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Context: Endangered pelagic thresher sharks (Alopias pelagicus) are facing high fishing pressure in many countries. As the world's largest shark fishing nation, with particularly high catch rates of thresher sharks, the impact of Indonesian fisheries has become a global priority for thresher shark conservation. Therefore, baseline data is needed to inform management and implement international agreements. Aims: This research provides data and management recommendations for data-poor targeted shark fishing in Western Indonesia, where thresher sharks are regularly caught. Methods: Daily landings data was recorded from June 2019 to December 2020 in Southwest Aceh and analysed to explore catch patterns, risk factors for thresher sharks, and potential mitigation options. Key results: Twenty-five wooden vessels of <30 gross tonnage target sharks in the Indian Ocean. We recorded a total of 109 pelagic thresher individuals during the study period, with a female-skewed sex ratio (1 female:0.39 male). Almost all pelagic threshers were caught by the bottom longline. Conclusions: Based on this data, we offer some potential management measures to reduce fisheries impacts on pelagic thresher sharks by applying a simple mitigation hierarchy framework. Implications: These results provide fisheries management recommendations, including effort limits and gear modifications. Pelagic thresher sharks are of conservation priority due to their globally endangered status. This research provides information and recommendations for data-poor fisheries in Indonesia. The results show that fishers use bottom longlines to target sharks in the eastern Indian Ocean. We offer potential management measures to reduce mortality on pelagic threshers by applying a mitigation hierarchy framework. [ABSTRACT FROM AUTHOR]

Participatory decision tools enable stakeholders to reconcile conflicting natural resources management objectives. Fisheries targeting highly productive species can have profound impacts on co-occurring bycatch species with low fecundity and other life history traits that make them vulnerable to anthropogenic sources of mortality. This study developed a decision tool for integrated bycatch management for data-limited to data-rich fisheries, improving upon current piecemeal approaches. First, through a systematic literature review, participants compile a comprehensive database of methods to mitigate the catch and fishing mortality of threatened bycatch species. These mitigation methods are then categorized into tiers of a sequential mitigation hierarchy, where interventions that avoid capture are considered before those that minimize catchability, followed by methods that minimize fishing mortality, before approaches that offset residual impacts. The methods are also assembled within an evidence hierarchy, where findings from meta-analytic modelling studies are more robust and generalizable than from individual studies. The decision tool enables stakeholders to evaluate alternative bycatch management strategies' efficacy at meeting specific and measurable objectives for mitigating the catch and mortality of bycatch and for costs from multispecies conflicts, economic viability, practicality and safety, while accounting for the fishery-specific feasibility of compliance monitoring of alternative bycatch management measures. Ongoing adaptation of the bycatch management framework addresses findings from performance assessments, updated evidence, new mitigation methods and changes to governance systems. The proposed decision tool therefore enables stakeholders to develop bycatch management frameworks that provide precautionary protection for the most vulnerable populations with acceptable tradeoffs. [ABSTRACT FROM AUTHOR]

Many shark and ray (elasmobranch) species are threatened with extinction, due to overfishing and commercial tradeSarawak is situated in Malaysian Borneo in the Coral Triangle: a global priority region for elasmobranch conservation. Malaysia is the world's eighth largest elasmobranch fishing nation, and Sarawak is one of Malaysia's largest fishing states, yet there are limited species‐specific data on catch and trade of elasmobranchs to support conservation and fisheries management decisions.This study presents landing site and market survey data, collected in Sarawak from January 2017 to December 2019. Geographical, temporal and operational trends in volumes of catch and trade are explored; the total volume, value and species composition of Sarawak's local elasmobranch markets is estimated; and simple size‐based indicators are used to assess the sustainability of elasmobranch utilization for several conservation‐priority and frequently traded species, including Critically Endangered and CITES‐listed scalloped hammerhead sharks (Sphyrna lewini) and bottlenose wedgefish (Rhynchobatus australiae).The results conservatively estimate that >26,500 elasmobranchs (~90,000 kg) are locally traded in Sarawak annually, worth ~US$125,000 per year at the market level.Trade is dominated by small to medium‐sized coastal requiem sharks (Carcharhinidae) and stingrays (Dasyatidae), with endangered and CITES‐listed species making up 26% and 32% of total landings and trade, respectively.High proportions of immature individuals were recorded, with evidence of overfishing for several species, based on simple size‐based indicators.Several options are outlined for improving management of elasmobranch fishing and trade in the future, including spatio‐temporal closures and live release protocols, which could help to reduce the mortality of critically endangered species and implement CITES. Such measures could have large conservation impacts with limited socio‐economic cost, since these species make up <5% of the total value of the elasmobranch market. However, management plans need to be co‐designed with full participation of affected coastal communities in order to be ethical and effective. [ABSTRACT FROM AUTHOR]

