Microplastics in seafood: Consumer preferences and valuation for mitigation technologies.

Microplastics, an emerging pollutant, have garnered widespread attention due to potential repercussions on human health and the environment. Given the critical role of seafood in food security, growing concerns about microplastics might be detrimental to meeting future global food demand. This study employed a discrete choice experiment to investigate Chilean consumers' preferences for technology aimed at mitigating microplastic levels in mussels. Using a between-subjects design with information treatments, we examined the impact of informing consumers about potential human health and environmental effects linked to microplastics pollution on their valuation for the technology. We found that the information treatments increased consumers' willingness to pay for mussels. Specifically, consumers were willing to pay a premium of around US$ 4 for 250 g of mussel meat with a 90 % depuration efficiency certification. The provision of health impact information increased the price premium by 56 %, while the provision of environmental information increased it by 21 %. Furthermore, combined health and environmental information significantly increased the probability of non-purchasing behavior by 22.8 % and the risk perception of microplastics for human health by 5.8 %. These results emphasized the critical role of information in shaping consumer preferences and provided evidence for validating investment in research and development related to microplastic pollution mitigation measures.

Monitoring the fabric of nature: using allometric trophic network models and observations to assess policy effects on biodiversity.

Species diversity underpins all ecosystem services that support life. Despite this recognition and the great advances in detecting biodiversity, exactly how many and which species co-occur and interact, directly or indirectly in any ecosystem is unknown. Biodiversity accounts are incomplete; taxonomically, size, habitat, mobility or rarity biased. In the ocean, the provisioning of fish, invertebrates and algae is a fundamental ecosystem service. This extracted biomass depends on a myriad of microscopic and macroscopic organisms that make up the fabric of nature and which are affected by management actions. Monitoring them all and attributing changes to management policies is daunting. Here we propose that dynamic quantitative models of species interactions can be used to link management policy and compliance with complex ecological networks. This allows managers to qualitatively identify 'interaction-indicator' species, which are highly impacted by management policies through propagation of complex ecological interactions. We ground the approach in intertidal kelp harvesting in Chile and fishers' compliance with policies. Results allow us to identify sets of species that respond to management policy and/or compliance, but which are often not included in standardized monitoring. The proposed approach aids in the design of biodiversity programmes that attempt to connect management with biodiversity change. This article is part of the theme issue 'Detecting and attributing the causes of biodiversity change: needs, gaps and solutions'.

Four ways blue foods can help achieve food system ambitions across nations.

Blue foods, sourced in aquatic environments, are important for the economies, livelihoods, nutritional security and cultures of people in many nations. They are often nutrient rich1, generate lower emissions and impacts on land and water than many terrestrial meats2, and contribute to the health3, wellbeing and livelihoods of many rural communities4. The Blue Food Assessment recently evaluated nutritional, environmental, economic and justice dimensions of blue foods globally. Here we integrate these findings and translate them into four policy objectives to help realize the contributions that blue foods can make to national food systems around the world: ensuring supplies of critical nutrients, providing healthy alternatives to terrestrial meat, reducing dietary environmental footprints and safeguarding blue food contributions to nutrition, just economies and livelihoods under a changing climate. To account for how context-specific environmental, socio-economic and cultural aspects affect this contribution, we assess the relevance of each policy objective for individual countries, and examine associated co-benefits and trade-offs at national and international scales. We find that in many African and South American nations, facilitating consumption of culturally relevant blue food, especially among nutritionally vulnerable population segments, could address vitamin B12 and omega-3 deficiencies. Meanwhile, in many global North nations, cardiovascular disease rates and large greenhouse gas footprints from ruminant meat intake could be lowered through moderate consumption of seafood with low environmental impact. The analytical framework we provide also identifies countries with high future risk, for whom climate adaptation of blue food systems will be particularly important. Overall the framework helps decision makers to assess the blue food policy objectives most relevant to their geographies, and to compare and contrast the benefits and trade-offs associated with pursuing these objectives.

Untangling social-ecological interactions: A methods portfolio approach to tackling contemporary sustainability challenges in fisheries.

