MAXIMUM SUSTAINABLE YIELD

The highest theoretical equilibrium yield that can be continuously taken (on average) from a stock under existing (average) environmental conditions without affecting significantly the reproduction process. Also referred to as Potential yield . It is estimated from surplus production models (e.g. Schaefer model) and other methods. In practice, however, MSY, and the level of effort needed to reach it are difficult to assess. Referred to in UNCLOS, it is an essential fisheries management benchmark but it is also only one of the possible Management reference points, considered also as an international minimum standard for stock rebuilding strategies (i.e. stocks should be rebuilt to a level of biomass which could produce at least MSY). Sometimes confused with: Optimum yield. See : Long-term potential yield (LPTY)