Introduction
Assessment and management of fish stocks1 has had a long history, with many successes and failures. Failure to manage a fishery appropriately can have disastrous effects on social
1 Stock is here defined as the proportion of a population consid- ered to be a unit for fisheries management. This may be all or part of the population, and may be defined on the basis of spatial distri- bution or other characteristics. The definition of a stock may change over time as a fishery expands into new areas. However, for our purposes, we assume that the definition of a stock does not change over time.