The Oceanic Northeast Atlantic ecoregion consists of the portion of the
ICES Area that is beyond national jurisdiction (ABNJ), i.e. outside the 200 mile
limit of the exclusive economic zones (EEZs) of the EU Member States, the Faroe
The ecoregion is mostly deeper than 1000 m, with only a
small fraction of the seabed (ca. 0.03%) shallower than 500 m. The area
comprises mostly extensive abyssal plains, with the Mid-Atlantic Ridge (MAR),
many seamounts, and the Rockall–Hatton Plateau rising above the abyssal plain (Figure 1).
This ecoregion is entirely oceanic, and differs from all other ecoregions by
being distant from land; as a consequence, it is much less influenced by
coastal and terrestrial processes. A number of claims
are made on the parts of the continental shelf that extend into the ecoregion
from adjacent EEZs. Alongside the exploitation rights, such claims carry
responsibility to protect the seabed and its habitats.
Regulation of the fisheries
The Northeast Atlantic Fisheries Commission (NEAFC) is the regional fisheries management organization mandated to manage most fisheries in the Oceanic Northeast Atlantic ecoregion. These include fisheries for pelagic stocks of mackerel (Scomber scombrus), herring (Clupea harengus), blue whiting (Micromesistius poutassou), and redfish (Sebastes mentella), as well as demersal fisheries for haddock (Melanogrammus aeglefinus) and deep-sea species. These fisheries are conducted both inside EEZs and in the ABNJ, where they are regulated by a mixture of national, EU, and NEAFC measures. NEAFC has frozen the fishing footprint by designating existing fishing areas within which bottom fishing is permitted. Outside these areas bottom fishing is prohibited, and any new fishery wanting to be developed must do so under an exploratory fishing protocol. In addition, extensive areas within the fishing areas have been closed to protect vulnerable marine ecosystems (VMEs). NEAFC has banned targeted fisheries on deep-sea elasmobranchs. Individual parties to NEAFC have implemented additional measures for their own fleets fishing in international waters, e.g. the recent changes in EU fishing opportunities for deep-sea species. NEAFC measures are legally binding, and activity by contracting parties or third parties not complying with the measures is regarded as illegal and may lead to sanctions, such as the blacklisting of vessels. All fishing vessels in the NEAFC area are monitored by electronic vessel monitoring systems (VMS). NEAFC receives scientific advice on stocks and ecosystem components from ICES. The Long Distance Fleet Advisory Council (LDAC) also provides advice via the European Commission.
The International Commission for the Conservation of Atlantic Tunas (ICCAT) is the regulatory authority for the fisheries of tuna and other large pelagic species. The North Atlantic Salmon Conservation Organization is the regulatory authority for the distant-water salmon fisheries, such as those off Greenland and Faroes, as these are largely confined to EEZs rather than to the ABNJ.
Regulation of other human activities
The International Whaling Commission (IWC) and national authorities regulate the harvesting of whales. None are harvested from the ecoregion at present. Advice to some nations is provided by the North Atlantic Marine Mammal Commission (NAMMCO). The International Seabed Authority (ISA) is the regulatory authority for mineral extraction (mining). There is, as yet, no mineral exploration or extraction activity in the area. The International Maritime Organization (IMO) is the regulatory authority for shipping; this is extensive across the area, especially in the southern part of the ecoregion.
The OSPAR Commission is the regional environmental management organization that promotes protection and conservation in the Northeast Atlantic. Though OSPAR has a limited regulatory mandate in the high seas, it has introduced seven high-seas marine protected areas (MPAs) since 2010. Some of these, but not all, overlap spatially with areas closed to fisheries by NEAFC to protect VMEs. OSPAR maintains a list of “threatened and declining species and habitats". OSPAR's actions serve to raise awareness on needs for management actions by national authorities and organizations with the appropriate mandates. OSPAR and NEAFC collaborate and promote common processes, in relation to the other organizations mentioned above and relevant international mechanisms such as the Convention on Biodiversity (CBD). States with extended continental shelf claims within the ecoregion are also obliged to implement conservation measures if appropriate.
Figure 2: OSPAR marine protected areas within the ICES Oceanic Northeast Atlantic ecoregion (Source: OSPAR MPA Map Tool; http://carto.mpa.ospar.org/1/ospar.map)
The oceanography of the ecoregion is dominated by the Subtropical and Subpolar Gyres. These systems are bounded by the Subpolar Front (SPF), which divides the ecoregion into a relatively cold area to the northwest and a relatively warm area in the south. The Subpolar Gyre carries cold, low-salinity, and highly oxygenated intermediate Labrador Sea Water to the ecoregion. The northern branch of the Subtropical Gyre (the North Atlantic Current, NAC) transports warm waters to the northeastern part of the region (Figure 3). Both gyres are integral components of the Atlantic Meridional Overturning Circulation (AMOC), a large-scale ocean circulation process that also has profound consequences for atmospheric climate. The Subpolar and Subtropical gyres have profound influence on the processes underlying the distribution and productivity of biota, and the exchange between neighbouring ecoregions.
Figure 3: Sea surface temperatures and diagrammatic representation of the main currents in the North Atlantic. Where cold and warm currents co-occur, warm water overlays cold water (ICES Report on Ocean Climate (IROC) 2017 – Gonzalez‑Pola et al., 2018).
Figure 1: ICES Oceanic Northeast Atlantic ecoregion, corresponding to the area beyond national jurisdiction (ABNJ) in the eastern North Atlantic.