ABSTRACT
This chapter focuses on relatively simple population models but also begins to prepare the way towards understanding some of the requirements of more complex models. Such static models contrast with what authors call dynamics models, which attempt to describe processes such as changes in population size, where the value being estimated at one time is a function of the population size at an earlier time. Ignoring any potential immigration and emigration, stock production is a combination of the recruitment of new individuals to a population and the growth of the individuals already in the population. Growth rates can be complex processes affected by the length or age of each animal, but also by the environmental conditions. The growth curve described by the Fabens transformation of the von Bertalanffy equation uses the same parameters but has smuggled in differences that are not immediately obvious.
