Red Mullet Research Articles

Sinop İli Su Ürünleri Üretiminin Mevcut Durumu ve Türkiye Su Ürünleri Üretimindeki Yeri

In the present study, the production amount in the last five years (2015-2019) of Sinop province, which is located in the Black Sea Region and a significant part of fisheries production is carried out, was evaluated. For this purpose; Sinop Provincial Directorate of Agriculture and Forestry and TUIK (Turkish Statistical Institute) data were used. There are 2.326 commercial fishermen and 444 fishing boats in Sinop province. In the sea area of Sinop, 5 enterprises still produce culture fish in cages. The 2 potential marine culture areas identified in Sinop have an annual production capacity of 32.430 tons (31 enterprises). In addition, 5 bivalves (4.940 tons/year) and 1.000.000 number/year capacity juvenile fish production facilities are at the project stage. The total fisheries production of Sinop Province in 2019 was 34.620,9 tons, and 1.505 tons were obtained from aquaculture. In addition to these, 3.924 tons of fish processing facilities per year, and 35 tons of fish meal and oil processing facilities per year are operated. 66% of sea fish caught in Sinop are anchovy (Engraulis encrasicolus ponticus), 16% sprat (Sprattus sprattus phalericus), 13% horse mackerel (Trachurus trachurus), 3% bluefish (Pomatomus saltatrix) and 2% consists of other species. The most preferred marine fish by the consumers are anchovy (Engraulis encrasicolus ponticus), horse mackerel (Trachurus trachurus), whiting (Merlangus merlangus), red mullet (Mullus barbatus), bluefish (Pomatomus saltatrix), turbot (Psetta maxima) and bonito (Sarda sarda) and sea bream (Sparus aurata), sea bass (Dicentrarchus labrax) and rainbow trout (Oncorhyncus mykiss) are the culture fish species offered for sale throughout the year.

Toutes ces choses bizarres que les gens prennent comme nourriture: Poisson, cancer et consultations à Padoue au début des temps modernes

All the Odd Things People Pick up for Food Fish, Cancer and Paduan Consultations in Early Modern Times In the Therapeutics, to Glaucon, Galen devotes a chapter to “The causes and treatment of cancer and elephantiasis”. As for diet, he writes: “Give rockfish”. This article deals with the dietary recommendations concerning “rockfish” in the consilia relating to “cancer” and which were published in Padua in early modern times. The term “cancer” and the localization of the organs which are affected (breast, uterus, liver, nostril, lip) are explained with reference to the pathophysiological knowledge of the time. Galen’s statement about “rockfish” is specified in his On the Powers of Foods, and the exclusion of other fish is justified by their “viscous” nature. The second part of the article is devoted to this question: was the Paduan dietary regime for the treatment of cancer similar to that prescribed for other diseases? Among the latter are mentioned: arthritis, disturbances linked with the reproductive organs, “stones in the kidneys and in the gall-bladder”, “headache with tinnitus”, etc. Pike, sea bream, red mullet are on the contrary considered to be healthy food.

Pathogenic bacteria load and safety of retail marine fish.

This study was conducted to determine the pathogenic bacteria load of 14 species of marine fish obtained from two suppliers (in Bitlis city, Turkey), which provide fish for fish markets, and to reveal the safety of the marine fish in terms of microbiological quality. The counts of total mesophilic aerobic bacteria (TMAB), Staphylococcus aureus, and Escherichia coli, the presence of Salmonella spp. and Listeria monocytogenes were determined in anchovy, horse mackerel, salmon, red mullet, gilthead seabream, bonito, pilchard, common sole, sand smelt, axillary seabream, seabass, Mediterranean horse mackerel, bluefish, and garpike. It was determined that common sole, axillary seabream, seabass, bluefish and Mediterranean horse mackerel obtained from both suppliers were unacceptable in terms of the counts of TMAB. Twenty-four samples exceeded the critical limit of S. aureus and all the samples were unacceptable according to the critical limit of E. coli. While L. monocytogenes was isolated from 50.0% of the samples, Salmonella spp. was isolated from 39.3% of the samples. These results showed that the pathogenic bacteria load of the analyzed marine fish was quite high and they were unsafe in terms of microbiological quality.

