Ⅰ. Introduction 
There has been a continuous growth in the global catch of major tuna species since 1975, and most tuna stocks are either close to full exploitation and some even in the status of over-exploitation. According to available statistics, catches by the world tuna longline fisheries accounts for some 14% of the global tuna production. They are caught by the world’s 1,454 large-scale tuna longline vessels. Among the fleet, Taiwan has a fleet of 614 vessels, or 42% of global large-scale tuna longline vessels. As an important user of global tuna resources, Taiwan has the responsibility of using the resources in a sustainable manner.

In 1999 Food and Agriculture Organization (FAO) of the United Nations adopted International Plan of Action for the Management of Fishing Capacity (IPOA-Fishing Capacity) calling upon States to reduce their large-scale tuna longline fleet by 20-30% to ensure the sustainability of marine resources. To meet with the objective of the IPOA-Fishing Capacity in achieving a global reduction of large-scale tuna longline fleet by 20%, Taiwan has implemented a 2-phase fleet size reduction program in 2005 and 2006 with the result of reducing the existing large-scale tuna longline fleet by 26%, in addition to strengthening of fisheries management.

II. Brief description of the 2-phase fleet size reduction program in 2005 and 2006 
In reduction of 160 vessels, of there are 59 vessels in 2005, and 101 vessels in 2006 respectively.

Ⅲ. Anticipating outcomes of the program 
Changes in the number of vessels after the completion of the reduction program in 2006 are shown in the above figure.

Ⅳ. The outcomes of Taiwan’s past measures on the management of fishing capacity
In addition to strengthening of fisheries management, Taiwan’s past measures on the conservation of marine resources include: restriction on the total number of vessels and the total tonnage in the fleet and the total number of large-scale fishing vessels, retention of the right of building of new vessels by the Government upon exportation of old ones. The policy of replacement of decommissioned vessels was first introduced in 1967, applying in the first stage to the restriction on the building new trawling vessels. Up to 2000, a total of 9 such policies were announced, with the exception of building of fish transport vessels of 2,000 tons or larger in 1991, and the policy of limited entry has been implemented in its entirety.
As from 1995, building of new vessel is not permitted after exportation of an old one. Therefore, the total number of motorized vessels and their total tonnage have been controlled at a suitable level and there will no further increase. Moreover, implementation of two-phase vessel buyback program respectively, from 1991 to 1995 and from 2000 to 2004, has reduced the total number of fishing vessels from 19, 000 to 15,000, with a reduction of approximately 20% of the entire fleet, and in term of vessel tonnage, a reduction from 968,000 tonnages to 830,000 tonnages or a 10% reduction. As for deep seas tuna longliners reduced from the two-phase vessel buyback program, the numbers are 136; that is, about 31,613 tonnages of the tuna longline vessels were reduced, and the reduction percentage is about 23%. The vessels bought back by the Government under the program were sunk to serve as artificial reefs for the purpose of contributing to the protection and conservation of marine resources in the coastal and offshore areas of Taiwan.

V. Conclusion
After the completion of the 2-phase fleet size reduction program in 2005 and 2006, it is expected that the total number of large-scale tuna longliners in Taiwan will be reduced from 614 to 454. This meets the objective of FAO IPOA-Fishing Capacity urging a 20% reduction of the world’s total large-scale tuna longliners. It is also in line with the international trend of enhancing fisheries management and conservation of marine resources for achieving the objectives of “assuming the responsibility of resources conservation” and “commensuration of the size of fishing fleet with the availability of fishing opportunities”.