Sharks are one of the most threatened marine animals, with fishing identified as the prime human activity responsible for population declines. The tropical eastern Pacific, a biogeographic region spanning the coastal areas from Mexico to Peru including the Colombian Pacific coast and the Galapagos archipelago, forms critical habitat and migratory routes for sharks and other marine megafauna. The Colombian government recently announced a total (blanket) ban on all forms of shark fishing in the country, including artisanal and industrial. Prohibiting shark fisheries in Colombia could drive fishing and trade under‐ground, fueling criminality, and marginalization. This will not only undermine recent efforts of local communities and researchers to manage small‐scale fisheries, but will criminalize a key source of income for a historically marginalized part of Colombian society. To be effective and ethical, this government decision needs to be rethought incorporating a more holistic management strategy consented among different stakeholder groups. [ABSTRACT FROM AUTHOR]

Sharks and their cartilaginous relatives are one of the world's most threatened species groups. The primary cause is overfishing in targeted and bycatch fisheries. Reductions in fishing mortality are needed to halt shark population declines. However, this requires complex fisheries management decisions, which often entail trade‐offs between conservation objectives and fisheries objectives. We propose the mitigation hierarchy (MH)—a step‐wise precautionary approach for minimizing the impacts of human activity on biodiversity—as a novel framework for supporting these management decisions. We outline a holistic conceptual model for risks to sharks in fisheries, which includes biophysical, operational and socioeconomic considerations. We then demonstrate how this model, in conjunction with the MH, can support risk‐based least cost shark conservation. Through providing examples from real‐world fishery management problems, we illustrate how the MH can be applied to a range of species, fisheries and contexts, and explore some of the opportunities and challenges hereto. Finally, we outline next steps for research and implementation. This is important in the context of increasing international regulation of shark fishing and trade, which must lead to reductions in shark mortality, while managing trade‐offs between conservation objectives and the socioeconomic value of fisheries. [ABSTRACT FROM AUTHOR]

The blue shark (Prionace glauca) is commonly caught by recreational anglers around the United Kingdom (UK) – part of a population (North Atlantic) which has sustained declines of > 50% over the last three generations (36 years). Therefore, mitigating any detrimental impacts recreational fisheries might have on this species is crucial. This requires understanding anglers' perceptions and behaviours, to co-design appropriate management measures. Here, we explore the socio-cultural relationship between anglers and blue sharks in the UK through structured surveys. A total of seven business operators and 44 recreational anglers responded throughout Aug-Nov 2021. Respondents primarily comprised of over-fifty, educated and wealthy male anglers. A positive relationship was identified: 100% of anglers have respect for sharks; 80% (n = 42) would like their fishing to inform research. We also found that socio-demographic variables correlate with certain perceptions, e.g., education level and political leanings were associated with the level of agreement to the statement "sharks are there for my enjoyment to catch" and "I want to catch the biggest shark possible", respectively. Operators follow best fishing practices to minimise stress to sharks and 100% of operators wanted to contribute to research. Currently 43% (n = 3) submit catch data and one operator tags sharks. This willingness to contribute to research could improve our understanding of blue shark population structure, habitat use, and post-release mortality rates associated with recreational angling. This will not only help sustain shark stocks but also engage anglers in understanding the threats to sharks and benefit recreational fisheries that rely on stable shark populations. • Historical fears of sharks do not exist amongst anglers. • Instead, a positive relationship between anglers and sharks exists around the UK. • Few fishing operators around the UK partake in shark research. • However, anglers are keen to do more for shark conservation. [ABSTRACT FROM AUTHOR]

