ABSTRACT
This chapter attempts to get to the core of some of the stock assessment methods to describe their foundations and some aspects of their application. Many such individuals who will work on developing country fisheries graduate annually from universities in Europe, the US and in some developing countries. The catch curve analysis makes some strong assumptions as to the population equilibrium and constancy of the biological parameters. The early work on catch curve analysis assumed the ability to estimate the ages of the sampled animals, which would usually be ascertained with the help of an age-length key. The most well known yield, age-structure-dependent model is probably that of Beverton-Holt, in which age enters via the von Bertalanffy model parameters. D.A. Fournier and I.J. Doonan contributed a delay-difference model designed to estimate the parameters of exploitation. The model is quite general, incorporating multiple improvements over its closest analogy of 7 years earlier, which is found in the age-dependent literature.
