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A focus of sea turtle management has been reducing bycatch in commercial fisheries, but sustainable harvest for consumption is also an important objective in many nations. Identifying how much different fisheries contribute to turtle mortality could help focus limited management resources. We estimated national scale turtle catches for two fisheries in the Solomon Islands: a small‐scale reef fishery where turtles are caught for food and sale, and an offshore longline fishery where turtles are bycatch. The footprint of the longline fishery spanned the entire exclusive economic zone of the Solomon Islands and was 67 times bigger than the footprint of the small‐scale fishery. The median catch summed across both fisheries was ∼12,000 turtles in 2018, with 85%–97% of that catch in the small‐scale fishery. We suggest that turtle management in the Solomon Islands, a nation with globally significant turtle breeding populations, should focus on sustainable management of small‐scale coastal fisheries. [ABSTRACT FROM AUTHOR]

Male sperm whales (Physeter macrocephalus) are known to interact with and depredate from commercial longline fishing vessels targeting sablefish (Anoplopoma fimbria) in the Gulf of Alaska (GOA). This study aims to better understand their movement patterns and diving behavior in this region, and in relation to depredation behavior. Between 2007 and 2016 a total of 33 satellite tags were deployed on sperm whales interacting with fishing vessels in the eastern GOA. A subset of these tags also collected dive characteristics. We used state space models to interpolate hourly positions from tags and estimate behavioral state from 29 usable tag records, 14 of which had associated dive information. Whales exhibited slower horizontal movement (1.4 km/hr) within GOA waters compared to south of the GOA (5.5 km/hr), indicating tagged whales sped up when they left the region. Behavioral states indicated primarily foraging behavior (82% of locations) in the GOA and primarily transiting behavior (74% of locations) when whales left the GOA. Dive data showed average (± Standard Deviation) maximum dive depths of 396 m (± 166), and dive durations of 32 min (± 9). Generalized additive models indicated that dives were significantly deeper and longer during the daytime than dawn, dusk, or nighttime, and dives were significantly deeper and shorter during quarter moons, when tidal currents are weakest. Maximum dive depth decreased in areas of higher sablefish CPUE, suggesting a potential link between the sablefish fishery and depredation behavior. As seafloor depth increased, up to 800 m, dives became deeper, indicating that whales were likely targeting both bathypelagic and mesopelagic prey. This highlights the importance of the GOA continental slope as a foraging ground for male sperm whales. This enhanced understanding of sperm whale foraging ecology informs management and conservation efforts in high latitude foraging grounds. [ABSTRACT FROM AUTHOR]

Objective: The objectives of this study were to compare population dynamics of Tilefish Lopholatilus chamaeleonticeps before and after the 2010 Deepwater Horizon (DWH) oil spill in the north‐central Gulf of Mexico (GoM) as well as inside and outside the spill area in the western and southwestern GoM (off Mexico). Methods: Due to the availability of prespill samples of Tilefish, we were able to evaluate growth, mortality, and condition factors during two time periods (2000–2009 versus 2011–2017). Samples were derived from commercial landings and research vessel surveys using demersal longline fishing gear. Result: Although some von Bertalanffy growth parameters differed for fish caught before and after the spill within the spill area, confidence limits for predicted growth curves overlapped for ages >10, while predicted growth for ages <10 declined somewhat after the spill. Tilefish grew faster off Mexico than in the northern GoM. Total instantaneous mortality rates (Z), estimated from aggregate multi‐year catch curves, were highest off Mexico (0.39 ± 0.05 SE), lowest in the western GoM outside the spill area (0.21 ± 0.03), and similar before and after the DWH spill within the spill zone (0.32 ± 0.02). Conclusion: Although Z on the stock within the spill area apparently did not change, differences in fishing mortality may have compensated for changes in natural mortality. Because 90% of the fish that were aged after the spill were alive prior to the spill, their accumulated growth history may have masked postspill growth changes. As we are now 14+ years past the 2010 spill, comparisons of population dynamics from samples collected now and in the future may provide a clearer picture of the strength of incoming year‐classes and the long‐term implications of the spill on Tilefish populations. Impact statementAdult Gulf of Mexico Tilefish did not differ in growth or total mortality before versus after the 2010 Deepwater Horizon oil spill. Condition of postspill fish was lower than prespill. Mexican fish grew faster but had lower condition and higher mortality than U.S. fish. Postspill fish analyzed were predominantly born before the spill. [ABSTRACT FROM AUTHOR]

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Flores Sea has a very huge potential for large pelagic fish which is dominated by tuna. However, efforts to predict potential fishing areas are still very limited, especially by using Satellite Remote Sensing Data. The methods generally used are conventional methods which have limitations in terms of data accuracy, area coverage, and efficiency. This study aimed to map the oceanographic conditions of potential fishing zones through the interpretation of Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery and to determine the oceanographic conditions favored by the yellowfin tuna (Thunnus albacares) in the Southern Flores sea. The data collection was conducted directly in the field using longline fishing gear, where the fishing position and catch per trip were categorized as primary data. To analyze the data, the Generalized Additive Model (GAM) using oceanographic parameters (chlorophyll-a, depth, temperature, and salinity) was used. Using the Generalized Additive Model (GAM) with a CED value of 60.40% and an AIC value of 770.8742, the results showed that the sea surface temperature (SST), chlorophyll-a concentration, salinity, and depth are variables that affect fish catch. Oceanographic parameters in the yellowfin tuna fishing potential zone include a temperature range from 28.5 to 29°C, chlorophyll-a concentration of 0.10- 0.14mg/ m2, salinity of 33.7-34ppt, and depth of 3500-1500m, with the largest Zone of Potential Fishing (ZPPI) in September 2023 covering 31,808 km2, with the largest fish catch amounting to 1038kg. [ABSTRACT FROM AUTHOR]

