This contribution will examine the question of the complex – and on some degree paradoxical – correlation between sustainability goals and perspectives of deep seabed mining. On the one hand, it may be argued that deep seabed mining is a positive step towards sustainability since the metals and mineral resources that can be extracted from the Area are needed for the green transition. On the other hand, the fact that there is currently insufficient scientific knowledge about the Area’s ecosystem and the potential environmental impact of deep seabed mining activities to it seems to oppose sustainability goals and deep seabed mining. This contribution will address the issue from a purely legal perspective. Is there any inherent contradiction between sustainability and deed seabed mining from a public international law, environmental law and law of the sea perspective? Can there be a harmonious articulation between them? The currently negotiated “Mining Code” (Draft exploitation regulations) will be analysed in order to examine if it aims for a conciliation between sustainability and deep seabed mining activities. Claims about “precautionary pause” or “moratorium” will also be studied in this light. 

How to cite: Aloupi, N.: Deep Seabed Mining and Sustainability: a legal perspective, One Ocean Science Congress 2025, Nice, France, 3–6 Jun 2025, OOS2025-119, https://doi.org/10.5194/oos2025-119, 2025.

Currently, approximately 2.7 million km² of the deep seafloor are being explored for metal ores, with potentially a few hundred thousand km² that could be mined within the next 20-30 years. At the mined location, the removal of ores will result in the loss of ore-dependent microbes and fauna, such as sponges and corals, and of the ecosystem functions they provide. The loss can last up to millions of years, the length of time that it takes for the ores to form. It is probable that species extinction will occur. The mining plumes will extend beyond the mined seafloor area and reach into the water column, with the geographic scale dependent on the technology used and the location. The noise generated by mining may spread over hundreds of kilometers in the water. There is currently limited knowledge available regarding the impact of mining plumes or noise on deep-sea life, such as mortality, chronic toxic effects, change in behavior or reproduction that may impact subsequent generations.

Scientific knowledge is currently insufficient for effective environmental management of deep-sea mining. Recent scientific findings, such as significant organic carbon production at inactive vents, the discovery of animal life in the earth’s crust below vents, or 5000 new discovered animal species at polymetallic nodule fields, highlight the unknows in deep sea and the importance of implementing the precautionary principle. Major questions that need to be answered to allow for effective management include for example: What species are present? What ecosystem functions are present? Is restoration possible? How much impact can occur before biodiversity is lost and ecosystem functions are disrupted? Importantly, strategic as well as region specific environmental goals and objectives need to be discussed and set. Otherwise, effective protection of the marine environment from harmful effects that may arise from deep-seabed-related activities may not be ensured.

How to cite: Gollner, S.: Environmental impacts of deep-sea mining and implications for management, One Ocean Science Congress 2025, Nice, France, 3–6 Jun 2025, OOS2025-638, https://doi.org/10.5194/oos2025-638, 2025.

Autochthonous uses of the ocean are often considered only from a distant and patrimonial perspective, as a legacy from the past that has largely disappeared (such as the knowledge of navigating by the positions of the stars in the South Pacific). Such an exoticizing view of indigenous relations with the ocean tends to erase the contemporary political issues that indigenous peoples face in relation to the deep sea: issues of sovereignty, control, legitimacy of indigenous knowledge and uses of the ocean in decision-making processes – but also socio-economic issues related to the transformations of uses of maritime spaces and circulations within them in a globalized world. Indigenous voices on these issues are heterogeneous and come from contrasting places, and should therefore not be lumped together under the single label of "guardians of the Ocean". Likewise, indigenous knowledge does not stand in opposition to scientific knowledge, and indigenous uses of the ocean do not stand outside of global, capitalist economic uses of the deep sea (whether these uses are real or virtual). The aim of this paper is therefore to present a contemporary picture of autochthonous issues related to the uses of the deep sea in the South Pacific, restoring the heterogeneity of autochthonous positions and the complex science-policy-society entanglements they encounter.

How to cite: Muni Toke, V.: Autochthonous Knowledge and Uses of the Deep Sea: Contemporary  Issues from a South Pacific Perspective, One Ocean Science Congress 2025, Nice, France, 3–6 Jun 2025, OOS2025-361, https://doi.org/10.5194/oos2025-361, 2025.

