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The study of small pelagic fish by hydroacoustic methods in the Mediterranean Sea began in the Adriatic in the 1950’s. Since 2009, internationally coordinated, extensive, regular surveys have been conducted in the framework of the MEDIAS - Mediterranean International Acoustic Surveys – action, under the EU Data Collection Framework, to provide inputs for the management of small pelagics, particularly European anchovy (Engraulis encrasicolus) and European sardine (Sardina pilchardus). The surveys cover EU Mediterranean waters and monitor the distribution and abundance of small pelagic species using a common protocol. The hydroacoustic surveys, historically conducted by each Country separately, have since been standardized and harmonized. This is a review of the evolution of the surveys from the beginning up to the present and discusses the future prospects. It reports the historical time series of anchovy, sardine and other small pelagics in different areas and describes the spatial and temporal distribution of small pelagic species in decadal maps of the major areas of their distribution in the European Mediterranean Sea. Furthermore, it discusses the use of MEDIAS data for stock assessment purposes, the collection of auxiliary information for an ecosystem-based management approach, the need for further standardization and future challenges. Versión del editor

The reduction of juvenile catch and discards are important targets in fisheries policy. This work examines how selection models can predict the size structure (LFD) of discards and landings considering the effects of area, time period, gear and fisher behaviour. Additional exploitation indicators related to the gear used, fisher's selection pattern, and discards were also estimated. The approach is demonstrated in a study concerning hake in the Mediterranean trawl fishery, focusing on high (HRA) and low (LRA) recruitment areas in Saronikos Gulf (Eastern Mediterranean) during two periods (June, September) using two codends (40 mm square - 40S, 50 mm diamond - 50D mesh). The predicted discards LFDs revealed generally higher percentages in the HRA in June when using the 50D codend. The predicted landings LFDs showed higher percentages in the LRA in September for both codends, but undersized hake were always included. LFDs and exploitation indicators indicated that both codends were inappropriate for sustainable fishing of hake in the HRA, where 50D performed worse than the 40S. Fishing with both codends in the LRA in September revealed the lowest discards rates and minimum sizes of landings close to MCRS (minimum conservation reference size). These results can provide information to fisheries management aiming to protect juveniles and reduce discards through spatio-temporal fishing closures. © 2020

The Scientific, Technical and Economic Committee for Fisheries (STECF) not hold its 63rd Plenary Meeting as originally foreseen on 16-20 March 2020 but was requested to draft its advice by written procedure instead.-- 94 pages, The STECF was originally planned to meet in plenary on 16-20 March at the JRC, Ispra. Due to the emergent covid-19 situation in northern Italy and later on the whole of Europe, the meeting was first shifted to Brussels, and then cancelled and replaced by a written procedure with STECF members addressing the ToRs from their home offices. The original ToRs were re-prioritised by the Commission in order to facilitate the STECF working under non-ideal conditions. In addition, the Commission supported the STECF chair and vice-chair, rapporteurs and those STECF members being able to contribute to the written procedure by issuing individual ad hoc contracts. Below DG MARE lists the points to be developed under written procedure. All other points originally included in the draft ToR and Agenda are either postponed to one of the future plenaries or to be dealt with under different procedures, or will no longer be dealt with by STECF. After consultation within DG MARE, this exceptional written procedure to replace the Plenary March session, will need to deal with the following points and ToR. These concern, in summary: - 2 points in the Atlantic – both technical measures - 3 points in the Med – some diversity in the subject - 1 point in the Black Sea – on data collection. Finalization of the written procedure on all topics was foreseen for 3 April 2020

The Scientific, Technical and Economic Committee for Fisheries (STECF) held its 65th plenary as virtual meeting from 9-13 November 2020.-- 152 pages, Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines

The Scientific, Technical and Economic Committee for Fisheries (STECF) hold its 60th plenary on 25-29 March 2019at JRC, Ispra, Italy.-- 159 pages, Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines

The site-attachment behaviour of O. melanura settlers was examined in an estuarine area of western Greece. The approach that was followed included underwater assignments of shoal identities and continuous recording of specific behavioural traits. Variations between ontogenetic stages with respect to the pattern of residence at the sites were quantified via an index (the residence-persistence index (RPI)) devised for this purpose. Our findings suggest that this species initiates settlement in small shoals that occupy specific sites at the substratum where they reside for various days. This behavioural trait is stage-specific and gradually diminishes as the fish complete metamorphosis, while at the same time they change their social organisation. Such an ontogeny-dependent site-attachment behaviour has not been described before and is markedly different from that described for other members of the Sparidae family. En este trabajo se ha examinado el comportamiento de asociación al substrato de los individuos recién asentados de Oblada melanura en un área estuárica de Grecia occidental. El estudio se hizo en base a la identificación de los bancos y al seguimiento continuo de las características conductuales específicas a lo largo del tiempo. Las variaciones ontogenéticas respecto a la pauta de residencia en los diferentes lugares han sido cuantificadas mediante un índice (índice de residencia-persistencia (RPI) específicamente desarrollado para este fin. Nuestros resultados sugieren que esta especie inicia el asentamiento en pequeños bancos que ocupan lugares específicos del substrato en donde residen varios días. Esta característica conductual es específica del estadio de desarrollo y disminuye gradualmente a medida que los peces acaban su metamorfosis, mientras que, al mismo tiempo, cambian su organización social. Esta conducta de asociación con el lugar de asentamiento, dependiente de la ontogenia, no se había descrito anteriormente y es marcadamente diferente a la que ha sido documentada para otros miembros de la familia Sparidae.

A 1-D full-life-cycle, Individual-based model (IBM), two-way coupled with a hydrodynamic/ biogeochemical model, is demonstrated for anchovy and sardine in the N. Aegean Sea (Eastern Mediterranean). The model is stage-specific and includes a ‘Wisconsin’ type bioenergetics, a diel vertical migration and a population dynamics module, with the incorporation of known differences in biological attributes between the anchovy and sardine stocks. A new energy allocation/egg production algorithm was developed, allowing for breeding pattern to move along the capital-income breeding continuum. Fish growth was calibrated against available size-at-age data by tuning food consumption (the half saturation coefficients) using a genetic algorithm. After a ten-years spin up, the model reproduced well the magnitude of population biomasses and spawning periods of the two species in the N. Aegean Sea. Surprisingly, model simulations revealed that anchovy depends primarily on stored energy for egg production (mostly capital breeder) whereas sardine depends heavily on direct food intake (income breeder). This is related to the peculiar phenology of plankton production in the area, with mesozooplankton concentration exhibiting a sharp decrease from early summer to autumn and a subsequent increase from winter to early summer. Monthly changes in somatic condition of fish collected on board the commercial purse seine fleet followed closely the simulated mesozooplankton concentration. Finally, model simulations showed that, when both the anchovy and sardine stocks are overexploited, the mesozooplankton concentration increases, which may open up ecological space for competing species. The importance of protecting the recruit spawners was highlighted with model simulations testing the effect of changing the timing of the existing 2.5-months closed period. Optimum timing for fishery closure is different for anchovy and sardine because of their opposite spawning and recruitment periods. © 2019 Gkanasos et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Alheit, Jürgen ... et. al.-- Report of the Working Group on Small Pelagic Fish, their Ecosystems and Climate Impact (WGSPEC), SCICOM Steering Group on Ecosystem Processes and Dynamics (SSGEPD), 30 March-3 April 2015, Thessaloniki, Greece.-- 22 pages, 4 annexes

109 páginas, 53 figuras, 5 tablas, The present chapter deals with the estimation of female fecundity in fishes, mostly teleosts. The chapter is organized in three main blocks. The first block is devoted to technical issues of fish fecundity measurements from fixation, preservation and treatment of ovarian material to automatic oocyte counts. The use of certain staining protocols for the identification of follicular types in ovarian whole mounts and of inexpensive equipments in oocyte counting is also described. Because histology still constitutes the most unbiased method for identifying ovarian structures an array of stereological methods for estimating follicular intensity from assumption/model based methods (e.g. Weibel and oocyte packing density (OPD) method) to assumption/model free methods such as the physical disector or the fractionator principle is also provided. The second block is focused on methods used for the estimation of important variables such as batch fecundity (using hydrated oocytes and or previous developmental stages), daily fecundity and spawning fraction, S. Special emphasis is given to the estimation of S; the postovulatory follicle (POF) method is explicitly described together with its most common bias issues related to POF staging and ageing. In addition, methods that are based on imminent spawners, methods for stocks with high S values, and methods based on the assessment of spawning sites are also descibed. The third block incorporates knowledge acquired in the two other blocks to review what is needed to estimate the annual realized fecundity (the ultimate goal of fecundity studies) in determinate and indeterminate fish species. The autodiametric method for estimating potential annual fecundity, and the impacts of fecundity dowregualtion by atresia and of skipped-spawning in determinate spawners are also included. In short, this chapter will offer the reader an overview of all methodological aspects that need to be considered in fish fecundity investigations., COST Action FRESH (FA0601). NAFO Working Group on Reproductive Potential