Spatiotemporal and bioecological distribution of four commercial Mullid species in an ultraoligotrophic Mediterranean gulf

This study provides baseline data on the mullid fish assemblages based on their morphometries on a shelf of the most oligotrophic water of the Mediterranean Sea, Antalya Gulf. The distribution of fish abundances, biomasses, total length, sex composition, growth parameters, and ecological fish assemblages was studied along three transects (each had a series of bottom depths of 10, 25, 75, 125, and 200 m) between spring 2014 and winter 2015, representing the winter, spring, summer and autumn seasons. Four different species of the Mullidae family: the red mullet (Mullus barbatus), the striped red mullet (M. surmuletus), the golden-banded goatfish (Upeneus moluccensis) and the Por's goatfish (U. pori) were found and subjected to distributional analyses. Excluding M. surmuletus, all of the mullid fish were commonly and abundantly found. There was a definite depth segregation among their distributions, but no seasonal differences occurred. Mediterranean meadows are attractive areas for mullid species, especially for M. surmelatus. The spatial distributional pattern of U. pori was in complete contrast to that of M. surmuletus. Overall, the females (F) outnumbered the males (M) significantly in space (region and depth) and time (season). The morphometric parameters (length-related and growth parameters) were estimated to increase comparatively from east to west in the Mediterranean Sea. Ecologically, the mullid assemblages depended on the seafloor depth, bottom type (habitat and sedimentary characteristics), water productivity and dissolved oxygen content and salinity, and benthic composition.

Length-Weight Relationships for Fourteen Fish Species Collected by Bottom Trawl From the Eastern Black Sea Coast, Turkey

Length-weight relationships (LWR) were described for fourteen demersal and pelagic fish species; whiting (Merlangius merlangus), red mullet (Mullus barbatus), picarel (Spicara maena), scorpion fish (Scorpaena porcus), anchovy (Engraulis encrasicolus), sprat (Sprattus sprattus), horse mackerel (Trachurus mediterraneus), bluefish (Pomatomus saltatrix), turbot (Scophthalmus maximus), thornback ray (Raja clavata), shore rockling (Gaidropsarus mediterraneus) round goby (Neogobius melanostomus), black goby (Gobius niger) and stargazer (Uranoscopus scaber) caught with bottom trawl (12 mm mesh size) from the Eastern Black Sea. Samples were caught in depths from 10 m up to 60 m between April 2017 and March 2018 at monthly intervals. The minimum and maximum lengths and weights, length-weight relationships, parameters of a and b, ± 95% CI of b, r2, growth type (isometric or allometric) of samples, and statistical analyses of the relationship were determined. Estimates for parameter b of the length–weight relationship ranged between 2.44 and 3.54.

Alternative Fish Species for Nutritional Management of Children with Fish-FPIES-A Clinical Approach.

In the Mediterranean region, fish is a common cause of food protein-induced enterocolitis syndrome (FPIES) in children. No laboratory tests specific to FPIES are available, and oral food challenge (OFC) is the gold standard for its diagnosis and testing for achievement of tolerance. Children with FPIES to fish are usually advised to avoid all fish, regardless of the species. Fish are typically classified into bony and cartilaginous, which are phylogenetically distant species and therefore contain less cross-reacting allergens. The protein β-parvalbumin, considered a pan-allergenic, is found in bony fish, while the non-allergenic α-parvalbumin is commonly found in cartilaginous fish. Based on this difference, as a first step in the therapeutic process of children with FPIES caused by a certain fish in the bony fish category (i.e., hake, cod, perch, sardine, gilthead sea bream, red mullet, sole, megrim, sea bass, anchovy, tuna, swordfish, trout, etc.), an OFC to an alternative from the category of cartilaginous fish is suggested (i.e., blue shark, tope shark, dogfish, monkfish, skate, and ray) and vice versa. Regarding the increased mercury content in some sharks and other large species, the maximum limit imposed by the European Food Safety Authority (EFSA) for weekly mercury intake must be considered. An algorithm for the management of fish-FPIES, including alternative fish species, is proposed.

