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Aiming at the problems of large statistical error and the poor real-time performance of catch weight in the ocean fishing tuna industry, an algorithm based on improved YOLOv8-Pose for albacore tuna (Thunnus alalunga) fork length extraction and weight estimation is proposed, with reference to the human body's pose estimation algorithm. Firstly, a lightweight module constructed using a heavy parameterization technique is used to replace the backbone network, and secondly, a weighted bidirectional feature pyramid network BIFPN is utilized. Finally, the upper and lower jaw and tail feature points of the albacore tuna (Thunnus alalunga) were extracted using the key point detection algorithm, and the weight of the albacore tuna (Thunnus alalunga) was estimated based on the fitted relationship between fork length and weight. The experimental results show that the improved YOLOv8-Pose algorithm reduces the number of model parameters by 13.63% and the number of floating-point operations by 14.03% compared with the baseline model without decreasing the accuracy of the target detection and key point detection and improves the model inference speed by 374%. At the same time, it reduces the drift of the key point detection, and the error of the comparison with the actual albacore tuna (Thunnus alalunga) body weight is not more than 10%. The improved key point detection algorithm has high detection accuracy and inference speed, which provides accurate yield data for pelagic fishing and is expected to solve the existing statistical problems and improve the accuracy and real-time performance of data in the fishing industry. [ABSTRACT FROM AUTHOR]

Microplastic (MP) contamination in seafood, particularly processed varieties like dried and salt-cured fish, poses a significant threat to human health. This study investigated MP levels in 22 salt-cured fish species and commercial sea salts along the Indian east coast. Results showed substantially higher MP concentrations compared to global averages, with fragments and fibres (< 250 µm) composing 70% of identified MPs, primarily PVC and PS polymers (> 55%). Station 2 exhibited high pollution levels, with salt-cured fish averaging 54.06 ± 14.48 MP items/g and salt containing 23.53 ± 4.2 MP items/g, indicating a high hazard risk index. A modest correlation was observed between MP abundance, morphotypes, polymer composition in the salt, and their impact on fish products. Given the critical link between food safety, security, and public health, further research is imperative to mitigate MP contamination, aligning with UN Sustainable Development Goals (Goal 2, Goal 3, Goal 14, and Goal 15) for enhanced food safety and security. [ABSTRACT FROM AUTHOR]

The literature on seawater quality monitoring is increasing, with various systems proposed. This article describes the design of a seawater parameters measuring device and data storage system using a Node MCU ESP8266. This device is designed to be very easy to operate, including for fishermen who catch fish at sea. Three sensors measure seawater parameters: temperature, pH, and salinity. The data obtained from these sensors is sent to the Node MCU ESP8266 and stored first as a solution to the absence of an internet connection at the time of data collection when fishermen catch fish at sea. When connected to the internet network, the data stored in the MicroSD card is sent to the server using the WiFi Module on the Node MCU ESP8266. The data on the server can be accessed via the web. Fishermen operate this device by charging the battery before leaving to catch fish. Arriving at the location to catch fish, fishermen put this device into the water. The device is tied with a rope to the net used by the fisherman or tied to the boat. To motivate fishermen to carry the device, it is also equipped with a fish caller to attract fish to approach the fishing gear. [ABSTRACT FROM AUTHOR]

Copyright of Marine Fisheries: Jurnal Teknologi & Manajemen Perikanan Laut is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Coastal zones, despite their contribution to global economies, continue to suffer the negative impacts of climate variability, which limit the livelihoods of people, particularly small-scale fishermen. This study examined climate variability, coastal livelihoods, and the influence of ocean change on the total annual fish catch in Ghana's Coastal Savannah zone. The mixed-methods approach was used to analyze primary data (semi-structured questionnaires and interviews), secondary data (sea surface temperature (SST) and salinity (SSS), and fish catch), and statistical tests (chi-square, binary logistic regression, and multiple regression). Findings revealed a significant increase in climate variability awareness among fishermen, attributed to the influence of broadcast media. However, they lack sufficient information regarding the transformation of cities, the urbanization process, and its impact on the global climate. Increasing temperatures and sea level rise emerged as the most prevalent impacts of climate variability over the past two decades in the zone. Although the fishermen lack awareness regarding the changes in SSS and their effects on fish, the findings of the multiple regression analysis established that changes in SSS exert a more pronounced effect on the decreasing fishing catch in the zone compared to those in SST. Empirical fish catch records supported the fishermen's claim of a substantial decrease in total fish catch in the zone over the past 20 years. Aside from climate variability impacts, the involvement of many people and light fishing emerged as additional factors contributing to the decreasing fish catch in the zone. High premix fuel prices or shortages and "saiko" activities were the main obstacles that hindered the fishermen's activities. "Saiko" is an unlawful activity in which foreign industrial trawlers sell fish directly to Ghanaian canoes or small-scale fishermen at sea. The fishermen lack sufficient means of supporting their livelihoods, as there is a lack of viable alternative livelihood options. Additionally, the majority of the fishermen experience symptoms of fever and headaches. The binary logistic regression analysis showed that the fishermen's income insufficiency could be substantially reduced if they were to have their own houses, canoes, or fish all year. This situation highlights the need for heightened support from policymakers for improved sustainable livelihood prospects as well as health and well-being. [ABSTRACT FROM AUTHOR]

The global population consumes more seafood from aquaculture today than from capture fisheries and although the aquaculture industry continues to grow, both seafood sectors will continue to be important to the global food supply into the future. As farming continues to expand into ocean systems, understanding how wild populations and fisheries will interact with farms will be increasingly important to informing sustainable ocean planning and management. Using a spatially explicit population and fishing model we simulate several impacts from ocean aquaculture (i.e., aggregation, protection from fishing, and impacts on fitness) to evaluate the mechanisms underlying interactions between aquaculture, wild populations and fisheries. We find that aggregation of species to farms can increase the benefits of protection from fishing that a farm provides and can have greater impacts on more mobile species. Splitting total farm area into smaller farms can benefit fishery catches, whereas larger farms can provide greater ecological benefits through conservation of wild populations. Our results provide clear lessons on how to design and co-manage expanding ocean aquaculture along with wild capture ecosystem management to benefit fisheries or conservation objectives. [ABSTRACT FROM AUTHOR]