To comprehensively examine the hook depth distribution and influencing factors of tuna longline fishing in Western and Central Pacific Ocean, data collected aboard the vessel "Songhang" from August to October 2021 were analyzed. A combination of Support Vector Regression (SVR) and Generalized Additive Model (GAM) was employed to investigat the distribution of hook depths across different operational parameters and environmental variables. The objective was to elucidate the impact of each factor on hook depth. The results showed that: (1) Among the calculated values of hook depth, Hook No. 1 had the smallest value at (130.03±3.32) m, while Hook No. 8 had the largest value at (363.25±36.52) m. Regarding the measured values, Hook No. 1 had the smallest depth at (130.81±17.94) m, whereas Hook No. 7 exhibited the largest depth at (329.91±54.37) m. (2) The SVR model exhibited varying goodness of fit, with Hook No. 1 displaying the lowest (R²=0.38) and Hook No. 6 demonstrating the highest (R²=0.77) overall fit. The mean squared error (MSE) for training data was smallest for Hook No. 6 (0.138) and lar gest for Hook No. 8 (0.309), while for testing data, it was smallest for Hook No. 4 (0.086) and largest for Hook No. 5 (0.282). (3) GAM analysis reveals that water layer average velocities at 0-64 m and 128-192 m, as well as the casting speed, exhibit the highest correlations with hook depth across all hooks. Following these, water layer average velocities at 64-128 m, 192-256 m, and 256-320 m, along with vessel speed, show significant correlations. However, water layer average velocity at 320-384 m and wind speed demonstrate no significant correlations with hook depth. (4) The average differences between predicted hook depths by SVR and GAM models and the actual measured values are 1.75% and 6.38%, respectively. The predictions from the SVR model align well with the measured values, showing consistent trends with the variation in hook positions, thus demonstrating good agreement. The results of this study will contribute to understanding the distribution pattern of tuna longline fishing hooks in operation, and provide a basic reference for optimizing the performance of longline. [ABSTRACT FROM AUTHOR]

Despite regulations aimed at curbing shark finning and bycatch, shark fishing mortality rates continue to escalate, partly due to unintended consequences of these policies which, along with illegal, unreported, and unregulated fishing and ghost fishing, undermine conservation efforts. The ineffectiveness of current regulations to curb shark mortality highlights the pressing need for reevaluating shark conservation strategies, especially in ecologically sensitive areas. In this context, the debate on enforcing longlining bans in multiple-use marine protected areas, including shark sanctuaries, is intensifying. Some argue for total bans to minimize incidental shark mortalities, while others highlight the socioeconomic importance of longlining, advocating for alternative conservation measures. In 2000, longline fishing was banned in the Galapagos Marine Reserve (GMR) as a precautionary measure to prevent illegal fishing of sharks and bycatch of endangered, threatened, and protected species. After 24 years of enforcement, official and anecdotal evidence indicate that illegal small-scale tuna longlining and ghost fishing are increasing threats across the reserve. This paper provides an overview of the longline fishing controversy within the GMR, incorporating scientific evidence, legal and socioeconomic considerations, and perceptions from the Galapagos small-scale fishing community. We offer novel insights and recommendations for the development of the Galapagos smallscale tuna fishery within an ecosystem approach to fisheries. This approach aims to reconcile conservation goals with the needs of local communities, while also proposing innovative solutions to address the longstanding debate surrounding longlining in the GMR. [ABSTRACT FROM AUTHOR]

To accurately identify the key features influencing the fisheries distribution of Pacific yellowfin tuna, this study analyzed data from 43 longline fishing vessels operated from 2008 to 2019. These vessels operated in the Pacific Ocean region (0° to 30° S; 110° E to 170° W), with a specific focus on 25 features of yellowfin tuna derived from marine environment data. For this purpose, this study opted for the Lasso regression analysis method to select features to predict Pacific yellowfin tuna fishing grounds, exploring the relationship between the catch per unit effort (CPUE) of yellowfin tuna and multiple features. This study reveals that latitude and water temperature at various depths, particularly the sea surface temperature of the preceding and subsequent months and the temperature at depths between 300 and 450 m, are the most significant features influencing CPUE. Additionally, chlorophyll concentration and large-scale climate indices (ONI and NPGIO) also have a notable impact on the distribution of CPUE for yellowfin tuna. Lasso regression effectively identifies features that are significantly correlated with the CPUE of yellowfin tuna, thereby demonstrating superior fit and predictive accuracy in comparison with other models. It provides a suitable methodological approach for selecting fishing ground features of yellowfin tuna in the Pacific Ocean. [ABSTRACT FROM AUTHOR]

The yellowfin tuna represents a significant fishery resource in the Pacific Ocean. Its resource endowment status and spatial variation mechanisms are intricately influenced by marine environments, particularly under varying climate events. Consequently, investigating the spatial variation patterns of dominant environmental factors under diverse climate conditions, and understanding the response of yellowfin tuna catch volume based on the spatial heterogeneity among these environmental factors, presents a formidable challenge. This paper utilizes comprehensive 5°×5° yellowfin tuna longline fishing data and environmental data, including seawater temperature and salinity, published by the Western and Central Pacific Fisheries Commission (WCPFC) and the Inter-American Tropical Tuna Commission (IATTC) for the period 2000–2021 in the Pacific Ocean. In conjunction with the Niño index, a multiscale geographically weighted regression model based on geographically weighted principal component analysis (GWPCA-MGWR) and spatial association between zones (SABZ) is employed for this study. The results indicate the following: (1) The spatial distribution of dominant environmental factors affecting the catch of Pacific yellowfin tuna is primarily divided into two types: seawater temperature dominates in the western Pacific Ocean, while salinity dominates in the eastern Pacific Ocean. When El Niño occurs, the area with seawater temperature as the dominant environmental factor in the western Pacific Ocean further extends eastward, and the water layers where the dominant environmental factors are located develop to deeper depths; when La Niña occurs, there is a clear westward expansion in the area with seawater salinity as the dominant factor in the eastern Pacific Ocean. This change in the spatial distribution pattern of dominant factors is closely related to the movement of the position of the warm pool and cold tongue under ENSO events. (2) The areas with a higher catch of Pacific yellowfin tuna are spatially associated with the dominant environmental factor of mid-deep seawater temperature (105–155 m temperature) to a greater extent than other factors, the highest correlation exceeds 70%, and remain relatively stable under different ENSO events. The formation of this spatial association pattern is related to the vertical movement of yellowfin tuna as affected by subsurface seawater temperature. (3) The GWPCA-MGWR model can fully capture the differences in environmental variability among subregions in the Pacific Ocean under different climatic backgrounds, intuitively reflect the changing areas and influencing boundaries from a macro perspective, and has a relatively accurate prediction on the trend of yellowfin tuna catch in the Pacific Ocean. [ABSTRACT FROM AUTHOR]

