Introduction
Bottom trawling is a highly effective method of fishing, which involves towing a net along, or just above, the ocean floor to catch bottom-dwelling species, including cod and shrimp. However, bottom trawling is also known for destroying the habitat of these species and carrying a large percentage of by-catch (Ciccariello, 2023). These environmental consequences raise questions about the adequacy of the international and European Union fisheries regulation to protect marine species. This article seeks to examine EU legislation on bottom trawling in the high seas, as well as whether the Union complies with its obligations under Article 117 UNCLOS for the conservation of the living resources of the high seas.
International Obligations
The European Union is a party to the United Nations Convention on the Law of the Sea (UNCLOS), a legally binding treaty established for the protection of the marine environment and for the resolution of maritime disputes. Article 116 of the Convention (1982) establishes the right to engage in fishing on the high seas, while Article 117 lays out the duty to adopt measures for the conservation of the living resources of the high seas, and Article 118 imposes cooperation duties on States in the conservation and management of these resources. Under Article 86 UNCLOS, the high seas comprise waters outside States’ exclusive economic zones, territorial seas, internal waters and archipelagic waters. Article 57 provides that an EEZ may extend up to 200 nautical miles from the baselines (UNCLOS, 1982, Art 58). While fishing is permitted on the high seas, it is not an absolute right, and the protection of marine life must be considered. The specific way that this must be done is not outlined in UNCLOS; it is left up to the parties. The continuous use of the words ‘living resources’ in section 2 of part VII is particularly important, because it implies that the provisions apply only in relation to those fishing stocks that can be harvested (Barraclough, 2024). Subsequently, in Article 145, UNCLOS uses the phrase ‘protection of the marine environment’ in the context of seabed mining. The use of this broader terminology may suggest that UNCLOS distinguishes between provisions governing exploitation of marine resources and those addressing the protection of the marine environment generally, and that it applies a more stringent standard for some forms of exploitation over others.
As a party to the United Nations Fish Stocks Agreement (UNFSA), the EU has a duty to cooperate directly with other parties, or through Regional Fisheries Management Organisations, to conserve and optimise the management of straddling and highly migratory fish. Article 5 UNFSA establishes that States must assess the impacts of fishing and environmental factors on the target fish species, and also on species belonging to the same ecosystem or food chain (UNFSA, 1995, Art 5). The aforementioned Regional Fisheries Management Organisations (RFMOs) are inter-governmental organisations that have competence under international law to adopt legally binding conservation and management measures. Importantly, the geographical area within which the RFMO can regulate must include part of the high seas (Asmundsson, 2016). Article 5 of UNFSA establishes the duty to adopt measures ensuring the long-term sustainability of straddling fishing stocks and highly migratory fish stocks. These organisations often establish catch limits or quotas, or Fisheries Restricted Areas (FRAs) or areas of Vulnerable Marine Ecosystems (VMEs). An FRA is a ‘geographically-defined area where specific fishing activities are temporarily banned or restricted’ to improve the fishing stock of the target species (GFCM/44/2021/5, Art 3). On the other hand, the establishment of a VME requires an assessment of the vulnerability of populations, communities and habitats based on factors such as uniqueness, rarity or functional significance of the habitat related to specific threats, precautionary conservation and management measures to prevent significant impacts on these ecosystems must be established (FAO, 2009, Articles 42 and 65). Since the EU is a member of several RFMOs, it has an obligation to incorporate decisions and conservation measures agreed within these organisations, with the consequence that they apply to all EU-flagged vessels (Altmayer, 2026).
