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The management of multispecies fisheries, such as the Mediterranean bottom trawl fishery, is always a challenge. However, information on gear selectivity and discards has been studied separately so far. In this paper, the overall size-selection pattern by the trawl codend in the sea and by the fisher onboard the vessel is investigated for four commercially important fish species, Mullus barbatus, Mullus surmuletus, Pagellus erythrinus and Lophius budegassa, using different codends. For each species, the selection model used offered the possibility to simultaneously describe the escape, discard, and landing probability. The results, useful for fisheries management, showed that the codend made of 40 mm diamond meshes was always detrimental for the stocks. The 40 mm square meshes codend compared to that of 50 mm diamond meshes was more appropriate for the sustainability of both Mullus species, providing also a lawful catch along with greater compliance to the rules fisher behaviour, negligible discards and the lowest possible economic losses for the fisher. None of the codends was effective for P. erythrinus in achieving the minimum conservation reference size (MCRS) of the species. All codends were harmful to L. budegassa as the majority of juveniles were retained in the codend, resulting in negligible escapees, a high discard probability, and landings of a size much lower than the length at first maturity of the species. Further studies are needed to be conducted in the future for other species, since the trawl fishery in the Mediterranean is a multi-species fishery. © 2021 Elsevier Ltd

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

Gear selectivity and discards are important issues related to fisheries management but separately modelled. This work examines for the first time the overall size-selection pattern on the total amount of individuals of a species entering the trawl codend. An innovative approach was used based on modelling the escapement through the codend in the sea and the subsequently selection process by the fisher on the deck of the fishing vessel resulting into the discards and landings. Three different trawl codends and three species were investigated in the case study conducted. A dual sequential model accounting for both gear size-selectivity and the subsequent fisher-size-selectivity was applied, under the hypothesis that a fish entering the codend can follow a multinomial distribution with three probabilities, the escape, the discard and the landing probability, respectively. The model described the escape probability through the gear and the landing probability by the fisher as S-shaped curves leading to a bell-shaped curve for the discard probability affected by both gear and fisher selection. The model described well the experimental data in all cases. Sampling scheme of three compartments proved adequate. The model provides at the same time selectivity and discards parameters useful in fisheries management. © International Council for the Exploration of the Sea 2018. All rights reserved. For permissions, please email: journals.permissions@oup.com.

WOS: 000399341900018, Science Citation Index Expanded, This Collective Article presents information on 22 species belonging to 5 Phyla, arranged geographically from west to east. The new records were found in 8 countries as follows: Spain: first record of the two scarcely known nemerteans Baseodiscus delineatus and Notospermus geniculatus in Formentera; Malta: second record of the alien fish Lagocephalus sceleratus; Italy: the alien polychaete Syllis pectinans and the isopod Paranthura japonica, as well as the cryptogenic opisthobranch Anteaeolidiella lurana, were found in the fouling assemblages along the docks of the port of Livorno. New decapod records are reported from Sicily (the alien Callinectes sapidus and the native Pachygrapsus maurus) and Apulia (Percnon gibbesi and Procambarus clarkii); the lesser amberjack Seriola fasciata extended its geographical range to the Egadi Isands and Siganus luridus was documented for the first time along the Ionian coasts of Apulia and Calabria. Slovenia: the first record of the alien bivalve Brachidontes pharaonis is reported, together with a survey of up to date Adriatic records. Greece: the first record of the gastropod Rhinoclavis kochi is reported from Gavdos island. In addition, two records of endangered and rare cartilaginous fish were reported, namely, the shark Hexanchus griseus and the ray Leucoraja fullonica, as well as additional records of Siganus luridus for Lesvos and Malleus regula and Fulvia fragilis from Astypalaia. Turkey: the black wing flyingfish Hirundichthys rondeletii is reported for the very first time from the Black Sea. Egypt: the Indo-Pacific crab Halimede ochtodes is reported as established in Port Said. In addition, biometric parameters and meristic counts are reported for Anthias anthias in Damietta. Cyprus: the alien opisthobranch gastropod Bursatella leachii is reported for first time., Slovenian Research Agency (ARRS); East and South European Network for Invasive Alien Species [33-51/30.06.2015]; Spanish Ministry of Economy and Competiveness [BES-2013-063551, CTM2014-57949-R]; Duzce University Research Fund [2013.5.1.189]; Ministry of the Environment and Spatial Planning of Slovenia, The study coauthored by Valentina Pitacco, Lovrenc Lipej and Fabio Crocetta is part of Valentina's PhD study funded by the Slovenian Research Agency (ARRS), and was supported by the Ministry of the Environment and Spatial Planning of Slovenia. The study of alien species from Slovenia involving Fabio Crocetta was partially funded by the East and South European Network for Invasive Alien Species - a tool to support the management of alien species in Bulgaria (ESENIAS-TOOLS) (EEA funded - Contract No..-33-51/30.06.2015). Fabio Crocetta and Miquel Pontes are grateful to Alper Karabacak (Kyrenia, Cyprus) for sharing data on Bursatella leachii. Authors Gianni Insacco and Bruno Zava are grateful to the professional fisherman Mr Alessandro Bonfissuti, owner of "Erika", for providing the C. sapidus specimen studied. The authors warmly thank Maria Corsini-Foka (Hellenic Centre for Marine Research) for useful comments, which improved a previous draft of their note. Authors Aikaterini Dogrammatzi and Caterina Stamouli would like to thank Dr E. Leukaditou, J. Dokos, G. Christidis, I. Fytilakos and N. Fotiadis, members of the MEDITS scientific team, for their valuable help during samplings and also the captain and the crew of the fishing boat "TAKIS-MIMIS". Fernando Angel Fernandez-Alvarez was supported by a pre-doctoral fellowship of the Spanish Ministry of Economy and Competiveness (BES-2013-063551). His co-authors, Ivan Acevedo and Paula C. Rodriguez-Flores, were funded under the Spanish Ministry of Economy and Competiveness project CTM2014-57949-R. Ch. Mytilineou and A. Anastasopoulou would like to thank the onboard team of the EPILEXIS project (C. J. Smith, E. Lefkaditou, K. Papadopoulou, C. Stamouli, J. Dokos, G. Oikonomidis, E. Kypraiou); C. J. Smith, in particular, for the photographic material, as well as the captain and the crew of F/V 'Takis-Mimis' for supporting the survival of the Bluntnose Sixgill Shark specimen. The study of D. Yaglioglu and C. Turan was financially supported by Duzce University Research Fund, Project Number: 2013.5.1.189 and coordinated by DY. For Malta, Alan Deidun and Murat Celik are grateful to the Maltese angler - David Agius-who caught the L. sceleratus specimen reported in this study.