Marcos Llope

The current delineation of the southern Canary Current Large Marine Ecosystem fisheries management zones responds only to political divisions rather than ecological features or a combination of both. In this paper, we implemented three time series analysis techniques on spatially explicit daily and monthly resolved data sets from satellite and reanalysis. Methods are based on climatologies, wavelet analysis and clusters and seasonal regression models, thus covering different aspects of the upwelling dynamics. Due to the overall convergence of the outputs of the analysis, by describing the spatiotemporal dynamics of oceanographic processes and biogeochemical features, we delineate distinct robust subregions and examine their recent trends. Our results identified four subregions: (a) a tropical subregion (12–18–21°N), (b) a Western Sahara (18–21°N to 25°N), (c) a South Morocco (26–28°N) and (d) a North Morocco subregion (29–35°N). The tropical subregion continues to exhibit a highly seasonal upwelling pattern with decreasing duration of winter upwelling events, in contrast with the other subregions that show slight variations in their seasonality. Although wind‐driven upwelling has intensified in Western Sahara, leading to a cooling trend in sea surface temperature, chlorophyll‐a does not show a concomitant increase. The North Morocco subregion is experiencing an increase in both the intensity and duration of the upwelling, making it more closely resemble the permanent upwelling zone of Western Sahara. This revisited subdivision provides a robust framework for ecosystem‐based management by incorporating current ecological variability. Monitoring of hydrographic and biological trends is essential to adapt boundaries to future conditions.

In the Canary Current Large Marine Ecosystem (CCLME), significant variations in upwelling dynamics have been observed in the last decades, but their impact on small pelagic fish biomass remains unclear. Identifying the factors driving these stock variations is challenging, particularly for heavily overexploited species. In this study, we attempt to disentangle the influence of fishing and environmental factors on the biomass of Sardinella aurita and Sardina pilchardus using structural causal models. Fisheries data alone cannot explain the year-to-year variations in biomass, indicating that other factors are at play. Furthermore, unrealistic results using fishing data point to high levels of illegal, unreported, and unregulated catches, leading to an underestimation of S. aurita biomass. In the tropical subregion (southernmost CCLME), fluctuations in the biomass of S. aurita are primarily driven by upwelling dynamics rather than temperature or salinity. A similar pattern is observed in the Western Sahara subregion, where primary productivity, along with the previous year’s biomass of S. aurita, is the main driver of biomass fluctuations. Additionally, a negative relationship between S. aurita biomass in the two subregions suggests that the Western Sahara may serve as a refuge during periods of declining suitable habitat in the tropical subregion. In the Western Sahara subregion, fluctuations in S. pilchardus biomass are influenced by primary productivity, while in the South Morocco subregion the driving factor is likely temperature. The results highlight the significant influence of environmental variables on pelagic fish biomass, underscoring the potential impacts of climate change on the distribution and abundance of these species. Such shifts could profoundly affect local economies and food security, while also heightening geopolitical tensions among nations competing for shared marine resources. Comprehensive evaluation and effective management strategies that account for environmental changes are urgently required.

Marine ecosystems are facing multiple pressures from human activities, such as fishing and nutrient inputs from farming and agriculture, compounded by the global effects of climate change. As a result, the ecosystem services that societies depend on are at risk from the cumulative impact of these pressures. To better understand how different ecosystems respond, it is essential to assess their resilience. While predicting ecosystem resilience remains challenging, significant progress has been made in developing methods to measure it. In this study, we assessed resilience in four northern European marine ecosystems: the Icelandic Waters, the Barents Sea, the Baltic Sea, and the North Sea, spanning 3 to 5 decades. “Folded stability landscapes” were constructed for the Baltic and North Sea. This region provides a unique setting, with a south-north gradient from temperate to subarctic environments and a southeast-northwest gradient from open to semienclosed topographies. The Icelandic Waters and Barents Sea evolved relatively continuously, while the Baltic Sea and North Sea underwent more drastic changes. By comparing results across these gradients, we explore the role of isolation, level of pressures, and food web complexity in shaping resilience patterns and discuss the implications for managing resilient marine ecosystems in the future.

