A poor catch and hard maintenance work were noted for the first year (2003) that the set-net was in operation due to an inappropriate design of the gear and lack of familiarity with the gear by the fishers, resulting in a low number of operation days and a low value of unit price. After technical advice and support from the Japan-side counterparts in 2004, the gear design was improved in three major aspects, namely, net width in the main net system was decreased, the setting of the slope net from the playground to the chamber trap was lowered and narrowed, and 800 sandbags, each 60 kg were used to replace the iron anchors originally employed for gear installation in 2003.
The routine work of net maintenance, such as the periodical net cleaning and replacement with spare nets, was also improved: every 3 weeks for the chamber trap, 2 months for the playground, and 3 months for the leader net.
The operation time for the hauling process originally required 40-60 min with three to four Thai traditional boats (6.0 m LOA, 60 HP). The hauling process was improved and made easier in 2006 when a fiber-reinforced plastic (FRP) boat (10.9 m LOA, 30 HP) equipped with an engine-driven line-hauler became available. The hauling operation with the larger FRP boat together with two local boats just requires 20 min, so completion of all daily activities, including fish sales from the beach fish shop, takes about 2-3 h. This large FRP boat also provided the technical support for the gear installation and maintenance tasks carried out only by the fishers' group. Another improvement effort in terms of gear design was the resetting of the bottom fixing ropes at the chamber corners in 2005, which ensured that chamber shape would be maintained even with the strong current in the fishing ground. The portable engine for driving the high-pressure water jet and the capstan winch with the bow net roller was also installed onboard the FRP boat, which contributed to make the daily fishing operation and maintenance activities more convenient and time/labor efficient, although the use of these auxiliary devices resulted in higher fuel consumption, thereby increasing the daily operation costs.