Many shark and ray species (Class Chondrichthyes, herein 'sharks') are threatened by overfishing. Tackling this requires implementation of context-specific fisheries management measures, which are both technically effective and socio-economically feasible. Here we explore the cost-effectiveness of various input-oriented management measures for mitigating capture of seven priority shark taxa (i.e., threatened and CITES-listed species) in a small-scale longline mixed-species shark fishery in Indonesia, where there is a need to balance difficult trade-offs between conservation and socio-economic objectives. We apply Boosted Regression Trees (BRT) to analyse five years of landings and profit data, to identify and assess the relative influence of different plausible management measures (e.g., effort restrictions, gear restrictions, spatio-temporal closures). We then use predictive models to inform a semi-quantitative assessment of the hypothetical cost-effectiveness of these management measures, based on the estimated conservation benefits (reduced risk of capture of priority taxa) and socio-economic cost (relative profit foregone). Our results show that fishery closures in January–March, depth limits at <100 m, hook limits at <500 hooks, and gear restrictions on bottom longlines could have the greatest relative conservation impact for lowest profit foregone. However, there are clear trade-offs between taxa, with these measures primarily benefiting Critically Endangered bottlenose wedgefish (Rhynchobatus Australiae) and scalloped hammerheads (Sphyrna lewini), while potentially increasing pressure on Vulnerable silky sharks (Carcharhinus falciformis) and Endangered mako sharks (Isurus spp.). When shark fishing is important for economic welfare, and entire fishery closures or buy-outs are unfeasible, managing small-scale shark fisheries for multiple outcomes may require hard choices. This may require prioritising slow-growing Critically Endangered taxa for protection – by restricting fishing during seasons and at depths in which they are most susceptible to capture – while faster-growing taxa can continue to provide benefits for coastal communities. [ABSTRACT FROM AUTHOR]

Sharks and their cartilaginous relatives (Class Chondrichthyes, herein 'sharks') are one of the world's most threatened species groups. Their slow life history traits and vulnerability to capture make them particularly susceptible to overfishing, and they are widely caught in both target and by-catch fisheries. Fisheries management measures that can effectively reduce shark fishing mortality are urgently required to halt population declines and species extinctions. We provide an overview of typical measures for understanding and managing risks to sharks, and highlight critical gaps relating to incorporating socio-economic factors in to research and management. We argue that neglecting these factors hinders effective shark conservation, and has negative consequences for people. We emphasise the importance of a holistic approach, which explicitly considers socio-economic factors in decision-making. Based on this, we propose the first framework for assessing feasibility in a shark management context, which could be integrated with traditional fisheries risk assessments in order to bridge this gap. This framework considers key dimensions of the costs, benefits and overall enabling environment for shark management in a given fishery. Overall, managers and policy makers must consider socio-economic factors in shark conservation efforts to deliver better outcomes for sharks and people. Our simple feasibility framework can support this by enabling costs, benefits and context to be explicitly considered in planning and policy-making, alongside the typical biological and technical risks to sharks in fisheries. • An overview of typical measures for managing risks to sharks is given. • Gaps relating to socio-economic aspects of management are highlighted. • Socio-economic complexities of managing shark fisheries are described. • Priorities for including socio-economic factors in decision-making are discussed. • A framework to assess feasibility in shark management planning is proposed. [ABSTRACT FROM AUTHOR]