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The process of the development of a citizen science platform on Ocean Literacy designed and implemented during the lock down period of 2020 is described. As restrictions due to the COVID-19 health emergency did not allow researchers to organise public events and field data collection activities related to Ocean Literacy, it was decided to take advantage of this situation by building an online platform to bring Ocean Literacy issues directly into citizens' homes. The massive use of digital tools by all civic communities during this time has enabled both the implementation of this idea and rendering it effective. The pandemic control measures then provided a unique opportunity to focus citizen attention on the collection of household data and information and to highlight the more or less direct connections between citizens' lifestyles and the eco-marine system. Short questionnaires were used to ascertain and highlight citizens' household behaviours and daily attitudes during the lockdown towards water use, seafood consumption and plastic material use and disposal. Data and information were also proposed, collected and analyzed in terms of: general environmental awareness of the respondents, perception regarding their purchasing choices during this particular period, as well as any changes in lifestyles and habits during the lockdown with respect to previous periods. The collected data enabled the improvement of our knowledge on some aspects of people's domestic habits as well as their perception vs. real knowledge about the proposed environmental issues. We also realized that it is increasingly crucial for scientists to directly and extensively involve people and schools in educational and outreach activities and events as a good practice of science-society interaction. But to achieve good results there is a need to develop appropriate communication tools and effective involvement strategies to promote their widespread participation in citizen science projects.

This study reports the shapes, dimensional classes, types and counts of microplastics (MPs) found in 23 individuals of N. norvegicus collected from two wild populations of the Adriatic Sea (Mediterranean basin). The focus was on three different anatomical compartments (gut, hepatopancreas and tail), which were analysed separately. MPs were found in all the investigated individuals with an average of about 17 MPs/individual. Fragments were predominant over fibers with a ratio of about 3:1. The majority of MPs were in the dimensional range 50–100 μm. The predominant polymers were polyester, polyamide 6, polyvinyl chloride and polyethylene, which together constitute about 61% of all the MPs found. Fragments were more concentrated in the hepatopancreas, with no significant difference between gut and tail, while fibers were more concentrated in the gut than in the tail with hepatopancreas somehow in between. The dimensional class of the MPs influences their anatomical distribution. There were no statistical differences among individuals from the two sampling sites. Sex of the individual did not influence the level of retained MPs, while length had a very marginal effect. The information reported here contributes to understanding of the possible risks linked to human consumption of different tissues from contaminated Norway lobsters.

In this study we analysed total mercury (THg) levels in European hake (Merluccius merluccius) - an ecologically and commercially important species throughout the Mediterranean - caught in the northern and central Adriatic Sea. To the best of our knowledge, this is the first study evaluating THg levels in hake fillets in relation to ecological (season) and biological (body size, sex, sexual maturity, lipid content) parameters. THg levels in muscle showed no sex-related differences; in contrast, significant season-related differences were found in females, with higher levels in spring-summer compared with autumn-winter. No season-related differences were seen in males. A significant sex effect was found for body size and sexual maturity. Females showed a correlation between THg level and length, THg being significantly higher in mature compared with immature specimens. No significant sex effect was found for muscle lipid content, because a correlation between THg concentration and tissue lipids was found in both sexes. Since the mean THg concentration found in M. merluccius fillets (0.64 ± 0.29 mg kg

Norway lobster (Nephrops norvegicus) is one of the most important crustacean species in terms of landings and commercial value for the Adriatic Sea. In this zone, this stock is composed by two different subpopulations, characterised by different growth features. This study focus on the biology of individuals from the two most important fishing grounds of the area, namely the “off Ancona” area and the Pomo/Jabuka pits. The size at the onset of first maturity (SOM) for both males and females were determined by means of macroscopic techniques: gonad tissue was examined for females, whereas the relation between carapace length and appendix masculina (length and width) was investigated for males. The estimated SOMs underline the differences between these two subpopulations, even if only the relationship between the carapace length and the length of the appendix masculina of the Pomo/Jabuka pits is statistically sound. Males from the Pomo/Jabuka pits mature at carapace length (CL) between 24.33 ± 0.32 and 25.39 ± 0.81 mm, corresponding to the SOM estimated respectively from the length and the width of the appendix masculina. Estimated L50 for females is 21.14 mm CL within the Pomo/Jabuka pits and 30.83 mm CL in the “off Ancona” area. These results underline the fact that the subpopulations living in the “off Ancona” fishing ground matures at bigger length compared to that one inhabiting the Pomo/Jabuka pits. This is in line with the other analysis carried out within this study, that show the presence of larger individuals in the “off Ancona” fishing ground, whereas small individuals characterize the Pomo/Jabuka pits. These differences have to be taken into account when managing this stock.

