus, Carcharhinus plumbeus, Galeus melastomus, Scyliorhinus canicula, Mustelus mustelus, Rhinobatos cemiculus, Rhinobatos rhinobatos, Raja clavata, Squalus blainvillei, Chimaera monstrosa). The course provided training and joint preparation and interpretation of samples provided by the participating institutes. Participants had agreed on a common protocol for preparation of the samples prior to the course. Direct observation of vertebrae and spines was conducted, along with tests of two methods for enhancing the appearance of the growth bands (red alizarin and cobalt nitrate). On the basis of the laboratory work and of the relevant bibliography available, trials were performed to identify the most relevant techniques for each species studied. This document details the work done during the workshop and provides general guidelines for cartilaginous fish age determination, as well as the limits of the methods currently used and improvements that could be made in the near future. It appeared that direct observation gave good results for all species except C. coelolepis. Red alizarin and cobalt nitrate staining procedures also improved the appearance of growth patterns except for C. plumbeus, Centroscymnus coelolepis and Scyliorhinus canicula and Galeus melastomus. Good results were obtained for some species (C. plumbeus, and G. melastomus), according to the size of the observed individuals. Further investigations are needed; in particular, larger samples should be examined to confirm the methods used and to provide detailed guidelines to be used at the regional level.

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The Second meeting of the Coordination Committee of the MedSudMed Project (Assessment and monitoring of the fishery resources and the ecosystems in the Straits of Sicily) was attended by representatives of participating countries (Tunisia, Malta, Libya, Italy) and other interested parties. The meeting sought to present and discuss the results of the activities carried out by the Project referring to the period September 2002 - December 2003. The outcome to date on all field research activities and strengthening national capacity building was presented, relative to the main areas of Project activity: spatial distribution of demersal resources in the Project area and the influence of environmental factors and fishery characteristics, small pelagic fish: stock identification and oceanographic processes influencing their abundance and distribution, marine protected areas as a tool for fisheries management. In particular, the results of the related expert consultations were presented, as well as the regional experts recommendations on the activities to be implemented in the next future. As a result, the work plan for the coming period was commented and approved by the participants who discussed issues touching working methodology, field work to be conducted, data processing and training in the field and at laboratory. The importance of standardizing the methodologies was stressed and considered fundamental for the Project purposes. The Project was encouraged to organize cooperative field research to provide information at regional level. The meeting was also updated on the achievements related to the regional database and information system. Future developments regarding the finalization of several modules were agreed upon and considered highly relevant by the delegates. The delegates expressed their satisfaction with the work achieved to date and with the work plan adopted and encouraged the Project to make every effort to continue strengthening the scientific cooperation between the participating countries.

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The Expert Consultation on Small Pelagic Fish: Stock Identification and Oceanographic Processes Influencing Their Abundance and Distribution was held from 1 to 3 October 2003 in Salammbô, Tunisia, and was hosted by the Institut National des Sciences et Technologies de la Mer (INSTM). The meeting was attended by 19 experts from 5 institutions in the Project Area, as well as representatives of the FAO Regional Projects AdriaMed and Copemed. Fourteen communications were presented; they covered such issues as results of stock assessment carried out by echo-surveys in the Project area, spatial distribution of the main target species, results of the acoustic identification of small pelagic fish species, reproductive strategy and reproductive biology (reproductive cycle, maturity stages, age and growth), small pelagic fisheries, spatial distribution and modelling of fishing effort, influence of meteorological and hydrographical factors on small pelagic fish. The experience of the AdriaMed Project in promoting international cooperative research on shared small-pelagic fish stocks of the Adriatic Sea was presented, as well as the main results of the Workshop on Environmental Variability and Small-Pelagic Fisheries in the Mediterranean Sea organized by the Copemed Project. The priority list of species that future activities should concentrate on was discussed in the light of the GFCM priorityspecies list, economic and ecological importance, and taking into account the peculiarities of each country. A short synthesis of gaps in the knowledge of the biotic and abiotic factors and oceanographic processes influencing the distribution and abundance of small pelagic fish species was made. The main gaps identified concern: the migration of adults, transport of eggs and larvae, and the effect of abiotic factors. Many data are presently collected during the echo-surveys, but they remain insufficient to conduct ecosystem-based studies. The lack of interdisciplinary studies in the area remains one of the main gaps. A series of proposals was discussed, dealing with: (i) spatial distribution and stock assessment of small-pelagic-fish populations; (ii) biological and genetic studies; (iii) eggs and larvae; (iv) relationships between biotic and abiotic factors and life-cycles of small pelagic fish species; (v) fishery analysis and catch and effort data. The importance of developing a functional data base for acoustic data resulting from echo-surveys was discussed and agreed upon.

