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The Black Sea Rapa whelk (Rapana venosa, Valenciennes 1846) is, on one hand, a nonindigenous species harming Black Sea benthic ecosystem and on the other hand, since its everexpanding stock found market in the Far East, one of the most profitable in the basin. For this purpose, the Working Group on the Black Sea (WGBS) under General Fisheries Commission for Mediterranean and Black Sea (GFCM) agreed on the fact that, despite the invasive nature of the species, its stock in the Black Sea should be exploited within biologically safe limits. In order to cover the area of study in high percentage, a number of 51 stations were proposed for Romanian coast, that were distributed evenly. The duration of one haul was 30 minutes and the hauls were performed at a constant depth and rectilinear in a big percentage, but to avoid tangles and gear destruction, some deviations have been made. Age composition in 2020 was formed by 3 to 12 years generations, the percentages were recorded for 6- and 7-years classes. Regarding 2021 data, the age composition was composed by 3 to 11 years, with the numbers recorded for 5- and 6-years classes. Highest abundance and biomass values for rapa whelk in 2020 have been recorded in the north part of the Romanian coast in the sectors Zaton, Sahalin, Sf. Gheorghe and Mila 9. For 2021, data no significant changes were observed. [ABSTRACT FROM AUTHOR]

The appropriate segmentation of fishing fleets is controversially discussed in fisheries research and management and a variety of approaches has been introduced. The present approach, developed in a pilot study funded by the European Commission - Data Collection Framework (DCF), introduces a standardized multivariate approach for characterizing fisheries fleet segments by hierarchical agglomerative cluster analysis (HAC) of their catch composition. We chose data from 2021 of the Romanian fishing fleet as the basis of our analysis. Statistical analyses were performed using the program RStudio V3.6.1 by running the fleet segmentation package script. The specific indices, tests, and visual validation methods of the package were applied to determine the optimal number of clusters. The procedure was finalized by a post-hoc validation of the clustering result to identify the actual fleet segments. From the basic data, 6 fleet segments for Vessels using active and passive gears (PMP) were highlighted, representing 52 boats, where it was noted that fishing at Rapa whelk (RPW) prevailed with 91.94% of the total catches on the segment, respective 5 fleet segments for Vessels using passive gears (PG) only for vessels <12m, representing 78 vessels where the main catches or recorded at European anchovy (ANE) 25.16%, turbot (TUR) 13.08%, horse mackerel (HMM) 8.75%, thus 130 vessels from two classes of different gears in total. We detected mixed fishing, especially on various assemblages of demersal and pelagic fish, as well as target fishing on demersal and pelagic fish, Rapa whelk, and mussels. For a better understanding of the approach, further research is needed. [ABSTRACT FROM AUTHOR]

The European Common Fisheries Policy aims to gradually eliminate discards in all European Union fisheries through the introduction of a landing obligation for all catches of species subject to catch limits (turbot and sprat for the Black Sea). In 2016, the Commission established a discard plan for turbot fisheries in the Black Sea, that provided for a survivability exemption of turbot caught with bottom-set gillnets, applied from 1 January 2017 until 31 December 2019. Subsequently, Romania and Bulgaria submitted an updated Joint Recommendation to the Commission, requesting the renewal of the discard plan and the survivability exemption based on the high survival rates of this species. The Scientific, Technical and Economic Committee for Fisheries (STECF) acknowledged the existence of data demonstrating the high survivability of turbot caught by vessels from non-EU countries using the same gears, however they requested that Member States concerned should submit additional data on survival estimates relating to the gillnet fishery for turbot. In this context, NIMRD "Grigore Antipa" was commissioned by the Romanian National Agency for Fisheries and Aquaculture (NAFA) to perform a pilot study aiming at obtaining scientific evidence for the exemption of turbot from the landing obligation, carried-out during January-April 2022. Scientific fishing was performed in the Romanian marine area with specialized gears - turbot gillnets on board of NIMRD's boat. The methodology consisted of launching the gillnets in established locations and recovering them after a soaking time depending on weather conditions. After each operation to recover the nets from the water, all turbot specimens caught were retained on board, parked in a fiber-reinforced polymer (FRP) container filled with seawater and equipped with an aeration system. The specimens were kept in the tank for 1 hour, during which time they were monitored from the point of view of their condition (dead, alive, injuries, other negative effects produced by the fishing gear). Subsequently, all turbot specimens declared viable were released back into the sea. The results indicate high survivability rates of turbot caught in gillnets (81.67%). Some injuries were reported in the dead specimens, probably caused by the mechanical action of the gear. [ABSTRACT FROM AUTHOR]

