Fishing Power


 The estimated catch equations represent reduced form expressions.

It can be recalled from equation (44) that total effort was composed of

nominal effort and fishing power, and that the estimated fishing power

function can be derived from the estimated reduced form catch equations.

The estimated fishing power function corresponding to equation (43) for

an arbitrary state in the GMRFF is given by


 .9635 .4601 (75)
 Pi li 2i


where Xli and X21 are average crew size and average vessel size in the

ith state, respectively.2 Examination of equation (75) indicates that

average crew size has a much larger effect on fishing power than does

average vessel size. This was expected, however, as crew size is a

direct measure of "gear contact" with the resource stock. The estimated

fishing power elasticity corresponding to crew size is 0.9635, implying

a 10 percent increase in average crew size would increase fishing power

approximately 9.6 percent. The corresponding elasticity for average

vessel size is estimated to be 0.4601. Thus, a 10 percent increase in

average vessel size increases fishing power 4.6 percent. To the extent

that vessel size measures the ability of vessels to undertake and

sustain the fishing process, this elasticity may be interpreted as the

effect on fishing power of increased fishing time. This interpretation


 It will be recalled that the fishing power function's constant
term was subsumed in the intercept of the catch function. In that the
ensuing discussion proceeds in relative terms, the constant in equation
(75) has been set equal to one with no loss of generality.