A new type of vertebral malformation is described, consisting of deformed cartilaginous neural and haemal processes and the compression and fusion of vertebral bodies. The malformation is designated as haemal vertebral compression and fusion (haemal VCF). We studied the aetiology of the malformations and described microanatomical histopathological alterations. The malformations were detected during routine quality control in one of six monitored Gilthead sea bream populations. Haemal VCF affected the posterior part of the vertebral column (haemal vertebrae). In 20% of the deformed specimens, haemal VCF was combined with lordosis. At 35dph (days post-hatching), early anatomical signs of the haemal VCF consisted of abnormal centrum mineralization, malformed cartilaginous neural and haemal processes and developing lordotic alterations. The histological examination of the deformed individuals revealed that haemal VCF is preceded by notochord abnormalities. The frequency of deformed individuals was three times higher at 35 than at 61dph (50.3% vs. 17.2%, n=157 and n=250, respectively). No signs of repair or reversion of malformations have been observed. Thus, the steep decrease in deformities in older animals suggests that haemal VCF is linked to high mortality rates. The results are discussed in respect of the possible causative factors of haemal VCF.

A new type of vertebral malformation is described, consisting of deformed cartilaginous neural and haemal processes and the compression and fusion of vertebral bodies. The malformation is designated as haemal vertebral compression and fusion (haemal VCF). We studied the aetiology of the malformations and described microanatomical histopathological alterations. The malformations were detected during routine quality control in one of six monitored Gilthead sea bream populations. Haemal VCF affected the posterior part of the vertebral column (haemal vertebrae). In 20% of the deformed specimens, haemal VCF was combined with lordosis. At 35 dph (days post-hatching), early anatomical signs of the haemal VCF consisted of abnormal centrum mineralization, malformed cartilaginous neural and haemal processes and developing lordotic alterations. The histological examination of the deformed individuals revealed that haemal VCF is preceded by notochord abnormalities. The frequency of deformed individuals was three times higher at 35 than at 61 dph (50.3% vs. 17.2%, n = 157 and n = 250, respectively). No signs of repair or reversion of malformations have been observed. Thus, the steep decrease in deformities in older animals suggests that haemal VCF is linked to high mortality rates. The results are discussed in respect of the possible causative factors of haemal VCF.

The Scientific, Technical and Economic Committee for Fisheries hold its 43rd plenary on 8-12 July 2013 in Brussels (Belgium). The terms of referenceincluded both issues assessments of STECF Expert Working Group reports and additional requests submitted to the STECF by the Commission. Topicsdealt were inter alia assessments of the economic performance of the EU fishing fleet, fishing effort regime evaluations, future EU data collection, andreview of stock advice.

The Scientific, Technical and Economic Committee for Fisheries hold its 41st plenary on 5-9 November 2012 in Brussels (Belgium). The terms ofreference included both issues assessments of STECF Expert Working Group reports and additional requests submitted to the STECF by the Commission.Topics dealt were inter alia assessments of Mediterranean and Black Sea stocks, evaluations of fishing effort regimes, technical measures, review ofscientific advice on stocks and fisheries of EU interest, fisheries management plans evaluation issues.

The Scientific, Technical and Economic Committee for Fisheries hold its 39th plenary on 16-20 April 2012 in Brussels (Belgium). The terms of referenceincluded both issues assessments of STECF Expert Working Group reports and additional requests submitted to the STECF by the Commission. Topicsdealt with ranged from fisheries economics to management plan evaluation issues.

The Scientific, Technical and Economic Committee for Fisheries hold its 38th plenary on 7-11 November 2011 in Brussels (Belgium). The terms of reference included both issues assessments of STECF Expert Working Group reports and additional requests submitted to the STECF by the Commission. Topics dealt with ranged from fisheries economics to management plan evaluation issues.

This corrigendum should replace the corresponding section 8.4 of the 38th Plenary meeting report of the Scientific, Technical and Economic Committee for Fisheries (PLEN-11-03). Publications Office of the European Union, Luxembourg, EUR 25033 EN, JRC67714.

The Scientific, Technical and Economic Committee for Fisheries hold its 36th plenary on 11-15 April 2011 in Barza d'Ispra (Italy). The terms of reference included both issues assessments of STECF Expert Working Group reports and additional requests submitted to the STECF by the Commission. Topics dealt with ranged from fisheries economics to management plan evaluation issues[...]

EWG-11-11 meeting was held on 26 – 30 September 2011 in Cadiz (Spain). This Section of the report covers the Deep Sea and Western Waters and provides fleet specific trends in catch (including discards), nominal effort and catch (landings) per unit of effort in order to advise on fleet specific impacts on stocks under multiannual management plans. STECF reviewed the report during its November 2011 plenary meeting.