Our deep ocean remains the last great unexplored wilderness of our planet, both in terms of biodiversity and potential marine genetic resources. It is the largest ecosystem on earth, but the least known, with recent estimates from Pacific regions showing 90% of deep-sea species as undescribed. The extreme conditions and habitat variety of the deep ocean drive adaptation and evolutionary novelty; extremophile organisms that live in deep-sea vents or abyssal plains therefore present vast potential for marine genetic resources of benefit to society. However, our oceans are under an existential threat from unprecedented biodiversity loss, impacted by climate change, pollution, and human activities such as fisheries, shipping and extractive industries. We are facing a future of countless deep-sea species and potentially invaluable marine natural products being lost before they are even discovered. Addressing ocean health is key for conservation of marine biodiversity and genetic resources, of benefit to all. Deep sea marine genetic resources and natural products could help address pressing needs, including climate change mitigation, human health- including needs for new medicines and addressing a looming antimicrobial resistance crisis, and for environmentally sound industrial processes. Discoveries can inspire new technologies, and the deep ocean provides the best biodiscovery platform on our planet. Here, scientific innovation under robust ocean governance is needed. It is time to operationalise the new Biodiversity Beyond National Jurisdiction (BBNJ) Agreement with sustainable, equitable and interdisciplinary research that addresses both knowledge gaps for biodiversity of our deep ocean habitats but also their potential societal value in terms of natural products and wider benefits.

How to cite: Rabone, M.: Deep discovery: the potential of marine genetic resources from deep sea habitats and paths forward for addressing key societal challenges under the BBNJ Agreement, One Ocean Science Congress 2025, Nice, France, 3–6 Jun 2025, OOS2025-1471, https://doi.org/10.5194/oos2025-1471, 2025.

Seamounts are prominent underwater mountains rising from the seafloor in ocean basins worldwide. These structures are often recognised in the deep-sea as benthic biodiversity hotspots, offering diverse habitats across depth gradients that support a wide variety of marine species. Seamounts are ecologically significant, and since 2006 the United Nations General Assembly (UNGA) has called for their protection as Vulnerable Marine Ecosystems (VMEs), together with cold-water coral gardens and hydrothermal vents. Despite this, seamounts face escalating threats from human activities, such as destructive fishing practices, the effects of climate change, and the potential impacts of deep-sea mining. These pressures underscore the need for enhanced conservation and management strategies.

The Deep-Ocean Stewardship Initiative (DOSI) is a global network of thousands of experts from over 115 countries, which integrates science, technology, policy, law and economics to advise on ecosystem-based management of resource use in the deep ocean. In October 2024, the DOSI Fisheries Working Group with support from the UN Ocean Decade program Challenger 150, hosted the Seamount Science Summit workshop at the University of Hawai‘i, the first major gathering focused on seamount ecology and conservation in over a decade.

The summit convened 26 global seamount experts to assess current ecological knowledge, review management practices, and develop strategies to improve resilience in seamount ecosystems amid ongoing anthropogenic pressures. Through presentations, plenary sessions and subgroup discussions, the expert group identified several frameworks to improve management of seamount ecosystems. Here, we present key outputs from the workshop including recommendations for Regional Fisheries Management Organizations (RFMOs) to manage seamounts as VMEs in order to prevent Significant Adverse Impacts (SAIs). We present frameworks to enhance data collection on seamounts fostering industry contributions towards scientific processes within RFMOs and enabling data-informed management of seamount ecosystems. Additionally, the expert group emphasises integrating cumulative impacts, including historical fishing pressures and current and projected climate change effects, to reduce bottom fishing impacts and enhance seamount ecosystem resilience. We also present science priorities and discuss pathways to overcome knowledge gaps in seamount research.

How to cite: Victorero, L., Vinha, B., Girard, F., Du Preez, C., Baco-Taylor, A., Beide, V., Gianni, M., Howell, K., Clark, M., Judah, A. B., Watling, L., Butfield, B., and Kobayashi, D.: Towards Global Ecosystem-Based Management for Benthic Seamount Ecosystems, One Ocean Science Congress 2025, Nice, France, 3–6 Jun 2025, OOS2025-1218, https://doi.org/10.5194/oos2025-1218, 2025.