As a geographical dimension of justice, spatial justice is characterized by the interplay of social justice and heterogeneous spaces, including the ocean. Despite the generous contribution of ocean to humankind, concerns over aquatic spatial justice are disproportionately lacking. Among the core disruptors of ocean justice, illegal, unreported and unregulated (IUU) fishing imposes a major threat to global fisheries governance. The synthesis of spatial analysis and justice perspective can generate new insights to help understand and potentially address IUU fishing. To examine the spatial (in)justices concerning IUU fishing, we first propose a novel tripartite framework that envisions space as a form of opportunity, society and rights to externalize its socio-environmental implications. Then we integrate productive, distributive and consumptive justices to examine the spatial variations of IUU stakeholders along the fish value chain, and use stakeholder analysis to investigate spatial powers and conflicts regarding both a micro scale of fish communities, and a macro scale of states (coastal state, flag state, port state and market state) and supernational players (regional fisheries management organizations and marine protected areas). It is discovered that certain regions provide greater spatial benefits that stimulate IUU behaviors; IUU misconducts cause spatial differentiation and spatial deprivation that disrupt social orders in fish communities; space can empower stakeholders' inclusive and proper engagement into the place-based management process against IUU fishing. Since the spatialized vision has been increasingly highlighted in marine fisheries management, it is suggested to intervene in the world ocean by leveraging spatial knowledge, managing spatial conflicts and facilitating spatial action, in order to promote spatial justice and better combat IUU fishing globally. [ABSTRACT FROM AUTHOR]

A frightening mucilage event occurred in the Sea of Marmara (SoM) from November 2020 to July 2021, leaving devastating effects on maritime industries, fishing activities, and the benthic ecosystem. The mucilage led to intense fish mortalities, particularly affecting species like smelt, anchovy, and picarel, with severe consequences for benthic ecosystems and various marine species. This study aims to analyze the possible long-term effects of the recent mucilage disaster on species diversity and biomass by assessing the current status of teleost fish assemblages in the SoM. The data set is based on bottom trawl surveys carried out at 52 points at ten stations in the SoM throughout 2023. Data presented through biomass and various ecological indices enabled comparative analyses of changes in fish assemblages pre and postmucilage events. During the study, a total of 5066 kg of retained catch in the 4867 km2 scanned area revealed a biomass of 1040.9 kg·km-2, represented by 45 species in the SoM. Commercial species such as Trachurus trachurus, Merlangius merlangus, Merluccius merluccius stood out with the highest biomass in the teleost fish assemblage. Species richness and total teleost biomass tended to decrease by over 20% in the postmucilage period, reflecting the possible destruction of mucilage to fish populations in the SoM. The decreasing trend in biomass was limited to pelagic species. The extent of the impact on pelagic species may be the cumulative effect of ongoing overexploitation and reduced landing size, as well as intense mortality recorded during the mucilage period. The findings underscore the need for sustainable fishing practices and marine protected areas, including compliance with the Marmara Sea Action Plan, for the restoration and conservation of fish assemblages. [ABSTRACT FROM AUTHOR]

The skin of fish contains a diverse microbiota that has symbiotic functions with the host, facilitating pathogen exclusion, immune system priming, and nutrient degradation. The composition of fish skin microbiomes varies across species and in response to a variety of stressors, however, there has been no systematic analysis across these studies to evaluate how these factors shape fish skin microbiomes. Here, we examined 1922 fish skin microbiomes from 36 studies that included 98 species and nine rearing conditions to investigate associations between fish skin microbiome, fish species, and water physiochemical factors. Proteobacteria, particularly the class Gammaproteobacteria, were present in all marine and freshwater fish skin microbiomes. Acinetobacter, Aeromonas, Ralstonia, Sphingomonas and Flavobacterium were the most abundant genera within freshwater fish skin microbiomes, and Alteromonas, Photobacterium, Pseudoalteromonas, Psychrobacter and Vibrio were the most abundant in saltwater fish. Our results show that different culturing (rearing) environments have a small but significant effect on the skin bacterial community compositions. Water temperature, pH, dissolved oxygen concentration, and salinity significantly correlated with differences in beta-diversity but not necessarily alpha-diversity. To improve study comparability on fish skin microbiomes, we provide recommendations for approaches to the analyses of sequencing data and improve study reproducibility. [ABSTRACT FROM AUTHOR]

Abiotic factors and hydrological disturbances associated with climatic phenomena are challenges to be overcome by many estuarine resident fish. This study investigates whether periods of intense rainfall and continental discharge associated with El Niño events increased the occurrence of estuarine resident fish at adjacent marine sites and possible changes in their body shape and size when caught in the marine area. We used a long-term time series (1996–2019) of environmental factors and abundance of an estuarine resident fish (Atherinella brasiliensis) and comparisons of their body measurements (morphometry) in a subtropical estuary and its adjacent marine zone. Generalized linear models (GLM) showed that A. brasiliensis abundance increased in the marine zone during periods of higher rainfall associated with moderate and very strong El Niño events in relation to neutral and weak events. The species showed differences in body size between estuarine and marine regions, but no substantial changes related to body shape. El Niño events with higher intensity seem to be influencing the displacement of the larger specimens to the marine surf zone over time. More specifically, hydrological disturbance (intense rainfall and river flow) triggered by El Niño of greater intensity might explain the abundance of A. brasiliensis in the marine area and its high tolerance for salinity changes may explain the maintenance outside its estuarine habitat. These findings may help to understand the mechanisms used by estuarine fish to tolerate environmental stress and changes in their habitats, especially in estuaries subject to climatic disturbances caused by El Niño events that are predicted to become more frequent and intense with global warming. Results suggests that long-term changes in flow regimes trigged by strong climatic phenomena like El Niño might alter estuarine specimens' distribution in the Patos Lagoon Estuary. [ABSTRACT FROM AUTHOR]

