Fish Population Dynamic and Stock Assessment

7.1.2. Yield / recruit model of Beverton and Holt

            The Beverton–Holt model is a classic discrete-time population model which gives the expected number n_t+1 (or density) of individuals in generation t + 1 as a function of the number of individuals in the previous generation.

The yield / recruit model of Beverton and Holt is also called as analytical model.  This model is in a principle a “Steady state model”.  This means that the model describes the state of stock and the yield in a situation when the fishing pattern has been the same for such a long time that all fish alive have been exposed to it since they recruited. (Sparre and Venema, 1998).

Using a right mesh size, yield is optimized from a given number of recruits. According to Gulland (1983), calculation of yield from a given recruitment, known as yield per recruit, is a basic element in the assessment of fish stocks.