Teleosts have many spawning strategies and the hormonal control of gametogenesis is not well defined among the species or even, between sexes. To increase the knowledge of gonadotropin hormones, we studied the trend by gene expression of gonadotropin receptors in the follicles and testis at different maturity stages in the European hake (Merluccius merluccius), a multiple-spawning species. With this aim, fshr and lhr were sequenced, characterized, and their gene expression was quantified in oocytes and in testes at different maturity stages. The deduced amino acid sequences were used to phylogenetic studies and evidenced that both receptors are phylogenetically closed to other gadoid species. The gene expression of both receptors was poorly expressed in primary follicles, increased in vitellogenic follicles and to later decrease in hydrated oocytes. In testis, highest levels of lhr were detected during spermiation, while levels of fshr were constant. For the first time, a histological analysis was performed in European hake testes showing an unrestricted lobular testis. To better elucidate the mechanisms involved in the oogenesis of the European hake, the expression of estrogen receptor and cyp19a was also investigated displaying high levels in all classes of follicles. All these data allow to increase the knowledge on reproductive physiology of an important socioeconomical species and it seeks to shed more light on the role of the receptors here studied during gametogenesis of multiple-spawning fish.

In vertebrates, the regulation of gametogenesis is under the control of gonadotropins (Gth), follicle-stimulating hormone (Fsh) and luteinizing hormone (Lh). In fish, the physiological role of Gths is not fully understood, especially in species with asynchronous ovarian development. To elucidate the role of Gths in species with asynchronous ovary, we studied European hake (Merluccius merluccius) during the reproductive season. For this aim, we first cloned and sequenced both hormones. Then, we characterized their amino acid sequence and performed phylogenetic analyses to verify the relationship to their orthologues in other species. In addition, the quantification of gene expression during their natural reproductive season was analyzed in wild-caught female hake. Our results revealed that fshb peaked during the vitellogenic phase, remaining high until spawning. This is in contrast to the situation in species with synchronous ovary. lhb, on the other hand, peaked during maturation as it is also common in species with synchronous ovarian development. Finally, combining double-labeling fluorescent in situ hybridization (FISH) for Gth mRNAs with immunofluorescence for Lh protein, we evidenced the specific expression of fshb and lhb in different cells within the proximal pars distalis (PPD) of the pituitary. In addition to gonadotrope cells specific to expression of either fshb or lhb, some cells showed co-expression of both genes. This suggests either that gonadotropes with co-expression are not yet specified or they could have a plasticity that permits changes from one cell phenotype to another during certain life stages and in turn during different physiological states.

In the present study the genetic variability of European sardine from Adriatic and Ionian seas was investigated in order to detect the occurrence of genetic structure within and between these basins. In several samples the analysis of genetic variability at eight microsatellite loci showed a number of homozygote individuals higher than expected at Hardy-Weinberg equilibrium. The inter-population differentiation level estimated by AMOVA, qST and r R ST and Bayesian descriptors detected no signs of population differentiation between the samples analysed. These results are consistent with previous studies based on allozymes and several mitochondrial DNA markers and add further evidence contradicting the early identification, based on morphological and reproductive data, of two sub-populations in the Adriatic Sea.