The presence of potentially harmful metals in commercially available saltwater fish has been extensively documented in scientific literature. This has demonstrated the significance of monitoring the crucial copper (Cu) levels in fish fillets from a perspective focused on human health risks (HHR). This study aimed to evaluate the human health risk (HHR) associated with the presence of Cu in 40 different species of commercial marine fish purchased from Malaysia. The fish samples were gathered from various sources from April to May 2023. The 40 species of commercial marine fish had concentrations of Cu (0.72–82.3 mg/kg dry weight) that fell below acceptable levels defined by seafood safety recommendations. Therefore, these fish are considered good sources of the essential element. The target hazard quotient values for Cu were below 1, suggesting that the hazards of Cu from fish eating are non-carcinogenic. Furthermore, it was discovered that the computed values for the predicted weekly consumption were lower than the defined provisional tolerated weekly intake of Cu. Consuming fish purchased from Malaysia is unlikely to harm consumers' necessary copper intake. However, it is crucial to consistently monitor the safety of consumers who heavily depend on commercially caught marine fish from Malaysia. This monitoring is an essential aspect of implementing environmental, social, and governance (ESG) practices, which industries are concerned about and report on annually. [ABSTRACT FROM AUTHOR]

The present study proposes technological solutions to address the existing limitations by modifying the treatment system to enhance its oxidation potential. The case study focuses on the Magdacesti biological treatment plant, which has encountered a new source of pollution from the "Ocean Fish" factory. Under high loading conditions during the biological treatment stage, both the activated sludge and the biological film, composed of aerobic microorganism flakes, experience changes in their culture composition and lose their sedimentation properties. To overcome these challenges, implementing an anaerobic pre-treatment process and integrating the "Integrated Fixed-Film Activated Sludge" technology into the aerobic process are recommended for intensifying the biological treatment. [ABSTRACT FROM AUTHOR]

Objective: The coexistence of fisheries and offshore wind depends in part on the feasibility of fishing within turbine arrays. This paper explores the value of the Automatic Identification System (AIS) to measure tows of commercial trawl and dredge vessels as quantitative indications of their spatial characteristics to inform offshore wind assessments. Methods: Public records from the AIS provide objective, detailed data supporting the measurement of fishing tows from recent years. Patterns and dimensions were examined from 45 trawl and dredge trips of 35 vessels. Result: Although vessels spread some trips over large areas, they also make multiple passes in swaths as narrow as 0.3 nautical miles (NM). Turns are made by towing the gear through an arc ranging from 0.2 NM to more than 1 NM in diameter or by hauling gear to the boat and turning in less than 0.1 NM. These practices are confirmed by fishing captains. Conclusion: These objective data from actual fishing trips could be valuable in considering the feasibility of fishing in wind farms and planning appropriate layouts. This first effort provides too small a sample to be considered representative, but it may demonstrate the concepts and encourage further research. Techniques could be refined and extended to other regions and activities, as expanding marine interests share limited space. Impact statementOffshore wind power for climate change mitigation must be developed in coexistence with fishing and other ocean uses. The Automatic Identification System provides detailed data on fishing and other activities. We show an application of these data to inform spatial solutions. [ABSTRACT FROM AUTHOR]

Background: Jamaican soil is abundant in heavy metals including mercury (Hg). Due to availability and ease of access, fish is a traditional dietary component in Jamaica and a significant source of Hg exposure. Mercury is a xenobiotic and known neuro-toxicant that affects children's neurodevelopment. Human glutathione S-transferase (GST) genes, including GSTT1, GSTM1, and GSTP1, affect Hg conjugation and elimination mechanisms. Methods: In this exposure assessment study we used data from 375 typically developing (TD) 2–8-year-old Jamaican children to explore the association between environmental Hg exposure, GST genes, and their interaction effects on blood Hg concentrations (BHgCs). We used multivariable general linear models (GLMs). Results: We identified the child's age, consumption of saltwater fish, canned fish (sardine, mackerel), string beans, grain, and starches (pasta, macaroni, noodles) as the environmental factors significantly associated with BHgCs (all P < 0.05). A significant interaction between consumption of canned fish (sardine, mackerel) and GSTP1 in relation to BHgC using either a co-dominant or recessive genetic model (overall interaction P = 0.01 and P < 0.01, respectively) indicated that consumption of canned fish (sardine, mackerel) was significantly associated with higher mean BHgC only among children with the GSTP1 Ile105Val, Ile/Ile [Ratio of mean Hg (95% CI) = 1.59 (1.09, 2.32), P = 0.02] and Ile/Val [Ratio of mean Hg (95% CI) = 1.46 (1.12, 1.91), P = 0.01] genotypes. Conclusions: Since this is the first study from Jamaica to report these findings, replication in other populations is recommended. [ABSTRACT FROM AUTHOR]

