Trends in phytoplankton communities within large marine ecosystems diverge from the global ocean

Large marine ecosystems (LMEs) are highly productive regions of the world ocean under anthropogenic pressures; we analyzed trends in sea surface temperature (SST), cloud fraction (CF), and chlorophyll concentration (CHL) over the period 1998–2019. Trends in these parameters within LMEs diverged from the world ocean. SST and CF inside LMEs increased at greater rates inside LMEs, whereas CHL decreased at a greater rates. CHL declined in 86% of all LMEs and of those trends, 70% were statistically significant. Complementary analyses suggest phytoplankton functional types within LMEs have also diverged from those characteristic of the world ocean, most notably, the contribution of diatoms and dinoflagellates, which have declined within LMEs. LMEs appear to be warming rapidly and receiving less solar radiation than the world ocean, which may be contributing to changes at the base of the food chain. Despite increased fishing effort, fishery yields in LMEs have not increased, pointing to limitations related to productivity. These changes raise concerns over the stability of these ecosystems and their continued ability to support services to human populations.

Climate mitigation averts corrosive acidification in the upper ocean

The invasion of anthropogenic carbon into the global ocean poses an existential threat to calcifying marine organisms1–4. Observations indicate that conditions corrosive to aragonite shells, unprecedented in the surface ocean, are already occurring in mesoscale upwelling features of the North Pacific2,5,6 and Southern Ocean7, and modeling experiments indicate that large volumes of the global ocean8 including the polar ocean’s surface might become corrosive to aragonite by 20304,9–13. Such changes are expected to compress important marine habitats, but the pathways by which habitat compression manifests over global scales, and their sensitivity to mitigation, remain unexplored. Using a suite of large ensemble projections from an Earth system model14,15, we assess the effectiveness of climate mitigation for averting habitat loss at the ecologically-critical horizon of the base of the ocean’s euphotic zone. We find that without mitigation, 40-42% of this sensitive horizon experiences conditions corrosive to aragonite by 2100, with moderate mitigation this reduces to 16-19%, and with aggressive mitigation to 6-7%. Mitigation has a stronger effect on the eastern relative to western domains of the northern extratropical ocean with some of the greatest benefits in the ocean’s most productive Large Marine Ecosystems, including the California Current and Gulf of Alaska. This work reveals the significant impact that mitigation efforts compatible with the Paris Agreement target of 1.5°C could have upon preserving marine habitats that are vulnerable to ocean acidification.

Are marine biodiversity hotspots still blackspots for barcoding?

Marine biodiversity underpins ecosystem health and societal well-being. Preservation of biodiversity hotspots is a global challenge. Molecular tools, like DNA barcoding and metabarcoding, hold great potential for biodiversity monitoring, possibly outperforming more traditional taxonomic methods. However, metabarcoding-based biodiversity assessments are limited by the availability of sequences in barcoding reference databases; a lack thereof results in high percentages of unassigned sequences. In this study we (i) present the current status of known vs. barcoded marine species at a global scale based on online taxonomic and genetic databases; and (ii) compare the current status with data from ten years ago. Then we analyzed occurrence data of marine animal species from five Large Marine Ecosystems (LMEs) classified as biodiversity hotspots, to identify any consistent disparities in COI barcoding coverage between geographic regions and at phylum level. Barcoding coverage varied among LMEs (from 36.8% to 62.4% COI-barcoded species) and phyla (from 4.8% to 74.7% COI-barcoded species), with Porifera, Bryozoa and Platyhelminthes being highly underrepresented, compared to Chordata, Arthropoda and Mollusca. We demonstrate that although barcoded marine species increased from 9.5% to 14.2% since the last assessment in 2011, about 15,000 (corresponding to 7.8% increase) new species were described from 2011 to 2021. The next ten years will thus be crucial to enroll concrete collaborative measures and long term initiatives (e.g., Horizon 2030, Ocean Decade) to populate barcoding libraries for the marine realm.