Over the last three decades, the advent and the continuous sophistication of telemetry devices have revolutionized our understanding of how pelagic sharks move and exploit their three-dimensional underwater habitat, with implications for management and conservation. In this study, conventional (4,648) and electronic (18) tags were used to assess the horizontal and vertical movements of blue sharks, Prionace glauca, and their vertical overlap with shallow and deep-set longline fishing gears in the southwestern Atlantic Ocean. Results revealed prolonged permanence in the area, large-scale displacements, including trans-equatorial, trans-Atlantic and Indian–Atlantic movements, and high daily displacement rates. Blue sharks showed an extensive use of the water column and considerable variability among and within individuals in vertical behavior, involving normal and reverse diel vertical migrations, surface-oriented behavior, extended use of mesopelagic waters, and occasional extreme dives into bathypelagic waters. Depth distribution appeared unrelated to size or sex but was influenced by the time of day and temperature, with deeper and colder temperatures consistently found during the day. The moon cycle affected the vertical distribution of some sharks but not others. Temperature-depth recorders deployed on hooks, combined with depth distribution from electronic tags, provided insightful information on the species' vertical overlap with shallow- and deep-set longline configurations. Encounterability values were higher during nighttime and lower during daytime for both longline configurations, but were largely affected by the individuals' vertical behavior, highlighting the importance of accounting for environmental conditions besides fishing gear configuration and métiers. This novel information on blue sharks' movements and fishery interactions in the South Atlantic Ocean can inform future management and conservation strategies. [ABSTRACT FROM AUTHOR]

Striped marlin (Tetrapturus audax) is an oceanic pelagic migratory fish. The stock status of striped marlin in the Indian Ocean is now considered to be overfished and subject to overfishing. Quantifying the level of at‐haulback mortality caused by longline fisheries for tuna and tuna‐like species is critical to reducing fishing pressure and protecting the fate of billfish stocks.This study was based on data from 2482 longline fishing operations recorded by Chinese observers in the western Indian Ocean from 2012 to 2019. The dataset includes information on the survival status of 774 striped marlin and their corresponding details. We used a generalized linear model (GLM) to analyse the level of at‐haulback mortality and its potential influencing factors. The results indicate that the distribution of 774 striped marlin had a lower jaw‐fork length (LJFL) range from 130 to 220 cm, and 51.5% of the specimens died at the time of haul‐back. The GLM model revealed that quarter, sea‐surface temperature (SST), hook type, LJFL, chlorophyll (CHL) and longitude had significant effects on at‐haulback condition when the fish were retrieved on board, with the quarter and sea surface temperature having the most significant effects. The interaction term between hook type and LJFL also had a significant effect on at‐haulback mortality, with the model predictions showing that mortality increased with LJFL when using circle hooks but decreased when using Japanese tuna hooks.There has been limited observational analysis of hooking mortality rates for striped marlin, and the present study may provide an important reference for the conservation and management of striped marlin stocks in the Indian Ocean. [ABSTRACT FROM AUTHOR]

This research focuses on international labor migrants who have the least freedom of movement (as they are confined on fishing boats), but who, paradoxically, are apparently the most well traveled fishermen operating in the Pacific Ocean. This anthropological research aims to analyze the patron–client relationship in Honolulu harbor. The research also examines inter-ethnic entanglements and cultural dynamics within the local Hawaiian fishing community. This article is the second of a two-part series: the first article was based on an ethnographic multi-sited study of longline tuna fishing boats fishing in the middle of the Pacific Ocean. [ABSTRACT FROM AUTHOR]

Simple Summary: The Adriatic Sea is a crucial area for sea turtles, with identified hotspots of presence and areas of high risk. This research identifies distinct patterns in seasonal strandings, indicating season-specific abundance and age-specific mortality, particularly in the crucial neritic habitat of the northern Adriatic, whilst emphasizing key areas in Istria, Lošinj, Zadar, and Šibenik. High-density stranding occurrences, linked to factors like population density and tourism, have been observed in these regions. Fishing-induced mortality, collision with vessels, and potential cold stunning emerge as major threats to loggerhead turtles. Post-mortem investigations underscore the age-specific significance of longline fishing gear and vessel collisions in contributing to mortality, emphasizing the need for focused conservation efforts in high-risk areas. Recognizing and addressing mortality hotspots is essential for understanding and mitigating human–turtle interactions in the Adriatic. This study investigates the spatiotemporal trends of loggerhead turtles along the Croatian Adriatic coast by using stranding data and post-mortem analyses. Information on 620 loggerhead turtles (Caretta caretta), collected in the period between 2010 and 2022, has been analysed. Seasonal stranding variations reveal distinct patterns, indicating season-specific abundance and age-specific mortality in different areas, particularly in the key neritic habitat of the northern Adriatic. The analysis identifies four critical areas in the northeast and central Adriatic showing high stranding densities and provides regional managers with a tool with which to effectively conserve and manage this species. Fishing-induced mortality, collision with vessels, and potential cold stunning are identified as major threats to loggerhead turtles. Post-mortem investigations reveal that longline fishing gear and collisions with vessels are significant age-specific mortality contributors, underscoring the need for targeted conservation efforts in high-risk areas. The study acknowledges potential biases in strandings records but highlights the importance of post-mortem investigations in understanding mortality causes. The findings provide valuable insights for improving conservation strategies, emphasizing the importance of focused surveillance and conservation efforts in identified high-risk locations to mitigate human–turtle interactions. [ABSTRACT FROM AUTHOR]

Most biodiversity monitoring globally tends to concentrate on trends in species' populations and ranges rather than on threats and their management. Here we review the estimated impact of threats and the extent to which their management is understood and implemented for all threats to all Australian threatened bird taxa. The assessment reports the situation in 2020 and how this differs from 2010. The most marked finding was that the impact of climate change has increased greatly over the last decade, and now surpasses invasive species as the threat imposing the heaviest threat load. Climate change has driven recent massive population declines from increased temperatures in tropical montane rainforests and from fire. For both direct climate change impacts and fire management, progress in understanding how to relieve the threats has been slow and patchy. Consequently, little effective management has occurred. By comparison, our analysis showed that the single successful campaign to eradicate introduced mammals from Macquarie Island relieved the total threat load on Australian threatened birds by 5%, and more than halved the load on the birds from oceanic islands. Protection or rehabilitation of habitat, particularly on islands, has also delivered measurable benefit as have, in the longer term, controls on longline fishing. Our approach can be used with other taxonomic groups to understand progress in research and management and to allow quantification of potential benefits from proposed actions, such as the national threatened species plan. Climate change is now the biggest threat to Australian threatened birds, but almost no research or management to mitigate this threat has been undertaken. Most successful threatened species management has been on small islands with invasive species eradication, habitat protection and restoration providing substantial benefits. The approach taken can be used to quantify the benefits of both past conservation interventions and potential interventions. Monitoring trends in threat load complements indices assessing trends in population size and extinction risk. [ABSTRACT FROM AUTHOR]

