This study aims at quantifying and characterising microplastics (MP) distribution in the water column of the NW Mediterranean Sea as well as MP ingestion by the 2 main planktivorous fish of the area, ...sardine and anchovy.
Debris of similar sizes were found in all water column samples and in all but 2 fish guts (out of 169). MP were found in 93% of water column samples with an average concentration of 0.23 ± 0.20 MP·m−3, but in only 12% of sardines (0.20 ± 0.69 MP·ind−1) and 11% of anchovies (0.11 ± 0.31 MP·ind−1). Fibres were the only shape of MP encountered and polyethylene terephthalate was the main polymer identified in water columns (61%), sardines (71%) and anchovies (89%).
This study confirms the ubiquity of MP in the Mediterranean Sea and imparts low occurrence in fish digestive tracts.
•Microplastics were studied in the NW Mediterranean Sea using 17 stations in 2015.•Microplastic concentration averaged 0.23 ± 0.20 MP·m−3 in the water column.•Microplastic ingestion occurred in only 11–12% of anchovies and sardines.•The main polymer type recovered in each sample was polyethylene terephtalate.•Fibres were the only microplastic shape encountered.
•A total of 4152 E. encrasicolus were obtained from 13 sampling areas in the Mediterranean Sea.•All Anisakis larvae identified by a multilocus approach corresponded to A. pegreffii.•A. pegreffii ...infection rates differed depending on the fishing ground.•Highest levels of the infection were noted in Central and South Adriatic Sea.•Positive correlation between fish length and abundance of A. pegreffii was observed.
European anchovy Engraulis encrasicolus represents one of the principal target species for commercial fishing in Europe. This fish is mostly consumed in different raw dish preparations, which represents a major risk for the fish-borne zoonosis anisakiasis. The present study provides a detailed epidemiological report on ascaridoid larvae in E. encrasicolus from several fishing areas in the Mediterranean basin. Between June 2013 and June 2016, a total of 4152 specimens of E. encrasicolus were obtained from 13 sampling areas. Parasitological analysis was carried out using the UV-press detection method. Anisakis larvae (N=547), identified by diagnostic allozymes and analyses of partial sequences of the EF1 α-1 region of nDNA and mtDNA cox2 gene, corresponded to Anisakis pegreffii. Additionally, sequence analyses of the ITS region of rDNA revealed the presence of Hysterothylacium aduncum larvae.
The levels of infection with A. pegreffii significantly varied between the selected fishing areas. Fish from the Central and South Adriatic Sea showed the highest levels of infection. In contrast, anchovies from Southern Sicily, Ionian and Alboran Seas, were uninfected. A great majority of A. pegreffii larvae (95.8%) were located in the body cavity, whereas only a small percentage of them (4.2%) were detected in the flesh of the fish. A significant positive correlation between fish length and abundance of A. pegreffii was observed. The fish body condition index and infection levels observed in different sampling areas did not correlate significantly. The infection levels by H. aduncum also showed a significantly uneven distribution between different fishing areas of the Mediterranean Sea, and no larval specimens of H. aduncum were detected in examined fish flesh. This study is the first Mediterranean-wide epidemiological assessment of infection in the viscera and flesh of E. encrasicolus by A. pegreffii, an important causative agent of human anisakiasis.
Anisakid nematodes belonging to the species Anisakis pegreffii are distributed in a wide variety of fishes from the Mediterranean Sea and they are known to cause the human zoonosis anisakiasis. The ...present study investigated, for the first time, the response of A. pegreffii larvae (identified to species level by allozymes and mtDNA cox2 sequence analysis) to the storage temperature of European anchovies, Engraulis encrasicolus. The larval motility of A. pegreffii was studied in 1300 fish specimens, captured from a highly infested area (FAO 37.2.1, 43°8′N, 14°16′E), maintained under different temperatures (2 °C, 5 °C, 7 °C), and examined at different time intervals (immediately after fishing, 24 h, 48 h and 72 h). Parasitological analysis was carried out with the UV-press method. The results showed that the increase of infection values with A. pegreffii in the fillets of anchovies was statistically positively related to the increase of the temperature (at 5 °C and 7 °C) and time of storage (after 24 h, 48 h, and 72 h). Accordingly, a significant statistical correlation between the increasing of the worm burden in the fillets and a decreasing of A. pegreffii in the viscera was observed. In contrast, those fish constantly maintained at 2 °C showed no statistically significant variation in infection either in the viscera or the fillets, after 24, 48 and 72 h. In the same batches of anchovies, larvae of the non-zoonotic nematode parasite Hysterothylacium aduncum (identified to the species level by ITS rDNA sequences analysis) were found, but they were never observed infecting the musculature of the anchovies. Our results suggest that temperature plays an important role in the post-mortem motility of A. pegreffii larvae in anchovies. In addition, the presence of A. pegreffii in the fillets inspected immediately after their capture indicates that intra-vitam migration may also occur. As a consequence, the importance of the adoption of rules to prevent human anisakiasis, as the deep freezing to −20 °C for 24 h, was underlined.
