EDITORIAL

Effective and sustainable management of inshore fisheries resources is a goal of many countries. It is now apparent, however, that such aspirations cannot always be met nationally. The paper by Ablan et al. in this issue entitled “Meso-Scale Transboundary Units for Management of Coral Reefs in the South China Sea ” makes this point well. Even for relatively site attached coral reef fish, their data show genetic affinities among individuals at scales that transcend national boundaries. The implications are clear: nations must be prepared to co-operate to manage coastal fisheries resources. The alternative is that good management practice by one country may be undone by a neighbor. The importance of reliable information on the genetic structure of stocks should not be under-estimated. Different population units can have varying rates of growth and reproduction, and there is often limited scope for an overfished population unit to be replenished from an adjacent one. Unless we know what we are managing, efforts to involve communities in decision making, develop access rights, reduce catch to restore spawning biomass, etc. may miss the mark. In particular, if we do not know the area used by a ‘stock ’ (population unit) we cannot reliably identify the stakeholders and invite them to the table to develop co-operative management measures. In tropical multi-species fisheries, the task of identifying the number and extent of discrete populations units for each species is daunting. But is there any alternative? Ablan et al. considered whether the Large Marine Ecosystem units identified for Asia may simplify the process, but then go on to show that the South China Sea LME may need to be subdivided into at least four management units for coral reef fishes. They also point out that the spatial distribution of their sampling was not fine enough to determine whether these four area