Resources of squids became less and less, thus lead to the decrease of squid production. Currently, the most researches of squids focused on the relationship between catches of torch-light fishery and fishing environments, as well as biological study of squids which caught by torch-light fishery. Trawl fishery is also one of the main fisheries that caughtes squids. The results showed the distribution range of mantle length in trawl fishery (1.8~40.82cm) was wider than the range of torch-light fishery (2.1~32.9cm). The sex ratio showed the squids caught by torch-light fishery had more males with significant sex difference. The monthly variation of GSI showed that both area of the male squids had a peak value in spring and autumn. In addition, the results of mantle length at 50% sexual maturity excluding spring showed the squids caught in trawl fishery were bigger than torch-light fishery. Exponential and power growth models explained the fit to the size-at-age data to a similar extent.
Alternatively, to observe the he sword tip squid sample in the northeastern water of long-term changes. And the year of average mantle length almost 90mm are not change more in 2001 to 2012. The average of weight is clearly go down in 2001 to 2007. But, In 2008 get high and in 2009 to 2011 also decline. In terms of the abundance index ,it begin period joined by 2002 to 2006 and part of year in which it is added.
The activity of squid half of 2012. To catch the fisheries of squid include trawl fishery, gillnet fishery, torched-light net fisheries, danish seine net fishery, porgy and miscellanous fish long line, pole and lines boote, and troll line fisheries.It has 236 sample vessels totally. Among the catch of squid, the trawl fishery catch 251ton and torched-light net fisheries catch 224ton. The CPUE of vessels concentrate in northeastern, west and Penghu waters.Then the distribution of northeastern water is the most widely. The distribute of torched-light net fisheries’s operation is extending from south of 26°N to west waters ,and distributed all the western waters. And the operate of pole and lines boote is mainly in the waters off Penghu. The catches and effort’s distribute is similar in offshore and coastal fisheries. However the CPUE’s waters of trawl efficiency is highest from part of south 25°N to Yun-Chang Rise.
The fishing lamps of offshore and coastal fisheries is used overview then the useful part is in northeastern of Taiwan ( mean lamp 44). And the used of ton class emerges of exponential increase, CT0 to CT6’s average lamp are total in 10.4 - 98.1
Keywords: squids, waters off northeastern Taiwan, trawl fishery, t orched-light net fisheries,