Biometry of the sagittal otoliths for three demersal fish species from the Eastern Adriatic Sea (Montenegro)

The otolith morphology, biometry and otolith size and fish length relationship of three demersal fish species: red mullet Mullus barbatus, common pandora Pagellus erythrinus and hake Merluccius merluccius were examined. Based on otoliths relative sizes P. erythrinus and M. merluccius have Large otoliths, while M. barbatus has Small sagittal otoliths. The relationships between otolith variables and fish somatic growth were described by a linear function. All relationships were statistically highly significant (p<0.001). Otolith length (OL) was found to be the variable most strongly related to fish size, with 61.2 – 95.3 % of the variability, while otolith weight had the lowest coefficient of determination (r2). No differences were found neither between left and right otoliths, nor between male and female otoliths in these relationships. For all species studied the relationships of otolith length, height and weight against total fish length were all found to have positive allometry, indicating that the accretion of otoliths is relatively faster than increase in fish body size. The shape indices of form factor (FF), roundness (RD), aspect ratio (AR), circularity (C), rectangularity (R) and ellipticity (E) were calculated and the relationships between otolith length (OL) and shape indices were determined.

Marmara Denizi’nde iki demersal balık türünün bakalyaro Merluccius merluccius (Linnaeus, 1758) ve tekir (Mullus surmuletus, Linnaeus, 1758)’in otolit kimyası ve otolit morfolojisi üzerine ön çalışma

Otoliths are calcium carbonate (CaCO3) accumulations. Under the influence of different ecosystems morphological and chemical composition change. In this study, economically important two demersal fish species; European hake Merluccius merluccius (Linnaeus, 1758) and Stripet red mullet (Mullus surmuletus Linnaeus, 1758) was examined. Otoliths (Sagitta) belonging to these two species have been studied both chemically and morphologicall. Morphometric measurements of otoliths (length, mm; width, mm; area, mm2; perimeter, mm) in the sagittal of each species was made by the Leica M125 tri-ocular microscope. In the chemical analysis of otoliths, strontium (Sr), magnesium (Mg) and calcium (Ca) trace element amounts, the ratios of Sr and Mg trace elements to Ca element (Sr/Ca and Mg/Ca) were determined. For the micro-chemical analysis of otoliths ICP-MS was used. The highest magnesium (24.92±9.57 mmol/mol) and strontium (26.17±1.81 mmol/mol) element values were found in the otolith of red mullet. The difference between strontium (Sr) and magnesium (Mg) amounts for two fish species was found to be significant (P<0.05). In addition to it was found that the difference between them in the amount of calcium is significant (P<0.001). The shape indexes of otoliths are significantly different between the two fish species. Especially in terms of roundness (RD) and aspect ratio (AR) (P<0.001). The results of this study provide information about the habitats of two economic importance demersal fish species. Since such studies can give information about the habitat areas of fish species, they are important for tracking stocks, migration routes and sustainable fisheries.

Climate differently influences the genomic patterns of two sympatric marine fish species.

Climate influences population genetic variation in marine species. Capturing these impacts remains challenging for marine fishes which disperse over large geographical scales spanning steep environmental gradients. It requires the extensive spatial sampling of individuals or populations, representative of seascape heterogeneity, combined with a set of highly informative molecular markers capable of revealing climatic-associated genetic variations. We explored how space, dispersal and environment shape the genomic patterns of two sympatric fish species in the Mediterranean Sea, which ranks among the oceanic basins most affected by climate change and human pressure. We hypothesized that the population structure and climate-associated genomic signatures of selection would be stronger in the less mobile species, as restricted gene flow tends to facilitate the fixation of locally adapted alleles. To test our hypothesis, we genotyped two species with contrasting dispersal abilities: the white seabream Diplodus sargus and the striped red mullet Mullus surmuletus. We collected 823 individuals and used genotyping by sequencing (GBS) to detect 8,206 single nucleotide polymorphisms (SNPs) for the seabream and 2,794 for the mullet. For each species, we identified highly differentiated genomic regions (i.e. outliers) and disentangled the relative contribution of space, dispersal and environmental variables (climate, marine primary productivity) on the outliers' genetic structure to test the prevalence of gene flow and local adaptation. We observed contrasting patterns of gene flow and adaptive genetic variation between the two species. The seabream showed a distinct Alboran sea population and panmixia across the Mediterranean Sea. The mullet revealed additional differentiation within the Mediterranean Sea that was significantly correlated to summer and winter temperatures, as well as marine primary productivity. Functional annotation of the climate-associated outlier SNPs then identified candidate genes involved in heat tolerance that could be examined to further predict species' responses to climate change. Our results illustrate the key steps of a comparative seascape genomics study aiming to unravel the evolutionary processes at play in marine species, to better anticipate their response to climate change. Defining population adaptation capacities and environmental niches can then serve to incorporate evolutionary processes into species conservation planning.

