Using Welfare Economics to Qssess the Farming Scale for Milkfish Chanos chanos Aquaculture in Taiwan

Abstract

This study conducted a series of simulations for reallocating the farming area of milkfish aquaculture based on a set of optimal prices according to the market concern. A supply and demand model was constructed using the multiple regression analysis, based on the data from 2004 to 2008 on the Annual Report of Fisheries Agency. Based on the producers' and consumers' surplus and social benefit, the optimal price was estimated to be 56 NTD/kg for an annual output of 42,398 MT. To reach the optimal price, the total milkfish farming area in Taiwan should be reduced for 20~34%, and 2,000 to 3,000 ha should be released for other types of farming. The reallocation plan was further evaluated for site selection. The evaluation on local temperature and productivity showed that the current farming area in Tainan is the optimal. This released farming area may improve resource utilization, thus increasing profitability and efficiency of aquaculture.本研究旨在平衡台灣虱目魚養殖供需，穩定市價，釋放低效能水土資源，以利整體產業效益。 研究應用2004至2008年漁業年報資料經複迴歸分析，建立虱目魚供需模型。藉由生產者剩餘、消費者剩餘與總體社會福利，估算出虱目魚在需求量42,398公噸時，其最適價格為56元／公斤。此時虱目魚養殖面積需減少20%至34%，可釋放2千至3千公頃做其他養殖。不論採用氣溫或是單位生產力做為釋放面積地點之選擇，皆指出台南為首要調整地區。若能適度釋放虱目魚養殖面積，改以放養高經濟魚種，將可有效利用水土資源，提升台灣養殖漁業整體經營績效。