Identifying priorities for the protection of deep-sea species and habitats in the Nordic Seas

1.1 - The history of deep-sea exploration and research

The deep sea represents the most extensive biome on Earth, with about 95% of the planet covered by waters deeper than 200 m^4,5 . Although most seas surrounding Norway are shallow continental shelf seas (e.g., the Barents Sea with average depth of 230 m, the North Sea and Skagerrak both with average depth of 90 m), the Norwegian Sea has an average depth of 1800 m and holds a vast area (>260 000 km² ) that hosts deep-sea ecosystems^6–8. In 1876-1878 the Norwegian North-Sea expedition inaugurated the exploration of the Norwegian Sea (a previously uncharted ocean area between Norway, the Faroe Islands, Island, Jan Mayen and Spitsbergen) and described for the first time the seabed topography, oceanographic conditions and pelagic and bottom dwelling marine fauna at these vast ocean depths⁹ . A century later, efforts to map benthic fauna in the Nordic Seas (i.e., Norwegian Sea, Greenland Sea and Iceland Sea) were continued through the BIOFAR¹⁰ , BIOICE¹¹ and the IceAge¹² programs. The emergence of more advanced technologies, such as Remotely Operated Vehicles (ROVs) in the 2000s, considerably enhanced the degree of detail to which deep-sea habitats could be studied. These technologies revealed highly diverse and productive, nutritionally interconnected systems associated with ridges, seamounts and hydrothermal vent systems in the Northeast Atlantic Deep Sea^8,13–18. Recent ship-mounted multibeam mapping efforts have revealed the Norwegian Sea as much more topographically complex than previously assumed (Dybdedata, Geonorge) hosting a great variety of geological formations; seamounts, canyons, terraces, plateaus, etc., that generate unique environmental conditions and generally foster high biodiversity^19–23. Despite these technological advancements, the deep sea remains widely understudied, and many gaps persist in our understanding of its biodiversity and ecosystems. Predictive modelling efforts have demonstrated the high suitability of these complex areas for settlement and growth of habitat-forming corals and sponges²⁴, which are known to be highly sensitive to physical or mechanical pressures induced by human activities^24–28_.

1.2 - Human activities in the global deep sea

Until recently, the relative inaccessibility of the deep sea has limited the direct impacts of human activities on deep benthic species and habitats compared to most other ecosystems⁴. Therefore, the deep sea is often considered the last frontier of the Earth. However, technological advancements since the mid-2000s have enabled the expansion of deep-sea industries such as deep-sea fishing (>400 m), deep-sea oil and gas exploration and production, and deep-sea mineral exploration^29,30. Since the 1950s, it is unequivocal that the practice of deep-sea bottom trawling has severely or even irreparably damaged countless deep-sea coral reefs, coral gardens and sponge aggregations inhabiting the mid-ocean ridges and seamounts at a global scale^29,31. The impacts of deep-sea bottom trawling extend beyond benthic species and habitats, often targeting spawning or feeding aggregations of long-lived, slow growing, late maturing species. Consequently, this practice has led to the depletion of numerous fish populations such as the Orange roughy (Hoplostethus atlanticus) and the Slender armorhead (Pentaceros wheeleri)²⁹.

The hydrocarbon industry has targeted deep-sea oil and gas reservoirs since the mid-1990s. Since the beginning of the 21^st century the majority of new major oil and gas discoveries globally have been made in either deep (>500 m) or ultradeep (>1500 m) waters³². Environmental impacts from oil and gas exploration and production occur mainly in the drilling phase when large amounts of drill mud and cuttings are released into the near seabed environment³³. The majority of suspended particles tend to settle within a few hundred meters from the wellhead, usually resulting in spatially restricted impacts on benthic communities³³. Low concentrations of the drill mud may disperse several kilometers away from the wellhead³¹. Recent studies demonstrated that impacts of suspended sediment plumes on long-lived structure-forming corals may be severe³⁹. Furthermore, studies have shown much longer recovery times of deep-water benthic communities after being impacted from settling drilling mud as compared to more shallow water benthic communities³⁴. The 2010 Deepwater Horizon oil spill in the Gulf of Mexico also demonstrated that accidental releases of hydrocarbons in near the seabed severely impacts deep-sea corals³⁵.

