Huang Hui, Leung PingSun
University of Hawaii at Manoa, 1955 East-West Road #218, Honolulu, HI 96822, USA.
J Environ Manage. 2007 Sep;84(4):523-33. doi: 10.1016/j.jenvman.2006.07.008. Epub 2006 Sep 27.
Interactions with sea turtles have occurred at an alarming rate in swordfish longlining in Hawaii in recent years and various regulations have been put forward to protect sea turtles. In order to understand the cost of reducing sea turtle interactions, methods have been developed to derive the shadow price of sea turtle bycatch based on fisher's welfare loss from a specific regulation. This paper illustrates an alternative method of calculating temporal and trip-specific cost of sea turtle bycatch reduction. The advantages of this method lie in the computation of shadow price without assuming specific regulation implementation and its relatively modest data requirement. A parametric output distance function is used to simultaneously model desirable and undesirable catches. Using the duality argument, the revenue-related shadow price of sea turtle bycatch can be derived from the estimated distance function. Average shadow price of sea turtle bycatch for the period 1991-1999 is estimated to be US $30873 in 1991 dollars. Average shadow prices of sea turtle bycatch by trip characteristics, such as fishing year, trip type and location are also estimated. Such information can be useful for policy makers to analyze tradeoffs and make appropriate policy decisions.
近年来，在夏威夷旗鱼延绳钓作业中，与海龟的相互作用发生率令人担忧，为此已出台了各种法规来保护海龟。为了了解减少海龟相互作用的成本，已开发出一些方法，根据特定法规导致渔民福利损失来推算海龟兼捕的影子价格。本文阐述了一种计算减少海龟兼捕的时间成本和每次捕捞成本的替代方法。该方法的优点在于，在不假设具体法规实施情况的前提下计算影子价格，且数据要求相对适中。使用参数化产出距离函数同时对期望渔获量和非期望渔获量进行建模。利用对偶性原理，可从估计的距离函数中推导出与收益相关的海龟兼捕影子价格。1991 - 1999年期间，海龟兼捕的平均影子价格按1991年美元计算估计为30873美元。还估算了按捕捞年份、捕捞类型和地点等捕捞特征划分的每次捕捞海龟兼捕的平均影子价格。此类信息有助于政策制定者分析权衡利弊并做出适当的政策决策。