Lungo la costa toscana l'attività di pesca professionale più diffusa è quella artigianale, definita anche piccola pesca: circa 470 imbarcazioni con 800 addetti che catturano 1300 tonn annue per un ricavo di oltre 13 milioni di euro, esercitata da imbarcazioni di LFT

Age and growth of the brown meagre Sciaena umbra (Sciaenidae) collected (n = 532) in the north-western Adriatic Sea was studied by means of transverse otolith sections. The maximum age estimated was 19 and 16 years for males and females, respectively. The length at age estimated for each sex indicated that females attain a larger size and grow slightly faster than males. Both marginal increment analysis and edge analysis confirmed that annuli are formed once a year, with opaque zones laid down in summer (June-July). Age readings were very precise, with a percentage agreement of 98% between readers and low values of the index of average percent error (0.9%) and coefficient of variation (1.3%). Von Bertalanffy growth function was fitted to age-length data, and growth parameters were estimated for males (L∞ = 44. 9c m;k = 0.27, t0 = −2.17 years) and females (L∞ = 47. 2c m;k = 0.28, t0 = −1.82 years). In both sexes of brown meagre, growth rate was high until they attain 2-3 years of age, i.e. at sexual maturity. Most of catches were obtained in late summer-early autumn. On the basis of present data, the sampled population of brown meagre mostly consisted of small fish younger than three years of age (about 90%). In addition, landings of this species in recent years largely decreased. As reported elsewhere in north-western Mediterranean, brown meagre stock in the Adriatic Sea showed clear signs of depletion, thus specific management measures for this species are urgently required.

Mid-water pair trawling (PTM) targeting small pelagic resources represents a key fishing activity in the Adriatic Sea. This fishery is experiencing a long period of crisis due to resource depletion and the lack of appropriate market strategies, and vessels spend most of the time searching for fishing schools. The searching strategy largely depends on the interaction between vessels: the captains of the {PTM} units take their decision also checking the position and the fishing status of other vessels. Understanding this strategy represents a key step towards a more effective resource management, since strategies directly determine the pattern of fishing effort. A Conditional Logit model has been devised to analyze fishermen's strategy as a non-cooperative game. This category of games is characterized by the existence of (at least) one equilibrium point - a Nash Equilibrium - in which each player plays his strategy, that is a Best Response to the strategies of the other players. This equilibrium point was estimated for the different scenarios defined by environmental (sea surface temperature and atmospheric pressure) and economic (fuel and fish prices at market) variables. Vessel Monitoring System data were used to capture fleet activity, while different datasets were collected to reconstruct environmental and economic drivers. Results indicate a good predictive power of the model, and suggest that the equilibrium strategy that guides units' behaviour is invariant with respect to environmental conditions, whereas it is largely influenced by economic factors. These latter, via strategies, may determine important consequences on the resources in terms of exploited areas and the impact of fishing activity. In particular, a low fuel price when fish price is high leads to higher values of CPUE, and then to a more efficient but also impacting fishing activity.

Analytical stock assessment of sardine ( Sardina pilchardus , Walb.) in the Adriatic Sea from 1975 to 1999 was performed taking into account the occurrence of discarding at sea of sardine caught by the Italian fleet. We have attempted to model the fishermen’s behaviour using data collected by an observer on board fishing vessels. This enabled us to estimate the amounts of discards, which were added to the catches landed, collected by ISMAR-CNR Ancona. Discards were calculated for the period 1987-1999, as their values were negligible before 1987. Stock assessment on the entire data series from 1975-1999 was carried out by means of Virtual Population Analysis (VPA). Discarding behaviour differs among ports due to different local customs and market conditions. The quantity added to the annual total catch ranged from 900 tonnes to 4000 tonnes, corresponding to between 2% and 15% of the total corrected catch. VPAs indicated that mid-year sardine stock biomass rose steadily from 400,000 tonnes in 1975 to a peak of 950,000 tonnes in 1984. Subsequently, biomass declined steadily to the more recent values, around 300,000 tonnes. Although discarded quantities were relatively high, their influence on stock assessment was not strong because of the high level of both catch and, in particular, estimated biomass at sea.

The reproductive biology of two commercially important flat fish, turbot (Psetta maxima) and brill (Scophthalmus rhombus), in the Adriatic Sea was investigated by histology and macroscopic analysis of gonads. Different patterns of vitellogenesis and spawn ing were observed in the two species. In turbot, gonad develop ment culminates annually from March to May and the seasonal egg batch develops synchronously, the eggs becoming ready at about the same time. In brill, the ovary contains several oocyte batches in different stages of maturity, indicating intermittent re lease of ripe eggs in the course of a long spawning season (Janu ary‐July). These data are discussed and compared with observa tions on reproduction of turbot and brill for other areas of their distribution ranges.