Marine mining has not yet been realized in the high seas or in any nation’s Exclusive Economic Zone (EEZ), primarily due to a general lack of environmental and biological baseline data, as well as a limited understanding of potential environmental impacts^36,37. Consequently, the industry currently lacks societal legitimacy³⁸.

1.3 - Human activities in deep waters of the Nordic Seas

Currently, there is only limited human activities in the deeper parts of the Nordic Seas. Oil and gas extraction occur mainly in shallow waters with the exception of Ormen Lange (at 850-1100 m) and Aasta Hansteen and IRPA (at 1300 m) gas fields. There is only limited bottom fishing taking place below 500 m. Additionally, in Norwegian EEZ (including the fisheries zones around Svalbard and Jan Mayen), all bottom fishing has been prohibited to protect vulnerable marine ecosystems from severe harm (regulation from 2011, Forskrift om endring i forskrift om regulering av fiske med bunnredskap i Norges økonomiske sone, fiskerisonen rundt Jan Mayen og i fiskevernsonen ved Svalbard - Lovdata). This area can therefore be considered protected under Other Effective Area-based Conservation Measures (OECMs) against bottom fishing. However, this protection is limited to threatening activities identified at the time of implementation and will not include other unregulated human activities^40,41. In June 2023, a request to open the Norwegian continental shelf for commercial mineral exploration and extraction was proposed by the government to parliament⁴² . This raises concerns of the potential impacts of the development of this new industry on deep-sea ecosystems where minimal previous economic activity has occured^8,43, as this activity is considered among the most invasive and destructive of human activities. Norwegian parlament granted exploration for minerals in the area, on January 9th 2024 (Regjeringen.no). If extraction is permitted, deep waters of the Nordic Seas will not be considered protected under OECMs against mineral excavation, and therefore will be vulnerable to complete habitat removal⁴⁴ .

1.4 - MPAs and marine spatial planning

The establishment of Marine Protected Areas (MPAs), wherein human activities are restricted or entirely prohibited, has proven to be a key management and regulatory tool in mitigating biodiversity loss, especially by providing refuges for populations of vulnerable species^45–49_. The implementation of MPA networks, composed of a collection of individual areas that are ecologically connected, also represents an important conceptual approach for the management of marine species and ecosystems^45,50_. Within well-designed networks, MPAs can be managed to reach specific objectives, while complementing each other and cumulatively ensuring ecosystem connectivity and sustained provision of functions and services across large spatial scales⁵¹ . Not only can this approach produce superior conservation benefits to single, isolated MPAs, but also may be more adaptable to minimize socioeconomic impacts without compromising these benefits. As stated in the white paper “Stortingsmelding 20 - Norway´s integrated ocean management plan” the government’s objectives are oriented towards the establishment of representative MPAs in Norway´s coastal and marine waters and provide a representative network that maintains the full range of habitat types found⁴². The COP15 Kunming-Montreal Global Biodiversity Framework (ratified by Norway in December 2022) targets that at least 30% of land and sea areas, especially areas of particular importance for biodiversity, are conserved through effectively and equitably managed, ecologically representative and well-connected systems of protected areas and OECMs, and integrated into the wider landscapes and seascapes¹. Currently, about 8.2% of the world’s oceans (www.protectedplanet.net/marine) and approximately 5% of Norwegian waters are covered by MPAs. Norway’s existing MPA inventory was implemented as part of a marine protection plan drafted in 2004, and comprises 36 representative MPAs placed exclusively in coastal waters. In addition, a large part of the Norwegian seabed is protected though OECMs in fisheries legislation.

