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为评估长江口鳗苗网对兼捕鱼类的危害性,2011年3-4月,在长江口8个鳗苗网设置点采集96网次,采获兼捕鱼类3 755尾,隶属16科,35种。其中海洋性鱼类12种,河口性鱼类14种,洄游性鱼类3种,淡水性鱼类6种。兼捕鱼类的发育阶段为稚鱼和幼鱼。其中刀鲚(Coilia nasus)为最优势种,占总渔获量的31.99%,其后依次为寡鳞飘鱼(Pseudolaubuca engraulis,10.09%),凤鲚(Coilia mystus,9.93%),睛尾蝌蚪虾虎鱼(Lophiogobiusocellicauda,8.92%),红狼牙虾虎鱼(Taenioides rubicundus,7.32%),焦氏舌鳎(Cynoglossus joyneri,5.32%)。渔获物中兼捕经济鱼类20种,平均每网24.10尾,占总渔获量的61.60%。同时采获鳗苗182尾,平均每采集1尾鳗苗,兼捕经济鱼类12.71尾。结果表明,鳗苗网的兼捕渔获物的种类和数量与作业的网具、地点、作业方式和潮汐相关。鳗苗网对经济鱼类早期发育阶段的个体损害较为严重,尤其对刀鲚幼鱼损害较大,这也是导致刀鲚成鱼资源量减少的重要原因之一,建议渔政管理部门应限制鳗苗网的数量和作业时段,并严格控制网目尺寸。
In order to assess the harmfulness of the Yangtze River mouth eel seedling net to bycatch of fish, from March to April 2011, 96 net sites of 8 eel seedling nets were collected at the Yangtze River estuary and 3 755 co-fishes were collected, belonging to 16 Section, 35 species. Among them, there are 12 species of marine fish, 14 species of estuarine fish, 3 species of migratory fish and 6 species of freshwater fish. The side-by-side development of tofu is juvenile and juvenile. Among them, Coilia nasus was the dominant species, accounting for 31.99% of the total catch, followed by Pseudolaubuca engraulis (10.09%), Coilia mystus (9.93%), tail tadpoles Lophiogobius ocellicauda (8.92%), Taenioides rubicundus (7.32%), Cynoglossus joyneri (5.32%). Catch 20 economically viable catch fish, averaging 24.10 tails each, accounting for 61.60% of the total catches. At the same time, 182 eel fry were harvested, with an average of 1 eel fry collected each time, and 12.71 economic fish were inoculated. The results showed that the species and quantity of bycatch catch in the eel seedling nets were related to the nets, locations, operating modes and tides. Eel Miao network on the early stages of economic development of fish individuals more serious damage, especially on the juvenile larvae greater damage, which is also contributed to reduce the cost of adult cuttlefish one of the important reasons, the proposed fishery management should limit the eel Miao network number and operation time, and strictly control the mesh size.