Conserving genetic diversity is crucial for maintaining species’ evolutionary potential and resilience to environmental change. Yet, directly measuring genetic diversity across large spatial scales remains resource-intensive and impractical for conservation planning. Identifying reliable, accessible, and cost-effective spatial predictors of genetic diversity would significantly enhance our ability to incorporate genetic diversity into conservation efforts. Caribbean coral reefs represent a compelling system for investigating such predictors, as these ecosystems face unprecedented threats from disease outbreaks and climate change. Here, we investigate the utility of several environmental proxies as surrogates for genetic diversity, which may be useful for conservation planning in resource- or data-poor regions. To achieve this goal, we used reduced-representation genomic sequencing to estimate intraspecific genetic diversity, and in doing so, identified two genetically distinct and sympatric cryptic coral species in the Agaricia tenuifolia species complex. We employed a causal inference approach to assess the relationships between genetic alpha diversity and habitat area and connectivity, habitat heterogeneity, and temperature. Statistical investigations revealed that increased habitat heterogeneity, derived from remotely sensed habitat maps, was associated with lower genetic diversity within coral populations, suggesting that habitat characteristics promoting species diversity may not maintain high genetic diversity within a single species. Habitat area and connectivity, and temperature have predominantly negative effects on genetic diversity with coral habitat area and connectivity showing markedly contrasting responses in two cryptic taxa. Thus, our findings reveal that context matters greatly, as results differ between cryptic species, across variables, and among spatial scales.

The threat of Illegal, Unreported and Unregulated (IUU) fishing to global fisheries, particularly in lower‐income tropical regions, underscores the urgent need for science‐based solutions. This study explores the drivers and potential solutions to IUU fishing by Honduran fishers in the Cayman Crown reef, located within the territorial waters of Guatemala and Belize. We integrate science‐based and practical, local knowledge through household surveys and stakeholders' workshops, engaging fishers, government agencies and non‐governmental organizations NGOs to assess motivations for IUU fishing and possible interventions. Survey results reveal distinct spatial patterns in IUU fishing, with fishers from Omoa and Puerto Cortés being more likely to engage in IUU activities compared to those from Tela. Moreover, 16% of surveyed households reported involvement in Cayman Crown harvesting at some point, confirming previous findings on cross‐border IUU fishing in the region. The primary drivers of IUU fishing include the overexploitation of local fish stocks, declining landings (−44%), and economic hardship exacerbated by the COVID‐19 pandemic and extreme weather events. In response, stakeholders identified five key themes for potential solutions: governance, capacity building, livelihood diversification, environmental awareness, and bilateral cooperation. Governance, capacity building, and diversification emerged as the most promising solutions, with fishers expressing a strong desire for greater participation in management, training opportunities, and alternative income sources. Synthesis and applications: In summary, our study underscores the vital need for a collaborative, cross‐border and inclusive strategy that accounts for the heterogeneous drivers and solutions of IUU fishing across municipalities and stakeholder groups. Strengthening co‐management mechanisms, enhancing capacity building and implementing context‐appropriate livelihood diversification initiatives could improve fisheries governance and reduce illegal fishing incentives. Additionally, regional cooperation between Honduras, Guatemala, and Belize is essential to harmonize regulations and enforcement. This study provides a replicable framework for assessing IUU fishing in data‐poor contexts and underscores the importance of participatory approaches in fisheries governance to ensure long‐term sustainability and the well‐being of coastal communities. Read the free Plain Language Summary for this article on the Journal blog.