In this context, the primary objective of this report is to propose a representative network of MPAs within the NECS (Norwegian Extended Continental Shelf), based on the available knowledge as of the time of this report’s writing, aiming to mitigate potential future anthropogenic impacts on deep-sea benthic ecosystems. This has been actualized with the government’s recent proposal to the parliament to open the continental shelf for mineral exploration and exploitation⁴². The deep-sea area of interest (i.e., our study area) was defined as all the seabed of the continental slope and the abyss belonging to the NECS (Figure 1). Here, we aimed 1) to identify priority areas for the protection of geomorphic and biological features and 2) to propose a representative network of MPAs, following the principles for MPA network design provided by CBD and Oslo-Paris Convention (OSPAR)^2,52. The principles are internationally established and are used by the International Seabed Authority to establish no-mining areas in ocean regions where licenses for deep-sea mineral exploration have been commissioned (e.g., in the Clarion-Clipperton Fracture Zone).

All publicly available scientific data were collected for the area of interest. This comprised biogeographic regions and provinces⁵⁵, geomorphic features and marine landscapes²² (e.g., canyons, ridges, seamounts, hydrothermal vents) and biogenic habitats (e.g., abundance and diversity of cold-water coral communities and sponge aggregations). The description, definitions and sources of all the layers and data used in this study are given in Appendix.

2.1 - Study area

The ocean area north of the Greenland-Scotland ridge, south of the Fram Straight and Spitsbergen Island, and west of the continental slope to the shallow Barents Sea is generally referred to as the Nordic Seas. This region comprises the Norwegian Sea, Iceland Sea and Greenland Sea, covering approximately 2.6 million km². It has an average depth of 1600 mn with its deepest point, Molloy Dypet, reaching a depth of 5569 m. The area is characterized by remarkable heterogeneity, with shallow continental shelfs and slopes, vast abyssal plains (i.e., Boreasbassenget, Grønlandsbassenget, Lofotenbassenget and Norskehavsbassenget), the Arctic Mid Ocean Ridge (Kolbeinsey Ridge, Mohn´s Ridge and the Knipovich Ridge), seamounts (>1000 m elevation), plateaus, canyons and ravines. Here, the deep-sea area under consideration was defined as all the seabed of the continental slope and the abyss belonging to the NECS and represents a total surface of 1 231 981 km² (Figure 1).

2.2 - Identification of priority areas for protection

2.2.1 - Conservation targets for priority areas

The selection of priority areas was based on different characteristics, such as their uniqueness or rarity; special importance for life-history stages of species; importance for threatened, endangered or declining species and/or habitats; vulnerability, fragility, sensitivity or slow recovery, structural complexity; biological productivity; and diversity. The MPA network was designed to capture 100% of priority areas for protection, in this case comprising all known hydrothermal vents and cold seeps, hotspot communities of cold-water corals (CWC) and sponge aggregations, as well as one species of Siboglinidae worm (Sclerolinum consortum) assessed as vulnerable on the Norwegian Red List of Species. Cold-water corals and deep-sea sponges are generally characterized by long lives, slow growth and irregular recruitment, all of which contribute to slow recovery of damaged habitats. They form habitats that are utilized by other species, thereby contributing to increased biodiversity and productivity within the ecosystem^7,8. Cold seeps and hydrothermal vents both host rare and unique communities of chemo-synthesizing microorganisms and invertebrates. All of these habitats are considered fragile and highly sensitive to physical disturbance^7,8 .

2.2.2 - High Diversity or Abundance Areas (HDAA)

During the network design process, the protection of 100% of CWC and sponge aggregations challenged the representativity of the network due to the uneven distribution of these aggregations that may be partly compounded by uneven habitat mapping effort within the study area. Within Norwegian waters, some areas exhibited a high number of CWC and sponge observations, particularly in the southern part of the continental slope. Comparatively, fewer observations have been made in other locations, including deep-sea areas below the continental slope and the northernmost part of the continental slope (Figure 2). To date, most of research efforts to map CWC and sponges have focused on Norway’s continental slope (through the MAREANO program), leaving their distribution in the deep-sea areas below the continental slope and the northernmost part of the study area uncertain. Therefore, fewer CWC and sponge observations in these areas do not necessarily imply the absence of these habitats but may, in fact, be attributed to insufficient mapping data. Ensuring 100% protection of all recorded observations of CWC and sponges could lead to representativity and connectivity issues within the network, as data deficiencies in certain areas of the NECS will inevitably bias the results of conservation planning models.

