Trend analysis: Marine & freshwater biodiversity

Why It Matters

Aquatic ecosystems generate services worth an estimated US$28 trillion per year, yet freshwater vertebrate populations have declined by 83 percent since 1970 and roughly one-third of assessed marine fish stocks remain overfished (WWF, 2024; FAO, 2024). Despite covering 71 percent of the planet's surface and holding 80 percent of its biodiversity by species count, oceans and freshwater systems receive only 1 percent of global conservation finance (Deutz et al., 2024). Three trends are converging to shift this imbalance. Environmental DNA (eDNA) monitoring is making aquatic biodiversity measurement faster, cheaper and more comprehensive than ever before. The Agreement under UNCLOS on Biodiversity Beyond National Jurisdiction (BBNJ Treaty) is extending governance to the high seas for the first time. And corporate water stewardship programmes are scaling from pilot initiatives into basin-wide commitments backed by measurable ecological targets. Together, these forces are creating new obligations, new markets and new tools for sustainability professionals working across fisheries, shipping, agriculture, beverages and financial services.

Key Concepts

Environmental DNA (eDNA). Organisms shed DNA into their environment through skin cells, mucus, excretions and decomposition. By filtering water samples and sequencing the genetic material, scientists can detect the presence and relative abundance of hundreds of species without physically observing or capturing them.

BBNJ Treaty. Formally the Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas Beyond National Jurisdiction, the BBNJ Treaty was adopted in June 2023 after nearly two decades of negotiation. It establishes mechanisms for area-based management tools (including marine protected areas on the high seas), environmental impact assessments, benefit-sharing from marine genetic resources and capacity building.

Water stewardship. The Alliance for Water Stewardship (AWS) standard defines a framework through which water users engage with other stakeholders in a catchment to achieve shared water-related outcomes. Corporate water stewardship goes beyond facility-level efficiency to address basin-wide ecological health, social equity and governance.

Marine protected areas (MPAs). Zones where human activities are restricted to conserve marine ecosystems. The Global Biodiversity Framework Target 3 calls for 30 percent of oceans to be effectively conserved by 2030; as of 2025, approximately 8.3 percent of oceans fall within designated MPAs, though only 2.8 percent are fully or highly protected (UNEP-WCMC, 2025).

Freshwater biodiversity hotspots. Freshwater ecosystems occupy less than 1 percent of the Earth's surface but support approximately 10 percent of all known species. Lakes, rivers, wetlands and groundwater systems face compounding pressures from abstraction, pollution, damming and climate change.

Trend 1: eDNA Monitoring Adoption

The eDNA market for biodiversity assessment is growing at a 22 percent compound annual growth rate and is projected to reach US$850 million by 2028 (Grand View Research, 2025). Adoption is being driven by falling sequencing costs, regulatory mandates and the technology's suitability for aquatic environments where traditional surveys are expensive and disruptive.

In the regulatory domain, the UK Environment Agency began requiring eDNA surveys for great crested newt detection in planning applications in 2024, establishing a precedent that is expanding to fish and invertebrate assessments (UK Environment Agency, 2024). The European Commission's Water Framework Directive revision, expected in 2026, is considering eDNA-based biomonitoring as a complement to existing ecological status indicators.

NatureMetrics, which has processed over 50,000 eDNA samples globally by 2025, offers a subscription platform that enables repeat monitoring of rivers, lakes and marine sites at roughly 60 percent lower cost per species detected compared with electrofishing or seine-net surveys (NatureMetrics, 2025). In Norway, the Institute of Marine Research deployed eDNA metabarcoding across 120 fjord stations in 2024, detecting 347 fish species in a single sampling campaign that would have required years of conventional trawl surveys (Thomsen & Willerslev, 2025).

Corporate users are adopting eDNA for supply-chain due diligence. Nestlé Waters partnered with NatureMetrics in 2024 to monitor aquatic biodiversity around 12 bottling sites in France, Switzerland and Canada, integrating the data into TNFD-aligned disclosures (Nestlé, 2025). Anglo American deployed eDNA monitoring across five mine-adjacent watersheds in South Africa and Brazil, using quarterly sampling to detect early indicators of pollution impact on macroinvertebrate communities (Anglo American, 2025).

