美国俄亥俄州立大学边勃罗斯基教授发现，孵化场中养殖的大3数纸鱼苗常在释放于自然水城后不久相继死亡。他说：“孵化场不仅拥挤而且水质差，因而不利于鱼苗的生长。在孵化场中生长的鱼个］L小，身体弱、抗病力低．这些鱼苗在放入自然水域后常无力逃避捕食者，不能成功地觅食 Prof. Boloski, Ohio State University, found that the large-scale paperfish farms hatched in the hatchery died one after another shortly after they were released into nature. He said: "The hatchery is not only overcrowded but poor in water quality, which is detrimental to the growth of fry. The number of fish growing in the hatchery is small, weak and disease-resistant. Predators, can not successfully foraging