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八、鲶鱼我国本土野生鲶鱼常见的只有3种,即南方大口鲶、东北六须鲶、普通的小河鲶,此外还有人工的杂交鲶以及外来引种埃及鲶鱼。习性极其相近,都是水中较大型的肉食性有胃鱼。1.底层鱼类。白天多隐居在水底,夜晚和黎明前后才会到近岸或水的中上层活动觅食。2.眼小退化,趋暗畏光。鲶鱼眼小且视力严重退化,但对光线感觉却很敏锐,怕光,因此白天整天都会蛰伏水底阴暗处或洞穴内歇息,很少活动。3.小河鲶喜群居,野生的小河鲶喜群居,这是由于它的趋暗畏光的习性和为了保持种群的数量优势所致。
Eight, catfish There are only 3 common species of wild catfish in our country, namely, the southern catfish, the northeast catfish, the common small river catfish, in addition to the artificial hybrid catfish and the exotic introduced Egyptian catfish. Habit is extremely similar, are larger carnivorous water stomach fish. 1. Bottom fish. During the day more than secluded in the water, before night and before dawn to near shore or water activities in the upper foraging. 2 small eye degradation, dark fear light. Catfish are small and severely degenerated, but they are sensitive to light and afraid of light, so they rest dormant in the darkness or in the cave throughout the day, with little activity. 3. Catfish greyish hippocampus, wild river catfish hi gregarious, which is due to its dim light habits and in order to maintain the population of the number of advantages.