Spotted seals, a protected species, face multifaceted threats to their habitat, which in turn impact the closely associated trophic networks. These threats will lead to irreversible structural variations within the ecosystem. Therefore, investigating the topological variability of trophic networks in spotted seals is important. Applying environmental DNA methods, field sample collection was conducted in 2021 during both the sea fishing moratorium period and the fishing period to decode fish diversity. Assessing the current status of fish resources by using the multivariate statistics approach. Applying dietary information establishes the spotted seals' trophic network. Selecting 12 network indexes to analyze the spatiotemporal patterns of network topological attributes. As a result, about 51 families, and 76 genera species were identified. During the sea fishing moratorium and the fishing period, there are 12 and 18 different food resources available for spotted seals, respectively. The diversity index revealed that the FP had greater species richness and diversity than the SP. Comparatively, the Fishing period exhibited higher species richness and biodiversity, likely influenced by habitat heterogeneity and anthropogenic activities. Additionally, the topological features of networks reflected the high clustering coefficients (CC=0.35) and the proportion of omnivorous species (O=60%), indicating that the network structure in this region tends to form higher trophic-level clustering patterns, which facilitate the formation of weaker interactions between clusters, enhancing the robustness of the network. The higher connectivity complexity index during the fishing period (SC=12.3) supported that the spotted seal's trophic network was relatively more stable in this period. Thus, during the fishing period, it is crucial to pay more attention to the intensity of human fishing on mid-to-high trophiclevel omnivorous fish resources to ensure the sustainability of these potential food resources for spotted seals. This comprehensive study achieved three key objectives: (a) utilizing eDNA to characterize fish diversity during distinct periods, (b) establishing trophic networks of spotted seals, and (c) discerning topological attributes and spatiotemporal patterns within the ecological network. Overall, this study can provide technical and data support for integrated ecological network management and propose suggestions for protecting and recovering spotted seals. [ABSTRACT FROM AUTHOR]

Serbia is partially supplied with fish from its own aquaculture and fishing, both commercial and recreational, which averaged 6.70 tons for the period from 2012 to 2021. The majority of fish in the market during the same period came from imports (an average of 34,090 tons). Out of the total catch of fish and fish products on the market in Serbia, 92.80% consisted of marine fish and seafood, while only 7.14% consisted of freshwater fish. The volume of imported sea fish and fish products followed this descending order: hake > tuna > seafood > canned fish > fish fillets > herring > sardines > mackerel > other seafood. Among freshwater fish, trout was the most commonly imported, followed by other species of fish and carp. The average total value of fish imports from 2012 to 2021 was €86.030 million, and the average import price of fish was €2.50/kg. With the import of fish and fish products, and fish from domestic production and catches, the fish market in Serbia was supplied with 41,270 tons of fish during the period studied, which means that the annual per capita fish consumption in Serbia was about 7 kilograms. [ABSTRACT FROM AUTHOR]

Here we report on the reproductive morphology and histology of three Gobiidae species (the Caspian monkey goby, Neogobius pallasi; the Caspian goby, Neogobius caspius; and the round goby, Neogobius melanostomus) from the Iranian coastline of the Caspian Sea. Based on ageing, reproductive histology, and internal and external morphological measures, it appears that all three of these goby species have two types of reproductive males, a large courting, territorial, male type and a small cuckolding parasitic male type, a phenomenon known as alternative reproductive tactics (ART). Although ARTs have been reported previously for one of these species, the round goby, all reports stem from its invasive range; ARTs have never been reported before in any fish species in the Caspian Sea. In all three goby species there was a large, older male type, with a wide head, dark body colouration, and a large investment in accessory glands (AG), an organ important for female attraction and parental care. But there was also a small, light, younger male type, with a narrow head, longer urogenital papilla, and little investment in AGs. The Caspian goby were the largest of the three species, and in this species the smaller, lighter, presumably cuckolding male morph was quite rare (only about 5% of the reproductive male population). In contrast, many of the round goby and monkey goby males were the small, lighter parasitic type, making up nearly half the population of reproductive males (48% and 40%, respectively). Round goby and Caspian goby males had a prominent mesorchial gland, a fibrous sheath of pheromone‐releasing connective tissue that attaches the testes to the dorsal body wall, but all the monkey goby specimens examined lacked this structure. Although ARTs are well documented across fish species and appear to be particularly common in gobies, our study provides the first evidence for ARTs in goby fishes from the Caspian Sea. [ABSTRACT FROM AUTHOR]

Marine fish experience shifts in their distribution due to changes in the physical and biological environments. These shifts pose challenges for fishery businesses and management in international fisheries organizations. In the western and central Pacific Ocean, changes in the spatial distribution of skipjack tuna (Katsuwonus pelamis) due to climate variability often influence fishing activities and economic benefits. This study provides an operational forecast to enhance the decision-making process for fishery managers and fishermen by informing them about fish distributions in the coming months. Monthly forecasts of skipjack tuna habitat are generated utilizing a species distribution model (boosted regression trees) in combination with real-time environmental forecasts. An alternative method (dynamic time warping) is proposed to improve monthly chlorophyll forecasts, which are crucial for enhancing skipjack tuna habitat forecasting. To assess the prediction skills of the model, a retrospective analysis was conducted, forecasting skipjack tuna distribution over 9-month periods and comparing the forecasts with observed occurrences. The results demonstrate that 67.9% of the observed skipjack tuna catches occurred within the forecasted habitats, indicating that the forecast model skillfully predicted skipjack tuna movements 9 months in advance. These monthly updated forecasts can serve as a potential tool for resource managers in developing effective management strategies and fishers in planning fishing operations sustainably and responsibly. [ABSTRACT FROM AUTHOR]

