A bio-economic analysis of the hand-line and gillnet coastal fisheries of Pernambuco State, north-eastern Brazil

Abstract

This paper presents a bio-economic analysis of the hand-line and gillnet coastal fisheries off Pernambuco State, north-eastern Brazil, in order to define management measures to support the decision-making process available to fisheries managers to reduce uncertainties about the sustainable development of the fisheries. The objective of applying a bio-economic model was to reproduce the biological and economic conditions in which the fisheries occur. This was done by carrying out projections and simulations, starting from the current situation and going forward into the future with the purpose of analysing the behaviour of the fishery under different conditions, particularly different management measures. Six scenarios are presented, defined by different management regimes: Scenario 1: increase in catchability; Scenario 2: reduction in fuel price; Scenario 3: closed season; Scenario 4: reduction in the number of active boats; Scenario 5: reduction of catches of juveniles; and Scenario 6: joint implementation of biological, economic and technical management strategies. Management events were always introduced in the fifth year of the simulation, with the exception of Scenario 1, in which the event was introduced in the first year. For each of the five scenarios, a deterministic simulation was carried out with a Beverton-Holt model of the stock-recruitment relationship. Simulations were carried forward through a 30-year period. The best management strategy, in biological and economic terms, seems to be the joint application of several management measures that satisfy the claims of stakeholders, and permit a biological and economic equilibrium between the activity and the efforts to rebuild stocks.