New records of rare species in the Mediterranean Sea (October 2021)

This Collective Article presents information about 27 taxa belonging to five Phyla (one Ochrophyta, one Cnidaria, three Arthropoda, two Mollusca and twenty Chordata) and extending from the Western Mediterranean Sea to the Levantine Sea and theBlack Sea (Sea of Marmara). The new records were reported from 11 countries as follows: Algeria: occurrence of the Africanstriped grunt Parapristipoma octolineatum; Spain: new records of eight uncommon fish species (Gadella maraldi, Hypleurochilusbananensis, Lobotes surinamensis, Parapristipoma octolineatum, Selene dorsalis, Sphoeroides marmoratus, Tetragonuruscuvieri, and Trachyrincus scabrus) from the Spanish Mediterranean; Italy: new record of the football octopus Ocythoe tuberculatafrom the Southern Tyrrhenian Sea; a rare sighting of a juvenile phase of a moray eel of the genus Gymnothorax, tentativelyidentified as Gymnothorax cf. unicolor in the Ligurian Sea; first record of adult Facciola’s sorcerer Facciolella oxyrhynchus inthe Adriatic Sea; occurrence of the tope shark Galeorhinus galeus in the Northern Adriatic Sea; Libya: first confirmed recordof the pen shell Pinna rudis; first documented record of the palaemonid shrimp Brachycarpus biunguiculatus; first record of thefish Sudis hyalina; Malta: new records of Grant’s rockling, Gaidropsarus granti; multiple concomitant reports of the rare hydromedusanspecies Aequorea forskalea; Croatia: a record of the skipjack tuna Katsuwonus pelamis in the Southern Adriatic Sea;Albania: new record of the bigeye thresher shark Alopias superciliosus; Greece: confirmation of the rare brown alga Sargassumflavifolium occurrence in the Eastern Mediterranean Sea; first record of the scaleless dragonfish Bathophilus nigerrimus; Turkey:first occurrence of the calanoid copepod Pteriacartia josephinae in the Aegean Sea; first documented record of the Cremona’s seaslug Placida cremoniana for the easternmost Mediterranean Sea; new record of the yellow-headed goby Gobius xanthocephalusin the Sea of Marmara; Cyprus: first record of the Liechtenstein’s goby Corcyrogobius liechtensteini; an individual of the Yellowfintuna Thunnus albacares captured with handline by an artisanal fisher; Lebanon: an individual of the Black marlin Istiompaxindica captured in a gill ne

Common sole in the northern and central Adriatic Sea: Spatial management scenarios to rebuild the stock

The northern and central Adriatic Sea represents an important spawning and aggregation area for common sole (Solea solea) and provides for around 20% of the Mediterranean landings. In this area, this resource is mainly exploited with rapido trawl and set nets. The stock is not yet depleted and faces a situation of growth overfishing. The comparison between the spatial distribution by age of S. solea and the geographic patterns of the rapido trawl fishing effort evidenced an overlapping of this fishing activity with the area where juveniles concentrate (age groups 0–2). The majority of spawners inhabits specific offshore areas, here defined as ‘sole sanctuaries’, where high concentrations of debris and benthic communities make difficult trawling with rapido. The aim of this study was to evaluate existing spatial management regimes and potential new spatial and tem- poral closures in the northern and central Adriatic Sea using a simple modelling tool. Two spatial simulations were carried out in order to verify the effectiveness of complementary methods for the management of fisheries: the ban of rapido trawling from October to December within 6 nautical miles and 9 nautical miles of the Italian coast. The focus of the simulation is that the effort of the rapido trawl is moved far from the coast during key sole recruitment periods, when the juveniles are moving from the inshore nursery area toward the offshore feed- ing grounds. The management scenarios showed that a change in selectivity would lead to a clear increase in the spawning stock biomass and an increase in landings of S. solea in the medium-term. The rapido trawl activity could be managed by using a different logic, bearing in mind that catches and incomes would increase with small changes in the spatial pattern of the fishing effort. The present study highlights the importance of taking into account spatial dimensions of fishing fleets and the possible interactions that can occur between fleets and target species, facilitating the development of control measures to achieve a healthy balance between stock exploitation and socio-economic factors

Relative survival scenarios: An application to undersized common sole (Solea solea L.) in a beam trawl fishery in the Mediterranean Sea

Fishery discard survival depends on multiple conditions; caution is essential when survival study outputs are employed to support management decisions. The study presents a stepwise procedure, devised to estimate discard survival, that accounts for the variability characterizing commercial fishing practices. The procedure was applied to the first survival study performed onboard rapido trawlers targeting Solea solea in the Mediterranean Sea. Undersized specimens collected during sorting were assessed for vitality; some were retained for captive observation. The main drivers affecting discard survival at the time of catch sorting (immediate survival) were identified and used to outline four different operational conditions set (scenarios). Immediate survival in each scenario was subsequently modified by applying a hazard coefficient of survival after 5 days of captive observation in relation to each vitality class, thus obtaining relative survival estimates following discarding. Temperature and air exposure duration were found to exert a major effect on survival, with catch weight and seabed type being additional important factors. The relative survival rate showed an aggregate value of 22.9% (10.5-33.4%). Scenario approach can enhance our understanding of the stressors influencing discard survival. The outcomes are discussed to explore the potential applications of the procedure to the identification of mitigation strategies