The management and conservation of tuna and other transboundary marine species have to date been limited by an incomplete understanding of the oceanographic, ecological and socioeconomic factors mediating fishery overlap and interactions, and how these factors vary across expansive, open ocean habitats. Despite advances in fisheries monitoring and biologging technology, few attempts have been made to conduct integrated ecological analyses at basin scales relevant to pelagic fisheries and the highly migratory species they target. Here, we use vessel tracking data, archival tags, observer records, and machine learning to examine inter‐ and intra‐annual variability in fisheries overlap (2013–2020) of five pelagic longline fishing fleets with North Pacific albacore tuna (Thunnus alalunga, Scombridae). Although progressive declines in catch and biomass have been observed over the past several decades, the North Pacific albacore is one of the only Pacific tuna stocks primarily targeted by pelagic longlines not currently listed as overfished or experiencing overfishing. We find that fishery overlap varies significantly across time and space as mediated by (1) differences in habitat preferences between juvenile and adult albacore; (2) variation of oceanographic features known to aggregate pelagic biomass; and (3) the different spatial niches targeted by shallow‐set and deep‐set longline fishing gear. These findings may have significant implications for stock assessment in this and other transboundary fishery systems, particularly the reliance on fishery‐dependent data to index abundance. Indeed, we argue that additional consideration of how overlap, catchability, and size selectivity parameters vary over time and space may be required to ensure the development of robust, equitable, and climate‐resilient harvest control rules. [ABSTRACT FROM AUTHOR]

A meta‐analysis of 40 publications totalling 59 experiments was undertaken to review and assess the effects of changing the hook (circle vs. J‐hooks or tuna hooks), bait (fish vs. squid) and leader (wire vs. nylon) type on retention and at‐haulback mortality rates of teleosts (tunas and billfishes), elasmobranchs and sea turtles caught on shallow‐set and deep‐set pelagic longline fisheries.Circle hooks are a promising approach to mitigate the impact of pelagic longline fisheries on sea turtles, as they reduced sea turtle retention rates. The adoption of circle hooks would, however, also lead to a decrease in swordfish retention, the main target species of shallow‐set pelagic longlines.Using fish as bait resulted in lower retention rates of sea turtles, highlighting that option as an additional measure to further mitigate sea turtle bycatch. The bait type had non‐significant effects on sharks, except for blue shark and shortfin mako, for which at‐haulback mortality rates were significantly higher with fish bait.The use of nylon leaders instead of wire leaders could serve as a conservation measure for sharks, as they reduced the retention of blue shark without adversely impacting the catches of swordfish. The results on the effect of the leader material types should, however, be interpreted with caution owing to the limited information available reporting on leader material effects.When considering future research directions, priority should be given to experimental field work on the effects of leader material and on deep‐set longlines. Evaluating the post‐release survival of species should also be a priority. [ABSTRACT FROM AUTHOR]

School cafeterias in the Canary Islands primarily use imported seafood from industrial fishing operations, despite the presence of nearby fishing fleets that use eco-friendly methods. In an effort to reduce fish exports and imports and decrease fuel usage, a project called Ecotunidos was started in 2018 to supply local tuna and other fish to school cafeterias. The initiative aims to improve the eating habits and health of the local population, particularly school children, while also promoting the consumption of fresh, locally sourced food. The project has been successful in several schools and plans to expand to more schools and islands in the future. [Extracted from the article]

The threat of population declines caused by pelagic longline fisheries in the Atlantic has increased the concern to find strategies that minimize the bycatch and mortality of non-target marine animals. Gear modification, such as the use of circle hooks instead of conventional J-hooks, has been identified as an effective bycatch reduction strategy in different pelagic longline fisheries around the world. This study aimed to verify the effectiveness of the use of circle hooks by quantifying catch rates, relative size selectivity, and anatomical hooking position for the most common target species (swordfish, Xiphias gladius, and blue shark, Prionace glauca), and some bycatch species (loggerhead sea turtles, Caretta caretta, and shortfin mako, Isurus oxyrinchus) caught by the Azorean longline fishing fleet. The trial was conducted for five consecutive years (2000–2004) using eight different types of hooks. In general, the blue shark catches using circle hooks were significantly higher compared to J (Mustad 9/0). The circle hooks also showed high probabilities of catching juvenile blue sharks. Conversely, the circle hooks were efficient in reducing the loggerhead sea turtle bycatch and were related to fewer catches of small sea turtle individuals. The use of circle hooks was also associated with reduced swordfish catches compared to J (Mustad 9/0), and the effect of hook types on length at capture was only significant for Circle (L. & P. 18/0—CLP18) and Ringed Tuna (RT). No significant differences were observed comparing hook type to either catch rates or size selectivity for shortfin mako. Additionally, circle hooks were more likely to lodge in the mouth than in deeper anatomical positions, when compared to J (Mustad 9/0), for the four species analysed. The present study demonstrated that the use of circle hooks could mitigate the impact of the pelagic longline fisheries in the Azores by decreasing the bycatch of sea turtles and reducing animal injuries caused by deep hooking. [ABSTRACT FROM AUTHOR]

Conservation of migratory species exhibiting wide‐ranging and multidimensional behaviors is challenged by management efforts that only utilize horizontal movements or produce static spatial–temporal products. For the deep‐diving, critically endangered eastern Pacific leatherback turtle, tools that predict where turtles have high risks of fisheries interactions are urgently needed to prevent further population decline. We incorporated horizontal–vertical movement model results with spatial–temporal kernel density estimates and threat data (gear‐specific fishing) to develop monthly maps of spatial risk. Specifically, we applied multistate hidden Markov models to a biotelemetry data set (n = 28 leatherback tracks, 2004–2007). Tracks with dive information were used to characterize turtle behavior as belonging to 1 of 3 states (transiting, residential with mixed diving, and residential with deep diving). Recent fishing effort data from Global Fishing Watch were integrated with predicted behaviors and monthly space‐use estimates to create maps of relative risk of turtle–fisheries interactions. Drifting (pelagic) longline fishing gear had the highest average monthly fishing effort in the study region, and risk indices showed this gear to also have the greatest potential for high‐risk interactions with turtles in a residential, deep‐diving behavioral state. Monthly relative risk surfaces for all gears and behaviors were added to South Pacific TurtleWatch (SPTW) (https://www.upwell.org/sptw), a dynamic management tool for this leatherback population. These modifications will refine SPTW's capability to provide important predictions of potential high‐risk bycatch areas for turtles undertaking specific behaviors. Our results demonstrate how multidimensional movement data, spatial–temporal density estimates, and threat data can be used to create a unique conservation tool. These methods serve as a framework for incorporating behavior into similar tools for other aquatic, aerial, and terrestrial taxa with multidimensional movement behaviors. [ABSTRACT FROM AUTHOR]

