虎鲸是在海洋食物链的最高层,它习惯于捕食抹香鲸和须鲸。当虎鲸不能再捕食它们的时候,它就被迫捕食处于更下一层的食物链。她们先捕食的是最容易捕捉且最有营养价值的海豹。
Then, when seals became rare, the killer whales turned to sea lions. When the sea lionpopulation crashed, they started fishing sea otters. The domino effect reaches even farther. Without sea otters keeping sea urchins in check, their population has exploded. And theyve destroyed the kelp forests, and with it, the kelp forest ecosystem in southwestern Alaska.
接着,当海豹变得稀少后,虎鲸便转向了海狮。而又当海狮的数量变少后,虎鲸又开始猎杀海獭了。多米诺效应又继续延伸。没了海獭约束海胆,海胆的数量变得庞大起来。并且破坏阿拉斯加啊西南部的海藻林生态系统。
Animals switching food sources can have a very serious effect on the environment. And that we humans, as the ultimate predators, need to give a lot of thought to the choices we make. They may affect the food web in unintended ways.
动物间交换食物来源对环境有着很严重的影响。而作为终极捕食者,人类需要好好思考一下他们所做的选择。这些选择可能会以人们所不知道的方式来影响食物网。
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