北极燕鸥是一种特别的鸟。迁徙时，它们从北极圈飞往南极圈，再飞回起点，整个旅程非比寻常，历时一年之久。这种鸟的迁徙路线在全球鸟类中属最长，但它们在途中也会停下来歇歇脚。北极燕鸥在英国北部繁殖，以北大西洋中部的鱼类为食，为漫长的旅程积攒体力。本期节目介绍这种鸟漫长而艰苦的迁徙之旅。

词汇：bird migration 鸟类迁徙

Back in 2010, an international research team fitted tracking devices to birds they believed to be special – Arctic terns. And it turns out they were right, as described in US journal, PNAS. The Arctic tern has an extraordinary year-long migration from the Arctic Circle to the Antarctic Circle and back again.

早在2010年，一个国际研究小组就在他们认为很特殊的鸟类——北极燕鸥身上安装了追踪装置。事实证明他们是对的，正如美国期刊《美国科学院院刊》所描述的那样。北极燕鸥从北极圈到南极圈之间进行为期一年的非同寻常的迁徙，然后再返回。

What does this route look like? Arctic terns begin their migration in the Northern hemisphere in the summer, which is breeding season. As it gets colder and darker, turning to winter, the birds fly southward, parallel to the coast of South America or hugging the coast of the African continent to reach their winter feeding ground, the Antarctic Circle. And they do not always fly in a straight line. While heading back up north, their flight path mimics an S-shape which they follow to save energy while navigating the wind systems in the different hemispheres. This journey is a round-trip of up to 35,000km long, which makes the Arctic tern's migration the longest of any bird. Plus, they see more daylight than any other animal on Earth!

这条路线是什么样的?夏季是北极燕鸥的繁殖季节，它们开始在北半球迁徙。随着天气越来越冷，越来越黑，进入冬季，这些鸟向南飞行，与南美洲海岸平行，或拥抱非洲大陆的海岸，到达它们的冬季觅食地——南极圈。而且它们并不总是直线飞行。当它们返回北方时，它们的飞行路线模仿s形，在不同半球的风系统中航行时，它们遵循s形飞行以节省能量。这是一次长达35,000公里的往返旅程，这使得北极燕鸥的迁徙成为所有鸟类中最长的。此外，它们比地球上任何其他动物都能看到更多的日光!

But, on this epic journey, the birds do take some well-deserved breaks. Heading northward, the population stops on the north and west coast of the UK to breed. A female lays one to three eggs in a nest, and after an incubation period of around three weeks, they hatch, and fluffy brown and grey chicks emerge. Meanwhile, the adult birds feed in the shallow coastal waters on fish, such as sand-eels. In contrast, while heading south, the birds appear to stop off in the middle of the North Atlantic Ocean, where they indulge on fish and zooplankton, preparing themselves for their long journey ahead.

但是，在这段史诗般的旅程中，鸟儿们确实得到了一些应得的休息。它们向北迁徙，在英国北部和西海岸停留繁衍后代。一只雌鸟在巢中产下一到三个蛋，经过大约三周的孵化期后，它们孵化出来，生出毛茸茸的棕色和灰色的小鸡。与此同时，成年鸟在浅海水域以沙鳗等鱼类为食。相反，当它们向南飞行时，它们似乎会在北大西洋中部停留，在那里尽情享受鱼类和浮游动物，为未来的长途旅行做准备。

So, if you ever see a little black and white bird with red legs and a red beak, show them some appreciation. They have flown a long way to see you! 

所以，如果你看到一只黑色和白色的小鸟，红腿和红嘴，向它们表示感谢。他们飞了很长的路来看你!

词汇表

tracking device 跟踪装置
Arctic tern 北极燕鸥
migration 迁徙
Arctic Circle 北极圈
Antarctic Circle 南极圈
route 路线
Northern hemisphere 北半球
breeding 繁殖
southward 向南地
continent 大陆
feeding ground 觅食地
flight path 飞行路线
wind system 风系
round-trip 往返旅程
lay 产（蛋）
nest 鸟窝，鸟巢
incubation 孵化
hatch （雏鸟）孵出，破壳而出
chick 雏鸟
stop off 中途停留
zooplankton 浮游动物
beak （鸟）嘴，喙

测验与练习

1. 阅读课文并回答问题。

1. How long is the migration of an Arctic tern?

2. Why do the birds fly south in the winter?

3. True or False? When flying north, Arctic terns fly in a straight line.

4. Where and why do the birds stop in the UK?

5. What do Arctic terns eat?

2. 选择意思恰当的单词或词组来完成下列句子。

1. We're travelling up the country but don't know which _______ to take.  

route                       continent                          migration                 beak

2. Unfortunately, microplastics have been found in the _______ of many fish.    

round-trip                feeding grounds               flight paths              wind systems

3. I can't swim, so I usually stay in the _______ end of the pool.  

north                       southward                        shallow                    fluffy

4. We watched two birds building a _______ in the oak tree in our garden.

chick                       zooplankton                     nest                          incubation

5. The children were allowed to _______ the penguins at the zoo today!

lay                           hatch                                breed                       feed

答案

1. 阅读课文并回答问题。 

1. How long is the migration of an Arctic tern?
The Arctic tern has an extraordinary year-long migration.

2. Why do the birds fly south in the winter?
Because it gets colder and darker in the Northern hemisphere.

3. True or False? When flying north, Arctic terns fly in a straight line.
False. While heading back up north, the flight path mimics an S-shape.

4. Where and why do the birds stop in the UK?
The population stops on the north and west coast of the UK to breed.

5. What do Arctic terns eat?
Fish, such as sand-eels, and zooplankton.

2. 选择意思恰当的单词或词组来完成下列句子。

1. We are travelling up the country but don't know which route to take.

2. Unfortunately, microplastics have been found in the feeding grounds of many fish.

3. I can't swim, so I usually stay in the shallow end of the pool. 

4. We watched two birds building a nest in the oak tree in our garden. 

5. The children were allowed to feed the penguins at the zoo today!

文章来源BBC，侵权删，本文仅用于英语学习。