Background: Bycatch mortality in longline fisheries is a major contributor to global declines in shark populations. The duration of time that an animal is hooked and the impacts of hooking on behavior affect the likelihood of mortality. However, limited information exists on the behavior of sharks to longline capture because of difficulties observing hooking events. Using a fortuitous recovery of an archival satellite tag, we describe the movement of an oceanic whitetip shark (Carcharhinus longimanus) and examine the behavior prior to its mortality in response to hooking on a longline. Results: A 1.5 m (fork length) C.longimanus was tagged and released in good condition by a fisheries observer following initial capture on a US longline fishing vessel. After release, the shark resumed normal vertical behavior within 5 h. Over 198 days, the shark undertook wide-ranging movements throughout the Pacific between Samoa, Niue, and Tonga. The shark was hooked by a second longline vessel while conducting routine yo-yo diving between 0 and 120 m depth. For the first hour after being hooked the shark exhibited high swimming activity with rapid vertical movements between 20 and 40 m indicative of an initial struggle against the line. After this, the shark struggled at the surface for approximately 5 h, until it succumbed to exhaustion and died on the line. Conclusion: Fight time has a strong influence on the mortality rates of sharks captured in commercial longline fishing operations. Data obtained from this shark offers further understanding of capture behavior and time to mortality on a longline for C.longimanus which may assist managers as they work on options to reduce mortality rates for this threatened species. [ABSTRACT FROM AUTHOR]

Vasanth, K.; Muthupandi, K.; Naganandhini, V.; Kumar, M.; Krishnan, A.; Patolla, H., and Radhakrishnan, K., 2023. Effect of J-hook shapes on catch rate, efficiency, and hooking position of Needlefish: Evidence from Palk Bay, India. Journal of Coastal Research, 39(5), 933–939. Charlotte (North Carolina), ISSN 0749-0208. The efficiency of different shapes of J hooks No. 11 (nonoffset straight hook, 10° offset kirbed hook, and 10° offset reversed hook) in needlefish longline fishing gears was studied in 24 fishing grounds in Palk Bay, India, from, February to July 2022. A total of 24 fishing trips were conducted for each experimental gear for the comparative study, with 14,400 hooks, with a total catch of 582 fish during the study. The result was that the kirbed hook had the highest percentage composition of the needlefish (37.36%), followed by the reversed hook (31.79%) and the straight hook (30.75%). Further, the overall hooking rate was higher for the kirbed hook than for the straight hook (13.43% vs. 8.60%). Considering the catch rate, the overall catch per unit effort (CPUE; individual/200 hooks) of the kirbed hook was higher (9.08 vs. 7.45) than that of the straight hook, whereas for the straight hook, the CPUE of nontarget species (0.29) was much higher than that of the kirbed hook (0.12). In terms of the targeted species, the Ablennes hians showed the highest CPUE of 3.78 individuals/200 hooks followed by Tylosurus crocodilus crocodilus (1.78), Strongylura strongylura (1.38); the least dominant CPUE was T. choram (0.94). The percentage of hooking position in the jaw was higher in the kirbed hook than that of the straight hook (64.7% vs. 39.1%) and was found lower in the gut system (11.5% vs. 28.5%). Among the three hook shapes tested, the overall performance of the 10° offset kirbed hook was found to be better than the other 10° offset reversed and nonoffset J hook in terms of a higher catch efficiency, hooking rate, CPUE, and hooking position for needlefish (<0.05). [ABSTRACT FROM AUTHOR]

Bait-based remote underwater video (BRUV) systems are effective devices for remotely observing fish and other marine organisms in challenging environments. The development of a long duration (24 h) surface BRUV observation surveys allowed the monitoring of scarce and elusive pelagic sharks and the direct impact on non-targeted species of longline fishing in the Western Mediterranean. Technological limitations, such as the limited storage capacity and a single surface camera, were improved by (i) adding a deep camera equipped with light (below 80 m depth) and (ii) replacing Gopros with a multi-camera video surveillance system (surface and depth) with a storage capacity of several days and access to real-time observation. Based on a deployment effort of 1884 h video data, we identified 11 blue sharks (Prionace glauca) and one bluntnose sixgill shark (Hexanchus griseus), a deep-sea species that scarcely swims at the surface. The real-time observation capability was a powerful tool for reducing logistical costs and for raising environmental awareness in educational and outreach programmes. [ABSTRACT FROM AUTHOR]

Naganandhini, V.; Muthupandi, K.; Vasanth, K.; Neethiselvan, N.; Padmavathy, P., and Radhakrishnan, K., 2023. Influence of hook number on species composition, catch rate, and size of needlefishes in the Gulf of Mannar, India. Journal of Coastal Research, 39(3), 502–508. Charlotte (North Carolina), ISSN 0749-0208. The contribution of needlefishes from the Gulf of Mannar coast has been remarkable and is presently exploited by pelagic longlines. The J hook is extensively used in longline fishing in the Indian region to capture carnivore fishes, including needlefish. Catch rate significantly differed between the hook numbers. In this context, three hook numbers of 10 J, 11 J, and 12 J were studied from January to May 2022. Results showed that the Ablennes hians was the dominant fish caught (47.9%), followed by Tylosurus crocodiles (22.2%), T. choram (16.6%), and Strongylura strongylura (13.3%); weight-based catches of T. crocodiles (39.7%) were dominantly higher, followed by A. hians (35.9%), T. choram (13.8%), and S. strongylura (10.6%). The two-way ANOVA results revealed that a significant (p <0.05) difference occurred between the hook number and the number of species caught. The largest number of fish were caught with hook number 12 (3769), followed by hook number 11 (2745) and hook number 10 (1445). However, the highest weight of 2749.74 kg was recorded with hook number 11 and the lowest of 1602.65 kg in hook number 10 (p <0.05). This is related to fewer fish caught with hook number 10 and heavy fishing pressure on subadults (<50 cm) due to the use of hook number 12. Considering the maximum total length and weight, the optimum hook number for the commercial exploitation of needlefishes was hook number 11. The catch per unit effort disproportionately increased with the increasing of the hook number; the significant higher contribution of 48.25 individuals/1000 hooks was from hook number 12, whereas hook numbers 11 and 10 were 35.13 individuals/1000 hooks and 18.51 individuals/1000 hooks, respectively. [ABSTRACT FROM AUTHOR]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department 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.)

