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Managing natural resources under large-scale environmental fluctuations like the El Niño Southern Oscillation (ENSO) is likely to become increasingly important under climate change. Forecasts of environmental conditions are improving, but the best response to an unfavorable forecast remains unclear; many practitioners advocate reducing harvest as a more precautionary approach, while prior economic theory favors increasing harvest. Using logistic and age-structured fisheries models, we show that informational constraints — uncertain stock estimates and restrictions on harvest policies — play a central role in choosing how to respond to a forecasted shock. With perfect knowledge and no policy constraints, risk-neutral managers should increase harvest when a negative shock is forecast. However, informational constraints may drive the optimal response to a forecast of a negative shock toward or away from precaution. Precautionary forecast responses arise when informational constraints make the harvest policy insufficiently sensitive to the true resource status. In contrast, uncertainty about the stock size can lead to more aggressive forecast responses when stock dynamics are nonlinear and not all fish are susceptible to fishing.

Evidence of large‐scale biodiversity degradation in marine ecosystems has been reported worldwide, yet most research has focused on few species of interest or on limited spatiotemporal scales. Here we assessed the spatial and temporal changes in the taxonomic and functional composition of fish communities in European seas over the last 25 years (1994–2019). We then explored how these community changes were linked to environmental gradients and fishing pressure. We show that the spatial variation in fish species composition is more than two times higher than the temporal variation, with a marked spatial continuum in taxonomic composition and a more homogenous pattern in functional composition. The regions warming the fastest are experiencing an increasing dominance and total abundance of r‐strategy fish species (lower age of maturity). Conversely, regions warming more slowly show an increasing dominance and total abundance of K‐strategy species (high trophic level and late reproduction). Among the considered environmental variables, sea surface temperature, surface salinity and chlorophyll‐a most consistently influenced communities' spatial patterns, while bottom temperature and oxygen had the most consistent influence on temporal patterns. Changes in communities' functional composition were more closely related to environmental conditions than taxonomic changes. Our study demonstrates the importance of integrating community‐level species traits across multi‐decadal scales and across a large region to better capture and understand ecosystem‐wide responses and provides a different lens on community dynamics that could be used to support sustainable fisheries management. [ABSTRACT FROM AUTHOR]

Management of crustacean fisheries is often data‐limited, and techniques used in finfish fisheries are often inappropriate for crustaceans due to life‐history differences. Limitations in modeling capacity and data availability make it difficult to determine the status of crustacean stocks using model‐based biological reference points (BRPs), but BRPs are a key component of successful fisheries management. Using crustacean fishery case studies depicting model‐based and empirical management strategies, we synthesized the current state of crustacean fisheries management with respect to data availability and use of management controls. Input and output controls can be successful with supplemental BRPs, but whatever methods are used must explicitly consider species' unique life‐history characteristics. In data‐limited fisheries, output controls can effectively conserve a species under high levels of exploitation. Implementation of discrete BRPs can improve sustainability of both emerging and data‐rich crustacean fisheries, to make these quantitative metrics a valuable tool for crustacean management globally. [ABSTRACT FROM AUTHOR]

The world's oceans supply food and livelihood to billions of people, yet species' shifting geographic ranges and changes in productivity arising from climate change are expected to profoundly affect these benefits. We ask how improvements in fishery management can offset the negative consequences of climate change; we find that the answer hinges on the current status of stocks. The poor current status of many stocks combined with potentially maladaptive responses to range shifts could reduce future global fisheries yields and profits even more severely than previous estimates have suggested. However, reforming fisheries in ways that jointly fix current inefficiencies, adapt to fisheries productivity changes, and proactively create effective transboundary institutions could lead to a future with higher profits and yields compared to what is produced today.

International and regional policies aimed at managing ocean ecosystem health need quantitative and comprehensive indices to synthesize information from a variety of sources, consistently measure progress, and communicate with key constituencies and the public. Here we present the second annual global assessment of the Ocean Health Index, reporting current scores and annual changes since 2012, recalculated using updated methods and data based on the best available science, for 221 coastal countries and territories. The Index measures performance of ten societal goals for healthy oceans on a quantitative scale of increasing health from 0 to 100, and combines these scores into a single Index score, for each country and globally. The global Index score improved one point (from 67 to 68), while many country-level Index and goal scores had larger changes. Per-country Index scores ranged from 41-95 and, on average, improved by 0.06 points (range -8 to +12). Globally, average scores increased for individual goals by as much as 6.5 points (coastal economies) and decreased by as much as 1.2 points (natural products). Annual updates of the Index, even when not all input data have been updated, provide valuable information to scientists, policy makers, and resource managers because patterns and trends can emerge from the data that have been updated. Changes of even a few points indicate potential successes (when scores increase) that merit recognition, or concerns (when scores decrease) that may require mitigative action, with changes of more than 10-20 points representing large shifts that deserve greater attention. Goal scores showed remarkably little covariance across regions, indicating low redundancy in the Index, such that each goal delivers information about a different facet of ocean health. Together these scores provide a snapshot of global ocean health and suggest where countries have made progress and where a need for further improvement exists.