Meeting the objectives of sustainable fisheries management requires attention to the complex interactions between humans, institutions and ecosystems that give rise to fishery outcomes. Traditional approaches to studying fisheries often do not fully capture, nor focus on these complex interactions between people and ecosystems. Despite advances in the scope and scale of interactions encompassed by more holistic methods, for example ecosystem-based fisheries management approaches, no single method can adequately capture the complexity of human-nature interactions. Approaches that combine quantitative and qualitative analytical approaches are necessary to generate a deeper understanding of these interactions and illuminate pathways to address fisheries sustainability challenges. However, combining methods is inherently challenging and requires understanding multiple methods from different, often disciplinarily distinct origins, demanding reflexivity of the researchers involved. Social-ecological systems' research has a history of utilising combinations of methods across the social and ecological realms to account for spatial and temporal dynamics, uncertainty and feedbacks that are key components of fisheries. We describe several categories of analytical methods (statistical modelling, network analysis, dynamic modelling, qualitative analysis and controlled behavioural experiments) and highlight their applications in fisheries research, strengths and limitations, data needs and overall objectives. We then discuss important considerations of a methods portfolio development process, including reflexivity, epistemological and ontological concerns and illustrate these considerations via three case studies. We show that, by expanding their methods portfolios, researchers will be better equipped to study the complex interactions shaping fisheries and contribute to solutions for sustainable fisheries management.

A dynamic simulation model to support reduction in illegal trade within legal wildlife markets.

Sustainable wildlife trade is critical for biodiversity conservation, livelihoods, and food security. Regulatory frameworks are needed to secure these diverse benefits of sustainable wildlife trade. However, regulations limiting trade can backfire, sparking illegal trade if demand is not met by legal trade alone. Assessing how regulations affect wildlife market participants' incentives is key to controlling illegal trade. Although much research has assessed how incentives at both the harvester and consumer ends of markets are affected by regulations, little has been done to understand the incentives of traders (i.e., intermediaries). We built a dynamic simulation model to support reduction in illegal wildlife trade within legal markets by focusing on incentives traders face to trade legal or illegal products. We used an Approximate Bayesian Computation approach to infer illegal trading dynamics and parameters that might be unknown (e.g., price of illegal products). We showcased the utility of the approach with a small-scale fishery case study in Chile, where we disentangled within-year dynamics of legal and illegal trading and found that the majority (∼77%) of traded fish is illegal. We utilized the model to assess the effect of policy interventions to improve the fishery's sustainability and explore the trade-offs between ecological, economic, and social goals. Scenario simulations showed that even significant increases (over 200%) in parameters proxying for policy interventions enabled only moderate improvements in ecological and social sustainability of the fishery at substantial economic cost. These results expose how unbalanced trader incentives are toward trading illegal over legal products in this fishery. Our model provides a novel tool for promoting sustainable wildlife trade in data-limited settings, which explicitly considers traders as critical players in wildlife markets. Sustainable wildlife trade requires incentivizing legal over illegal wildlife trade and consideration of the social, ecological, and economic impacts of interventions.

Un Modelo Dinámico de Simulación para Asistir en la Reducción del Comercio Ilegal dentro de Mercados Legales de Vida Silvestre Resumen El comercio sustentable de vida silvestre es crítico para la conservación de la biodiversidad, los medios de subsistencia y la seguridad alimentaria. Son necesarios marcos regulatorios para asegurar estos diversos beneficios del comercio sustentable de vida silvestre. Sin embargo, las regulaciones que limitan el comercio pueden ser contraproducentes, generando un mercado ilegal si la demanda no se suple solamente con el comercio legal. El análisis de cómo las regulaciones afectan a los incentivos de los participantes del comercio de vida silvestre es de suma importancia para controlar el comercio ilegal. Mientras que muchas investigaciones se han centrado en analizar cómo las regulaciones afectan tanto a quienes consumen como quieren proveen visa silvestre, , poco se ha hecho para entender los incentivos de los intermediarios. Construimos un modelo dinámico de simulación para asistir en la reducción del comercio ilegal de vida silvestre dentro de los mercados legales, enfocándonos en los incentivos que enfrentan los intermediarios para comercializar productos legales o ilegales. Usamos un enfoque de Computación Bayesiana Aproximada para inferir las dinámicas del comercio ilegal y los parámetros que podrían ser desconocidos (p. ej.: el precio de los productos ilegales). Demostramos la utilidad del modelo mediante el caso de estudio de una pesquería de pequeña escala en Chile, en donde desentrañamos las dinámicas del comercio legal e ilegal y estimamos que la mayor parte del pescado comercializado es ilegal. Utilizamos el modelo para analizar el efecto de intervenciones para mejorar la sustentabilidad de la pesquería y para explorar los trade-offs entre metas ecológicas, económicas y sociales. Las simulaciones de escenarios mostraron que incluso incrementos significativos (más del 200%) de parámetros que recreaban intervenciones permitieron solamente mejoras moderadas en la sustentabilidad ecológica y social de la pesquería a un costo económico sustancial. Estos resultados exponen cuán desequilibrados están los incentivos de los intermediarios hacia el comercio de productos ilegales por encima de los legales en esta pesquería. Nuestro modelo proporciona una herramienta innovadora para la promoción del comercio sustentable de vida silvestre en entornos con datos limitados, y considera explícitamente a los intermediarios como actores críticos dentro del comercio de vida silvestre. El comercio sustentable de vida silvestre requiere incentivar el comercio legal sobre el ilegal y la consideración del impacto social, ecológico y económico de las intervenciones.