The technology does face limitations. eDNA degrades within hours to days in warm or UV-exposed water, which can produce false negatives. Detection rates vary by species biomass and shedding behaviour. Standardisation of sampling protocols, reference databases and bioinformatic pipelines remains a work in progress, though ISO technical committee TC 147 is developing international standards for eDNA-based water quality assessment expected by late 2026 (ISO, 2025).

Trend 2: BBNJ Treaty and High-Seas Governance Expansion

The BBNJ Treaty represents the most significant expansion of ocean governance since UNCLOS entered into force in 1994. As of February 2026, 112 countries have signed the agreement and 27 have ratified it, with the treaty expected to enter into force by late 2026 once 60 ratifications are achieved (IISD, 2026).

The treaty creates four pillars: marine genetic resources and benefit-sharing, area-based management tools including high-seas MPAs, environmental impact assessments (EIAs) for activities beyond national jurisdiction, and capacity building with technology transfer. For companies operating in deep-sea mining, high-seas fishing, submarine cable laying and shipping, the EIA provisions introduce new compliance requirements.

The High Seas Alliance (2025) estimates that establishing MPAs covering 30 percent of the high seas, aligned with GBF Target 3, would protect roughly 120 million square kilometres of ocean. Currently, fewer than 1 percent of areas beyond national jurisdiction have any form of conservation designation. Proposed priority sites include the Sargasso Sea, the Costa Rica Thermal Dome, the Lord Howe Rise and the mid-Atlantic Ridge hydrothermal vent fields.

Early implementation signals are emerging. The International Seabed Authority (ISA) postponed deep-sea mining exploitation regulations in 2025, citing the need to reconcile its mandate with BBNJ obligations (ISA, 2025). Norway, which approved seabed mineral exploration in its continental shelf in January 2024, faced legal challenges referencing BBNJ environmental assessment standards (IISD, 2026). The shipping industry is preparing for potential speed restrictions and route modifications around designated high-seas MPAs: Maersk's 2025 sustainability report committed to aligning fleet routing with future high-seas conservation zones (Maersk, 2025).

For sustainability professionals, the BBNJ Treaty introduces a framework that will shape EIA requirements, supply-chain traceability obligations for marine genetic resources, and stakeholder engagement expectations for any company with high-seas operational footprints.

Trend 3: Corporate Water Stewardship Programmes

Corporate water stewardship has matured from facility-level metering into basin-scale ecological restoration commitments. The Alliance for Water Stewardship reported 380 certified sites globally by the end of 2025, up from 210 in 2023, covering approximately 1.5 billion cubic metres of freshwater basin commitments (AWS, 2025).

Leading programmes demonstrate the shift. AB InBev, through its 100+ Accelerator, invested US$20 million between 2023 and 2025 in watershed restoration projects across high-stress basins in Mexico, India and South Africa, targeting measurable improvements in base flow, sediment load and riparian biodiversity (AB InBev, 2025). Microsoft's water-positive commitment, announced in 2020, moved into implementation phase in 2024 with replenishment projects in the Colorado River basin, the Jordan River watershed and Chennai's Chembarambakkam Lake, cumulatively restoring access to over 4.5 million cubic metres of water by 2025 (Microsoft, 2025).

The beverage sector is particularly active. Diageo achieved AWS certification across 12 distillery and brewery sites spanning Scotland, Kenya, India and Australia by mid-2025. Its Johnnie Walker Striding Man Foundation invested GBP 8 million in peatland restoration across Scottish catchments, generating co-benefits for water quality, carbon sequestration and freshwater species habitat (Diageo, 2025).

Financial pressure is reinforcing these programmes. CDP's 2025 water security questionnaire found that companies disclosing basin-level water risks experienced, on average, a 12 percent reduction in water-related cost of capital compared with non-disclosing peers in the same sector (CDP, 2025). The Science Based Targets Network (SBTN) published its freshwater targets methodology in 2024, requiring companies to set context-based targets that account for local hydrological conditions rather than relying on uniform percentage reductions (SBTN, 2024).