To address this issue, diversity (number of coral and sponge habitat types) and abundance (number of CWC and sponge observations) criteria were used to define high-diversity or abundance areas (HDAAs) of CWC and sponge aggregations. High-diversity areas were defined as locations containing four or more CWC and sponge aggregation types per 100 km² (Figure 2A), while high-abundance areas are locations with more than 40 observations of CWC and sponge aggregations per 100 km² (Figure 2B). Consequently, CWC and sponge HDAAs received full protection when designing the MPA network. CWC and sponges not included in HDAAs were considered as part of low-diversity and abundance areas (LDAAs) and were protected according to general conservation targets (30%, 40% or 50%, depending on the chosen scenario). Finally, CWC and sponges not included in the MPA network were subjected to specific conservation rules, presented below (cf. §3.3).

2.3 - Identification of features and areas not classified as priorities

The NECS encompasses several biogeographic provinces⁵⁵, marine landscapes (as defined by the Geological Survey of Norway; NGU), and geomorphic features²², which are not considered here as priority areas for protection (Appendix). These areas and features are characterized by different environmental conditions (temperature, substrate, depth, etc.) that interact and affect species distribution. The fundamental niche represents all the environmental conditions under which a species can establish, survive and reproduce. Collecting information on the fundamental niche therefore informs on the potential distribution area of a species, which may be close to the actual species distribution.

Hence, protecting known fundamental niches is recognized as a useful strategy to ensure that representative habitats are protected in areas lacking data⁵⁶. During the network design process, features and areas not classified as priorities  were protected according to general conservation targets (30%, 40% or 50%, depending on the chosen scenario).

2.4 - MPA network design

The MPA network was designed using the conservation planning software Marxan^53,54. The design process relied on the consideration of five network criteria, identified by the CBD^1,2_. Priority Areas for Protection, Representativity, Replication, Connectivity, and Adequacy and Viability (Table 1). In accordance with these criteria, we evaluated different scenarios of MPA networks, protecting 50%, 40% and 30% of the study area. For each scenario, the model tested a predefined number of potential solutions in each run (set at 100 by default), then used a scoring system to propose an optimized solution. It is important to emphasize that Marxan operates as a highly effective decision support tool, and its role is to assist in the decision-making process rather than make definitive decisions. In order to accommodate the complexities inherent in both the socioeconomic and ecological dimensions of the planning area, it is considered best practice to subject Marxan outputs to human oversight and to make adjustments when necessary.

3.1 - Selection of a network

A number of different MPA network scenarios were assessed protecting 50%, 40% and 30% of the study area. The 40% and 50 % scenarios were chosen following empirical evidence that 40-50% protection is the minimum coverage needed to fully protect the range of biodiversity³ and threatened species within a given area. The 30% protection scenarios were assessed as, in ratifying the COP15 Kunming-Montreal Global Biodiversity Framework¹, Norway has committed to ecologically-coherent conservation of 30% of its ocean area by 2030 which will serve to mitigate further biodiversity loss in alignment with CBD objectives. The specific percentages of protection assigned to the different features in these scenarios are detailed in Table 2.

The first scenario presents an MPA network with a protection target of 50%. It covers 670 567 km², which represents 54% of the study area (Figure 3A). This network comprises 10 MPA units that range from 88 to 253 499 km² in size. The second MPA network was designed with a protection target of 40% (Figure 3B). This scenario is composed of 16 MPA units, ranging from 85 to 98 819 km², covering a total of 524 583 km², which represents 43 % of the study area.

Three different MPA network scenarios were generated to achieve a 30 % protection target within the study area (Figure 4):

• The scenario 30%A (Figure 4A) consists of 16 MPA units ranging from 100 to 97 061 km². This scenario covers 467 721 km², which corresponds to 38% of the study area.

• The scenario 30%B (Figure 4B) comprises 11 MPA units ranging from 100 to 160 828 km², covering a total of 509 351 km², which represents 41% of the study area.

• The scenario 30%C (Figure 4C) encompasses 22 MPA units with sizes ranging from 85 to 77 242 km². These MPAs collectively cover 407 968 km², representing 33% of the study area.