European Union Law
Council Regulation No 734/2008 (2008) implements the international obligations mentioned in UNCLOS and the UN Fish Stocks Agreement, and it applies to all EU-flagged vessels, i.e. those that are registered in an EU Member State, operating bottom gears on the high seas in areas where no RFMOs exist or where no VME protection measures are in place. It also establishes the conditions necessary for these vessels to obtain the special fishing permit necessary for bottom trawling at the high seas (Council Regulation No 734, 2008, Art 4). This includes a detailed fishing plan and a prior, independent scientific impact assessment confirming that the activity will not cause significant adverse impacts, while fishing in unassessed areas is forbidden (Council Regulation No 734, 2008, Art 6). Furthermore, it requires both independent scientific observers on board all vessels, as well as satellite monitoring at all times, and departing from the approved plans, or failing the reporting requirements, is considered a serious infringement (Council Regulation No 734, 2008, Art 7). According to Articles 89 and 89a of Regulation No 1224/2009 (2009), it is up to national law to pinpoint the specific form that the sanctions must take in case of violation of the common fisheries policy, with the specific requirement that, whatever the form, the sanction must effectively deprive those responsible of the economic benefit that they obtained from the infringement. Regulation (EU) No 2016/2336 (2016) establishes specific conditions for fishing in the deep sea of the north-east Atlantic. It governs both EU and third-country vessels operating in EU waters, and it covers species that are characterised by “slow growth, late maturity, low natural mortality rates, intermittent recruitment of successful year classes and spawning that may not occur every year ”, found in deep-sea waters (Regulation (EU) No 2336, 2016, Art 3). The Regulation allows for bottom trawling with certain restrictions, including a complete ban on bottom trawling below 800 meters (Regulation (EU) No 2336, 2016, Art 8). There is also a Vulnerable Marine Ecosystem encounter threshold below 400 meters, whereby catching more than 30 kg of live coral, for example, triggers an immediate 5-nautical-mile move-on rule, as well as reporting duties back to the flag State about the encounter of a possible VME. Where VMEs are known or likely to occur, bottom trawling is completely prohibited (Regulation (EU) No 2334, 2016, Art 9). However, this leaves a large gap for the exploitation of shallow and continental shelf waters.
Regulatory and Enforcement Gaps
At first, it may seem that the EU is complying with all its international duties regarding deep-sea fishing. However, compliance with procedural requirements does not automatically demonstrate compliance with broader conservation obligations under UNCLOS. Bottom trawling not only destroys fragile benthic habitats, it also dredges up sedimentary carbon stores, which can release CO2 into the marine environment, causing further environmental harm (Atwood et al., 2024).
Under Council Regulation No 734/2008 (2008), the rules requiring special permits and environmental assessments, as well as independent observers, do not apply to high seas that fall under the responsibility of an existing Regional Fisheries Management Organisation. Under the RFMOs, protections vary widely across the high seas, since many of them implement environmental impact assessments and habitat protections unevenly: some have established zones banning bottom trawling entirely; others have only mandated that less-harmful trawling gear must be used to minimise the damage caused to the seabed (Barraclough, 2024). This highlights the fragmented nature of high seas governance and marine protection. It also ignores the interconnected nature of marine ecosystems, which do not always correspond to the boundaries of different RFMOs, especially in the case of highly migratory fish.
The institutional and legal fragmentation makes it extremely difficult to effectively manage the high seas. There are considerable differences between the RFMOs when it comes to their performance, the extent to which their operation and decision-making processes are transparent, and the procedures governing participation (Blasiak and Claudet, 2024). For example, an analysis of tuna RFMOs found that most of the progress was related to monitoring impacts on target species, with little progress on by-catch species or the monitoring of the food chain and habitats (Blasiak and Claudet, 2024). This type of management might help recover tuna populations to a healthy level, but it certainly does not account for the ecosystem-wide impacts of bottom trawling.
Conclusion
In conclusion, while the EU has established a legal framework regulating bottom trawling on the high seas, its effectiveness remains inhibited by fragmented international governance. The EU has complied with many regulatory requirements under both the UNCLOS and the UNFSA, but it has not achieved the conservation and cooperation obligations regarding living resources as established by Articles 117 to 119 of UNCLOS. Although the EU cannot be held solely responsible for these issues, it nevertheless has the capacity to exert political influence within RFMOs and advocate for more stringent conservation and management measures. Moreover, it could strengthen the regulatory framework governing matters falling within its exclusive competence, including the protection of marine biological resources (TFEU, 2016, Art 3(1)(d). This exclusive competence also includes the decision whether to be part of an RFMO, and thus abide by its standards.
References
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