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鳗苗即鳗鲡(亦称河鳗,白鳝)的幼体,每年2月中下旬始见于上海长江口,5月中下旬结束,苗汛期约70—90天。鳗鲡是一种降海性(catadromous)洄游鱼类,分布于我国的这种河鳗为日本鳗鲡(Angailla japonica)。每年秋季(9—11月)在内陆水域肥育接近性成熟的亲鳗,纷纷集群,通过咸淡水交汇处,随水流游向深海产卵。受精卵经孵化,随海潮飘流约1年后,体重逐渐长到约0.15g,体长约50—70mm 的透明棒状体,春天由河口溯上陆地河川。白色透明的鳗苗(亦称玻璃鳗)不久转黑。约经4—5
Moray eels that eel (also known as river eel, eel) larvae, beginning in mid to late February each year, the Yangtze River estuary in Shanghai, the end of mid-May, seedling flood season of about 70-90 days. The eel is a catadromous migratory fish, which is found in our country as Angailla japonica. Each autumn (September-November) fattening in close proximity to sexual maturity in the inland waters, have clusters, through the intersection of fresh and brackish water, with the flow of deep-sea spawning. Fertilized eggs hatched, with the tide drift about 1 year later, the weight gradually grew to about 0.15g, body length of about 50-70mm transparent rod, the spring estuary traced back to the river. White transparent eel seedlings (also known as glass eel) turn black soon. After about 4-5