Climate change is a new disrupter to global fisheries systems and their governance frameworks. It poses a pressing management challenge, particularly in China, which is renowned as the world's largest fishing country and seafood producer. As climate change continues to intensify in the region and climate awareness grows within the country's national policy, the need to understand China's fisheries' resilience to the escalating climate crisis becomes paramount. In this study, we conduct an interdisciplinary analysis to assess the vulnerability and risk of China's marine capture fisheries in response to climate change. This study employs a spatially explicit, indicator-based approach with a coupled social-ecological framework, focusing on 67 species and 11 coastal regions. By integrating diverse sets of climatic, ecological, economic, societal, and governance indicators and information, we elucidate the factors that could hinder climate adaptation, including a limited understanding of fish early life stages, uncertainty in seafood production, unequal allocation and accessibility of resources, and inadequate consideration of inclusive governance and adaptive management. Our results show that species, which have managed to survive the stress of overfishing, demonstrate a remarkable ability to adapt to climate change. However, collapsing stocks such as large yellow croaker face a high risk due to the synergistic effects of inherent biological traits and external management interventions. We emphasize the imperative to build institutional, scientific, and social capacity to support fisheries adaptation. The scientific insights provided by this study can inform fisheries management decisions and promote the operationalization of climate-resilient fisheries in China and other regions. [ABSTRACT FROM AUTHOR]

Knowledge co-production offers a promising approach to design effective and equitable pathways to reach development goals. Fisheries Strategies for Changing Oceans and Resilient Ecosystems by 2030 (FishSCORE), a United Nations Ocean Decade programme, will co-produce knowledge that advances solutions for climate resilient fisheries through networks and partnerships that include scientists, stakeholders, practitioners, managers, and policy experts. FishSCORE will establish (1) a global network that will develop broadly relevant information and tools to assess and operationalize climate resilience in marine fisheries and (2) local and regional partnerships that will apply those tools to identify and forward context-specific resilience strategies. FishSCORE’s activities will be guided by a set of core principles that include commitments to inclusivity, equity, co-leadership, co-ownership, and reciprocity. FishSCORE will focus on identifying solutions for climate resilient fisheries, and it will also advance goals associated with capacity, power, and agency that will support iterative, pluralistic approaches to decision-making in fisheries experiencing ongoing climate-driven changes. This process of co-producing knowledge and strategies requires considerable investments of time from all partners, which is well aligned with the Ocean Decade. However, secure funding must be prioritized to support and implement co-production activities over this long time horizon. [ABSTRACT FROM AUTHOR]

Research shows that population status can be predicted using catch data, but there is little justification for why these predictions work or how they account for changes in fisheries management. We demonstrate that biomass can be reconstructed from catch data whenever fishing mortality follows predictable dynamics over time (called 'effort dynamics'), and we develop a state-space catch only model (SSCOM) for this purpose. We use theoretical arguments and simulation modeling to demonstrate that SSCOM can, in some cases, estimate population status from catch data. Next, we use meta-analysis to estimate effort dynamics for US West Coast groundfishes before and after fisheries management changes in the mid-1990s. We apply the SSCOM using meta-analytic results to data for eight assessed species and compare results with stock assessment and data-poor methods. Results indicate general agreement among all three methods. We conclude that effort dynamics provides a theoretical basis for using catch data to reconstruct biomass and has potential for conducting data-poor assessments. However, we still recommend that index and compositional data be collected to allow application of data-rich methods. Si la recherche a demontre que l'etat des populations peut etre predit a l'aide de donnees sur les prises, les travaux justifiant la pertinence de ces predictions et leur adequation pour expliquer les changements dans la gestion des peches demeurent tres limites. Nous demontrons que la biomasse peut etre reconstituee a partir de donnees sur les prises quand la mortalite par peche suit une dynamique previsible dans le temps (appelee la'dynamique de l'effort') et, a cette fin, developpons un modele d'espace d'etats reposant uniquement sur les prises (SSCOM). Nous faisons appel a des arguments theoriques et la simulation pour demontrer que le SSCOM peut, dans certains cas, estimer l'etat de la population a partir de donnees sur les prises. Nous utilisons ensuite la metaanalyse pour estimer la dynamique de l'effort pour les poissons de fond de la cote Ouest americaine avant et apres des changements a la gestion des peches au milieu des annees 1990. Nous appliquons le SSCOM en utilisant les resultats de la metaanalyse a des donnees pour huit especes evaluees et comparons les resultats a des methodes d'evaluation des stocks et reposant sur des donnees limitees. Les resultats indiquent une bonne concordance, en general, des trois methodes. Nous en concluons que la dynamique de l'effort constitue une base theorique pour l'utilisation de donnees sur les prises dans le but de reconstituer la biomasse et pourrait etre utile pour des evaluations basees sur des donnees limitees. Nous recommandons toutefois que des donnees indicielles et compositionnelles soient recueillies pour permettre l'application de methodes axees sur des donnees abondantes. [Traduit par la Redaction], Introduction Marine fisheries globally have an enormous value in terms of food production, employment, and income for small- and large-scale fishers (Ye et al. 2012). However, the vast majority of [...]

