The high seas – defined by the United Nations (1982) as open ocean waters that lie beyond the economic zones and jurisdiction of any one country – account for two-thirds of total ocean area. The world’s largest ecosystem, the high seas are home to some of the least well-known and most unique biodiversity on Earth (Ramirez-Llodra et al., 2010). Over the past few decades, fishing and mineral exploitation has expanded into the high seas because of the overexploitation of coastal waters, increasing demand driven by growing populations, the availability of government subsidies, and technological innovation that has enabled access (Swartz et al., 2010; Sumaila et al., 2015).

Because there is no universal law protecting biodiversity, the high seas are very vulnerable to exploitation. Just one percent is closed to commercial use. Overfishing, deep sea mining projects, and climate-related effects of ocean warming and acidification threaten unique deep sea and benthic communities (Ramirez-Llodra et al., 2011; Clark et al., 2016). The depth of the high seas, with little light and food available, provides habitat for fishes that are long-lived and slow growing, characteristics that make them particularly vulnerable to overexploitation and extinction.

Since the 1990s, the most significant human-caused damage to deep sea ecosystems is associated with fishing (Rameriz-Llodra et al. 2010). Inadequate management of the high seas has led to the overfishing of many economically important fish stocks (Cullis-Suzuki & Pauly, 2010) and these fisheries are also responsible for the by-catch of threatened or vulnerable species, widespread habitat destruction by trawling, and ghost-fishing by discarded nets (Rameriz-Llodra et al., 2010). Heavy trawling reduces the diversity and biomass of critical habitat-forming species, such as corals, with limited recovery even decades after fishing has ceased (Althaus et al., 2009). Overfishing of a number of highly migratory pelagic species such as tunas and billfishes are particularly worrying. Stocks of tunas and their relatives have declined on average by 60% during the last half century and the majority of these stocks are now either fully exploited or overexploited (Juan-Jorda et al., 2011).

Meanwhile, the mining of deep-sea minerals is a rapidly developing enterprise; the International Seabed Authority (ISA) has recently granted the first licenses to 29 mining contractors, with commercial exploitation expected to begin in the next five years. A single mining operation is projected to remove nodules and near-surface sediments from 300 to 700 km2 of seafloor per year, causing near total mortality in the area directly mined. Re-deposition of sediments disturbed by mining activities will disturb seafloor communities over an area perhaps two to five times greater. Over a 15-year period, a single mining operation could severely damage abyssal communities over an area of 50,000 km2 and three mining operations might disturb a seafloor area half the size of Germany (Ramirez-Llodra et al., 2010).

Despite the technological advances that enable fishing and mining at great depths, the vast majority of the deep ocean remains unexplored and poorly understood (Ramirez-Llodra et al., 2010). As a result, the overall ecological impacts of these threats and the large-scale changes to population dynamics are also largely unknown.

To fill the gap in governance, the United Nations is developing a legally binding instrument to protect marine biodiversity on the high seas: Biodiversity Beyond National Jurisdictions (BBNJ).

UN member states have agreed that the negotiations for the BBNJ will focus on four priority areas:

1. Marine genetic resources;
2. “Area-based management tools” such as marine protected areas (MPAs);
3. Environmental impact assessments; and
4. Scientific capacity building and the transfer of marine technology.

International collaboration, and the development and deployment of new technologies is crucial to build capacity, fill gaps in knowledge, and enable a science-based approach to the conservation and sustainable use of biodiversity under BBNJ. Genomic tools and techniques have the potential to make the UN treaty more affordable and effective, lowering both the burden of regulating UN treaty for states and the burden of compliance for commercial fishing and mining interests.

The United Nations began in 2018 to lay the foundation for a binding international legal instrument for governing the conservation and sustainable use of biological diversity in areas beyond national jurisdiction. (The second session of the intergovernmental conference was taking place at the time of this writing, and the treaty is slated to go into effect in 2020.)  As described above, the sessions are focused on developing a multi-tiered treaty with which to protect and equitably share marine genetic resources by employing “area-based management tools” to conserve biological diversity and environmental impact assessments to determine the sustainability of fishing, mining, and other extractive commercial operations. Protecting and sustainably using the high seas is ultimately dependent on understanding the high seas ecosystem, and conserving and managing ocean resources requires incorporating scientific advice into policy-making decision. Deploying new technologies in service of these goals will require transferring technology to developing countries. Therefore, building scientific capacity in all UN members states is an essential piece of this treaty.

A key question for conservation use cases is what species are present?

The development of DNA barcoding using short fragments of DNA to identify species overcomes some of the limitations of traditional morphological taxonomy (Hebert et al. 2003). The combination of DNA barcoding with high throughput sequencing of environmental DNA (eDNA metabarcoding) represents a new potentially powerful tool for the study of biodiversity, including in remote locations (Taberlet et al. 2012, 2018; Pedersen et al. 2015). eDNA combined with barcoding enables the rapid detection of species diversity and the presence of specific organisms or biological toxins from water samples.

Genomic tools and techniques have the potential to make the UN treaty more affordable and effective. Genomic tools have the potential to complement these new technologies to provide much-needed data on biodiversity in the high seas. Genomics can distinguish species through genetic barcoding, provide information on linkages among populations of a given species through population genetics, and identify adaptations to specific environments through sequencing approaches.

In the context of the BBNJ, eDNA has the potential to provide:

• A rapid and cost-effective protocol to describe a comprehensive picture of presence or absence of existing biodiversity in the high seas, allowing the identification of marine genetic resources and baselines for prioritization and evaluation of protection strategies.
• Rapid, cost-effective environmental impact assessments, better informed spatial plans for the high-seas, and monitoring of the biological impacts of extractive uses in near real-time.

