纪录片《非洲》 第71期:撒哈拉沙漠（12）（在线收听）

But the birds need to be careful,

但鸟儿们需要加倍小心

for the sun has played a terrible trick.

因为太阳开了一个可怕的玩笑

This oasis is poisonous.

绿洲里的水是有毒的

Intense evaporation over thousands of years

上千年的剧烈蒸发

has left the water saltier than the sea.

使得此片水源的盐度超过了海水

As if to underline the horror,

更为恐怖的是

the place is infested by vast swarms of flies.

大量的苍蝇聚集于此

But this plague is a birds' salvation.

然而这些疫虫是候鸟们的救星

The flies are filled with freshwater, filtered from the brine.

它们能将盐水过滤 使体内充满淡水

So, like a desert wanderer squeezing a drink from a cactus,

就像沙漠迷途者挤压仙人掌摄取水分那样

the birds get all the water they need from the flies' bodies.

鸟儿们通过捕食苍蝇来获取淡水

More and more migrants join in.

越来越多的候鸟加入了捕食行列

Wagtails.

比如鹡鸰