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The Workshop on Standardization of Trawl Surveys Protocol in the MedSudMed Project Area was held in Mazara del Vallo from 5 to 9 May 2003. Research institutes of all four MedSudMed Countries (Italy, Malta, Tunisia and Libyan Arab Jamahiriya) were represented as well as the project staff. The objective of the seminar was to provide all available information on the existing procedures to carry out national and international trawl surveys, compare them and agree on future common methodological protocols. The technical contributions regarded four relevant topics: planning of activities at sea and fishing gears, processing of the catches and biological sampling, collecting biological information on target species, and data management and processing. On the basis of these themes three working groups were constituted, who discussed respectively: planning of activities at sea and fishing gear, collecting biological sampling and data management. In short period the participants agreed to maintain most of the current procedures used in collecting data within the national programs and adopt procedures to standardize selected data to be stored in a regional data base to be used for preliminary common analysis.

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The second Expert consultation organized by the MedSudMed Project was devoted to Marine Protected Areas as tools for fishery management. It took place in Tunis from 14 to 16 April 2003. Twenty-seven experts from research institutions in the MedSudMed participating countries, as well as experts from the FAO CopeMed Project, UNEP RAC/SPA and IUCN attended the meeting. A total of 15 presentations were given according to the terms of reference of the meeting. On the basis of the experts’ experience, an overview of several issues related to MPAs in the Mediterranean Sea was given. It highlighted the existence of expertise in the Project area as for monitoring and management of MPAs. The main points raised were: the suitable size for MPAs; impact of fishing closure and artificial reefs on stock and species diversity enhancement; impact of alien species on species diversity and strategies for their monitoring; the suitability of MPAs as fishery management tools. The meeting also allowed taking stock of the existing MPAs in some of the participating countries.

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The first Expert Consultation, Spatial Distribution of Demersal Resources in the Straits of Sicily and the Influence of Environmental Factors and Fishery Characteristics, was held in Malta from 10 to 12 December 2002. All four MedSudMed countries (Tunisia, Malta, Libya, Italy) were represented, as well as colleagues from the Copemed Project and one external expert from the University of Plymouth. As agreed during the Coordination Committee meeting, the objective of the Expert Consultation was to provide an overview of available knowledge on the issue, draw up a programme for the activities to be implemented on the basis of common methodology, propose pilot study cases and identify needs in national and regional expertise. The technical contributions regarded four main themes: fishery biology, physical environment, biocenoses, and tools and data management. A synthesis was made by working groups who provided a summary of the available knowledge and data, a listing of the gaps and recommendations to fill these gaps. Discussions were conducted towards an agreement on an indicative work plan. The adoption of common methods and terminology was considered of utmost importance. The standardization of available data and sampling design also appeared as a priority.

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The first meeting of the Coordination Committee of the MedSudMed Project (Assessment and Monitoring of the Fishery Resources and Ecosystems in the Straits of Sicily) was attended by representatives of participating countries (Italy, Libya, Malta and Tunisia) and other interested parties. The meeting was held to evaluate the first months of Project implementation, corresponding to the settlement of the Project, its start-up and the establishment of the contacts with the participating countries. An overview was given of the contacts established with the research Institutes of the participating countries, and the discussions held with the researchers. The briefing and technical meetings that were held during the initial phase of the Project were summarized, and stress was put on the content and outline of a work plan. The consequent proposal for the general outline of research has been discussed and approved for the implementation of the future activities on demersal resources, small pelagic fish and marine protected areas. Besides, the conceptual design of the future MedSudMed Information System was presented, and confidentiality and accessibility of the data were discussed. Explanations were given on the interactions between the MedSudMed Project and the MedFisis Project proposal, regarding the coordination of the statistical and related data processing activities of the FAO regional Projects in the Mediterranean. Specific requirements for the MedSudMed countries concerning national capacity building were highlighted. The Coordination Committee stressed the importance of improving activities planned to strengthen cooperation with the GFCM. Finally the priorities identified for the future and activities scheduled were listed and approved by the Project Coordination Committee.