While all three scenarios successfully achieved the minimum conservation targets for all features, scenario 30%B notably exceeded the required protection levels for several of them (e.g., fans +35%, rift valleys +44%, troughs +52%) (Table 2). Scenario 30%A also conferred substantial protection to numerous features, up to +30% for rift valleys (Table 2). Among these scenarios, the 30%C MPA network emerged as the most favorable, as it met the minimum conservation targets for nearly all features (except for the Barents Sea: -12%), and exhibited only a few features exceeding the conservation targets by more than 20% (Norwegian Coast: West Norway, sill, fans) (Table 2). All MPA scenarios presented herein were designed to represent the range of species, habitats and geomorphic features occurring in the study area in the best possible way. A primary objective was to prevent degradation and damage to species, habitats and ecological processes, adhering to the precautionary principle. Consequently, the implementation of MPA network scenario 30%C emerges as a suitable management strategy to curtail anthropogenic impacts on deep-sea benthic ecosystems. Further work using bio-physical modelling and network analysis to fully assess the connectivity between the suggested MPA network scenarios are, however, recommended before steps are taken for the implementation of an MPA network.

3.2 - Implementation of buffer zones

The drilling of offshore oil and gas wells and deep-sea mining are likely to generate high-turbidity, far-reaching and potentially toxic sediment plumes that can alter the structure and function of marine ecosystems^{33,36,57–59}. In this context, buffer zones aiming to shield the core MPAs from the effects of sediment plumes generated by deep-sea industries in adjacent areas are commonly applied. This report introduces four different sizes of buffer areas: 1 km, 5 km, 10 km and 20 km surrounding each core MPA unit (Figure 5). The proposed buffer zones are based on the expected degree of impact from sediment plumes generated by deep-sea industries. The intent is to provide alternatives based on the current state of knowledge to facilitate informed decision-making in the implementation of these zones.

For the 30% C scenario, the inclusion of 1 km, 5 km, 10 km and 20 km buffer zones around each core MPA unit increased the coverage of the overall network area by 2%, 5%, 8% and 16%, respectively. Existing literature suggests that a 1 km buffer zone may be insufficient to adequately shield MPA core units from sediment plumes generated by deep-sea industries^60,61. Conversely, 20 km buffer zones afford substantial protection to core areas, presenting a notably low risk of impact from sediment plumes. However, it is noteworthy that these buffer zones considerably increase the size of the MPA network beyond what has been determined necessary to mitigate impacts from sediment plumes on ecosystems within each MPA unit, and thus may not significantly increase the conservation value of the network compared to 10 km buffers. Uncertainty remains due to the lack of data regarding the impact of sediment plumes generated by deep-sea industries on benthic species and habitats. In light of these considerations, buffer zones between 5-10 km may represent an optimal alternative for mitigating most of the sedimentation risk without significantly increasing the size of MPA units. Pending further investigations into the behavior of sediment plumes generated by deep-sea industries and their impact on marine ecosystems, the implementation of a 10 km buffer zone around each MPA unit is recommended as a precautionary measure. This would expand the MPA network coverage to 528 128 km², with 510 199 km² situated within the study area (covering 41% of the study area). Notably, since some MPA core units are situated along the perimeter of the NECS, 17 929 km² of buffer zones extend beyond the study area (for the 10 km buffer zone). In these instances, Norwegian sovereignty would not apply. Nonetheless, their consideration is deemed essential to ensure that deep-sea activities conducted outside of the study area (including those on the continental shelf of other sovereign nations, in ABNJ or within the Norwegian shelf) do not impact the MPA core units situated within the NECS.

3.3 - Considerations for features outside the MPA network

3.3.1 - CWC and sponge aggregations

In the 30%C scenario, all CWC and sponge aggregations encompassed within HDAAs were included in the MPA network. Additionally, the MPA network and its 10 km buffer zone comprise 92% of CWC and sponge aggregations not classified as HDAAs, with the remaining 8% of these located outside of the MPA network. Though excluded from the network by the model, we argue that these aggregations are nonetheless ecologically important and recommend that no activity that could result in their total or partial destruction should be permitted near their location. The management approach will require in-depth investigations conducted on a case-by-case basis to evaluate the potential risks of impact from deep-sea industries on CWC and sponge aggregations.