Energy loss profile measurements using the ACTAR TPC demonstrator active target

International audienceThe energy loss profiles of different ion beams (6Li, 27Al and 50Ti) impinging on CF4, isobutane and P10 have been measured with the active target ACTAR TPC demonstrator. The pressure of the gas, monitored during the experiment, has been chosen in order to stop the ions inside the active zone. Starting from the energy loss calculation produced by the SRIM code, the experimental ion tracks have been simulated, taking into account the effect of the thermal diffusion of electrons during their drift towards the pad plane under the effect of a uniform electric field. The uncertainty in the geometry, mainly due to the thickness and deformation of the mylar interface window between the gas volume and the high vacuum line, has been taken into account. A good agreement is obtained between the experimental and simulated energy loss profiles

New records of rare species in the Mediterranean Sea (May 2022)

This Collective Article presents new information about the occurrence of 21 taxa that belong to six Phyla: one Cnidaria, one Ctenophora, two Annelida, four Mollusca, two Arthropoda, and eleven Chordata. These records were reported from ten countries from the western to the eastern Mediterranean Sea as follows: Spain: early colonization signs of the Mar Menor lagoon by the cigar jellyfish Olindias muelleri; France: second record of the sea chub of the genus Kyphosus in French Mediterranean waters; Italy: first record of the marbled crab Pachygrapsus maurus in Sardinian waters; first records of the polychaetes Malmgrenia polypapillata and Levinsenia tribranchiata in the Tyrrhenian Sea; new record of the deep-sea squid Ancistrocheirus lesueurii in the Tyrrhenian Sea; first record of the pignosed arrowtooth eel Dysomma brevirostre in the Adriatic Sea; Tunisia: first documented record of the blue butterfish Stromateus fiatola and new record of the iconic great white shark Carcharodon carcharias in the Gulf of Gabes; Slovenia: first records of the sea slug Diaphorodoris alba and the sharpnose sevengill shark Heptranchias perlo; Montenegro: new record of the rare tope shark Galeorhinus galeus; Greece: new records of the rabbitfish Chimaera monstrosa and the electric ray Tetronarce nobiliana; first published record of the nuribranch Discodoris rosi; first record of the goblin shark Mitsukurina owstoni, unreported so far from the entire Mediterranean; Turkey: first record of the ctenophore Hormiphora plumosa at country level; first records of the anomuran decapod Munida speciosa and the Mediterranean tripodfish, Bathypterois mediterraneus from the Levantine Sea; Cyprus: first documented record of the nuribranch Scyllaea pelagica; Lebanon: first record of the killer whale Orcinus orca from the Levantine Sea

Enhanced α\alpha-particle production from fusion evaporation reactions leading to 46^{46}Ti

International audienceIn this paper, we report a detailed study on the de-excitation of the 46Ti compound nucleus populated by means of four different reactions: 16O + 30Si at 7 and 8 AMeV, 18O + 28Si at 7 AMeV and 19F + 27Al at 7 AMeV. The GARFIELD detection array was used to measure the light charged particles and the heavy fragments emitted. This setup covers a large fraction of the solid angle with high-granularity. Complete events are chosen through total charge (Z TOT = 22) detection. Fusion-evaporation events are selected based on the condition that only one heavy fragment is detected in coincidence with the light charged particles. The analysis of global observables, such as charge distribution and light charged particle multiplicities, is compatible with the formation of a thermalized compound nucleus for all the four reactions. Nevertheless, an enhanced emission of α-particles with respect to a pure statistical picture is observed at very forward angles (<20°). This enhancement is mainly visible in the even-Z residue exit channels populated through the emission of only α-particles

New records of rare species in the Mediterranean Sea (May 2022)

This Collective Article presents new information about the occurrence of 21 taxa that belong to six Phyla: one Cnidaria, one Ctenophora, two Annelida, four Mollusca, two Arthropoda, and eleven Chordata. These records were reported from ten countries from the western to the eastern Mediterranean Sea as follows: Spain: early colonization signs of the Mar Menor lagoon by the cigar jellyfish Olindias muelleri; France: second record of the sea chub of the genus Kyphosus in French Mediterranean waters; Italy: first record of the marbled crab Pachygrapsus maurus in Sardinian waters; first records of the polychaetes Malmgrenia polypapillata and Levinsenia tribranchiata in the Tyrrhenian Sea; new record of the deep-sea squid Ancistrocheirus lesueurii in the Tyrrhenian Sea; first record of the pignosed arrowtooth eel Dysomma brevirostre in the Adriatic Sea; Tunisia: first documented record of the blue butterfish Stromateus fiatola and new record of the iconic great white shark Carcharodon carcharias in the Gulf of Gabes; Slovenia: first records of the sea slug Diaphorodoris alba and the sharpnose sevengill shark Heptranchias perlo; Montenegro: new record of the rare tope shark Galeorhinus galeus; Greece: new records of the rabbitfish Chimaera monstrosa and the electric ray Tetronarce nobiliana; first published record of the nuribranch Discodoris rosi; first record of the goblin shark Mitsukurina owstoni, unreported so far from the entire Mediterranean; Turkey: first record of the ctenophore Hormiphora plumosa at country level; first records of the anomuran decapod Munida speciosa and the Mediterranean tripodfish, Bathypterois mediterraneus from the Levantine Sea; Cyprus: first documented record of the nuribranch Scyllaea pelagica; Lebanon: first record of the killer whale Orcinus orca from the Levantine Sea