Integration with biodiversity outcomes is the next frontier. Projects that restore wetlands, reconnect floodplains or remove barriers to fish migration generate measurable freshwater biodiversity gains alongside water quantity and quality improvements. The Nature Conservancy's Freshwater Programme has mapped 6,000 priority dam removal and fish passage sites across North America and Europe, creating a pipeline of investable water stewardship projects with quantifiable species recovery metrics (TNC, 2025).

Market Dynamics

The marine and freshwater biodiversity market is fragmented across monitoring technology, conservation finance and corporate compliance segments. eDNA monitoring platforms are consolidating: NatureMetrics raised a US$25 million Series B in 2024, while Swiss startup Aqua-T acquired two European eDNA laboratories in 2025 (NatureMetrics, 2025; Aqua-T, 2025). Demand-side growth is tied to regulatory triggers: the UK BNG mandate, EU Taxonomy alignment requirements for water-dependent sectors and the BBNJ Treaty's EIA provisions.

Blue bonds and blue finance instruments are gaining traction. The World Bank issued US$5 billion in blue bonds between 2018 and 2025, and the Belize Blue Bond, restructured in 2021 through The Nature Conservancy's debt-for-ocean swap, has funded 12,000 square kilometres of new marine protection (World Bank, 2025; TNC, 2025). The Asian Development Bank launched a US$500 million ocean finance facility in 2024 targeting coral reef restoration, sustainable aquaculture and coastal resilience across the Indo-Pacific (ADB, 2024).

Pricing for water stewardship outcomes remains less developed than for carbon or even terrestrial biodiversity credits. Pilot freshwater biodiversity credits in Australia's Murray-Darling Basin traded at AUD 1,200 to AUD 3,500 per unit in 2025, reflecting nascent supply and experimental demand (Australian Government, 2025).

Key Players

Established Leaders

• NatureMetrics — Global leader in eDNA-based biodiversity monitoring with over 50,000 samples processed and partnerships spanning regulators, corporates and conservation organisations.
• Alliance for Water Stewardship (AWS) — Operates the leading international standard for water stewardship, with 380 certified sites across 40 countries.
• The Nature Conservancy (TNC) — Manages global freshwater and marine conservation programmes including debt-for-nature swaps and dam removal pipelines.
• Marine Stewardship Council (MSC) — Certifies sustainable fisheries with over 500 certified fisheries supplying 15 percent of global wild-catch seafood.

Emerging Startups

• Aqua-T — Swiss eDNA analytics startup consolidating European laboratory capacity for aquatic biomonitoring.
• Subsea 7 Nature-Based Solutions — Engineering firm pivoting toward marine habitat restoration and offshore reef construction.
• Regen Network — Blockchain-based platform for ecological credit issuance and verification, expanding into marine and freshwater credits.
• Xylem Analytics — Water quality sensor and data platform enabling real-time monitoring of freshwater biodiversity indicators.

Key Investors/Funders

• Global Environment Facility (GEF) — Largest multilateral funder of marine and freshwater biodiversity projects, with US$1.4 billion deployed since 2022.
• Blue Nature Alliance — US$250 million partnership led by Conservation International and partners to catalyse ocean protection across 18 million square kilometres.
• Asian Development Bank — Launched a US$500 million ocean finance facility in 2024 targeting coral reef and coastal resilience.
• Mirova Natural Capital — Manages blue economy and natural capital investment strategies focused on sustainable fisheries and coastal restoration.

Sector-Specific KPI Benchmarks

Action Checklist

• Deploy eDNA monitoring at priority water sites. Start with sites adjacent to operations in high-biodiversity-value catchments. Use quarterly sampling to establish baselines and track trends.
• Map BBNJ Treaty exposure. Identify any supply-chain activities, shipping routes or sourced marine genetic resources that intersect with likely high-seas MPA designations or EIA requirements.
• Pursue AWS certification for water-stressed sites. Prioritise facilities in basins classified as "high" or "extremely high" water stress by WRI Aqueduct.
• Set context-based freshwater targets. Adopt the SBTN freshwater targets methodology to ensure water-related goals reflect local hydrological realities and ecological thresholds.
• Integrate aquatic biodiversity into TNFD reporting. Include marine and freshwater dependencies, impacts and restoration investments in nature-related disclosures.
• Explore blue finance instruments. Evaluate blue bonds, debt-for-ocean swaps and freshwater biodiversity credits as mechanisms for financing basin-level restoration.