Substantial global population declines in pelagic sharks have led to the introduction of management and conservation measures, including gear restrictions and no‐retention policies, to curb declines and encourage stock recovery. As the rate of discarding sharks increases, there is a growing need to understand prognostic factors that influence their post‐release survival (PRS) outcomes.PRS was measured with survival pop‐up satellite archival tags attached to shortfin mako (Isurus oxyrinchus) and silky sharks (Carcharhinus falciformis) released or discarded from pelagic tuna longline fishing vessels operating in the Western and Central Pacific Fisheries Commission Convention Area. In total, 117 tags were deployed on 60 mako and 57 silky sharks captured as bycatch during commercial pelagic longline fishing trips in New Zealand (n = 35), Fiji (n = 58), New Caledonia (n = 10) and the Republic of the Marshall Islands (n = 14).Mako engaged in long‐distance movements between New Zealand, Australia, Fiji and New Caledonia, while silky sharks tagged in the Marshall Islands showed evidence of seasonal movements eastward.PRS was determined for 110 sharks (57 mako, 53 silky sharks). Most tagged sharks of both species were uninjured (89%) at capture and most sharks (88%) survived post‐release until tag loss or the programmed pop‐up date (60 days). However, when considering a complete fishing interaction (haulback, handling, release), PRS estimates were markedly reduced to 48.6% and 52.3% for mako and silky sharks, respectively. For both species, survivorship was greater in large (>150 cm fork length) uninjured sharks and sharks released with low shark length to trailing branchline ratios.While these findings suggest that retention bans offer sharks an increased chance of survival, continued efforts should be made to improve handling and release practices, reduce trailing gear and minimize pelagic shark bycatch. [ABSTRACT FROM AUTHOR]

Indices of relative abundance directly inform how population abundance changes over time, providing one of the most important pieces of information for a stock assessment. Ideally, indices of abundance should be calculated based on fishery-independent survey data. Survey data are characterized by a spatially random or fixed sampling design, and consistent employment of the same fishing gear and fishing operation across time. However, the unavailability of survey data for most tuna species means that the derivation of abundance indices for these species comes solely from fishery-dependent catch-per-unit-effort (CPUE). We conduct two simulation experiments, based on real fishery-dependent longline data, to quantitatively evaluate the impacts of reduced fishing effort on the standardized longline CPUE for bigeye tuna in the eastern Pacific Ocean. The key findings of the two simulation experiments are 1) a reduced spatial coverage of CPUE data leads to increased bias in the abundance index; 2) the index bias has a minor long-term trend if the reduced spatial coverage of CPUE data is not caused by local depletion; and 3) that bias has a positive long-term trend (i.e., hyper-stable abundance index) if the reduced spatial coverage of CPUE data co-occurs with a local depletion in the abandoned area. This bias, however, can be significantly reduced if the CPUE standardization model includes a temporal correlation structure in spatiotemporal random fields. In addition, the CPUE standardization model provides more realistic estimates of the coefficient of variation of fish abundance when its spatiotemporal random fields are assumed to be correlated in time. This study underscores the necessity of accounting for the temporal correlation structure in spatiotemporal random fields in cases where local depletion and depletion-driven fishery contraction co-occur. [ABSTRACT FROM AUTHOR]

The at-haulback mortality of swordfish (Xiphias gladius), a highly migratory fish, in the Indian Ocean during tuna longline fishery is a concern of the Indian Ocean Tuna Commission Fisheries Management. We obtained the data of 1144 swordfish recorded in 1925 operations in the Indian Ocean by Chinese tuna longline observers from 2012–2018. A generalized linear model was used to analyze the at-haulback mortality of swordfish and the potential influencing factors. The overall mortality rate of swordfish was 64.0%, and the average female size was 166.3 cm (SD = 32.5 cm), with an observed at-haulback mortality rate of 64.3%. The average male size was 155.1 cm (SD = 25.6 cm), which was smaller than females. The observed at-haulback mortality rate was 63.6%. No significant difference was observed between the sexes. Quarter, longitude, hook type, and Lower Jaw-Fork Length (LJFL) had a significant effect on the at-haulback condition when fish were retrieved onboard. Longitude and LJFL had a significant effect on the at-haulback mortality of swordfish. When the capture position was closer to the east, the at-haulback mortality decreased and LJFL increased. The interaction term of hook type and LJFL had a significant effect on at-haulback mortality. When using the circle hook and other hook types, the greater the LFJL, the greater the mortality rate; the opposite was true for Japanese tuna hooks. We provide information for understanding the at-haulback mortality of swordfish bycatch by Chinese tuna longline fishing fleets in the Indian Ocean and its influencing factors, which will help the future conservation and management of swordfish. [ABSTRACT FROM AUTHOR]

Elasmobranchs make up a significant part of bycatch in pelagic longline fisheries, whose induced mortality can be a major threat to endangered species. It is therefore crucial to understand the drivers of at-vessel mortality (AVM) for this fishing gear to enhance postrelease survival. To this end, we analysed scientific data collected during monitored longline fishing experiments conducted in French Polynesia to (i) estimate AVM for each species based on bootstrapped samples and (ii) to assess AVM drivers using multivariate logistic regression models for the blue shark (Prionace glauca) and oceanic whitetip shark (Carcharhinus longimanus). We found that AVM varies widely between species. Oceanic whitetip sharks are more likely to die when caught in waters outside their comfort temperature range, and their odds of survival increase with body length. For the blue shark, the only driver related to AVM is hooking duration. These results indicate that to reduce the AVM of these two species, the vertical distribution of hooks and soak duration should be considered as mitigation measures related to pelagic longlining. [ABSTRACT FROM AUTHOR]

Accounting for spatial and temporal variation in targeting is a concern in many catch per unit effort (CPUE) standardization exercises. In this study we standardized southern bluefin tuna (Thunnus maccoyii, SBT) CPUE from the Korean tuna longline fishery (1996-2018) using generalized linear models (GLMs) with operational set by set data. Data were first explored to investigate the operational characteristics of Korean tuna longline vessels fishing for SBT, such as the spatial and temporal distributions of effort, and changes in the nominal catch rates among major species and species composition. Then we estimated SBT CPUE by area used for the stock assessment in the CCSBT (Commission for the Conservation of Southern Bluefin Tuna) and identified two separate areas in which Korean tuna longline vessels have targeted SBT and albacore tuna (T. alalunga), with targeting patterns varying spatially, seasonally and longer term. We applied two approaches, data selection and cluster analysis of species composition, and compared their ability to address concerns about the changing patterns of targeting through time. Explanatory variables for the GLM analyses were year, month, vessel identifier, fishing location (5° cell), number of hooks, moon phase, and cluster. GLM results for each area suggested that location, year, targeting, and month effects were the principal factors affecting the nominal CPUE. The standardized CPUEs for both areas decreased until the mid-2000s and have shown an increasing trend since that time. [ABSTRACT FROM AUTHOR]

