纪录片《我们的地球》 第374期 奇迹城市(16)（在线收听）

Losing its fear of humans has enabled one animal to spread into cities everywhere, and in huge numbers.

丧失对人类的恐惧，让一种动物遍布世界各个城市，而且数量庞大。

Pigeons are by far the most successful urban bird.

鸽子是目前最成功的城市鸟类。

Here, in Albi, in the south of France, the pigeons come to the river to bathe.

在法国南部的阿尔比，鸽群飞到河边沐浴。

They need to preen their flight feathers,

它们要整理飞羽，

clean off the city dust, and cool themselves down.

清洗掉城市的灰尘，并给自己降降温。

But death lies in wait.

而死神正埋伏以待。

A predator that has taken advantage of the very thing that has led to the pigeon's success.

捕食者正是利用了鸽子在城市得以成功生存的法宝。

Their lack of fear.

它们已丧失的恐惧感。

As the pigeons bathe, oil from their plumage flows downstream, and is detected.

鸽子洗澡时，羽毛上的油脂顺流而下，被捕食者察觉。

A monstrous Wels catfish.

一条巨大的六须鲶鱼。

Introduced here just 40 years ago, they have proliferated.

虽然才被引入此地四十年，繁殖数量却已大大增长。

Virtually exterminated the local fish stocks.

几乎迫使本地鱼类灭绝。

And they've now developed a taste for pigeon.

现在它们将猎食对象转向了鸽子。

Their eyesight is poor, so they use their barbels to sense the movements of their victims.

由于视力微弱，它们依靠触须来探测猎物的动静。

This is a radical new hunting strategy for what is normally a bottom-dwelling fish.

对底栖鱼类来说，这是种全新的捕猎策略。

After a thousand years of living in this city, pigeons are now having to learn to avoid a fish.

在城市居住了上千年之后，鸽子现在却要学会避开水里的鱼。