Marine research institutions are attempting to develop technology that can remotely sample eDNA and couples this sampling with edge machine-learning techniques and high-performance computing for near-real time analysis of samples taken from remote parts of the ocean.

eDNA for Environmental Impact Assessments of Mining to Protect the High Seas:

Deep sea mining threatens benthic and deep-water marine biodiversity, yet the high high seas are a major potential source of mineral resources. The International Seabed Authority (ISA) has recently granted the first licenses for deep sea mining, with commercial exploitation expected to begin in the next five years. How to regulate international mining presents major difficulties; creating impact assessment methods for mining alone is a huge challenge. The ISA, the international regulator, works with a small annual budget of less than $9 million, and the cost of monitoring international mining efforts on the high sea is prohibitive. At present, the ISA is almost entirely dependent on the mining contractors it regulates for information regarding the deep seas. Its limited budget prevents any more active role in collecting data or initiating a robust impact assessment methodology.

However, new genomic technology has the potential to make regulation far more affordable and effective. Such technology would lower the financial burden to enable a cost-effective assessment method under the BBNJ UN treaty for commercial mining interests. The development of eDNA technology would to provide the ISA with a low-cost and updated monitoring tool capable of providing the raw material needed for robust enforcement of regulations and for strong and independent audits.

Several laboratories and marine research institutions are attempting to develop technologies that sample eDNA, coupling it with modern machine learning and data processing capabilities. The Monterey Bay Aquarium Research Institute (MBARI) is a leader with their Environmental Sample Processor, but other labs are also aspiring to develop similar technology. Furthermore, the development of this technology could allow regulators to monitor and evaluate the biological impacts of extractive uses in real-time for enforcement of regulations.

An eDNA-based monitoring tool could be uniquely suited to the ISA’s regulatory needs for independent environmental assessments and enforcement of seabed mining permits. This technological advancement could provide regulators with the ability to assess biodiversity much more cost effectively than the current manned expeditions that rely on video capture. With this technology, ISA and by extension the BBNJ, would for the first time be empowered to establish baselines of biodiversity, audit, monitor, and enforce regulations such as impact assessments pertaining to the extraction of deep-sea minerals and thus avoid activities that unreasonably damage deep sea ecosystems. The continued development of eDNA technology could be transformative by increasing metrics of high seas biodiversity as well as the economic feasibility and practicality of assessment methods. However, it is important to note that there are many steps and milestones that need to occur for successful implementation.

A number of challenges will need to be overcome for the development and implementation of the BBNJ and for the use of genomic tools in supporting the treaty. As such, genomics should be seen as one small part of the solution, alongside policy mechanisms and traditional conservation methods like mapping, satellite monitoring, and patrols.

The high level of unknown biodiversity in many deep-sea environments will require baseline assessment in high priority areas.

Given the deep sea is severely under-sampled (Ramirez-Llodra et al., 2010), molecular databases (e.g. GenBank, Barcode of Life) required for assigning species and identifying ecosystem services to sequences will require development in order for genomic technologies to be functional. However, additional molecular tools (e.g. metagenomics, metatranscriptomics, metabolomics) promise to be helpful in addressing these challenges.

The large size and remoteness of the high seas will require careful prioritization and cooperation to maximize return on effort for implementing any data collection, area management programs, or environmental impact assessments.

The sparse and fragmentary governance frameworks currently in place will require significant negotiation and will likely evolve over time for particular sectors and regions, as such the BBNJ should be considered the first step on this road.

The high cost and technological challenge to collect these data will require international cooperation and technology transfer in the form of basic research, data-sharing, training, and enhanced access to novel tools.

Monterey Bay Aquarium Research Institute (MBARI)
The mission of MBARI is to achieve and maintain a position as a world center for advanced research and education in ocean science and technology, through the development of better instruments, systems, and methods for scientific research in the deep waters of the ocean.

Schmidt Ocean Institute
Schmidt Ocean Institute works to advance the frontiers of global marine research by providing state-of-the-art operational, technological, and informational support to the pioneering ocean science and technology development projects at sea.

Professor Marcel Jaspars, University of Aberdeen
Research in the Jaspars group focuses on the functions and applications of natural products, particularly from marine organisms. The goal is determining the biological role of selected natural products and the potential for their use as pharmaceuticals and tools for biomedical research. Professor Jaspars established the Marine Biodiscovery Centre, a £1.6 million ($2 million) investment bringing together scientists from different disciplines to investigate how marine resources can be used for novel pharmaceuticals and to investigate chemical ecology and biosynthesis.

Dr. Maria Baker, Senior Research Fellow, University of Southampton
Dr. Baker is the project manager of INDEEP (International Network of Scientific Investigations of Deep-sea Ecosystems). This program aims to develop and synthesize our understanding of deep-sea global biodiversity and functioning across all habitats and provide a framework to bridge the gap between scientific results and society to aid in the formation of sustainable management strategies. She is also project manager of DOSI (Deep Ocean Stewardship Initiative). DOSI seeks to integrate science, technology, policy, law and economics to advise on ecosystem-based management of resource use in the deep ocean and strategies to maintain the integrity of deep-ocean ecosystems within and beyond national jurisdictions.

Professor Craig Smith, University of Hawaii
Professor Smith’s research includes biodiversity, disturbance ecology, and human impacts in seafloor ecosystems. He has conducted research in Antarctica, mangroves, submarine canyons, organic-fall communities, cold seeps, continental slopes, and abyssal plains. He has led over 50 research expeditions and has conducted over 100 HOV, ROV, and AUV dives. He has also published over 140 papers on seafloor ecology, biodiversity, climate-change impacts, and the design of marine protected areas, including at proposed deep-sea mining sites. Professor Smith has used eDNA for new approaches to assess biodiversity and ecological functions of microbes and animals living in sediments, on manganese nodules, and in the waters above.