Rights and representation support justice across aquatic food systems.

Injustices are prevalent in food systems, where the accumulation of vast wealth is possible for a few, yet one in ten people remain hungry. Here, for 194 countries we combine aquatic food production, distribution and consumption data with corresponding national policy documents and, drawing on theories of social justice, explore whether barriers to participation explain unequal distributions of benefits. Using Bayesian models, we find economic and political barriers are associated with lower wealth-based benefits; countries produce and consume less when wealth, formal education and voice and accountability are lacking. In contrast, social barriers are associated with lower welfare-based benefits; aquatic foods are less affordable where gender inequality is greater. Our analyses of policy documents reveal a frequent failure to address political and gender-based barriers. However, policies linked to more just food system outcomes centre principles of human rights, specify inclusive decision-making processes and identify and challenge drivers of injustice.

An experimental look at trust, bargaining, and public goods in fishing communities.

Pro-social behavior is crucial to the sustainable governance of common-pool resources such as fisheries. Here, we investigate how key socioeconomic characteristics influence fishers' pro-social and bargaining behavior in three types of experimental economic games (public goods, trust, and trade) conducted in fishing associations in Chile. Our games revealed high levels of cooperation in the public goods game, a high degree of trust, and that sellers rather than buyers had more bargaining power, yet these results were strongly influenced by participants' socioeconomic characteristics. Specifically, gender, having a secondary income source, age, and being the main income provider for the household all had a relationship to multiple game outcomes. Our results highlight that engagement in pro-social behaviors such as trust and cooperation can be influenced by people's socioeconomic context.

Blue food demand across geographic and temporal scales.

Numerous studies have focused on the need to expand production of 'blue foods', defined as aquatic foods captured or cultivated in marine and freshwater systems, to meet rising population- and income-driven demand. Here we analyze the roles of economic, demographic, and geographic factors and preferences in shaping blue food demand, using secondary data from FAO and The World Bank, parameters from published models, and case studies at national to sub-national scales. Our results show a weak cross-sectional relationship between per capita income and consumption globally when using an aggregate fish metric. Disaggregation by fish species group reveals distinct geographic patterns; for example, high consumption of freshwater fish in China and pelagic fish in Ghana and Peru where these fish are widely available, affordable, and traditionally eaten. We project a near doubling of global fish demand by mid-century assuming continued growth in aquaculture production and constant real prices for fish. Our study concludes that nutritional and environmental consequences of rising demand will depend on substitution among fish groups and other animal source foods in national diets.

A framework for assessing and intervening in markets driving unsustainable wildlife use.

Understanding how markets drive unsustainable wildlife use is key for biodiversity conservation. Yet most approaches to date look at isolated components of wildlife markets, hindering our ability to intervene effectively to improve sustainability. To better assess and intervene in wildlife markets, we propose a framework that integrates three analytical levels. The first level, "actor", assesses the underlying motivations and mechanisms that allow or constrain how actors benefit from wildlife markets. The second level, "inter-actor", assesses the configuration of wildlife product supply-chains and the type of competition between actors participating in wildlife markets. The third level, "market", evaluates supply-demand dynamics, quantity and price determinants, and the presence and effect of illegal products flowing into markets. We showcase the utility of the framework in a data-limited small-scale fishery case study (common hake, Merluccius gayi gayi in Chile); our mixed-method analysis provided relevant, tailored management recommendations for improving sustainability. Tackling markets driving unsustainable wildlife use needs integrated approaches that bring together the diversity of factors affecting wildlife market dynamics.

Gaps, biases, and future directions in research on the impacts of anthropogenic land-use change on aquatic ecosystems: a topic-based bibliometric analysis.

