| 英文摘要 |
Torch light net fishery is one of the considerable scale fisheries in coastal and offshore waters of Taiwan. Because of Taiwan is located in the subtropical zone, and the water masses and marine environmental conditions around the Taiwan are not similar, so the sea areas where the structure of torch light net fisheries have similarities and differences each other, but it has been lacking relevant comparative research all the time. Therefore, this study collect the fishing activity data (including fishing composition, catches amount, fishing position, fishing depth and fishing gear etc.) from sampling boats of torch light net fisheries in northeastern, southwestern and Peng-hu waters of Taiwan, and match up the sea surface image of remote sensing data to confer the fisheries structure of torch light net fisheries in these three areas. In addition, analysis the fishing lights of torch light net fishing boats simultaneously, and evaluate the using of fishing light intensity.
The results of comparative studies show the fishing method in northeastern area is stick-held dip net, the fishing seasons are April to November, the fishing ground is located at 25~28°N,121~126°E on the east China sea continental shelf catching 9 families 15 species, the target species are skipjack, squid and triggerfish etc., the average CPUE is fluctuated between 40.29~1,821.41 kg/boat-day, the evenness index is between 0.86~0.99, and the diversity index is between 0.46~0.93. The fishing method in southwestern area is danish seine which operate all the year, the fishing ground is located at 21~23?N, 118~120?E between the Peng-hu channel and the Taiwan bank catching 15 families 29 species, the target species are skipjack, moonfish, mackerel and scad etc., the average CPUE is fluctuated between 1191.53~3829.56 kg/boat-day, the evenness index is between 0.94~1, and the diversity index is between 0.3~1.37. The fishing methods in Peng-hu area are stick held dip net and danish seine in accordance with different target species which fishing season is May to October, the fishing ground is located at 22~24?N,118~120?E near the Taiwan bank catching 11 families 23 species, the target species are herring, sprat and squid etc., the average CPUE is fluctuated between 52.56~848.69 kg/boat-day, the evenness index is between 0.91~1, and the diversity index is between 0.3~1.11.
The results conclude the structures of torch light net fisheries in coastal and offshore waters of Taiwan are not similar, it revealed that the structures of the northeastern and Peng-hu area are more similar. Therefore, if want to draw up the management measures of torch light net fisheries in the future, it should be concerned the difference of area that might be more appropriate. |
