Environmental and Economic Assessment of Fee-Fishing in Sao Paulo State, Brazil

摘要

According to feed producers, aquaculture in Brazil generates an annual income of about US 200 dollar million and is growing at an annual rate of 15%. More than 300,000 people are involved, including fish and shrimp farmers, feed companies, technicians and equipment manufacturers. The growth of the aquaculture industry has given rise to concerns about such environmental issues as water pollution and the conversion of land to ponds. "Fee-fishing" is the maintenance of ponds so that people can fish from them, primarily by line, usually for an entrance fee and for a fee paid per kilogram of fish caught. Attendant activities on the farm site, such as restaurants and ecorural tourism, also generate considerable revenues. Fee-fishing started on marginal areas unsuitable for agriculture or other activities, but it has recently expanded rapidly to occupy former farmland and areas of land close to the large urban centers. Fee-fishing either supplements the income or is the main source of income for many people. It generates 60 dollar million (U.S.) per year at the Piracicaba River watershed in Sao Paulo State alone. The annual average net income of the fee-fishing farms studied equals 46% of the total costs, with variations from 8% to 120% over the totalcosts per year. In 22% of the fee-fishing areas, the pH and dissolved oxygen are controlled, and in the worst cases (almost 6% of the sites sampled), none of the physical and chemical parameters of water quality are controlled. The fee-fishing farms evaluated in this study usually have low-quality water. Only 6% of the fee-fishing farms have some sort of effluent treatment system. Fee-fishing farms should improve management to enhance their attractiveness to tourists and to prevent negative environmental impacts.