FAQ

What is eDNA and how reliable is it for aquatic monitoring? Environmental DNA is genetic material shed by organisms into water. Modern eDNA metabarcoding can detect hundreds of aquatic species from a single water sample with sensitivity comparable to or exceeding traditional survey methods for many taxa. Reliability depends on sampling protocol standardisation, reference database completeness and environmental conditions. Warm, UV-exposed or highly turbid waters can degrade eDNA rapidly, so sampling design must account for these factors. ISO standards under development (expected late 2026) will provide international benchmarks for eDNA quality assurance.

How will the BBNJ Treaty affect private-sector operations? The treaty introduces mandatory environmental impact assessments for activities on the high seas, including deep-sea mining exploration, certain fishing operations and infrastructure deployment. Companies with high-seas operational footprints should prepare by conducting baseline environmental assessments, engaging with the treaty's scientific committee processes and monitoring the designation of high-seas MPAs that could restrict activity zones or shipping routes.

What distinguishes water stewardship from water efficiency? Water efficiency focuses on reducing consumption at the facility level, measured in litres per unit of production. Water stewardship takes a basin-wide perspective, requiring companies to engage with other water users, regulators and communities to address shared risks including ecological degradation, inequitable access and governance failures. AWS certification, the leading standard, requires site-level action plans that contribute to catchment-level outcomes.

Are freshwater biodiversity credits investable at scale? The market is nascent. Pilot schemes in Australia's Murray-Darling Basin and emerging frameworks in the UK and EU are testing credit structures. Scalability depends on standardised metrics for freshwater ecological gain, buyer demand linked to regulatory mandates or voluntary commitments, and MRV systems such as eDNA that can verify outcomes cost-effectively. The sector is likely two to four years behind terrestrial biodiversity credits in market maturity.

How should companies prioritise marine vs. freshwater biodiversity actions? Prioritisation should be driven by materiality. Companies with seafood supply chains, shipping fleets or offshore operations face direct marine biodiversity risks and should focus on MSC/ASC certification, BBNJ Treaty compliance and marine habitat restoration. Companies in agriculture, beverages, mining or textiles typically face greater freshwater biodiversity exposure and should prioritise basin-level stewardship, eDNA monitoring and SBTN freshwater targets. Many companies will need to address both domains.

Sources

• WWF. (2024). Living Planet Report 2024: Freshwater Species Trends. World Wildlife Fund.
• FAO. (2024). The State of World Fisheries and Aquaculture 2024. Food and Agriculture Organization of the United Nations.
• Deutz, A. et al. (2024). Financing Nature: Closing the Global Biodiversity Financing Gap. The Paulson Institute, The Nature Conservancy, and Cornell Atkinson Center for Sustainability.
• Grand View Research. (2025). Environmental DNA (eDNA) Market Analysis and Forecast 2025-2028. Grand View Research Inc.
• UK Environment Agency. (2024). eDNA Survey Requirements: Updated Guidance for Planning Applications. Environment Agency, UK.
• NatureMetrics. (2025). Global eDNA Platform: 50,000 Samples Milestone and Cost-Effectiveness Data. NatureMetrics Ltd.
• Thomsen, P.F. & Willerslev, E. (2025). "Large-Scale eDNA Metabarcoding of Norwegian Fjords." Marine Ecology Progress Series, 714, 45-62.
• Anglo American. (2025). Water and Biodiversity Report 2024: eDNA Monitoring Across Watersheds. Anglo American plc.
• Nestlé. (2025). TNFD-Aligned Nature Disclosure: Aquatic Biodiversity Monitoring at Bottling Sites. Nestlé S.A.
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• IISD. (2026). BBNJ Treaty Ratification Tracker: February 2026 Status. International Institute for Sustainable Development.
• High Seas Alliance. (2025). Protecting 30% of the Ocean: Priority Sites and Implementation Pathways. High Seas Alliance.
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• Diageo. (2025). Water Stewardship and Peatland Restoration: AWS Certification and Johnnie Walker Foundation. Diageo plc.
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