Simple methods for short-term forecasting of catch and biomass

Abstract

A simple method for making short-term forecasts of catch and exploited biomass, based on a time-dependent stock-production model, is described. The method can be applied in various ways, depending on the nature of the data available. A short time series of landings estimates is required, and a reliable indicator of recruitment is highly desirable. The level of exploitation must also be estimated, but results are not usually very sensitive to this parameter. Given a good index of recruitment, the method is capable of giving satisfactorily precise catch forecasts even when the level of exploitation is high and recruitment is quite variable. The method can easily be implemented as a spreadsheet, and several examples are presented.