3.3.2 - New discoveries

The present MPA network proposal is grounded in the available knowledge as of the time of this report’s writing. It is essential to acknowledge that the diversity of deep-sea species and ecosystems in the Nordic Seas remains only superficially surveyed, with the majority of these lacking detailed mapping of the seafloor. The application of predictive models to forecast the distribution of unique benthic species and habitats can contribute to the identification of areas where they are likely to be found and guide targeted sampling and conservation efforts²⁴ . Both ongoing and forthcoming research initiatives are expected to enhance our knowledge of the distribution and ecological functioning of deep-sea benthic species and habitats within the study area. Therefore, the implementation of adaptive management practices will be essential. During exploration activities, conducted by research programs or by deep-sea industries alike, the discovery of new deep-sea species or ecosystems that fall within the realm of priority areas for protection (e.g., hydrothermal vents, cold seeps, HDAAs for CWC and sponge aggregations) may warrant adjustments of the management plan or MPA design. The discovery of CWC and sponge aggregations of low diversity and abundance should be assessed on a case-by-case basis. In the event of a significant discovery of species or ecosystems classified as priority areas for protection due to their rarity, a reevaluation of their status will be necessary. New discoveries of high significance may necessitate a reassessment of the MPA network design to optimize its efficiency to conserve deep-sea benthic biodiversity and ecosystem functions. Local discoveries made outside the proposed network could be integrated as small MPA units in the network.

Here, we presented the outline for a network of MPAs serving to conserve unique and representative deep-sea benthic species and habitats in the NECS, following internationally-aligned and applied principles. The call for the implementation of such a network is timely. The recent ratification of the 2022 Global Biodiversity Framework, calling on nations to halt biodiversity losses by accelerating the establishment of MPAs and implementing OECMs in their waters, has catalyzed the need for Norway to scrutinize available knowledge to identify priority areas for protection. Furthermore, the existing request from the government to parliament to open the Norwegian shelf for deep-sea mining has raised significant concern regarding its potential impacts on deep-sea benthic habitats. The establishment of an MPA network would serve as a precautionary approach to environmental management in the face of the many uncertainties attached to deep sea mining development. This is a critical and responsible step as the deep-sea mining industry is still in the early stages of development, and knowledge of the severity and spatial extent of mining impacts (i.e., dispersal of sediment plumes, sensitivity of ecologically relevant species) remains limited.

A recent report has identified Ecologically and Biologically Significant Areas (EBSAs; referred to as “Særlig Verdifulle og Sårbare Områder” (SVOs) in Norwegian) for Norway’s management plan areas⁷. EBSAs represent special areas in the ocean that serve important purposes, in one way or another, to support the healthy functioning of oceans and the many services that it provides². EBSAs and MPAs have similar selection criteria, defined by the CBD⁷, but differ in terms of their legal protection framework. While EBSAs are mainly strategic and advisory, highlighting the importance of showing particular care in these areas⁷, MPAs represent a regulatory tool that restricts or prohibits human activities². Together they represent valuable and complementary management tools aimed at ensuring the maintenance of ecosystems diversity and functioning. For instance, the selection of EBSA in deep-sea habitats can guide the identification of marine areas in need of protection². In their report, Eriksen et al. (2021) identified EBSAs by considering benthic and pelagic species and ecosystems, as well as observed and predicted species/habitats distributions. Here, the MPA network was designed solely based on observed and/or measured data of benthic species and habitats, falling under Norway’s jurisdiction. Considering only EBSAs that serve important purposes to support the healthy functioning and services of benthic communities (NH1 and NH2 excluded) and lie within the study area of the present report, these areas cover approximately 540,000 km² (Figure 6). Our aim is for the proposed MPA network to complement the previous EBSA work and contribute to more efficient conservation of biodiversity and ecological functioning in the deep Nordic Seas.