Aquaculture interventions and policies are now fundamental in sustainability agendas, particularly in supporting small-scale fisheries and coastal communities. These policies often rely on the "blue transitions" theory of change, which posits that an expansion of aquaculture will aid in recovering declining fish stocks and enhancing livelihoods. However, the blue transitions theory is relatively new, leaving many aspects uncertain, especially regarding how transition stages unfold and impact communities as they are expected to transform livelihoods. Frequently, these policies adopt a top-down approach driven by political and corporate interests at global or national levels, emphasizing environmental and economic benefits while neglecting local social, cultural, and historical contexts. This study aims to identify gaps in current blue transition policies at the local level through two empirical case studies in Baja California Sur, Mexico. Additionally, it evaluates the suitability of existing frameworks for incorporating justice in food system transitions for seafood system transitions and provides insights for developing more equitable blue food policies. Using an exploratory mixed methods approach from 2021 to 2023, including ethnography, interviews, surveys, and focus groups, this research delves into the complexities of aquaculture policies for communities going through blue transitions. Findings indicate that these policies often prioritize economic development over social, cultural, and historical considerations, leading to injustices within communities. The case studies reveal impacts and challenges such as intra-community conflict, illegal fishing, and threats to food security and resilience, as well as benefits like momentary economic gains. Applying a framework for just food system transitions, we advocate for flexible, community-centric policies that recognize local heterogeneity and empower communities to shape their transitions, including deciding whether a transition is appropriate. This study underscores the limitations of viewing aquaculture as a panacea for smallscale fisheries' challenges, emphasizing the need for holistic, multiscale management approaches. Contextualizing blue transitions within local realities and prioritizing food justice can promote just and equitable outcomes that address the nuanced needs of diverse coastal communities amidst global pressures.

Ensuring the sustainability of European stalked barnacle fisheries requires effective management strategies. Insights into the experience of resource users with different management strategies can help to assess their success. To explore the opinion of the harvesters on the management of local fisheries, we conducted a multi-regional survey in Spain, Portugal and France with varying degrees of co-management. We analysed their responses using a multinomial logistic regression to understand what drove the observed differences. No single optimal strategy to achieve sustainability emerged, and the analysis revealed that geographic region was the most significant variable explaining the preferences of harvester. In less developed co-management systems they favored general input and output restrictions and expressed a desire for greater involvement in co-management processes. Conversely, in highly developed co-management systems with Territorial User Rights for Fishers (TURFs) they preferred the most restrictive and spatially explicit management strategies, such as implementing harvest bans and establishing marine reserves. These preferences indicate that harvesters in TURF-based systems exhibit a high level of stewardship and commitment to sustainable resource management. Moreover, our results indicate that the majority of harvesters in the regions in Portugal and France, areas with less developed co-management, are willing to make changes to current management strategies, reflecting their awareness of the need for improvement. To enhance the development of sustainable management practices across the distributional range of fishery resources, management strategies do not only need to be tailored to each region's particular practices, needs, and characteristics, but also consider the readiness of resource users for specific strategies.

Aquaculture is the fastest-growing seafood production system globally, offering economic and social opportunities for small-scale fishing communities. Yet, it is often introduced through top-down, technocratic approaches that ignore the social-ecological realities of these communities. Drawing on four case studies from Mexico and Honduras, this study uses a multistage, participatory mixed-methods approach to examine the integration of aquaculture into existing fisheries. We focus on governance, social organization, economic assets, and cultural traditions, key yet understudied dimensions of implementation. Findings reveal that projects overlooking these interactions risk deepening inequities, displacing traditional livelihoods, and weakening community cohesion. Success depends on early economic support, recognition of local traditions and social structures, and the creation of context-specific governance systems. Centering community needs and experiences can help design equitable, place-based aquaculture initiatives that strengthen, rather than disrupt, small-scale fishing livelihoods.