•The response by Anisakis pegreffii to storage temperature in anchovies was investigated.•The increase of A. pegreffii larvae in the fish flesh is positively related to the temperature.•The temperature plays a role in the post mortem motility of A. pegreffii larvae in anchovies.•A. pegreffii in the fillets of anchovies can be also the result of intra-vitam migration.
Trace metal contamination in the European sardine and anchovy food web was investigated in the Gulf of Lions, NW Mediterranean Sea, including seawater and size fractions of plankton. The results ...highlighted: i) higher and more variable concentrations in the smaller plankton size classes for all metals except cadmium; ii) higher concentrations in anchovy versus sardine for all elements except lead; iii) different patterns of metal bioaccumulation through the food web: cobalt, nickel, copper, silver, lead and zinc displayed continuously decreasing concentrations (with the exception of increased zinc in fish only), while mercury concentrations dropped considerably in larger plankton size classes and rose significantly in fish. Lastly, cadmium concentrations were found to be highest in intermediate plankton size classes, with very low levels in fish. The need to efficiently characterize the biological composition of plankton in order to fully identify its role in the mobilization and transfer of metals was highlighted.
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•Higher concentrations were generally found in water samples from western stations.•Few or no significant spatial variations were tested or highlighted for biota.•Contrasted bioaccumulation patterns of trace metals along the food web were found.•Concentrations differed greatly among size fractions of plankton.•Anchovy presented higher concentrations than sardine for all metals except Pb.
Modelling the environmental factors influencing the spatial variation of fish early life stages density and their drift history can identify the key biological and physical processes for the ...recruitment variability. Distance-based linear multivariate techniques were used to characterize the spawning areas of the European anchovy Engraulis encrasicolus in the Gulf of Cadiz (GoC). Chlorophyll is the environmental variable that best characterized its spawning areas with a time-lag of three days. The use of Lagrangian models to simulate the dispersal of small pelagic species more dependent on advection such as the European anchovy early life stages (early larvae and eggs) in the GoC could provide the degree of connectivity between spawning and nursery areas and identify the physical drivers of the recruitment variability. The larval final destination is critical for the survival of a marine species which is coastal-dependent during its early life stages. Simulations with a Lagrangian transport model in the Southwest Iberian Peninsula were performed during the most intense spawning peak of 2016, when a strong and persistent countercurrent event developed. Most of the simulated early life stages were transported to the western Portuguese coast and, to a lesser extent, to the Atlantic oligotrophic waters, suggesting an increase in the connectivity between the subdivision 9a South and West components. Although different environmental processes occurring during ontogenetic stages, as well as overfishing, among others, can explain part of the variability observed in recruitment, events such as the development of coastal countercurrents during the spawning season could partly account for an increase of anchovy on the western Portuguese coast and a decrease in the Gulf of Cadiz one year later.
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•The European anchovy spawning areas linked to chlorophyll-a with a lag of 3 days.•Countercurrents (CC) increase larval connectivity between Spanish-Portuguese shelfs.•Westward displacement of spawning contributes to increasing that connectivity.•A small number of early life stages are also exported offshore by CC.
We quantified the incidence of microplastics in the gut contents of the European sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) in the Northwestern Mediterranean Sea and tested ...which variables influence this abundance, including the prevalence of parasites (i.e., trematoda larvae and nematodes). We detected a 58% occurrence of microplastics ingestion in sardines and a 60% in anchovies. With respect to sardines, the individuals with lower body conditions were found to have the highest microplastics ingestion probabilities, whereas in anchovies such probabilities were observed in individuals with higher gonadosomatic indices and smaller size. The areas with the highest microplastics ingestion probabilities were the Gulf of Alicante for sardines and the Gulf of Lion - Ebro Delta for anchovies. Both species showed a positive relationship between parasites and microplastics ingestion. These results highlight that both parasitism and ingestion of microplastics are concerns for the health of marine stocks and human consumers.
