Optimal Fishing Effort in the Peruvian Anchoveta Fishery 



Edilberto L. Segura' 



ABSTRACT 



This paper introduces a new approach to measuring technical change, increased 

 skills of the skipper and the fishermen, water temperature, etc., to obtain a better measure 

 of fishing effort and therefore a revised estimate of the optimum quantity to be landed. 

 The revised technique used adjusts the level of landings to an index rather than the 

 level of fishing effort, indicating the level of landings that would have resulted in 

 previous periods if the current landings/effort relationship is used. 



The revised yield/effort relationship which results yields 16.2 million ton-trips as 

 the optimal fishing effort, as opposed to the 23 million ton-trips which were obtained 

 without this measure of technical change. 



INTRODUCTION 



During the last decade the Peruvian fishing 

 industry has become one of the most important 

 elements of the Peruvian economy. In 1969 

 Peruvian exports offish meal and fish oil reached 

 U. S. $195 million, or 30% of total Peruvian 

 foreign exchange earnings during that year. 

 Almost all fish meal and fish oil production has 

 utilized "anchoveta" (E)igraulis ri)ige)is) as raw 

 material. Total landings of anchoveta have 

 increased from 1.9 million metric tons in 1959 to 

 8.9 million metric tons in 1969. This increase in 

 landings represents an average annual rate of 

 growth of 18% . 



In recent years, due to the rapid expansion 

 of the industry, its importance to the Peruvian 

 economy, and the size of the landings, several 

 studies have been made to determine the maxi- 

 mum sustainable yield of the Peruvian fish 

 stock and the optimal level of fishing effort 

 (Boerema et al., 1965; Schaefer, 1967, 1970; 

 Gulland, 1968). Although these studies contain 

 extensive discussions of fishing effort, there 

 remain some doubts about the adequacy of the 

 measures used to evaluate fishing effort. As a 

 result, the estimation of the optimal level of 

 fishing effort has been biased. In this paper I 

 attempt to estimate the optimal level of fishing 

 effort taking into consideration the effect of 

 input variables not previously included, such as 



technological change, increased skills of skippers 

 and fishermen, water temperature, etc. 



CONCEPTUAL ISSUES 



In a bioeconomic model, fishing effort is an 

 index or proxy for several inputs that partici- 

 pate in the fishery, including capital, labor, 

 management, technological change, and other 

 variables. Although the fishing effort index 

 might vary for different fisheries, it can be 

 generalized as being the product of fishing time 

 (number of days in grounds, number of trips 

 made, number of hours fished, etc.) multiplied 

 by some measure of fishing power (gross tonnage, 

 length, engine horsepower, etc.). This measure 

 should be a proxy for capital and labor. The 

 resulting measure of fishing effort should be 

 corrected by such factors as technological 

 change (introduction of power block, echo 

 sounder, steel vessels, etc.), changes in manageri- 

 al and fisherman skill, and other variables that 

 represent changes in fishing power. To determine 

 the optimal fishing effort in the fishery and the 

 maximum sustainable yield, most of the studies 

 of the Peruvian stock have utilized the following 

 Schaefer production function: 



' Ph.D. Candidate, Columbia University and Economist 

 of Bailey, Tondu, Warwick and Company, Ltd., New York. 



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