Fish are an important part of the Mediterranean diet, which recommends consuming more fish (at least twice a week) than meat (on a monthly basis). Over the past decade there has been a significant promotion of fish intake because of its high-quality protein content, low fat content, and because it is a good source of vitamins and minerals, but overall because it contains large amounts of omega 3 polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The aim of this study is to determine the fatty acid contents of ten edible wild fish species sold at the Bahrain market along with twelve previously studied edible wild fish species in Bahrain to find out the best of them in terms of EPA, DHA, and n-3/n-6 ratio. Ten edible wild fish species in which their fatty acid contents were not previously studied were selected from the Bahrain market. Lipid extraction and fatty acid methylation were performed. Gas chromatography analysis was conducted to determine the fatty acid compositions of the selected fish species. The result showed significant differences (p < 0.05) in the fatty acid compositions among all ten fish species studied. Edible wild fish species from the present study were given numbers (number 1 is the one with the best fatty acid contents, whereas number 17 is the one with poorest fatty acid contents) based on the sum of EPA and DHA and the n-3/n-6 ratio. The number one fish based on EPA + DHA was Doubleber Bream (Faskir) 26.63 ± 0.30%, while the lowest sum of EPA + DHA was observed in White Sardinella (Oom) 5.45 ± 0.35%. On the other hand, fish with the highest n-3/n-6 ratio is Doubleber Bream (Faskir) with a ratio of 2.62 ± 0.29%, whereas Haffara Bream (Gorgofan) has the lowest ratio 0.60 ± 1.45%. The sum of EPA and DHA and the n-3/n-6 ratio of the 17 fish species from Bahrain were compared with fish species that have high amounts of omega-3 around the world and fish species from the Arabian Gulf Sea and the Mediterranean Sea based on the sum of EPA + DHA and n-3/n-6 ratio. The result has shown that EPA + DHA and the n-3/n-6 ratio were similar to those from the Arabian Gulf Sea but lower in the fish species in Bahrain compared to the Mediterranean Sea and those with high amounts of omega-3 around the world. In conclusion, consuming only wild fish species from Bahrain will not be adequate to gain the recommended daily consumption of 500-1000 mg EPA + DHA. [ABSTRACT FROM AUTHOR]

Copyright of Bozok Veterinary Sciences is the property of Bozok Veterinary Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Central Valley Spring-run Chinook (CVSC) are listed as threatened under the California and federal Endangered Species Acts, but how ocean fisheries affect CVSC is not routinely monitored or managed, largely because of data limitations. Most tag data for CVSC are from a hatchery program that may not sufficiently represent natural-origin fish in ocean and inland fishery recovery data. However, a discontinued tagging program for Butte Creek Wild Spring-run Chinook (BCWSC) provides for estimation of fishery impacts and maturation schedules for a limited set of years, which we compared with estimates for hatchery-origin fish for common years, while extending the hatchery-origin estimates over a wider time-frame. Additional scale-age data from BCWSC allow inferences about more recent maturation rates, conditional on harvest-rate estimates borrowed from other stocks. Overall, CVSC appear to experience low age-3 ocean fishery impact rates, but age-4 impact rates can be comparable to ocean harvest rates estimated for Sacramento River Fall Chinook. Tagging data from the years available indicate that ocean fisheries may reduce spawning run sizes (all ages combined) by 40% to 60% during periods of high fishing effort. Effects of ocean fishing on spawner abundance are weaker in years of reduced fishing or for cohorts displaying earlier maturation. It appears that maturation rates of hatchery-origin CVSC may have increased (i.e., earlier maturation) over the full time-period examined, and there may be indications of increasing maturation rates for BCWSC as well. [ABSTRACT FROM AUTHOR]

Fishing activity generates high amounts of fishing discards, a predictable anthropogenic food subsidies used by seabirds. Although the use of discards by these predators has been well studied, there is a lack of knowledge about the ontogenetic differences in their use. We contributed to filling this gap for the yellow-legged gull (Larus michahellis), an opportunistic predator that extensively exploits anthropogenic food subsides. We investigated its foraging behaviour during the early breeding season deploying GPS devices on adults, immatures, and juveniles from the urban population of Barcelona (northwestern Mediterranean Sea) and examining the effect of fishing vessels on their spatial movements using a Vessel Monitoring System. The results revealed age-related differences in distribution and foraging behaviour at sea and an interaction with fishing vessels in this seabird. Age-related differences in behaviour were explained by the reproductive constraints of adults and the ontogenetic differences associated with lower foraging ability in immature and juvenile individuals. We did not find apparent preferences for a specific type of fishing vessel between ages. These results suggest that the reform of the Common Fisheries Policy might affect the entire population of this species, that could lead to an increase in the use of urban environments, increasing the conflicts with human activities. [ABSTRACT FROM AUTHOR]

The Nizam Zachman Jakarta Ocean Fishing Port (PPSNZJ), the largest fishing port in Indonesia, is currently experiencing overcapacity. This results in ships being moored in rows parallel to berths, indicating the insufficient number of berths in the port. This configuration poses a safety hazard due to the proximity of the moored ships, making it challenging to evacuate them in the event of a fire or other natural disasters. This study was conducted to propose an alternative concept for facility development in urban ocean fishing ports, with PPSNZJ as a study case. The study included a site visit to understand the actual berthing configuration of ships, data collection from the port technical execution unit, and observation of existing fish cargo handling operations. The collected data was analyzed to determine berth capacity and storage productivity, which was used to calculate the number of additional berths required to accommodate loading, unloading, and mooring ships. Based on the design calculations, an alternative development layout is proposed, which fulfils the berth capacity and safety requirements. This study also revealed that the development cost is relatively competitive compared to similar projects. [ABSTRACT FROM AUTHOR]

Cryptocaryoniasis (marine white spot disease), caused by Cryptocaryon irritans, is a major threat to marine fish cultures in tropical and subtropical waters, and a serious nuisance to hobbyists with saltwater fish tanks. With only classical treatment schedules such as copper salts or hyposaline baths being available, control of the disease remains a challenge. In this study, we investigated the effect of Biokos, a viscosin‐like lipopeptide surfactant extracted from a bacterium of the Pseudomonas genus, on the external life stages of C. irritans, including theronts, protomonts and tomonts. The present study demonstrated that the compound has an antiparasitic effect on all tested external stages of the parasite. In particular, when Biokos was used at 48 mg/L, it was able to kill almost all theronts and protomonts within 1 h in in vitro experiments, and using the same concentration in an in vivo challenge experiment, the parasitic load was reduced by more than 95% compared to the control group with no Biokos. Additionally, cultured fish cells were able to proliferate, and fish showed no adverse signs at Biokos concentrations that were effective in killing the parasite. Thus, Biokos may be a promising way for preventing or reducing the burden of this parasitic disease in the future. [ABSTRACT FROM AUTHOR]