Anthropogenic land use change (ALUC) satisfies human needs but also impacts aquatic ecosystems. Aquatic ecosystems are intrinsically linked with terrestrial landscapes, an association that is already recognized as a key factor to address future research and effective governance. However, the complexity and range of the impact of ALUC in aquatic ecosystems have been fundamental challenges and have implicitly routed the analysis to particular segments, drivers, management, or effects of the theme. In this study, we present an attempt to frame the subject in a broader context through a topic-based bibliometric analysis. Our aim is to identify possible biases and gaps in the current scientific literature and detect the main topics that have characterized the theme. Our results show an unequal distribution of articles by country when we analyzed the authors' affiliation and also a slight increase in contributions from social and economic disciplines, although they are still underrepresented. Moreover, we distinguish topics whose prevalence seems to change, especially those topics where the use of scenario analysis and multi-stressors are considered. We discuss the main biases and gaps revealed by our results, concluding that future studies on the impact of ALUC on aquatic ecosystems should better integrate social and economic disciplines and expand geographic frontiers.

Effects of experience with access regimes on stewardship behaviors of small-scale fishers.

Governance regimes that assign exclusive access to support collective action are increasingly promoted to manage common-pool resources under the premise that they foster environmental stewardship. However, experimental evidence linked to existing policies that support this premise is lacking. Overlapping access policies in small-scale fisheries provide a unique opportunity to test the effects of access regimes on users' stewardship behaviors. We performed a lab-in-the-field experiment to assess how fishers' previous experience with access regimes relates to compliance and peer enforcement (n = 120). Fishers' compliance and peer-enforcement decisions were compared in a common-pool-resource game. Treatments differed in framing to represent exclusive access and pseudo-open access regimes, both of which fishers face in real life. To contrast behavior in the game with real-life observations, we compared fishers' associations that have shown relatively high and low management performance under exclusive access policies. Compliance and peer enforcement were higher under the exclusive access treatment than under the pseudo-open access treatment only for fishers' associations with high management performance in real life. Behaviors in the game reflected differences between associations in real life. Our results support previous research on ocean governance by experimentally assessing the role of access regimes in determining users' stewardship and suggest potential mechanisms for stewardship internalization.

Efectos de la experiencia con regímenes de acceso sobre comportamientos de gestión responsable de pescadores a pequeña escala Resumen Las políticas que asignan acceso exclusivo a grupos de usuarios para apoyar la acción colectiva son cada vez más promovidas para el manejo de recursos de uso comunitario bajo la premisa de que fomentan la gestión ambiental responsable. Sin embargo, la evidencia experimental vinculada a políticas existentes que respalde esta premisa es insuficiente. La superposición de diversas políticas de acceso en las pesquerías a pequeña escala proporciona una oportunidad única para analizar los efectos de los regímenes de acceso sobre el comportamiento de gestión de los usuarios. Realizamos un experimento, llevando el laboratorio al campo, para evaluar cómo la experiencia previa de los pescadores con regímenes de acceso se relaciona con sus comporatamientos de cumplimiento y de sanción de pares (n = 120). Comparamos el cumplimiento con cutoas de extracción de los pescadores y sus decisiones de sancionar a pares que incumplian las cuotas en un juego de recursos de uso comunitario entre dos tratamientos. Los tratamientos variaban en la contextualización del juego para representar una pesquería de acceso exclusivo y una de pseudo libre acceso, a las que se enfrentan los pescadores en la vida real. Para contrastar el comportamiento en el juego con las observaciones de la vida real, comparamos los resultados de asociaciones de pescadores que han mostrado un desempeño de manejo relativamente alto y bajo con las políticas de acceso exclusivo. El cumplimiento y la sanción de pares fueron mayores bajo el tratamiento de acceso exclusivo que bajo el de pseudo libre acceso sólo para aquellas asociaciones de pescadores con un alto desempeño de manejo en la vida real. Los comportamientos en el juego reflejaron las diferencias entre las asociaciones en la vida real. Nuestros resultados respaldan investigaciones previas sobre la governanza de recursos marinos mediante la evaluación experimental del papel que tienen las políticas de acceso en la determinación de la gestión del usuario y sugieren mecanismos potenciales para la internalización de dicha gestión.

Harnessing the diversity of small-scale actors is key to the future of aquatic food systems.

Small-scale fisheries and aquaculture (SSFA) provide livelihoods for over 100 million people and sustenance for ~1 billion people, particularly in the Global South. Aquatic foods are distributed through diverse supply chains, with the potential to be highly adaptable to stresses and shocks, but face a growing range of threats and adaptive challenges. Contemporary governance assumes homogeneity in SSFA despite the diverse nature of this sector. Here we use SSFA actor profiles to capture the key dimensions and dynamism of SSFA diversity, reviewing contemporary threats and exploring opportunities for the SSFA sector. The heuristic framework can inform adaptive governance actions supporting the diversity and vital roles of SSFA in food systems, and in the health and livelihoods of nutritionally vulnerable people-supporting their viability through appropriate policies whilst fostering equitable and sustainable food systems.

