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黑鱼(乌鳢)栖息于温度高、水草较多的静水水域,常潜伏在浅水水草多的水底,对水质、温度和其他外界环境的适应性特别强。由于具有辅助呼吸器官,能呼吸空气中的氧气,所以在低氧的水域也能生活,甚至在完全没氧的水中也能生活6—8小时之久。离开水后,只要保持腮腔和体表湿润,仍可较长时间地生后。 黑鱼是一种凶猛的肉食性鱼类。生长速度相当快,最大个体重达5kg以上。由于生长环境不同,生长速度也不一。在人工饲养条件下,当年鱼体重可达0.25kg,两年可达
Black fish (black jackal) habitat in the high temperature, aquatic plants more static waters, often lurking in the shallow water plants and more water, the water quality, temperature and other external environment adaptability particularly. Owing to the accessory respiratory organs, it can breathe the oxygen in the air, so it can live in the low-oxygen waters and even live in the completely oxygen-free water for 6-8 hours. Leave the water, as long as the maintenance of cheek cavity and body surface moist, still a long time after the birth. Blackfish is a ferocious carnivorous fish. Very fast growth, the largest individual weighing more than 5kg. Due to the different growth environment, the growth rate is not uniform. Under artificial breeding conditions, the weight of fish up to 0.25kg, up to two years