This study explored the transformative journey of community-based natural resource management (CBNRM) in the Bay Islands National Marine Park, Honduras, revealing the interplay of cooperation, funding, and communication in fostering successful conservation initiatives. Using a mixed-method approach, we investigated the historical and legislative process and enabling conditions that led to the transition to CBNRM, based on Gruber's 12 key principles. In regards to the present CBNRM system, we looked at its strengths, its challenges, and whether its functioning is seen as satisfying by local resource-users. Findings showed that key CBNRM principles-including an enabling environment, conflict resolution, research-based decision-making, public trust, and monitoring-fostered the transition. Furthermore, satisfaction with reef management and perceived patrol effectiveness, which are pivotal aspects in CBNRM, exceeded 70% in Roatan. Challenges such as strengthening local institutions and enhancing compliance were identified. Nonetheless, co-managers are actively working to resolve these challenges by focusing on enforcement, diverse funding acquisition mechanisms and community participation. The study underscores the pivotal role of local NGOs and collaborative committees in facilitating successful CBNRM. By providing evidence-based insights, we highlight the efficacy of multilevel, co-management models in resource management and emphasize the value of adaptable strategies. These findings contribute to a deeper understanding of CBNRM dynamics in Latin America and the Caribbean, which may ultimately foster successful conservation initiatives in the Global South.

Genetic structure and connectivity information can be used to identify biological corridors and prioritize the conservation of areas that help maintain ecosystem integrity. Some marine fish, especially those of commercial interest, have been proposed as suitable indicators to identify potential marine biological corridors due to their high mobility among habitats and socioeconomic importance. In this study, we assessed the genetic structure of lane snapper populations in the Honduran Caribbean to evaluate connectivity and identify potential environmental barriers. Furthermore, we evaluated the genetic characteristics of the lane snapper on a larger spatial scale, including populations across the rest of its distribution range in the western Atlantic, using mtDNA and nuDNA markers. Our results demonstrate a significant genetic diversity of lane snappers in the Honduran Caribbean. Furthermore, despite their high dispersal potential, we observed genetic structuring in lane snapper populations on a larger spatial scale, resulting in the formation of two distinct groups throughout their distribution range: group 1 from Florida, the Gulf of Mexico, Honduras, and Colombia and group 2 from Puerto Rico and Brazil. This genetic differentiation can be attributed to oceanographic barriers such as river plumes and marine currents. These findings have the potential to significantly impact marine conservation and management efforts in the region, both at local and regional scales. It is anticipated that they will not only inform but also elicit a response, driving further action towards effective conservation measures. At a local scale, we recommend that conservation efforts focus on protecting critical habitats. At a regional scale, lane snappers should be included in the management plans of existing marine protected areas necessary to ensure the long-term sustainability of the species and the marine ecosystems in which it resides.

A two-year experiment investigated the effects of Pollicipes pollicipes (Gmelin, 1791) harvest on intertidal community structure and ecological diversity, as well as the recovery potential of P. pollicipes aggregations. The experiment was conducted at three locations along the West Asturian coast (Northern Spain) from July 2017 to July 2019. More intense exploitation resulted in reduced P. pollicipes and Mytilus spp. coverage, while Chthamalus spp. and Corallina spp. increased during the two years. Initially, the extraction of P. pollicipes lowered the ecological diversity of space occupying species, but this increased over time due to succession. While the recovery of exploited P. pollicipes aggregations was highly variable and slow, their coverage increased by up to 80% under caged non-extracted conditions in two years, leading to decreased diversity of primary space occupiers. Based on our findings, we suggest implementing two-yearly harvest bans to promote sustainability of this fishery.

Coral reefs are vulnerable to natural and anthropogenic impacts, especially tourism activities such as SCUBA diving and snorkeling. This study aims to assess diver carrying capacity and the impacts caused by SCUBA divers related to certification level and lionfish spear, through an underwater monitoring of 180 divers in Roatan, Honduras. Results reveal substantial variation in carrying capacity among dive sites, with a notable disparity of over 13,000 divers/year between sites with the lowest and highest capacities. Divers' behavior has significant implications for reef physical integrity. This study highlights the need to reassess the effectiveness of lionfish spearfishing as a control for invasive species and emphasizes the importance of comprehensive workshops and courses to enhance divers' awareness of potential ecological impacts. These findings contribute to understanding the ecological implications of recreational diving, calling for sustainable management practices and targeted educational efforts. Furthermore, the study underscores the significance of estimating and managing carrying capacity for long-term marine ecosystem sustainability. Incorporating SCUBA diving carrying capacity as a crucial tool for adaptative management enables monitoring and regulation of diver numbers in relation to reef status and tourism pressure.