A highly contiguous nuclear genome assembly of the mandarinfish Synchiropus splendidus (Syngnathiformes: Callionymidae).

The fish order Syngnathiformes has been referred to as a collection of misfit fishes, comprising commercially important fish such as red mullets as well as the highly diverse seahorses, pipefishes, and seadragons—the well-known family Syngnathidae, with their unique adaptations including male pregnancy. Another ornate member of this order is the species mandarinfish. No less than two types of chromatophores have been discovered in the spectacularly colored mandarinfish: the cyanophore (producing blue color) and the dichromatic cyano-erythrophore (producing blue and red). The phylogenetic position of mandarinfish in Syngnathiformes, and their promise of additional genetic discoveries beyond the chromatophores, made mandarinfish an appealing target for whole-genome sequencing. We used linked sequences to create synthetic long reads, producing a highly contiguous genome assembly for the mandarinfish. The genome assembly comprises 483 Mbp (longest scaffold 29 Mbp), has an N50 of 12 Mbp, and an L50 of 14 scaffolds. The assembly completeness is also high, with 92.6% complete, 4.4% fragmented, and 2.9% missing out of 4584 BUSCO genes found in ray-finned fishes. Outside the family Syngnathidae, the mandarinfish represents one of the most contiguous syngnathiform genome assemblies to date. The mandarinfish genomic resource will likely serve as a high-quality outgroup to syngnathid fish, and furthermore for research on the genomic underpinnings of the evolution of novel pigmentation.

Assessment of seasonal relationship between polycyclic aromatic hydrocarbon accumulation and expression patterns of oxidative stress-related genes in muscle tissues of red mullet (M. barbatus) from the Northern Adriatic Sea

In this study, we examined the seasonal association between Polycyclic Aromatic Hydrocarbon (PAH) concentrations and mRNA expression profiles of some antioxidant genes (i.e. CAT, GST and SOD), as well as lipid peroxidation (LPO), in muscle of sexually inactive females of red mullet (Mullus barbatus). Fish were captured in a fishery area of the Northern Adriatic Sea during both winter and summer. We found significantly (p < 0.05) higher ∑HMW-PAHs concentrations in muscle of specimens caught during winter than summer. On the basis of sampling season, red mullets exhibited different gene expression profiles of antioxidant enzymes showing lower levels of both CAT and GST in winter than in summer. Accordingly, CAT was found to be negatively associated with ∑PAH concentrations, especially ∑LMW-PAH, in individuals collected during winter. Seasonal-related downregulation of some oxidative stress biomarker expression is suggestive of greater susceptibility of red mullets to PAHs during winter.

Microplastics in Tissues (Brain, Gill, Muscle and Gastrointestinal) of Mullus barbatus and Alosa immaculata.

The researches on MPs in commercial marine fish are very limited although in marine environments microplastic (MPs) pollution is a global problem. In this study, the presence, composition, and characterization of MPs in different tissues (brain, gill, muscle, and gastrointestinal tract) of commercial fish species [red mullet (Mullus barbatus) and pontic shad (Alosa immaculata Bennett 1835)] from the Black Sea were investigated. M. barbatus (demersal) and A. immaculata (pelagic) fish were preferred in the selection of fish species in order to represent demersal and pelagic environments. After dissected the fish, MPs were obtained from the tissues by extraction using the flotation method; then the MPs were counted and categorized according to shape, size, and color. The composition of the MPs was determined via ATR-FTIR spectroscopy. In terms of microplastic abundance in fish tissues, the gastrointestinal tract (40.0%) ranked first in both fish species, while the lowest MPs density was determined in brain tissues (7.0%). After the gastrointestinal tissue, gills were identified as the second tissue with the highest MPs density. Regardless of fish species, MPs characterization was mainly fibrous (51.0%), black colored (49.0%), and 50-200µm in size (55.0%). Among the nine different polymers determined, polychloroprene (18.8%) and polyamide (15.0%) were found most frequently. This research provides data for tissue-based assessment of MPs in fish. The obtained data showed that MPs (one of the anthropogenic pollutants) are quite high in all tissues regardless of fish species. Moreover, it has emerged that these two fish species are suitable for monitoring microplastics in the study area.