One of West Africa’s defining characteristics is its strong reliance on the sea. This is especially true for the Lower Senegal River Basin, on the border between Mauritania and Senegal, where a perfect storm is unfolding, with ripple effects reaching Europe. Overfishing and collateral damage to marine biodiversity undermine the future of fishing. Coastal erosion, worsened by sea-level rise, swallow homes, while saltwater intrusion has made farming increasingly difficult. Offshore oil and gas development, seen by many as the final straw, claimed an ancestral fishing ground. The site now hosts a liquefied natural gas hub designed to meet Europe’s demand following the ban on Russian gas. Young people see no future at home and brave the open ocean to the Canary Islands, fuelling political tension in Spain and across the EU. Despite obvious links between ecology, livelihoods, and migration, policy responses remain fragmented. The EU funds border control operations like FRONTEX while neglecting the root causes. Fisheries agreements focus narrowly on stock levels, ignoring broader ecological and social impacts while energy projects rely on simplistic environmental assessments based on IUCN red-list species and protected areas. This article combines personal frontline stories with an analysis to show how current marine policies miss the bigger socio-ecological picture. We recommend that the European Commission upgrade its next generation of Sustainable Fisheries Partnership Agreements and ambitions for (alternative) energy sources into integrated policy strategies that are socially just and address concerns for biodiversity more effectively.

The diversity-stability relationship persists as a central ecological debate, as existing work primarily examines direct diversity and structural drivers, while empirical evidence clarifying how direct and structure-mediated pathways jointly shape ecosystem multistability remains limited. Here, we analyzed 217 global marine food webs, quantifying structural properties and multidimensional stability to evaluate how diversity and structure jointly influence stability. Our analyses reveal that diversity is consistently linked to stability through dual pathways: positively associated with resistance and resilience via indirect structural mediation, yet negatively correlated with local stability unless interaction strength is accounted for. Critically, omitting structural mediation yields a net negative diversity-stability correlation, whereas integrating food web structure uncovers context-dependent positive relationships, underscoring structural metrics as pivotal explanatory variables. Our findings reconcile the diversity-stability debate by showing that the food web structure mediates context-dependent stability outcomes—integrating direct and indirect pathways resolves contradictions and advances actionable metrics for conservation strategies resilient to environmental changes.

Marine biota are redistributing at a rapid pace in response to climate change and shifting seascapes. While changes in fish populations and community structure threaten the sustainability of fisheries, our capacity to adapt by tracking and projecting marine species remains a challenge due to data discontinuities in biological observations, lack of data availability, and mismatch between data and real species distributions. To assess the extent of this challenge, we review the global status and accessibility of ongoing scientific bottom trawl surveys. In total, we gathered metadata for 283,925 samples from 95 surveys conducted regularly from 2001 to 2019. We identified that 59% of the metadata collected are not publicly available, highlighting that the availability of data is the most important challenge to assess species redistributions under global climate change. Given that the primary purpose of surveys is to provide independent data to inform stock assessment of commercially important populations, we further highlight that single surveys do not cover the full range of the main commercial demersal fish species. An average of 18 surveys is needed to cover at least 50% of species ranges, demonstrating the importance of combining multiple surveys to evaluate species range shifts. We assess the potential for combining surveys to track transboundary species redistributions and show that differences in sampling schemes and inconsistency in sampling can be overcome with spatio‐temporal modeling to follow species density redistributions. In light of our global assessment, we establish a framework for improving the management and conservation of transboundary and migrating marine demersal species. We provide directions to improve data availability and encourage countries to share survey data, to assess species vulnerabilities, and to support management adaptation in a time of climate‐driven ocean changes.

Marine biota is redistributing at a rapid pace in response to climate change and shifting seascapes. While changes in fish populations and community structure threaten the sustainability of fisheries, our capacity to adapt by tracking and projecting marine species remains a challenge due to data discontinuities in biological observations, lack of data availability, and mismatch between data and real species distributions. To assess the extent of this challenge, we review the global status and accessibility of ongoing scientific bottom trawl surveys. In total, we gathered metadata for 283,925 samples from 95 surveys conducted regularly from 2001 to 2019. 59% of the metadata collected are not publicly available, highlighting that the availability of data is the most important challenge to assess species redistributions under global climate change. We further found that single surveys do not cover the full range of the main commercial demersal fish species and that an average of 18 surveys is needed to cover at least 50% of species ranges, demonstrating the importance of combining multiple surveys to evaluate species range shifts. We assess the potential for combining surveys to track transboundary species redistributions and show that differences in sampling schemes and inconsistency in sampling can be overcome with vector autoregressive spatio-temporal modeling to follow species density redistributions. In light of our global assessment, we establish a framework for improving the management and conservation of transboundary and migrating marine demersal species. We provide directions to improve data availability and encourage countries to share survey data, to assess species vulnerabilities, and to support management adaptation in a time of climate-driven ocean changes.