In the past two decades, drifting fish aggregation devices (FADs) have revolutionized pelagic fisheries, and are now responsible for the majority of tuna purse seine catches. Here, we argue that by taking advantage of the same proven aggregative properties, FADs could be used to enhance the benefits provided by blue water marine protected areas (MPAs). Using models of commercially targeted fish populations, we explore the potential benefits that could be achieved if unfished conservation FADs—designed as self‐powered devices capable of remaining semi‐stationary—were deployed within blue water MPAs. By increasing the residence time of exploited species in MPAs, conservation FADs will reduce average mortality rates. By increasing the local density of exploited species, they may also improve the function of ecosystems in blue water MPAs. Conservation FADs could, therefore, amplify the benefits of blue water MPAs. We find this amplification is largest in those contexts where blue water MPAs have attracted the most criticism—when their area is small compared to both the open ocean and the distribution of fish stocks that move through them. [ABSTRACT FROM AUTHOR]

The consequences of using 25% whole or shelled sea urchin as an ingredient in anchovy sauce on its fermentation and development of its physicochemical properties after 20 days fermentation was studied. Two varieties of fish and sea urchin sauce were made with or without shell at 1:2:1 ratio (salt:fish:sea urchin) plus a control fish sauce at 1:3 ratio (salt:fish). All sauces were fermented at 40–50 °C for 20 days, where for the first 7 days the preparation remained in a static phase. During their fermentation, pH, salt concentration, aw, TVB-N, TMA, total nitrogen, formaldehyde nitrogen, amino nitrogen, and ammonium nitrogen, as well as aerobic mesophiles and lactic acid bacteria were monitored. The fermentation of the experimental sauces proved to follow an evolution rather similar to the control sauce. The whole and shelled sea urchins provided the necessary microbial and enzymatic load to trigger an adequate hydrolysis of the fish and the production of total nitrogen (16.0–17.6 g/L), formaldehyde nitrogen (15.1–16.0 g/L), and amino nitrogen (0.7–0.8 g/L) of the same order as the control sauce, despite the lower fish content. According to TMA (9.2–13.1 mg N/100 g), VBT (40.0–47.2 mg N/100 g) contents, and pH levels (5.41–5.46), no deviation of the fermentation process was observed under the experimental conditions (salt content, temperature, and agitation after the static phase). Quantitative descriptive analysis (QDA) sensory revealed that the use of sea urchin results in high quality products characterized by their aromas of crustaceans and mollusks. The present study investigates the potential use of shelled and even whole sea urchin as an ingredient for the preparation of high quality fish sauces. [ABSTRACT FROM AUTHOR]

On Caribbean coral reefs, losses of two key groups of grazers, herbivorous fishes and Diadema antillarum, coincided with dramatic increases in macroalgae, which have contributed to decreases in the resilience of these coral reefs and continued low coral cover. In some locations, herbivorous reef fishes and D. antillarum populations have begun to recover, and reductions in macroalgal cover and abundance have followed. Harder to determine, and perhaps more important, are the combined grazing effects of herbivorous fishes and D. antillarum on the structure of macroalgal communities. Surprisingly few studies have examined the feeding preferences of D. antillarum for different macroalgal species, and there have been even fewer comparative studies between these different herbivore types. Accordingly, a series of in-situ and ex-situ feeding assays involving herbivorous fishes and D. antillarum were used to examine feeding preferences. Ten macrophytes representing palatable and chemically and/or structurally defended species were used in these assays, including nine macroalgae, and one seagrass. All species were eaten by at least one of the herbivores tested, although consumption varied greatly. All herbivores consumed significant portions of two red algae species while avoiding Halimeda tuna, which has both chemical and structural defenses. Herbivorous fishes mostly avoided chemically defended species while D. antillarum consumed less of the structurally defended algae. These results suggest complementarity and redundancy in feeding by these different types of herbivores indicating the most effective macroalgal control and subsequent restoration of degraded coral reefs may depend on the recovery of both herbivorous fishes and D. antillarum. [ABSTRACT FROM AUTHOR]

The object of research is the technology of fish products for HELTHY-CAFE with regulated histamine content for the development of health food diets for the population. One of the most problematic places in the technology of food products from raw materials of aquatic origin is microbiological spoilage and, as a result, the formation and accumulation of HisA, which in a certain amount causes a toxic effect. In the course of the study, the methods of isomolar series, sensory analysis, and the study of quality indicators were used. The methodology chosen in the work allows to determine the optimal ratio of hydrocolloids in the system for maximum complexation with histamine in the technology of fish culinary products in gelatin fillings with a harmonious sensory profile and adjustable histamine content. The obtained results of the conducted research allow to state that the proposed method of determining the optimal ratio of sodium alginate and low-esterified pectin substances contributes to the development of a gelatinous filling for fish culinary products in order to ensure the harmonious flavor of ready-made fish dishes and contributes to the expansion of the range of fish products for HELTHY-CAFE with functional and preventive properties. This is due to the fact that taking into account the modern trends in nutrition regarding the safety, functionality, palatability, and attractiveness of fish food products made it possible, based on the method of isomolar series and sensory analysis, to scientifically substantiate the optimal ratio of plant biopolymers, to form requirements for the texture of gelatin filling in fish technology culinary products. On the basis of previous experimental studies, it was shown that the accumulation of histamine occurs more actively in sea fish, which made it possible to substantiate the choice of raw materials for the production of fish culinary products. Taking into account the main global trends in the development of aquaculture, it is proposed to use crucian carp as a raw material, as the main object of aquaculture in Ukraine. The low activity of the peptide hydrolase complex of the muscle tissue of the carp, compared to sea fish, contributes to the formation of a harmonious aromatic profile of fish culinary products, which corresponds to consumer expectations, and the use of natural hydrocolloids of vegetable origin to form a gelatinous structure provides functional properties to the food product and allows controlling the histamine content. [ABSTRACT FROM AUTHOR]