Fishing under climate change: Dynamics of composition and structure of catches in the Russian Black Sea in the XXI century

Currently, the Black Sea ecosystem is undergoing significant changes, and that affects the dynamics of the species composition of catches. The main reasons for the change in the Black Sea ichthyofauna are considered to be: fishing, anthropogenic water pollution, invasion of new species, and the effect of large-scale climatic and related oceanological and hydrological processes on the productivity characteristics of commercial Black Sea fish. With no understanding the patterns of the effect of these factors on ichthyofauna, it is impossible to rationally use bioresources and protect nature. The aim of the work was to study the effect of climate warming on the species composition and structure of catches in the Russian Black Sea in the XXI century. The authors had used: the results of own ichthyological observations; data published on the composition of the Black Sea catches; and the information available on the official websites of the Ministry of Agriculture of the Russian Federation, the Federal Agency for Fishery, and its Sea of Azov – Black Sea Territorial Administration. The analysis of the possible effect of global warming on the results of fishing in the Russian Black Sea was carried out. It is shown that in the XXI century, the ratio of thermophilic fish, which spawn in the summer, increased; those species are European anchovy Engraulis encrasicolus (Linnaeus, 1758), red mullet Mullus barbatus Linnaeus, 1758, and horse mackerel Trachurus mediterraneus (Steindachner, 1868). As established, the dynamics of the ichthyofauna in the area is determined by at least four processes related to water warming: improvement of reproduction conditions and increased survival of eggs and juveniles of thermophilic species; change in the intraspecific structure; invasion and naturalization of Mediterranean species with the subsequent change in the food relationships within the ecosystem; and concentration of psychrophilic species at greater depths. The need for a thorough study of this issue is concluded, aimed at long-term forecasting of the raw material base state of the fishing industry in the Russian Black Sea.

Türkiye’deki barbungiller balıkçılığının TÜİK mikro-veri setine dayalı olarak değerlendirilmesi

Although goatfishes (Mullidae Rafinesque, 1815) are among the most important commercial fishes in Turkey, no research has been found investigating the characteristics and spatial patterns of goatfish fishery. Here, we assessed the goatfish fishery of Turkey based on the microdata set of Turkish National Fishery Statistics gathered by Turkish Statistical Institute (TÜİK) between 2014 and 2017. In this context, we investigated the variation of total goatfish catch by cities. In addition, we compared the contribution of small (boat &lt;10m) and large scale (boat &gt;10m) fishers as well as different fishing techniques to the total goatfish catch in Turkey. Finally, an evaluation was made on the discard rates recorded in the official landing statistics. The results showed that higher red mullet (Mullus barbatus Linnaeus, 1758) catch was reported in the eastern Mediterranean, whereas surmullet (Mullus surmuletus Linnaeus, 1758) catch was significantly higher in the western Black Sea. On the other hand, fishery-independent investigations revealed that the Turkish fishery fleet mostly catches red mullet throughout the coasts of Turkey. Therefore, the separate records of red mullet and surmullet in the landing statistics likely represent the local names of red mullet rather than two different species. Large scale fishers were the main source of fishery pressure in the Mediterranean Sea, the Aegean Sea and the Black Sea. However, the majority of the catch was landed by small scale fishers in the Marmara Sea. The bottom trawl fishery landed 88, 92 and 87% of total goatfish catch in the Black Sea, the Aegean Sea and the Mediterranean Sea, respectively. Purse seiners provided the largest part of total goatfish catch (40%) in the Marmara Sea, where the bottom trawl fishery is prohibited. The overall average for the discard rate was found to be 0.47%. There were no statistically significant differences among the discard rates of two species, marine regions or fishing methods.

