Some Definitions of Overfishing Relevant to Coastal Zone Management in Southeast Asia

~ oastal zone management (CZM), ~ a multidisciplinary activity par excellence. involves branches of the natural and social sciences in which the concept of overfishing has no operational meaning. Thus, fishery biologists working alongside representatives of other disciplines are often hard-pressed to define this concept, which is of crucial importance to fishery management. This essay is an attempt to define overfishing in terms less technical than those generally used by fishery biologists. I staned from the classical definition, then quickly moved on to what I hope are concepts that may be more relevant to CZM. Overfishing is a single process, but may be viewed as having five facets, of which three are recognized forms of overfishing. The first well-known form is growth overfishing, which what happens when fish are caught before they have time to grow. This form, which began to occur in some Nonhero European fishing grounds as early as the end of the last century has been solved in theory by the Russian scientist F.I. Baranov just after World War I. However, it is the work of RJ.H. Beverton and SJ. Holt (of the Lowestoft Laboratory, Britain) which after World War II presented methods by which growth overfishing could be diagnosed in practice and remedied by fishery management (for example, through the imposition of appropriate mesh sizes for fishing gears). Research work related to overfishing nowadays conducted in various research institutions throughout the world (including ICLARM) consists of estimating the ages, and the growth and mortality rates of fish and assessing the (mesh) selection characteristics of fishing gears, as well as adapting Beverton and Holt's and related models to the multispecies situation typical, e.g., Southeast Asian coastal trawl fisheries. The second recognized form of overfishing is recruitment overjishing which