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both criticized and extended these basic models. In spite of these

extensions, the basic conclusions of Gordon's model have been maintained

in nearly all bioeconomic models. These conclusions are that the common

property nature of the resource creates a situation in which the open

access equilibrium in the fishery generates socially undesirable levels

of catch and effort and that some type of restrictions on the fishery

are necessary as a means of correction. Commensurate with this is

Gordon's creation of the management goal of attaining maximum economic

yield rather than the more traditional goal of maximum sustainable

yield generally proposed by the biological discipline.


Dynamic Bioeconomic Fishery Models


 One of the first criticisms of the traditional model was made by

Scott (1955) and later extended by others, most notably Clark (1976).

This criticism was aimed at the concept of the static MEY. More pre-

cisely, it was argued that since catch was a function of population and

population was a function of catch, a dynamic concept of MEY was needed.

To attack this problem, Scott developed the concept of user cost.4

Basically, Scott argues that the feedback relationship between catch and

population size implies that "correct" regulation of a fishery requires

an examination of the discounted present value of returns in the

fishery. Thus, any increase in marginal current revenue (catch) must be

weighed against the cost of such an increase in terms of diminished

present value. Scott defines user cost to be the "effect of succeeding


 4Scott's argument was couched in terms of the sufficiency of sole
 ownership of the fishery with the attainment of MEY. The essence of his
 argument, however, involves the optimality of static versus dynamic MEY.