Bioeconomic impacts of two simple modifications to trawl nets in the NW Mediterranean

A bioeconomic model was built to assess the contribution of more selective trawl nets to the objectives of the European Multi-Annual Plan for demersal fisheries in the Western Mediterranean (WM MAP). The biological submodel was parameterized with age-structured population parameters for the five target stocks in the WM MAP (European hake, red mullet, deep-water rose shrimp, Nephrops and red shrimp) with a sixth stock combining the remaining commercial by catch and following a biomass dynamics model. The trawl fleet was composed of three fleet segments, according to Vessel Length class (VL1218, VL1824, VL2440), practicing two métiers: coastal mixed demersal fishery and deep-water crustacean fishery. The technological solutions analyzed are two simple technical modifications to the otter bottom trawl and based on i) using a panel of meshes turned 90° (T90) in the extension of the trawl net, and ii) inserting a selective grid built from 40 mm square mesh (SM40) netting into the extension of the trawl net. The Results show that, in terms of policy objectives, the reduction in the values of fishing mortality achieved with these selectivity modifications would be insufficient to reach the target fishing mortality at maximum sustainable yield (Fmsy) prescribed in the WM MAP by 2025. However, model results project a substantial recovery of hake and red mullet stock biomass. The recovery of these two important stocks would help improve the evolution of the economic indicators, resulting generally in higher income, profits and salaries in the short (2025) and mid term (2030).

A population approach for the estimation of methylmercury ToxicoKinetics in red mullets

It is known that, as the vast majority of the anthropogenically emitted mercury can be found in aquatic ecosystems, where several methylating bacteria are present, fish consumption represents the most critical intake source of the most toxic form of mercury, the methylmercury (MeHg).The aim of this work is to predict MeHg levels in the fish muscles which, being the edible portion, are part of the human diet. A physiologically based toxicokinetics model was developed to evaluate the kinetics of MeHg in red mullets. Fishes were described by means of a multi-compartment model including stomach, gut, blood, muscles and an additional compartment virtually encompassing all the remaining organs. Absorption, distribution and excretion were modelled considering different MeHg routes of administration and excretion: intake by ingestion of contaminated food, intake and elimination through inhalation-exhalation and excretion through feces.The model has been firstly validated on Terapon jarbua fish (using the weighted least squares method for parameter estimation) to be subsequently readapted to predict methylmercury concentrations in the muscle of red mullets (using an approximate Bayesian computation approach).This simple multicompartmental model could be considered part, a link in the chain, of a wider more complex project aiming at tracking the fate of MeHg from polluted seawater to the human end consumer. The present study could be useful to surveillance organizations in order to carry out a more comprehensive and informed risk assessment analysis and to take appropriate preventive measures by evaluating possible new MeHg concentration thresholds to minimize public health hazards.

Concentrations of lead, cadmium, and mercury in Mullus barbatus barbatus (L.) from the Algerian coast and health risks associated to its consumption

The Algerian coast receives significant inputs of metallic pollutants. To assess the accumulation of potentially toxic elements (Pb, Cd, Hg) by benthic fish and the consequent health risks for consumers, red mullet specimens (Mullus barbatus barbatus, Linnaeus, 1758) were sampled (n=424) in 3 sites along the Algerian coast (Algiers, Bejaia and Dellys) and analysed for Pb, Cd and Hg in muscles and liver. Spatio-temporal and biological variations were highlighted. The highest concentrations were observed in the liver for the three elements. Mean Pb and Cd concentrations are higher in Algiers specimens. However, the specimens from Dellys are more contaminated by Hg in the liver (0.35±0.0001μg/g). Medium and large specimens show higher concentrations of the three metals. There was no clear seasonal pattern in concentration of Pb, while Hg concentrations are higher in autumn, and Cd in summer, spring and winter. No impact of the three metal elements on Fulton’s K and the hepato-somatic indexes was observed. Despite the average concentrations of Pb and Cd exceeded the recommended regulatory values, few risk related to the consumption of contaminated M. barbatus barbatus inhabiting the Algerian coasts were demonstrated.

