Our research is about marine protection. MPA networks that include representative coverage of all environment types and the ecosystems and species that they contain are fundamental for effective biodiversity conservation. Establishing MPA networks to address issues of conservation and sustainable use of biodiversity in international waters is a priority recognised by the new Biodiversity Beyond National Jurisdiction (BBNJ) Agreement, which provides the legal mechanism to protect the high seas. The contribution of representative protection from sectoral and regional management authorities for the high seas is critical to the success of the BBNJ Agreement and for meeting larger protected area targets such as the pledge under the Kunming-Montreal Global Biodiversity Framework (GBF) to protect at least 30 per cent of land and sea by 2030.
In our research, we quantified the benefits and risks associated with different planning scenarios for the design and implementation of large-scale marine protected area networks, such as those needed for the high seas. In the Southern Ocean, the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), has committed to develop a representative system of Southern Ocean Marine Protected Areas (MPAs) for the CCAMLR Area. Investment in planning and implementation over the past decade has resulted in the declaration of two large MPAs - the Ross Sea region MPA and the South Orkney Islands Southern Shelf MPA - and the ongoing development of a larger representative system is underway.
To date, MPAs have been established and proposed incrementally in different planning domains using a bioregional planning approach, whereby the CAMLR Convention Area is divided into nine MPA planning domains, based on the location of Southern Ocean bioregions. Theoretically, conservation planning in each bioregion will result in MPAs that protect ecosystems and species within the region, and collectively across all bioregions the MPA system will therefore be representative of all ecosystems, environment types, and species that they contain. For example, key conservation features in need of protection include coastal bays that provide critically important feeding areas for species that live on and around the fast ice, such as penguins and seals (Figure 1).
However, an incremental planning and implementation process is likely to miss key protection targets for conservation features and thus the MPA system may not be truly representative.
We tested the suitability of a bioregional planning approach to deliver a representative network of MPAs for the Southern Ocean, using a Systematic Conservation Planning (SCP) framework and four planning scenarios that represent ongoing stages of the current incremental CCAMLR MPA planning process. Results from each scenario showed the extent to which meeting conservation targets at a circumpolar scale was feasible, and the next key places that need protection.
Importantly we found that current and proposed MPAs protect many conservation features. However, under the current planning scenario where MPAs are established incrementally in different planning domains, some conservation features will remain underrepresented and very large MPAs in yet to be planned for domains will be required to achieve representative protection. In many cases an extension of boundaries of existing and proposed MPAs would increase representation. As such, for the current planning approach to deliver a representative Southern Ocean MPA system, political will is required to adapt existing and proposed MPAs at ongoing stages of the incremental planning process.
While our results and recommendations are specific to CCAMLR and MPAs in the Southern Ocean, they have implications for MPA planning in Areas Beyond National Jurisdiction (ABNJ) more broadly. Where multiple countries are involved in a marine space, such as in CCAMLR, other ABNJ, or when planning across multiple maritime zones and jurisdictions, bioregional planning can help regional planning processes to incorporate broader network representation targets in regional plans, by incorporating adaptive designs as the network comes together incrementally.