Catch Equation Constraints


 The above discussions concerning the total revenue and total cost

components of the reef fishery profit function serve to define the basic

economic relations necessary to derive MEY. To complete the model,

technical constraints in the form of the estimated state catch equations

are necessary.

 The estimated state catch equations were discussed in detail in

proceeding sections where it was shown that the estimated catch equa-

tions could be manipulated algebraically to obtain derived equilibrium

catch equations. This is the form in which the catch equations are

entered as constraints on the model. The use of the equilibrium form

of the catch equations implies that the model solutions are long run

equilibrium solutions resulting from the adjustment of the resource

stock.

 Fishing power in the catch equations is taken to be exogenous.

Thus, the catch constraints in the optimization model express catch in

each state as a function of the number of vessels fishing in that state

with a predetermined level of average fishing power per vessel. This

exogenous treatment of fishing power in the model forces the MEY solu-

tion obtained to be a conditional optimum. The optimum is conditional

in the sense that no economic efficiency criteria such as marginal

conditions on the fishing power components are considered. Failure to

consider such criteria is not unreasonable, however. The measures which

define crew size and vessel size are aggregate averages corresponding to

vessels in each state. Within the catch equations these factors serve

to measure the aggregate average input composition of vessels in