Baikal is the oldest lake in the world 贝加尔湖是世界上最古老的湖泊
Brooding young in the mouth is a very effective way of protecting them. 它们将鱼苗含在嘴里 这是一种保护它们的有效方法
This is one of the largest concentrations of Nile crocodiles in Africa, 这里是非洲一处最大的尼罗鳄聚集地
there is real strength in numbers. 群体合作能保证它们屡战屡胜
is greater than any other stage in a river's life. 在河流扮演的角色中 这才是最主要的
This Canadian bear is very special - 这只加拿大熊很特别
But catching salmon in deep water is not that easy 但要想在深水中捕获鲑鱼可不太容易
This is the world's largest fresh water fish migration. 这是世界上规模最大的淡水鱼洄游