Tropical coastal ecosystems are in decline worldwide due to an increasing suite of human activities, which threaten the biodiversity and human wellbeing that these ecosystems support. One of the major drivers of decline is poor water quality from land-based activities. This review summarises the evidence of impacts to coastal ecosystems, particularly coral reefs, from sediments, nutrients, chemicals and pathogens entering

Scleractinian corals, considered key reef ecosystem engineers, have suffered irreparable damage over the last decades, with causes widely attributed directly and indirectly to increased human pressure on coral communities. Stony coral tissue loss disease (SCTLD), first detected in Florida in 2014, by early 2023 had spread to 26 jurisdictions in the wider Caribbean, causing severe effects on coral reefs. In January 2020, monitoring efforts to detect SCTLD began on the island of Roatan in Honduras. The disease was first reported in Flowers Bay, Roatan, in September 2020. Since then, dedicated collaborative efforts have been made to assess the severity of the disease, mitigate its effects, and raise coral reef conservation awareness. To track the progression of the outbreak, presence-absence data were collected using the rover diver methodology. With at least 28 species affected, SCTLD has spread across the Bay Islands over a period of 13 months. Roatan and Utila have been the most impacted islands, with the disease encircling them rapidly at a rate of approximately 155 m/day. The spread of SCTLD was overall rapid, but geographical patterns were detected in Roatan, where it showed faster progression on the windward side than on the leeward side. Further research is required to explore whether these disparities are related to marine traffic, water quality, currents, or a combination of multiple factors. Our findings shed new knowledge on the spread of SCTLD in Honduras, which can provide insights for other Caribbean nations whose economies are also dependent on the health of their coral reefs.

Integrated management of coral reef foods, as a highly diverse set of blue foods, can contribute to addressing the dual challenges of malnutrition and biodiversity loss. Advances in nutrition research have made it possible to understand nutritional benefits on a species by species basis, and to make comparisons with benefits derived from land-based foods. We provide a series of considerations about current understanding of nutrition from coral reef foods, including the predominance of finfish in nutritional assessments, the importance of contaminants for food safety, uncertainty stemming from climate and cumulative impacts, and the need for locally specific assessments of food systems. Next we outline how nutrition, coral reef small-scale fisheries, and communities intersect. Aspects of equity and food sovereignty are reviewed as a basis for contextualizing current scientific understanding of nutrition while acknowledging who is actually benefiting nutritionally and materially from coral reef fisheries. Given this understanding of the state of knowledge of nutrition from coral reef foods, we encourage the development of nutrition-sensitive coral reef governance. We conclude with a set of recommendations for governance institutions, fishing organizations, philanthropic foundations, funding agencies, conservation organizations, and researchers, among others. To ensure coherence, we encourage these stakeholders to work with each other and with communities for implementation of the following recommendations: prioritize coral reef foods for local nutrition; advance gender equity and social inclusion; adopt a systems approach for coral reef foods; integrate food system policies with fisheries, public health, and development; strengthen small-scale fisheries rights, access, and governance; and assess and monitor coral reef foods systems.

