The designation of BIOT as a marine reserve in 2010 sets a precedent for marine conservation in the Indian Ocean. International marine conservation organisations have a strong voice in the region and campaigns to protect large areas of ocean within marine reserves gain momentum. In the late 2010s, with existing fishing fleets beginning to overexploit stocks, a number of East African coastal states opt to close their EEZs to industrial tuna fisheries rather than to develop their own national offshore fleets. This decision is motivated not only by the deterioration of tuna stocks, but also because the protection of very large areas of ocean serves as a big leap forward in achieving international biodiversity conservation targets for protected areas. The closure of national EEZs to industrial fishing necessarily involves withdrawal from EU fisheries partnership agreements or privately negotiated access arrangements, although in most cases the opportunity costs associated with prohibiting fishing access are offset using alternative financing mechanisms. In the early 2020s, with existing management measures largely failing and stocks of yellowfin and bigeye in a chronically depleted state, pressure mounts within IOTC for the implementation of a robust policy of spatial management. These proposals are seen as over-precautionary by some members and initial negotiations stagnate. However, coordinated awareness campaigns run by environmental organisations in Europe and Asia help to steer political opinion, and by the mid 2020s consensus is reached within the IOTC to close a large area of the high seas to the industrial fleets. This single area closure is situated in the northwest Indian Ocean and excludes fishing from a highly productive region associated mainly with fishing on FADs