Lower levels of oxygen in water could lead to a higher ratio of male fish which might threaten certain fish species with extinction, according to a study result announced Wednesday by the City University of Hong Kong.

A recent discovery showed that oxygen depletion, or hypoxia as it is known, could lead to more male fish and an imbalance in the sex ratio. Such a discrepancy would have a dramatic impact on the reproductive success of certain fish, and could mean population decline and possible extinction.

This is the first ever report in the world of science that suggests hypoxia can affect the sex development, sex differentiation and sex ratio in an animal, and the result has been published in an international academic journal "Environmental Science and Technology."

中文翻译：

周三，香港城市大学的一份研究表明，水中的低氧环境会使雄鱼数量过多，可能会导致某些种类的鱼消失灭亡。

一个最新的发现表明，氧气的消耗或者氧气不足，可能会导致雄鱼数量多余雌性，并造成性别比例的失衡。这个失衡会直接影响某些鱼种的成功繁殖，引起数量的减少，并可能消失。

这是科学界首次报道在动物中，氧气不足会影响性别的发展，性别的差异和性别的比例失衡。该研究结果已经被一国际学术杂志“环境科学技术”发表。