Marine reserves have not been widely used to conserve mobile species because species abundance levels can be highly variable over space and time. Here we explore the potential for marine reserves to reduce bycatch of mobile species using red snapper (Lutjanus campechanus) as a case study. Bycatch in Gulf of Mexico shrimp trawls is a major source of juvenile red snapper mortality, and marine reserves may be mandated if bycatch reduction targets are not met. Using geographic information system (GIS) analyses of fishery-independent data, we investigated whether red snapper juveniles concentrate in 'hot spots' and examined the trade-offs between abundance within hot spots (intensity) and predictability over time (persistence). These trade-offs allow fishery managers to tailor marine reserves to meet specific conservation goals. For red snapper, hot spots were primarily located around the 30 m isobath, with hot spots spread along the Texas coast in fall and clustered around the Texas-Louisiana border in summer. Increased intensity of hot spots led to lower persistence due to the smaller spatial area of higher intensity hot spots. Hot spots moved annually but generally persisted in the same locations over time, indicating that marine reserves could reduce red snapper bycatch. This approach provides a foundation for making informed decisions about design and placement of reserves for mobile species. Resume: Les reserves marines n'ont pas beaucoup servi a la conservation des especes mobiles parce que les niveaux d'abondance des especes peuvent varier considerablement dans le temps et l'espace. Nous examinons ici le potentiel des reserves marines dans la reduction des prises accessoires des especes mobiles en utilisant le vivaneau campeche (Lutjanus campechanus) comme modele. Les prises accessoires dans les chaluts a crevettes dans le golfe du Mexique representent une cause importante de mortalite juvenile de vivaneaux campeches et des reserves marines seront peutetre prescrites siles cibles de reduction des prises accessoires ne sont pas atteintes. Au moyen d'analyses de donnees independantes de la peche a l'aide du systeme d'information geographique (GIS), nous avons cherche a savoir siles jeunes vivaneaux campeches se concentrent en [much less than] points chauds ≫ et examine les compromis entre l'abondance dans les points chauds (intensite) et la previsibilite dans le temps (persistance). Ces compromis permettent aux gestionnaires de la peche d'ajuster les reserves marines afin d'atteindre des objectifs specifiques de conservation. Chez le vivaneau campeche, les points chauds se situent principalement aux environs de l'isobathe de 30 m; ils se repartissent le long de la cote du Texas en automne et se concentrent autour de la frontiere Texas-Louisiane en ete. L'intensite accrue dans les points chauds entraine une persistance reduite a cause de la surface spatiale restreinte des points chauds a forte intensite. Les points chauds peuvent se deplacer d'une annee a l'autre, mais ils persistent generalement aux memes endroits dans le temps, ce qui fait que des reserves marines pourraient reduire les captures accessoires de vivaneaux campeches. Notre methodologie fournit une base pour prendre des decisions eclairees sur la conception et la localisation de reserves pour les especes mobiles. [Traduit par la Redaction], Introduction Marine reserves are closures of areas to fishing, diving, or other activities that impact marine resources. Marine reserves are beneficial in preserving biodiversity, protecting habitat, reducing overfishing, and increasing [...]

Fisheries are critically important for nutrition, food security, livelihoods, and culture of hundreds of millions of people globally. As climate impacts on ocean ecosystems increase, policy-makers are asking critical questions about how to implement reforms at local and national levels to reach goals around improving performance of management systems, sustainability, equity, and resilience to climate change. These goals can be achieved by enhancing the structure, function, and biodiversity of marine ecosystems as climate change proceeds, together with adaptive, sustainable management. However, resource, technical, and governance capacities vary widely across management systems. These capacities will determine, in part, the best policy approaches to build resilience and overcome systemic challenges to equity and sustainability to stressors such as climate change. To illuminate how fisheries resilience can be improved within the constraints imposed by these capacity limits, we present case studies from Myanmar, Belize, Peru, and Iceland, which offer a spectrum of capacity conditions to explore social–ecological resilience challenges and solutions. Using a set of nine social–ecological resilience criteria, we examine each system's attributes that may confer or undermine resilience and explore interactions between them. We use this assessment to identify policy approaches that can help build resilience in each particular context. [ABSTRACT FROM AUTHOR]