There is overwhelming evidence from around the world that without catch regulation and conservation measures no marine fishery is sustainable. Since 1984 the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) has been regulating catches throughout the Southern Ocean, but acceptance of marine protected areas as key conservation measures has proved more difficult to achieve. A major step forward happened in November 2011, when Members agreed a Conservation Measure setting out a general framework for the establishment of marine protected areas (MPAs) in the CCAMLR Area. CCAMLR Members and Antarctic Treaty Parties have previously committed to work towards the development of a representative system of MPAs in the Southern Ocean by 2012 and some progress has been made here with the designation of the South Orkney Islands Southern Shelf MPA in 2009 and the ongoing development of new proposals, for example in Eastern Antarctica and the Ross Sea. But, to meet this objective, there is an urgent need for CCAMLR to return to its fundamental principles of a precautionary approach to the conservation of marine living resources.

The new Conservation Measure (CM 91-04) states that MPAs “shall be established on the basis of the best available scientific evidence”. Despite the relative paucity of marine scientific data in some parts of the Southern Ocean, approaches are now being developed to allow for precautionary decisions to be made on the basis of this available evidence, to meet the objectives for protection as set out by the Measure. However, some recent proposals appear to have been judged purely on whether the data are sufficient, rather than on whether they are the best available. If this judgement forms the basis for objections to an MPA proposal, then the precautionary approach is overturned and there is little opportunity for critical evaluation of the data which do exist. The question of ‘how much data is enough?’ is likely to have a different answer for every MPA proposal, depending on the characteristics, level of threat and feasibility of studying any particular area. Focusing on this question is a misinterpretation of the meaning of “best available scientific evidence” in the context of MPA planning, and it risks undermining the ability of CCAMLR to make progress on establishing further MPAs where they are most needed.

New scientific research is always desirable to underpin our understanding of a new MPA, but may be currently impractical because of access, financial constraints, timing, or the sheer size of the area to be surveyed. Similarly, the requirement in CM 91-04 for research and monitoring plans as part of new MPA proposals is important in assessing the degree to which the objectives of an MPA are being met. However, neither the development of such plans nor an obligation to carry out expensive or impractical research should be allowed to delay the establishment of protected areas. In contrast to most, if not all, other high seas areas of the world, the Southern Ocean is unique in having well-established legal and procedural mechanisms in place for the designation of protected areas, now strengthened further by CCAMLR's agreement of a Conservation Measure on MPAs. The 2012 target is unlikely to be met in full, but CCAMLR has the opportunity to make significant progress this year by strengthening its commitment to a precautionary approach. The challenge now is for CCAMLR to build on its success in establishing the world's first entirely high seas MPA, and to take on a role of global leadership by establishing the world's first representative system of MPAs for an entire ocean ecosystem.