Due to the current situation when we observe numerous climate changes, manifested by rising air and seawater temperatures, there have been observed also, changes in recent years regarding the biology aspects of some fish species from the Romanian Black Sea coast. Trachurus mediterraneus (Steindachner, 1868) - horse mackerel, having economic importance it is necessary to observe its biology in order to develop an appropriate management required by the changes observed at the population level. This paper presents results on temporal variations of total length and weight, age composition, growth parameters and sex ratio of the Mediterranean horse mackerel from the Romanian Black Sea coast. Data were collected from commercial trap net catch and from pelagic trawl expeditions in the period 2018-2020. Significant differences were observed between the length distribution and the stations, with the specification that in 2020 individuals from classes of smaller lengths predominated compared to previous years. [ABSTRACT FROM AUTHOR]

Living marine resources obviously contribute to the survival of humanity. Unfortunately, numerous studies highlighted that marine biological diversity faces various threats related to overfishing and illegal fishing, pollution (marine and terrestrial), invasive species, marine litter and climate change. In this context, the incidental catch of vulnerable species (i.e., elasmobranchs, marine mammals, seabirds) is considered one of the main threats to good environmental condition of the marine fauna. The aim of the study conducted in 2020, was to highlight the impact of fishing activities on aquatic resources, especially on vulnerable fish species as picked dogfish Squalus acanthias), thornback ray (Raja clavata) and common stingray (Dasyatis pastinaca), marine mammals and seabirds. The background information was collected by observations from scientific trawl surveys by pelagic and demersal trawl gears, observations from stationary fishing points, observations from commercial beam-trawl fishing operations. The analysis of logbooks of several economic operators and data collected by observers on board vessels, highlighted the low bycatch rate for vulnerable species in most fishing gear. [ABSTRACT FROM AUTHOR]

As the horse mackerel Trachurus mediterraneus (Steindachner, 1868) is one of the most exploited commercial species of the Black Sea fisheries, the knowledge of its different biological aspects related to growth and reproduction is highly important. This paper presents preliminary results of the analysis of morphological measurements (total length, total weight), Fulton relative body condition index, age, sex and degree of maturity of the horse mackerel population from the Romanian Black Sea coast. 563 individuals were collected between June and November in 2013, 2014, 2015 and 2018, from trawl and trap net catches. Their mean total length was 11.4 ± 2.4 cm, their mean total weight was14.4 ± 8.5 g and they had between 0 and 4+ years with a mean age of 1.7 ± 1.1 years. The data analyses of their measurements highlighted significant temporal differences between years and months, but no differences occurred between areas and sexes. These results should contribute to a better knowledge of the biology of the horse mackerel and may help to improve the management of the stock of this species for sustainable fisheries. [ABSTRACT FROM AUTHOR]