Abundances of large sharks are reported to have declined worldwide, and in response various levels of fisheries management and conservation efforts have been established. For example, marine‐protected areas have been suggested as a means to protect large expanses of ocean from fishing and other industrial activities (e.g., habitat destruction), and in 2011 The Commonwealth of The Bahamas established The Bahamas Shark Sanctuary. Nonetheless, assessing the effectiveness of conservation efforts is challenging because consistent long‐term data sets of shark abundances are often lacking, especially throughout the Caribbean and The Bahamas. In this study, the authors investigated the catch rates and demographics of tiger sharks Galeocerdo cuvier caught in a fishery‐independent survey near Bimini, The Bahamas, from 1984 to 2019 to assess relative abundance trends following the banning of longline fishing in 1993 and the subsequent establishment of the shark sanctuary. To contextualize the relative abundance trends near Bimini, the authors compared this to the relative abundance of tiger sharks in a fishery‐dependent survey from the Southeastern USA (SE USA), conducted from 1994 to 2019. The data of this study suggest that local abundance of tiger sharks has been stable near Bimini since the 1980s, including after the ban of longline fishing and the implementation of the shark sanctuary. In comparison, the abundance near the SE USA has slowly increased in the past decade, following potential declines in the decade preceding the USA Shark Management Plan. The results of this study provide some optimism that current conservation efforts in The Bahamas have been effective to maintain local tiger shark abundance within the protected area. In addition, current fisheries management in the SE USA is allowing this species to recover within those waters. [ABSTRACT FROM AUTHOR]

In the Mediterranean Sea, pelagic longline fisheries, targeting tuna and swordfish, have contributed significantly to the bycatch of threatened chondrichthyan species, such as blue shark (Prionace glauca). The Mediterranean blue shark population is assessed as critically endangered, making a timely implementation of mitigation measures crucial. A comprehensive understanding of blue shark habitat use dynamics is essential for deriving appropriate mitigation measures. This study aimed at evaluating vertical movement behaviour and investigating factors potentially influencing the movements of blue sharks in the Mediterranean Sea. Twenty-six blue sharks, bycaught in a longline fishery in the southern Adriatic, were tagged with pop-up satellite archival tags. Analysis of data from thirteen recovered tags revealed a distinctive diel movement pattern. Blue sharks used shallower waters during the night and deeper waters during the day, characterised by steep ascents and descents during sunset and sunrise, respectively. In addition, lunar phases were also influencing the depth of blue shark movements, with sharks using deeper waters right before and during full-moon. Shark size, salinity, currents, spatial location and time of the year were additional factors influencing blue shark depth use. The observed tendency of blue sharks to use deeper areas at daytime and prior and during the full moon period offers possibilities to develop and test bycatch mitigation strategies. Aligning longline fishing schedules and fishing depths with blue shark behaviour during the fishing seasons could hold promise to effectively reduce spatio-temporal overlap between fishing and blue shark distribution and may ultimately decrease the bycatch impact of the fishery. [ABSTRACT FROM AUTHOR]

Pelagic longline fishing globally raises concerns for adverse interactions with non-target species, prompting the need for sustainable practices and effective mitigation. Adherence to bycatch measures varies globally, driving efforts to find cost-effective alternatives sustaining target species catch while minimizing bycatch. Our study, based in a previous research in southwestern Atlantic Ocean, confirms that fully nocturnal sets (FNS) are more effective in capturing target species (e.g. swordfish, tunas) and reducing bycatch of mako shark and loggerhead turtle compared to partially nocturnal sets (PNS). Extending the analysis to warm and cold seasons, FNS consistently outperforms PNS. In terms of profitability, trips with more FNS are generally more profitable than those with more PNS. Adopting only FNS in pelagic longline fishing seems to be viable, efficient in capturing target species, minimize bycatch, and potentially increasing profits—a promising solution for sustainable and economically viable pelagic longline fishing in southern Brazil. • We compared catches between fully- and partially nocturnal sets (FNS or PNS). • FNS captured more target and less bycatch than PNS for both warm and cold seasons. • Trips focused solely on FNS have the potential to be more profitable compared to PNS. • Forsake trips with PNS may reduce bycatch without affecting fishing incomes. [ABSTRACT FROM AUTHOR]

An empirically estimated harvest function for an off-shore longline fishing vessel is integrated with a demand model for swordfish, and costs. This integrated model is used to examine the economic viability of the conventional pre-trip revenue share scheme between fishing vessel crews and owners, and then to explore optimal fishing efforts to maximise profits. The results demonstrate explicit outcomes of fishing efforts in economic benefits between rational fishing behaviour based on the conventional revenue sharing scheme and optimum fishing efforts to maximise seasonal economic profit. This is due to the trade-off between the quality of landed fish and pursuing more fishing opportunities during a trip. There is a discrepancy between a crew's rational choice of fishing efforts to maximise their share per trip and the vessel owners' preference to maximise seasonal profit. We propose that it is necessary to move from the conventional remuneration scheme to align economic incentives and maximise economic benefits for both vessel crews and owners. [ABSTRACT FROM AUTHOR]

I horridus i on dead compared to partly dead coral, and on sponges vs. live coral vs. coral fragments. Keywords: cold-water corals; Dermechinus horridus; echinoid; ecosystem state shifts; Isididae; longline fishing; octocoral; polyp bailout; resilience; vulnerable marine ecosystem EN cold-water corals Dermechinus horridus echinoid ecosystem state shifts Isididae longline fishing octocoral polyp bailout resilience vulnerable marine ecosystem 1 5 5 02/03/22 20220201 NES 220201 The ability of corals to detach their polyps (leaving behind a naked skeleton) in times of stress, allows polyps to escape from a local source of hostility (Sammarco 1982). In the process, the sea urchins may damage the polyps and stress the colony, which starts to release polyps (bailout) at the tip/base and locations near the sea urchin. Second, it may be a colony stress response to sea urchin perching on the coral branches, leading to polyp bailout. [Extracted from the article]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department 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.)