This paper reveals the high demand of fish products in many countries, which subsequently highlighted the high demand of grouper fish species for human consumption. This high demand leads to the insufficient supply of wild ocean grouper fish in the market, thus justifying the need for farmed or cultured grouper fish. Basically, in grouper fish farming, large amounts of trash fish are needed as the feed for grouper fish, which is the carnivorous type of fish. However, since the cost of trash fish is too high, searching for alternative ingredients for the feed through modelling of feed formulation is an option for reducing or minimizing the farming cost. This led to the search for methods in giving the best combination of feedstuff ingredients with appropriate nutrients in formulating the feed. One prospective method is the Evolutionary Algorithm (EA) that has been applied in solving similar problems of diet formulation for several types of animals including livestock, poultry and shrimp. Hence, in this paper, an improved EA method known as the SR-SD-EA is proposed highlighting three important EA operators, which are initialization, selection and mutation. A semi random initialization operator is introduced to filter some important constraints thus increase the chances of obtaining feasible formulations or solutions. Subsequently, the novel selection operator embeds the concept of standard deviation in the SR-SD-EA as part of the function in minimizing the total cost of the formulated grouper fish feed. Eventually, the enhanced boundary-based mutation is also introduced in the algorithm to ensure the crucial constraint of the ingredients' total weight must be met. The overall structure of the SR-SD-EA is presented as a framework, where the three methodological contributions are embedded. The preliminary findings of SR-SD-EA show that the obtained cost computed based on the Best-So-Far feed formulation as the solution is comparable, while all the crucial constraints are fulfilled. [ABSTRACT FROM AUTHOR]

The effects of increased levels of carbon dioxide (CO2) on the Earth's temperature have been known since the end of the 19th century. It was long believed that the oceans' buffering capacity would counteract any effects of dissolved CO2 in marine environments, but during recent decades, many studies have reported detrimental effects of ocean acidification on aquatic organisms. The most prominent effects can be found within the field of behavioural ecology, e.g., complete reversal of predator avoidance behaviour in CO2‐exposed coral reef fish. Some of the studies have been very influential, receiving hundreds of citations over recent years. The results have also been conveyed to policymakers and publicized in prominent media outlets for the general public. Those extreme effects of ocean acidification on fish behaviour have, however, spurred controversy, given that more than a century of research suggests that there are few or no negative effects of elevated CO2 on fish physiology. This is due to sophisticated acid–base regulatory mechanisms that should enable their resilience to near‐future increases in CO2. In addition, an extreme "decline effect" has recently been shown in the literature regarding ocean acidification and fish behaviour, and independent research groups have been unable to replicate some of the most profound effects. Here, the author presents a brief historical overview on the effects of elevated CO2 and ocean acidification on fishes. This historical recap is warranted because earlier work, prior to a recent (c. 10 year) explosion in interest, is often overlooked in today's ocean acidification studies, despite its value to the field. Based on the historical data and the current knowledge status, the author suggests future strategies with the aim to improve research rigour and clarify the understanding of the effects of ocean acidification on fishes. [ABSTRACT FROM AUTHOR]

The spotted grunter Pomadasys commersonnii is an important estuarine-dependent fishery species known to spawn along the east coast (KwaZulu-Natal Province) of South Africa. However, recent evidence suggests that this species also spawns along the southwest coast in the Western Cape Province (WC), which has necessitated the investigation of estuary–sea movements of adult P. commersonnii in the WC, and their link with spawning season and changing environmental conditions. Seasonal gonad maturation of adult P. commersonnii (n = 112) was investigated using histology and the gonadosomatic index. Seven adult P. commersonnii were acoustically tagged and monitored in the Breede Estuary (WC) between November 2016 and March 2020. Tagged individuals spent more time in the estuary (83.5%) than in the adjacent marine environment. Sea trips (n = 90) lasted on average 3.23 (SD 4.55) days (range 1–37 days), with most sea trips (82.6%) having a duration of less than 5 days. The majority of sea trips (>50%) occurred in austral summer, which coincided with the peak spawning season. Increases in estuary water temperatures in summer and river inflow in winter also influenced the presence of tagged fish in the sea. The high degree of residency of P. commersonnii in the Breede Estuary and short sea trips, along with increased frequency of reproductively ripe fish during summer months, supports the conclusion that regional spawning is occurring along the southwest coast. We suggest that management strategies should be put in place to protect the P. commersonnii population along the South African southwest coast, especially during summer, for the recovery of this population. [ABSTRACT FROM AUTHOR]

Understanding the characteristics and conditions that make non-indigenous species (NIS) successful at establishing in recipient communities is a key in determining their potential impacts on native species, as well as to improve management actions such as prevention of future invasions. The round goby (Neogobius melanostomus) is one of the most widespread non-indigenous fish species in the Northern Hemisphere, including the coastal zones of the Baltic Sea. The impacts of round goby in the Baltic Sea are pronounced and multifaceted, yet our knowledge regarding the underlying assembly processes determining its establishment is limited. To overcome this knowledge gap, we applied a trait-based approach to assess the degree of niche overlap and functional (trait) similarity between round goby and native fish species in coastal areas from the Baltic Sea, based on the functional distinctiveness metric. Our results show that round goby is generally quite similar (or not dissimilar) to the native fish of the regional species pool, at least in terms of its overall trait composition. Conversely, round goby demonstrates pronounced differences compared to the native community in its display of parental care and territorial behaviour. Such differences in individual traits could play an important role in round goby's invasion success in the Baltic Sea, including its interactions with native species (e.g. competition). Our results and their potential implications may be highly relevant for conservation and management if integrated within existing risk assessment tools for biological invasions in order to prioritise and enhance the effectiveness of preventative actions towards the expansion of round goby. [ABSTRACT FROM AUTHOR]