Automating fish age estimation combining otolith images and deep learning: The role of multitask learning

Knowledge on the age of fish is vital for assessing the status of fish stocks and proposing management actions to ensure their sustainability. Prevalent methods of fish ageing are based on the readings of otolith images by experts, a process that is often time-consuming and costly. This suggests the need for automatic and cost-effective approaches. Herein, we investigate the feasibility of using deep learning to provide an automatic estimation of fish age from otolith images through a convolutional neural network designed for image analysis. On top of this network, we propose an enhanced - with multitask learning - network to better estimate fish age by introducing as an auxiliary training task the prediction of fish length from otolith images. The proposed approach is applied on a collection of 5027 otolith images of red mullet (Mullus barbatus), considering fish age estimation as a multi-class classification task with six age groups (Age-0, Age-1, Age-2, Age-3, Age-4, Age-5+). Results showed that the network without multitask learning predicted fish age correctly by 64.4 %, attaining high performance for younger age groups (Age-0 and Age-1, F1 score > 0.8) and moderate performance for older age groups (Age-2 to Age-5+, F1 score: 0.50−0.54). The network with multitask learning increased correctness in age prediction reaching 69.2 % and proved efficient to leverage its predictive performance for older age groups (Age-2 to Age-5+, F1 score: 0.57−0.64). Our findings suggest that deep learning has the potential to support the automation of fish age reading, though further research is required to build an operational tool useful in routine fish aging protocols for age reading experts.

Integrated use of condition indexes, genotoxic and cytotoxic biomarkers for assessing pollution effects in fish (Mullus barbatus L., 1758) on the West coast of Algeria

Coastal pollution is a severe threatens to aquatic organisms. The purpose of this study is to evaluate the temporal and spatial variability of the biological responses of Mullus barbatus collected between autumn 2019 and summer 2020 from two impacted areas and a control site, along the Algerian west coast. Besides the condition indexes (gonadosomatic index GSI, hepatoso-matic index HSI and Fulton’s condition factor K), the micronucleus test (MNT) and the neutral red retention time (NRRT) assay were measured in erythro-cytes. The results revealed a significant correlation between the different fish condition indexes, in link with their reproduction cycle at the three sam-pling sites. Also, GSI, HSI and K showed significant differences between the sites (p&lt;0.05), highlighting the fact that the worst environmental conditions occur at the polluted sites in comparison to the reference one. The study of the two biomarkers showed a significant increase (p&lt;0.05) in the frequency of micronuclei (MN) occurrence in the summer period correlated with signifi-cantly (p&lt;0.05) shorter NRRT. In addition, the erythrocytes of M. barbatus populations from the so-called polluted areas presented statistically (p&lt;0.05) higher MN frequencies and shorter NRRT than those of the reference site. This work should contribute to the validation of the use both of the condi-tion indexes (GSI, HSI and K) and the biomarkers (MN and NRRT tests) in bio-monitoring studies of the marine environment since they allowed to deter-mine the level of exposure to the general environmental stress of the investi-gated red mullet populations and, consequently, the quality of their biotope.

Real Power Loss Reduction by Billfish and Red Mullet Optimization Algorithms

In this paper Billfish Optimization Algorithm (BOA) and Red Mullet Optimization (RMO) Algorithm has been designed for voltage stability enhancement and power loss reduction. Electrical Power is one among vital need in the society and also it plays lead role in formation of smart cities. Continuous power supply is essential and mainly quality of the power should be maintained in good mode. In this work real power loss reduction is key objective. Natural hunting actions of Billfish over pilchards are utilized to model the algorithm. Candidate solutions in the projected algorithm are Billfish and population in the exploration space is arbitrarily engendered. Movement of Billfish is high, it will attack the pilchards vigorously and it can’t escape from the attack done by the group of Billfish. Then in this paper Red Mullet Optimization (RMO) Algorithm is proposed to solve optimal reactive power problem. Projected RMO algorithm modeled based on the behavior and characteristics of red mullet. As a group they hunt for the prey and in each group there will be chaser and blocker. When the prey approaches any one of the blocker red mullet then automatically it will turn as new chaser. So roles will interchangeable and very much flexible. At any time chaser will become blocker and any of the blocker will become a chaser with respect to prey position and conditions. Then in that particular area when all the preys are hunted completed then red mullet group will change the area. So there will be flexibility and changing the role quickly with respect to prey position. Alike to that with reference to the fitness function the particle will be chosen as chaser. By means of considering L (voltage stability) - index BOA, and RMO algorithms verified in IEEE 30- bus system. Then without L-index BOA and RMO algorithms is appraised in 30 bus test systems. Both BOA and RMO algorithms condensed the power loss proficiently with improvement in voltage stability and minimization of voltage deviation.