Author Correction: A transition to sustainable ocean governance.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Sustainability transformations: socio-political shocks as opportunities for governance transitions.

Faced with accelerating environmental challenges, research on social-ecological systems is increasingly focused on the need for transformative change towards sustainable stewardship of natural resources. This paper analyses the potential of rapid, large-scale socio-political change as a window of opportunity for transformative change of natural resources governance. We hypothesize that shocks at higher levels of social organization may open up opportunities for transformation of social-ecological systems into new pathways of development. However, opportunities need to be carefully navigated otherwise transformations may stall or lead the social-ecological system in undesirable directions. We investigate (i) under which circumstances socio-political change has been used by actors as a window of opportunity for initiating transformation towards sustainable natural resource governance, (ii) how the different levels of the systems (landscape, regime and niche) interact to pave the way for initiating such transformations and (iii) which key features (cognitive, structural and agency-related) get mobilized for transformation. This is achieved through analyzing natural resource governance regimes of countries that have been subject to rapid, large-scale political change: water governance in South Africa and Uzbekistan and governance of coastal fisheries in Chile. In South Africa the political and economic change of the end of the apartheid regime resulted in a transformation of the water governance regime while in Uzbekistan after the breakdown of the Soviet Union change both at the economic and political scales and within the water governance regime remained superficial. In Chile the democratization process after the Pinochet era was used to transform the governance of coastal fisheries. The paper concludes with important insight on key capacities needed to navigate transformation towards biosphere stewardship. The study also contributes to a more nuanced view on the relationship between collapse and renewal.

The future of food from the sea.

Global food demand is rising, and serious questions remain about whether supply can increase sustainably1. Land-based expansion is possible but may exacerbate climate change and biodiversity loss, and compromise the delivery of other ecosystem services2-6. As food from the sea represents only 17% of the current production of edible meat, we ask how much food we can expect the ocean to sustainably produce by 2050. Here we examine the main food-producing sectors in the ocean-wild fisheries, finfish mariculture and bivalve mariculture-to estimate 'sustainable supply curves' that account for ecological, economic, regulatory and technological constraints. We overlay these supply curves with demand scenarios to estimate future seafood production. We find that under our estimated demand shifts and supply scenarios (which account for policy reform and technology improvements), edible food from the sea could increase by 21-44 million tonnes by 2050, a 36-74% increase compared to current yields. This represents 12-25% of the estimated increase in all meat needed to feed 9.8 billion people by 2050. Increases in all three sectors are likely, but are most pronounced for mariculture. Whether these production potentials are realized sustainably will depend on factors such as policy reforms, technological innovation and the extent of future shifts in demand.

A transition to sustainable ocean governance.

Human wellbeing relies on the Biosphere, including natural resources provided by ocean ecosystems. As multiple demands and stressors threaten the ocean, transformative change in ocean governance is required to maintain the contributions of the ocean to people. Here we illustrate how transition theory can be applied to ocean governance. We demonstrate how current economic and social systems can adapt to existing pressures and shift towards ocean stewardship through incorporation of niche innovations within and across economic sectors and stakeholder communities. These novel approaches support an emergent but purposeful transition and suggest a clear path to a thriving and vibrant relationship between humans and the ocean. Oceans provide important natural resources, but the management and governance of the ocean is complex and the ecosystem is suffering as a result. The authors discuss current barriers to sustainable ocean governance and suggest pathways forward.

Estimating illegal fishing from enforcement officers.

While illegal, unreported, and unregulated (IUU) fishing is a premier issue facing ocean sustainability, characterizing it is challenging due to its clandestine nature. Current approaches can be resource intensive and sometimes controversial. Using Chile as an example, we present a structured process leveraging existing capacity, fisheries officers, that provides a monitoring tool to produce transparent and stand-alone estimates on the level, structure, and characteristics of illegal fishing. We provide a national illegal fishing baseline for Chile, estimating illegal activity for 20 fisheries, representing ~ 70% of annual national landings. For four fisheries, we also estimate the relative importance of illegal activities across sectors, stakeholders, and infrastructure. While providing new information, our results also confirm previous evidence on the general patterns of illegality. Our approach provides an opportunity for government agencies to formalize their institutional knowledge, while accounting for potential biases and reducing fragmentation of knowledge that can prevent effective enforcement. Estimating illegal activity directly from fisheries enforcement officers is complementary to existing approaches, providing a cost-effective, rapid, and rigorous method to measure, monitor, and inform solutions to reduce IUU fishing.