Primary production ultimately limits fisheries economic performance

Living marine resources (LMRs) contribute considerably to marine economies. Oceans continue to respond to the effects of global change, with environmental factors anticipated to impact future seafood production and its associated economic performance. Here we document novel relationships between primary productivity and LMR-based economics for US regional marine ecosystems and 64 international large marine ecosystems (LMEs). Intermediate relationships between production, total biomass, fisheries landings, revenue, and LMR-based employment are also elucidated. We found that all these factors were dependent on the amount of basal production in a given system. In addition, factors including human population, exploitation history, and governance interventions significantly influenced these relationships. As system productivity plays a foundational role in determining fisheries-based economics throughout global LMEs, greater accounting for these relationships has significant implications for global seafood sustainability and food security. Quantifying the direct link between primary production and fisheries economic performance serves to better inform ecosystem overfishing thresholds and their economic consequences. Further recognition and understanding of these relationships is key to ensuring that these connections are accounted for more effectively in sustainable management practices.

Smart Fishery: A Systematic Review and Research Agenda for Sustainable Fisheries in the Age of AI

Applications of artificial intelligence (AI) technologies for improving the sustainability of the smart fishery have become widespread. While sustainability is often claimed to be the desired outcome of AI applications, there is as yet little evidence on how AI contributes to the sustainable fishery. The purpose of this paper is to perform a systematic review of the literature on the smart fishery and to identify upcoming themes for future research on the sustainable fishery in the Age of AI. The findings of the review reveal that scholarly attention in AI-inspired fishery literature focuses mostly on automation of fishery resources monitoring, mainly detection, identification, and classification. Some papers list marine health and primary production which are vital dimensions for Large Marine Ecosystems to recycle nutrients to sustain anticipated production levels. Very few reviewed articles refer to assessing individual needs, particularly fishers, from AI deployment in fisheries and policy response from governments. We call for future AI for sustainable fishery studies on how fishers perceive AI needs, and how governments possess a tangible strategy or depth of understanding on the regulation of AI concerning smart fishery systems and research on resilience-enhancing policies to promote the value and potentials of the AI-inspired smart fishery in different locations.

Navigating the Complexity of Regional Ocean Governance Through the Large Marine Ecosystems Approach

Governance is a multifaceted and complex process, involving a wide range of stakeholders from numerous institutions and individuals with different interests, agendas and sets of skills. A number of barriers exist for states to work together on securing their shared coastal and marine ecosystems, with discussions often becoming clouded when disputes arise over Exclusive Economic Zones, borders, oil and gas resources, continental shelves, maritime transport, and fisheries. Over the last twenty-six years, the Global Environment Facility’s (GEF) International Waters focal area has utilized the Large Marine Ecosystem (LME) approach to navigate the complex problems related to transboundary issues affecting the world’s marine ecosystems, of which forty-one out of sixty-six are shared (62%) by one or more countries. To overcome the disputes and assumptions about the intentions of neighboring states, the GEF developed the Transboundary Diagnostic Analysis-Strategic Action Programme (TDA-SAP) assessment and strategic planning processes to help countries learn how to work together and build trust. This formal and inclusive process analyses all pertinent factual and scientific information to set priorities for action. This practical method for integrating science into management has provided an effective approach to inform and advance sustainable LME management and governance regimes; however, there is not a one size fits all approach. This review presents six examples from the GEF International Waters portfolio that demonstrate how the LME Approach and TDA-SAP process have helped countries find the best way to mainstream ecosystem-based management approaches into existing contexts and politics. While these examples span a wide range of different settings (geographic, political, socio-economic, temporal), they have all applied the LME Approach and TDA-SAP process to tackle complex regional ocean governance issues. Each example provides a historical perspective, the key results achieved, and their unique lessons learned/best practices. Furthermore, the review identifies some of the overall shortcomings of the process and the common lessons learned, underscoring the complex and daunting challenge of achieving effective governance for multi-country LMEs. The experience provided by these examples shows that practical ecosystem-based management of the ocean and its coasts not only requires flexibility and adaptability, but also time, associated long-term vision and commitment.