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Ensuring food security in the Anthropocene presents a significant socio-ecological challenge, especially in rapidly changing coastal seascapes that sustain critical fisheries. Herbivorous fishes are essential for food and financial security through fisheries, however, their contributions to regional catches, and the factors influencing them, are not well understood. Analysing reported and reconstructed catch data across 69 Exclusive Economic Zones, we identify shallow-reef area and coastal population density as significant predictors of herbivorous fish catches. However, between-realm (i.e. Indo-Pacific vs. Western Atlantic) differences are marked, with rabbitfishes contributing disproportionately to herbivorous fishery catches. While rabbitfishes have the potential to support productive fisheries due to their relatively faster life-history traits, a 60% decline in catch-per-unit-effort suggests that their production potential, along with parrotfishes and surgeonfishes, may be decreasing globally. Our study highlights contrasting social-ecological outcomes for human populations in the Western Atlantic vs. Indo-Pacific; a difference primarily driven by rabbitfish catches.

Marine fisheries catches have significant economic, social, and cultural importance for coastal communities and nations worldwide. In addition to overfishing and predation, oceanic conditions linked to climate variability profoundly affect catches of oceanic fish species. Based on the fishery data from the Food and Agriculture Organization (FAO) of the United Nations and multiple physical and biogeochemical datasets, we examined the correlation between major modes of climate variability at high and low frequency and multiple key fish species in five major fishing grounds worldwide. The results reveal that over 80% of selected key fish species have declined over the past five decades, with more than 50% transitioning from an increasing to a decreasing trend in the 1990s. Additionally, over 80% of fish species directly correlate with low-frequency climate indices, including Pacific Decadal Oscillation (PDO), Atlantic Multi-decadal Oscillation (AMO) and tropical southern Atlantic (TSA). However, less than 40% of fish species exhibit a direct association with high-frequency climate indices of El Niño Southern Oscillation (ENSO), North Atlantic Ocean (NAO), and Atlantic Niño (ATL3). Synthetic analysis on the Sea Surface Temperature (SST), Mixed Layer Depth (MLD) and chlorophyll a revealed that shifts in the low-frequency climate can directly affect the habitats of numerous fish species, and subsequently influence their fishing yields. Specially, negative SST anomalies and positive chlorophyll-a anomalies were observed during a positive phase of PDO in the central and western Pacific regions, resulting in an increased catch values of Alaska pollock, Pacific sardine, and Chilean jack mackerel. Similar changes occur in positive and negative phases of other low frequency indices. Our research offered a comprehensive perspective on oceanic fish catch responses to climate change, serving as a guide for formulating effective management strategies for marine fish resources.

Abstract—: Data on the first catches of redfin Pseudaspius leptocephalus, yellowfin pufferfish Takifugu xanthopterus, and common dolphinfish Coryphaena hippurus in Sakhalin Bay waters are presented. Other catch locations of Coryphaena hippurus in Sakhalin waters are presented. Issues related to these catches are discussed.

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Simple Summary: Hairtail (Trichiurus lepturus) is a commercially important fish species in South Korea, serving as both a vital food source and a major contributor to the local fishing industry. However, catch rates vary spatially and temporally in response to oceanographic conditions, including water temperature, dissolved oxygen levels, salinity, and food availability. In this study, we investigated the spatial and seasonal distribution of hairtail catches across the southern coastal waters of South Korea. We applied a spatial analytical approach that accounts for both site-specific conditions and the interactions among neighboring areas. Our results indicated that hairtail abundance was positively associated with areas of higher salinity and lower oxygen concentrations. Furthermore, regions with elevated phytoplankton biomass, an essential food source for smaller marine organisms, were found to enhance hairtail presence in adjacent waters. These findings advance our understanding of the species' habitat preferences and environmental responses, providing insights that can inform more effective and sustainable fisheries management strategies. By integrating spatial mapping and environmental data, this research offers critical information for shaping future fishing policies and conserving key fishery resources such as hairtail. This study examined the spatial distribution and environmental determinants of hairtail (Trichiurus lepturus) catch volumes in the southern coastal waters of South Korea, employing a Spatial Durbin Model (SDM) based on grid-level data collected from 2020 to 2022. Key explanatory variables included chlorophyll-a concentration, dissolved oxygen, salinity, sea surface temperature, and fishing effort. Spatial autocorrelation was confirmed through Moran's I test, justifying the application of a spatial econometric framework. Among the environmental factors, salinity exhibited the strongest positive direct effect on catch volumes, whereas dissolved oxygen consistently showed a negative effect. Chlorophyll-a concentration exhibited significant positive effects both within local grids and in neighboring areas. Sea surface temperature also had a modest but significant direct effect on catch volumes. Additionally, higher fishing effort was associated with increased catch volumes, emphasizing the spatial impact of human activities on fishery resources. These findings reveal that hairtail tend to aggregate in high-salinity, low-oxygen environments and respond to seasonal oceanographic variations. Overall, the results highlight the value of spatial econometric models in fisheries research by revealing how environmental and anthropogenic factors influence fish catch through both direct and indirect effects. The spatial framework offers deeper insight into the mechanisms driving hairtail distribution, particularly in ecologically complex regions like the Jeju Strait. [ABSTRACT FROM AUTHOR]

Objective We sought to evaluate the effectiveness of "weak hooks" in reducing the bycatch of Bluefin Tuna Thunnus thynnus in the U.S. Gulf of America (also known as Gulf of Mexico) pelagic longline fishery while maintaining catch rates and size distributions of the primary target species, Yellowfin Tuna T. albacares. Methods A total of 416 experimental pelagic longline sets were conducted aboard commercial vessels in the Gulf of America. Two treatments were compared: a 4.00-mm-diameter circle hook (control) and a custom-made 3.65-mm-diameter circle hook (weak), which were deployed in an alternating fashion. Fish catches and sizes were recorded for each hook type, and catch rates and size distributions were compared statistically. A hook straightening metric was paired with fish fork length for 888 control hooks and 863 weak hooks that caught Yellowfin Tuna. Hook time recorders and time depth recorders were used to estimate escape times for animals that bent weak hooks. Results No significant differences were observed in catch rates between hook types for any of the captured species except Bluefin Tuna, whose catch rates were 46% lower on weak hooks. No differences in size frequency distributions were observed for Yellowfin Tuna between hook types, but larger Bluefin Tuna were caught less frequently on weak hooks. Hook gap widening increased with fish size and was over twice as pronounced for weak hooks compared to control hooks. Approximately 50% of escaped animals that bent weak hooks escaped within 5 min. Conclusions Weak hooks effectively reduced the bycatch of large Bluefin Tuna without significantly affecting the catch rates or size distributions of the primary target species or other encountered species. The increased likelihood of hook straightening on weak hooks suggests a mechanism for selective release of larger Bluefin Tuna, and escape data indicate rapid release for many animals. These results support the use of weak hooks as a tool for reducing bycatch of large Bluefin Tuna and promoting more sustainable fisheries. [ABSTRACT FROM AUTHOR]