The horse mackerel is a pelagic marine species of commercial interest at the Romanian Black Sea coast. The present study presents the analysis of the age of horse mackerels at the first sexual maturıty. For the determination of age, the method used was the interpretation of the otoliths, these are bone structures located in the inner ear. Age of sexual maturity of horse mackerel is 1-2 years. As a general rule, a fish population is considered to be in a good condition when the age at first sexual maturation exceeds 30% of the individuals present in the catch. The analyzed periods were 2012-2015 and 2016-2017. In the period 2012-2015, the percentage of the age of the first sexual maturation exceeded the 30% threshold compared to the 2016-2017 period when a decrease was recorded. The reduction is mostly due to fishing pressure on these species. In conclusion, it can be said that the horse mackerel population on the Romanian Black Sea coast is not in good condition status, and measures are needed to conserve the population. [ABSTRACT FROM AUTHOR]

As a result of the increasingly concern of people regarding the food safety, different public media focused on the data collected from reference laboratories inducing a false perception regarding the threat of sea food consumption. Starting with the Minamata disaster more and more people became worried about the sea water pollution with heavy metals. Using the reference data of Commission Regulation (EC) No 1881/2006 setting maximum levels for certain contaminants in foodstuffs and the Codex Alimentarius, 21 fish species from sea water or freshwater were studied for Cd, Mg and Pb. The data were collected from specialized laboratories during the following years: 2016 and 2017. The obtained results were in the acceptable limits for European standards. For 67 of 110 samples the value of LOD/LOQ could not be determined. These data are correlated with the water tests made in the last years, which shows a general decrease of the heavy metal pollution in sea waters. [ABSTRACT FROM AUTHOR]

The invasive species Rapana venosa (Valenciennes, 1846) was reported for the first time at the Romanian Black Sea coast in 1963 (Gomoiu, 1972). Due to the excellent gourmet qualities, rapa whelk population began to be exploited since 2009. At first, during the period from 2009 to 2012 rapa harvesting was done only manually with divers. Since the second half of 2013, with the legalization of the use of beam trawl fishing, a filter-towed gear type (Order no. 1696 of 11/07/2013, Order no. 400 of 2013), economic operators with fishing activities at the Romanian coastline have begun to focus on the acquisition of new vessels with functional technical characteristics (length, engine power) and equipment (fishing facilities) that would facilitate the industrial exploitation of the gastropod R. venosa. The legalization of fishing with beam trawl allowed a significant increase in catches of Rapana, which led to a gradual implementation of changes in the structure of the fishing fleet, such as increasing the number of vessels with lengths over 9 m and equipping existing vessels with fishing equipment / facilities suitable for fishing combined with both stationary fishing gears (fixed nets, guide cages, long lines etc.) and towed filter nets (pelagic trawl, beam trawl etc.). [ABSTRACT FROM AUTHOR]

The Mediterranean horse mackerel Trachurus mediterraneus, (Steindachner, 1868) is one of the most exploited commercial species of the fisheries in the Black Sea basin. Their economic importance and the need of adequate measures for conservation and management of this resource, require more information about their population dynamics. This paper presents results on temporal variations of total length and weight, age composition, growth parameters and sex ratio of the Mediterranean horse mackerel populations, on the Romanian Black Sea coast. Their mean total length was higher in 2018 than in 2017. One and two year old individuals dominated during the period 2017 to 2018. Females dominated in both 2017 (63%) and 2018 (57%). [ABSTRACT FROM AUTHOR]

The purpose of this study is to highlight new aspects regarding the behavior of Engraulis encrasicolus (Linnaeus, 1758) anchovy on the Romanian Black Sea coast, anchovy being one of the most important economically species in the Black Sea riparian countries and with great importance in the trophic chain of the marine ecosystem. Thus, some behavioral aspects in the migration process of anchovy for feeding, reproduction and for wintering are underlined. Different changes were observed in anchovy behavior: the feeding period overlaps with the breeding period, the temperature is a declining factor of the breeding process, the preparation for wintering determine increased levels of lipids. [ABSTRACT FROM AUTHOR]

The right to privacy is guaranteed by numerous international and national legal instruments. But these, not being absolute, may encounter some boundaries. Throughout the article, the author examines the relation between ensuring the national security and the right to privacy. [ABSTRACT FROM AUTHOR]