Despite recent increases in the number of studies that have focused on the movements and habitat use of juvenile and adult white sharks (Carcharodon carcharias) in the Northwest Atlantic Ocean off the eastern United States, there is comparatively little information on the movements of young-of-the-year (YOY) white sharks, particularly in the overwinter season. Simultaneous satellite and acoustic tagging were conducted on YOY white sharks in 2016 and 2017, and data from their first overwinter period (December through April) were analyzed. Tracks of 9 white sharks offer a preliminary characterization of overwinter habitat use. During 2 winter periods over consecutive years, YOY white sharks occupied continental shelf waters (bottom depths: <100 m) off the coasts of North and South Carolina with mean sea-surface temperatures of 14.9-21.2°C, mean sea-surface heights of -0.5-0.2 m, and mean chlorophyll-a concentrations of 0.4-2.8 mg/m³. Their overwinter habitat extended over 950 km south of the current essential fish habitat established for YOY white sharks; however, it did overlap with a seasonal closure area that restricts bottom longline fishing. These results provide preliminary evidence for the existence of an overwinter nursery area for YOY white sharks in U.S. waters of the Atlantic Ocean. [ABSTRACT FROM AUTHOR]

"Save the Albatross" campaign is attempting to educate the industry worldwide with mitigation techniques, but even if the campaign is successful, a third of the world's longline fishing remains illegal and out of control. The fishing industry has identified krill as abundant and offering fatty acids and other nutrients suited to the human diet. People protest stopped this practice, but the fishing industry then blundered forward, switching to longline fishing. [Extracted from the article]

The killer whale (Orcinus orca) behavior termed "depredation" is a major issue negatively affecting fisheries worldwide. Information on killer whale depredation in the northwestern Pacific Ocean is limited. The goal of this work was to assess the extent of killer whale depredation on the groundfish fisheries in the western Bering Sea and the Sea of Okhotsk. Observations of killer whale depredation were conducted on 8 of the 42 (19%) longline fishing vessels between October 2018 and September 2019. Killer whales depredated during 2.0% of vessel days in the western Bering Sea and 18.6% of vessel days in the Sea of Okhotsk, taking exclusively Greenland turbot (Reinhardtius hippoglossoides). Seventy-one killer whales were identified depredating on longlines in the Sea of Okhotsk, with the best estimation for the total number of killer whales depredating about 139 individuals. Results suggest that killer whale depredation is an issue for Greenland turbot longline fisheries in the northwestern Pacific. There is a strong need for mitigation measures, as this has an economic impact on the fisheries and also affects the killer whale population and associated ecosystems. [ABSTRACT FROM AUTHOR]

Human behavioral ecology, Optimal foraging theory, Human-wildlife conflict, Depredation, Interspecific competition, Ecosystem-based management, Sustainable resource exploitation, Longline fisheries Keywords: Human behavioral ecology; Optimal foraging theory; Human-wildlife conflict; Depredation; Interspecific competition; Ecosystem-based management; Sustainable resource exploitation; Longline fisheries EN Human behavioral ecology Optimal foraging theory Human-wildlife conflict Depredation Interspecific competition Ecosystem-based management Sustainable resource exploitation Longline fisheries 649 653 5 11/11/21 20211001 NES 211001 Introduction Global expansion of the human population has shaped many of Earth's ecosystems. It is therefore curious that marine depredation has not been investigated from this standpoint, despite increasing interactions between fisheries and marine predators over the last 70 years (Gilman et al. [14]; Read [26]) that have particularly impacted the longline fishery, since baits and fish are freely accessible for marine predators. Understanding Human-Wildlife Conflict as an Interspecific Competition Using Human Behavioral Ecology. [Extracted from the article]

Impacts of Patagonian toothfish bottom-set longline fishing on vulnerable marine ecosystems (VMEs) are examined in a licenced fishery and adjacent areas beyond national jurisdiction (ABNJ) lacking fishery management. VME taxa distributions were predicted using MaxEnt and compared to fishing footprints of ABNJ and licenced fleets. The ABNJ fishery footprint was almost twice as large as in licenced waters. Whilst the footprint of low fishing effort (0.0–3.4 h km−2) was similar between areas, footprints of medium (3.4–10.2 h km−2) and high (10.2–45.3 h km−2) fishing effort were 4 and 13 times greater, respectively, in ABNJ. Percent overlap of licenced fishing distribution on VME indicator taxa groups was low (6.45–9.82%) compared to the considerably higher (32.62–61.99%) percentage fishing overlap on VME indicator distribution in ABNJ. Our results show that, despite the main area of VME indicator taxa being found within jurisdictional waters, there are important VME habitats on the adjacent high-seas that are potentially highly impacted by unregulated fishing. This raises concerns regarding the potential for ABNJ fisheries to undermine domestic VME management where VMEs straddle managed areas and areas that are inconsistently managed or unmanaged. Management of VMEs would benefit from strengthening regional high-seas fishing governance and monitoring procedures. [ABSTRACT FROM AUTHOR]

Lightsticks baits are discharged into the ocean after their use in longline fishing. The traditional Brazilian community of Costa dos Coqueiros, Bahia, uses lightsticks as a medicine for rheumatism, vitiligo, and mycoses. It may affect marine life when its content leak into the ocean. This study assessed the toxicity identification and evaluation (TIE) of lightsticks constituents on marine mysids Promysis atlantica. The internal solution was dissolved in seawater with ethanol. The lethal concentration of the contaminant that causes mortality in 50% of the exposed population (LC50) after 3h was 0.001%, demonstrating that lightstick is exceptionally toxic because low concentrations cause mortality to mysids P. atlantica. Due to lightsticks' high toxicity, the TIE baseline was 0.005% SSE (stock solution ethanol), and the selected endpoints were behavior and lethality. The sample submitted to aeration presented a significant reduction (P < 0.05) in toxicity (0.005% SSE) because the volatile compounds caused the toxic effect. The sodium thiosulfate treatment induced an insignificant decrease in toxicity. Thus, a new assay was conducted considering aeration and sodium thiosulfate. This combination reduced lightstick toxicity compared to the baseline lightstick, suggesting that volatile compounds and oxidants were responsible for toxicity; even in low concentrations, lightstick can promote significant behavior changes and deleterious effects. It is recommended to create new mechanisms to inspect fishing vessels, thus avoiding the improper disposal of attractors at sea and common garbage. [ABSTRACT FROM AUTHOR]

Adult male and larva of Gnathia capitellum sp. nov. (Crustacea: Isopoda: Gnathiidae) are described. The specimens were laboratory-reared larvae that infested host fishes collected by longline fishing in a coastal bay of Izu Peninsula and adult males found in dredge samples from shallow water (depth: 11-12 m) of Miura Peninsula, central Japan. Adult males of G. capitellum sp. nov. were easily distinguished from the other species of Gnathia Leach, 1814 from around the world by the small oval head and the inner margin of pylopod without plumose setae. Most other Gnathia species have a large rectangular head and plumose setae present on the article 1 of pylopod. Appearance of the adult male resembles the genus Afrignathia Hadfield and Smit, 2008 rather than Gnathia but Afrignathia has maxilla 1 which is absent in all known male gnathiids in the world including G. capitellum sp. nov. Fish parasitic larva of G. capitellum sp. nov. is also described herein. This larva closely resembles larvae of the genus Gnathia, but can be distinguished from the other Gnathia species by the remarkably oval-shaped basis in pereopods 2-4. [ABSTRACT FROM AUTHOR]