纪录片《我们的地球》 第238期 偏远岛屿(09)（在线收听）

The surrounding sea, however, is particularly rich with life.

然而环岛的海中却孕育着丰富的生命。

And the frontier between these two very different worlds is the home of one of the strangest of reptiles.

而这两个不同世界的交界处生活着最奇异的爬行动物。

Seagoing iguanas. They are vegetarians,

海鬣蜥。它们是素食者，

but since there's little food for them on the land, marine iguanas graze on the sea floor.

但由于岛上没有能吃的食物，所以海鬣蜥以海底的植物为食。

A big male like this one can dive to 30 metres and hold his breath for half an hour.

这种体型的雄性海鬣蜥可潜到水下三十米，屏住呼吸长达半小时。

There are more than 7,000 individuals on Fernandina alone.

仅在费尔南迪纳岛上就有超过七千只海鬣蜥。

And by bringing nutrients from the sea to the land,

它们往返近海获取食物养活自己，

the iguanas help other animals to survive here, too.

同时还帮助了其它动物在此生存。

Crabs feed on dead skin on the iguana's back,

红石蟹以海鬣蜥背上的死皮为食，

and, in turn, provide a welcome exfoliation service.

反过来也热情地为它们提供去角质服务。

While smaller lizards prey on the flies that pester the colony.

小型蜥蜴还捕食纠缠海鬣蜥的苍蝇。