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•Ingestion of microplastics was studied for Mediterranean anchovy and sardine.•Occurrence of microplastics ingestion was 58% for sardines and 60% in anchovies.•Microplastics abundance was influenced by latitude and body condition for sardines.•For anchovy the main predictors were gonadosomatic index and total fish length.•Parasite prevalence was positive related with microplastics abundance in both species.
Abstract Most sophisticated stock assessment models often need a large amount of data to assess fish stocks, yet this data is often lacking for most fisheries worldwide, resulting in the increasing ...demand for data-limited stock assessment methods. To estimate fish stock status, one class of these data-limited methods uses simply catch time series data and, in other instances, life history information or fishery characteristics. These catch-only methods (COMs) built differently are known to make assumptions about changes in fishing effort and may perform differently under various fishing scenarios. As a case study, this paper used European anchovy ( Engraulis encrasicolus ) caught in the northwest African waters, though very economically and ecologically important, but still unassessed. Our study investigated the performance of five COMs under different fishing scenarios using as a reference the life-history information of the European anchovy captured in this region of the Atlantic. Hence, the present study developed a simulation approach to evaluate the performance of the five COMs in inferring the stock biomass status (B/B MSY ) with consideration of different fishing scenarios under prior information true to anchovy. All five COMs mostly underestimated B/B MSY throughout the simulation period, especially under constant fishing mortality, and in the last five years of the simulation during all fishing scenarios. Overall, these COMs were generally poor classifiers of stock status, however, the state-space COM (SSCOM) generally performed better than the other COMs as it showed possibilities of recovering an overfished stock. When these methods were explored using actual anchovy catch data collected in the northwest African waters, SSCOM yielded results that were deferred from the other COMs. This study being the first to assess this species’ stock in this area using a suite of COMs, presents more insights into the species stock status, and what needs to be considered before scientifically putting in place management measures of the stock in the area.
Anchovy Engraulis encrasicolus is a good prospect to be developed in the future, maybe it can be used for hyperlipidemia diet. This study, therefore, aims to measure and assess the content of EPA ...(eikosapentaenoat acid) and DHA (docosahexaenoic acid).from Anchovy Engraulis encrasicolus oil extract. The samples were obtained from the city of Kendari in Southeast Sulawesi, Indonesia. It was processed and manufactured at the Halu Oleo University in Pharmacy Laboratory. Furthermore, the extraction process utilized the Soxhlet method, while measuring and analyzing the content of EPA and DHA using UV/Vis Spectropometric. It was found that 25 mg of Anchovy Engraulis encrasicolus oil produced DHA levels of 145,5 mg/g (14,5%) and EPA levels of 97,15 mg/g (7,71%). Anchovy Engraulis encrasicolus is a potential for functional food used to provide protection against diseases associated with metabolic disorders and diet hyperlipidemia.
Many exploited fish and macroinvertebrates that utilize the coastal zone have declined, and the causes of these declines, apart from overfishing, remain largely unresolved. Degradation of essential ...habitats has resulted in habitats that are no longer adequate to fulfil nursery, feeding, or reproductive functions, yet the degree to which coastal habitats are important for exploited species has not been quantified. Thus, we reviewed and synthesized literature on the ecological value of coastal habitats (i.e. seagrass beds, shallow subtidal and intertidal habitats, kelp beds, shallow open water habitats, saltmarshes, mussel beds, macroalgal beds, rocky bottom, and mariculture beds) as feeding grounds, nursery areas, spawning areas, and migration routes of 59 taxa, for which the International Council for the Exploration of the Sea (ICES) gives management advice, and another 12 commercially or ecologically important species. In addition, we provide detailed information on coastal habitat use for plaice (Pleuronectes platessa), cod (Gadus morhua), brown shrimp (Crangon crangon), and European lobster (Homarus gammarus). Collectively, 44% of all ICES species utilized coastal habitats, and these stocks contributed 77% of the commercial landings of ICES-advice species, indicating that coastal habitats are critical to population persistence and fishery yield of ICES species. These findings will aid in defining key habitats for protection and restoration and provide baseline information needed to define knowledge gaps for quantifying the habitat value for exploited fish and invertebrates.
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