Artisanal fisher associations have experienced a shift towards gender inclusivity over the past decade. We used the social-ecological systems framework developed by Elinor Ostrom to explore relationships between gender and collective action. Questionnaires were used to determine (1) motivations to join an association, (2) socio- demographic information, (3) perceptions on key collective action dimensions around leadership and norms within the association, and (4) perceived social performance. Surveys targeted artisanal fisher associations in Chile with varying gender compositions: exclusively male members, exclusively female members, mixed-gender led by a man, and mixed- gender led by a woman. Our results show that women and men have distinct motivations to join an association. Women are primarily motivated by a sense of belonging, while men are mainly motivated by the possibility of an increase in income. Furthermore, associations comprised of women displayed higher valuations on leadership, entrepreneurship, and participation in activities. This likely led to the significantly higher performance of associations that incorporated women (either women-only or mixed gender) in efficiency (30.1%– 40.3% higher) and cooperation (13.8%–30.8% higher). Our results extend the social-ecological systems framework towards understanding the role of gender in collective action for fisheries management and specifically contribute to build knowledge and implement novel policy which considers gender in artisanal fisheries in Chile.

In January 2020, a stakeholder workshop was organized as a knowledge sharing strategy among European stalked barnacle fisheries. Management of this fishery differs greatly among regions and ranges from less organized and governed at large scales (>100 km, coasts of SW Portugal and Brittany in France) to highly participatory systems which are co-managed at small spatial scales (10's km and less, Galicia and Asturias). Discussions revealed that poaching is ubiquitous, hard to eradicate, and adapts to all types of management. The stakeholders identified some key management initiatives in the fight against poaching: granting professional harvesters with exclusive access to the resource, increasing social capital among harvesters through tenure systems (e.g. Territorial Use Rights in Fisheries) that empower them as stewards of their resource and intensification of surveillance with the active participation of the harvesters. Furthermore, increased cooperation between fishers associations and regional fisheries authorities, improved legal frameworks, adoption of new technologies and the implementation of market-based solutions can also help coping with this systemic problem.

The health and integrity of coral reef ecosystems are in decline worldwide due to an increasing suite of human activities, which threaten biodiversity and human wellbeing. One of the major drivers of coral reef ecosystem decline is poor water quality from human activities on land. Land-based pollutants from human activities travel downstream via watersheds through groundwater flow and land areas drained by streams – and are funnelled into coastal environments. There is now ample evidence of the linkages between human activities in watersheds and elevated levels of pollutants in water discharged to coastal marine ecosystems. There is also a growing understanding of the myriad and often interacting impacts these pollutants have on coral reef ecosystems and the critical services they provide for associated dependent communities. This white paper reviews the linkages between landbased runoff and coral reef ecosystems, with four specific objectives to: (1) review how sediments, nutrients, chemicals, and pathogens affect corals and reef-associated organisms at a variety of life stages; (2) assess how these processes impact associated dependent human populations; (3) identify existing knowledge needs; and (4) provide science-based management options.

Numerical biophysical models are a standard methodology used to provide estimates of larval dispersal and population connectivity for marine species with a bi-phasic life cycle. However, confidence on biophysical models, tested by confronting model estimates with empirical evidence, is seldomly assessed. We compared time-series estimates of larval supply of the stalked barnaclePollicipes pollicipesto rocky shores in 3 regions around the Iberian Peninsula (Asturias, Galicia, SW Portugal) with recruitment observations made at monthly intervals for 2 yr. Supply estimates were made with the Regional Ocean Modelling system using several larval behaviour scenarios, while the number of recruits on the stalks of adult barnacles was used as a measure of recruitment intensity. Cross-correlation analysis showed that passive, surface-dwelling and ontogenetically migrating larval scenarios generally produced significant positive correlations at time lags of 0 to +2 mo at the regional level but not at sub-regional or site levels. None of the scenarios produced a substantially better fit than the others, and all 3 produced estimates of average realized dispersal (-73 to +63 km in the S/W and N/E directions) and larval retention (2.0 to 2.4%) that were numerically very similar. These estimates indicate high levels of connectivity, either during larval life or via steppingstone processes, within and between the 3 regions. Based on these estimates, we advocate that the management of theP. pollicipesfishery requires an interactive, polycentric governance system at transregional, regional and local scales, which will give the resource a higher possibility of persistence by diversifying the fishery’s management portfolio.