The design of the proposed MPA network is based on the reported importance of known species and habitats (identifying priority areas for protection) as well as representativity, replication, adequacy and viability criteria. Through a comparative assessment of different MPA network scenarios, one is recommended (30%C; Figure 4C) comprising 22 MPA units and covering 33% of the study area. This scenario encompasses 35% of EBSAs that serve important purposes to support the healthy functioning and services of benthic communities in the study area. This network meets the conservation targets for all specified geomorphic features, seascapes, and biogenic habitats identified in deep waters of the Nordic Seas, without significant overrepresentation (see Table 2). It protects 100% of all known active and inactive hydrothermal vents and cold seeps, and 100% of the areas defined as coral and sponge hotspots. Further, the implementation of 10 km buffer zones is recommended to minimize the impacts of particulate matter and contaminants on core areas, placing restrictions for industrial activities. With 10 km buffer zones, the 30%C scenario covers 41% of the study area, and approximately 33% of the proposed area for commercial mineral exploration and extraction⁴² (Figure 6). Comparatively, about 44% of the planning area of the Clarion-Clipperton Zone (CCZ) in the Pacific Ocean, where hydrocarbon mining is expected to take place, has been reserved through a network of 13 protected areas (i.e., Areas of Particular Environmental Interest) by the International Seabed Authority as part of their spatial management plan for the CCZ⁶⁶. The 30%C scenario and its 10 km buffer zones also encompasses 43% of EBSAs that serve important purposes to support the healthy functioning and services of benthic communities in the study area.

Studies from the CCZ have demonstrated that it is vital that MPAs are established before licenses for industrial activities are granted in order to afford sufficient protection to all targeted habitat types within the study area. If not, there is a risk that MPAs may not sufficiently protect all targeted habitats representatively^67,68,69 or that some habitats may not be protected at all, increasing the probability of biodiversity loss and species extinctions⁴⁴. Without careful consideration and reevaluation of the spatial management plan of deep waters of the Nordic Seas, Norway may well fail to meet key goals in the COP15 Kunming-Montreal Global Biodiversity Framework. These goals include halting human induced extinction of known threatened species, reducing the global species extinction rate tenfold by 2050, restoring the abundance of native species to healthy and resilient levels, and ensuring the sustainable use and management of marine natural resources so that humans can continue to rely on ecosystem functions for generations to come.

Beyond the already mentioned benefits, the establishment of this deep-sea MPA network would also ensure that Norway meets its commitment to assist the OSPAR Commission in reaching its conservation target for the Arctic Waters (OSPAR region I). The Northeast Atlantic Environment Strategy (NEAES) goal for OSPAR member states (which includes Norway) is to further develop the OSPAR MPA network in the northeast Atlantic so that representative MPAs and OECMs cover at least 30% of the OSPAR maritime area by 2030. As of October 2021, the OSPAR Network of MPAs included 583 MPAs, covering 11% of the OSPAR Maritime Area, with a total surface area of 1 490 552 km². Arctic Waters (Region I) have the lowest protection rates by far with just 2% MPA coverage. The acceptance of the network proposed herein would substantially contribute to the NEAES objective of increasing the MPA network cover of the OSPAR maritime area to a total of 1 898 520 km² (i.e., 14% of the OSPAR maritime waters) and to 515 814 km² (i.e., 9%) for Arctic Waters (OSPAR region I).

We expect that this knowledge review and the spatial analysis presented here will serve as a meaningful contribution to the discussion on how Norway should approach meeting its COP15 30x30 conservation commitments. Timely discussion of the conservation and protection needs of deep waters of the Nordic Sea would significantly strengthen Norway’s reputation as a nation driving both the development and the implementation of knowledge-based management of marine resources and ecosystems. Still, given the current lack of knowledge regarding the distribution, structure and functioning of deep-sea benthic ecosystems of the NECS⁸, we strongly recommend an intensified research and mapping effort over the next decade. This initiative should align closely with the government's plans to develop a comprehensive strategy for establishing a MPA network. This would improve the ability for informed management decisions in the NECS to be made, both in terms of conservation and development planning.

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