纪录片《我们的地球》 第176期 多样浅海(10)（在线收听）

The whale calf is now five months old.

小座头鲸现在有五个月大了。

He's almost doubled in size, and his days in his tropical nursery are coming to an end.

它的身材也大了一倍，在热带托儿所的日子也到头了。

It has been a warm and safe place in which to grow up,

在这个地方长大温暖而安全，

but there's nothing to eat here for his mother.

但在这里他的母亲无法吃到任何东西。

She has been living off her fat reserves for the last eight months, and she's close to starving.

她在过去的八个月里一直靠储存的脂肪存活，现在她临近饿死的边缘。

She must leave now, while she still has enough energy to guide and protect her calf, on the long voyage ahead.

她现在必须离开，趁她还有足够的能量在漫漫征途之中来指导和保护她的幼子。

All across the tropics, humpbacks are heading away from the Equator

横越热带，座头鲸调头离开赤道，

towards the rich temperate seas of both the southern and the northern hemispheres.

走向富饶而气候温和的南半球和北半球海域。

These are colder, rougher, and more dangerous waters.

这些是更冷、更狂暴、更多危险的水域。

Mother and calf must stay close.

母鲸和小鲸鱼必须靠得很近。

They can send sound signals to one another, above the roar of the ocean by slapping fins on the surface.

他们可以通过拍打海面，制造超越海洋轰鸣的的声音，以此相互传送声音信号。