The pathways of fresh fish in artisanal fishing: a paradoxical maritime dimension Nowadays fresh sea fish plays a very particular role as an identity marker in the context of the food systems of fishing communities. Given the relationship, continually reiterated by public discourse, between the benefits of its consumption and the paradigm of freshness, we find here a paradoxical intersection with the renewed movement to rediscover Portugal as an oceanic nation. From a holistic, ecological and cultural perspective, we propose here to reveal some moments of the transfiguration of the much-publicized "best fish in the world" along an intricate pathway, from its capture at sea to its presentation as an artisanal product of local origin. That widely reproduced magic motto: "From the sea, straight to your table!" [ABSTRACT FROM AUTHOR]

The use of plastics since they were first mass produced in the 1940s has increased by over 250% owing to their versatility, high durability and low cost. Increased usage with irresponsible disposal and the high molecular weight of plastic that prevents quick and natural degradation has made this versatile material into an environmental hazard that is threatening life both on land and in the oceans. With estimates of more plastics in the ocean than the fish by 2050 under a business-as-usual scenario, marine plastic litter has begun to affect human sustenance. This paper aims to provide a review of the efforts to reduce plastic litter worldwide. [ABSTRACT FROM AUTHOR]

Deep Convolution Neural Networks (DCNNs) can capture discriminative features from large datasets. However, how to incrementally learn new samples without forgetting old ones and recognize novel classes that arise in the dynamically changing world, e.g., classifying newly discovered fish species, remains an open problem. We address an even more challenging and realistic setting of this problem where new class samples are insufficient, i.e., Few-Shot Class-Incremental Learning (FSCIL). Current FSCIL methods augment the training data to alleviate the overfitting of novel classes. By contrast, we propose Filter Bank Networks (FBNs) that augment the learnable filters to capture fine-detailed features for adapting to future new classes. In the forward pass, FBNs augment each convolutional filter to a virtual filter bank containing the canonical one, i.e., itself, and multiple transformed versions. During back-propagation, FBNs explicitly stimulate fine-detailed features to emerge and collectively align all gradients of each filter bank to learn the canonical one. FBNs capture pattern variants that do not yet exist in the pretraining session, thus making it easy to incorporate new classes in the incremental learning phase. Moreover, FBNs introduce model-level prior knowledge to efficiently utilize the limited few-shot data. Extensive experiments on MNIST, CIFAR100, CUB200, andMini-ImageNet datasets show that FBNs consistently outperformthe baseline by a significantmargin, reporting newstate-of-the-art FSCIL results. In addition, we contribute a challenging FSCIL benchmark, Fishshot1K, which contains 8261 underwater images covering 1000 ocean fish species. The code is included in the supplementary materials. [ABSTRACT FROM AUTHOR]

Fish do not change their expressions, unlike humans, making it extremely difficult to know their stress level. However, evaluating the stress response of fish in continuous aquaculture is essential because of their sensitivity to stress. A wireless biosensor system has been developed to easily visualize the stress response by monitoring the glucose level as its indicator. However, the system had a limited range of applicable fish species. The implantation site of the sensor, the interstitial fluid of the eyeball, is hardly found in saltwater fish. In this study, we focused on the implantation of the sensor in abdominal interstitial fluid to expand its range of applicable species. First, we confirmed the presence of glucose in the implantation site and confirmed that the biosensor operated normally even after immersion in the fluid. We also attempted to immerse the biosensor in the abdominal cavity of Nile tilapia (Oreochromis niloticus), then monitored the stress responses. Next, we implanted the biosensor in the abdominal cavity of the saltwater fish horse mackerel (Trachurus japonicus) and obtained some corresponding results, thus demonstrating that the biosensor can also be used in saltwater fish, expanding its application. [ABSTRACT FROM AUTHOR]

Simple Summary: Ocular pathologies, such as cataracts, may affect fish welfare. In severe cataract cases, complications such as anorexia, low body condition score, skin wounds, and scoliosis from chronic abnormal posture may develop in fish. Ultimately, cataracts may be associated with an inability to feed, cachexia, and death. The major surgical treatment of cataracts in fish is lens extraction. Although several cases have been published, little is known regarding the outcome and long-term prognosis of fish undergoing lens extraction. Eleven fish housed in a public aquarium had their lenses extracted after mature cataracts were diagnosed. As lens extraction was bilateral in four cases, follow-ups were available for 15 eyes. Following lens extraction, 73% of the fish resumed feeding, regained a normal body condition score, and appeared clinically normal. Surgical technique and post-operative complications are further detailed in this article. This study reviews the clinical outcome of lens extraction and could help clinicians improve the management of cataracts in fish. Mature cataracts can be a life-threatening condition in fish as it may result in anorexia. Lens extraction has been previously described in fish, but the long-term outcome of this procedure has not been evaluated. Eleven captive-bred adult fish housed in a public aquarium presented with unilateral (n = 3/11) or bilateral (n = 8/11) mature cataracts. All cases belonged to three endangered fish populations: striped bass (Morone saxatilis) originating from the Saint Lawrence River and Atlantic and spotted wolffish (Anarhichas lupus and Anarhichas minor). Pre-operatively, fish presented with anorexia, dark discoloration, abnormal position in the water column, skin abrasions, and/or decreased body condition scores. A lensectomy was performed in eleven fish, including a bilateral procedure in four fish, corresponding to fifteen eyes. Follow-up examinations were performed one to two weeks and one year post surgery. The main complication was self-resolving: corneal edema was present in 67% of eyes, persistent after a week in 47% of eyes, and resolved thereafter. Post-operatively, 73% of fish resumed feeding and regained a good body condition score. Persistent visual impairment post-surgery associated with anorexia required euthanasia in three out of eleven cases. The median time of death was 336 days post surgery (range: 27–1439 days) and three cases were still alive 1334 to 1425 days after the lensectomy. This was considered a favorable outcome for these older individuals with concurrent diseases. [ABSTRACT FROM AUTHOR]