北極燕鷗是一種特別的鳥。遷徙時，它們從北極圈飛往南極圈，再飛回起點，整個旅程非比尋常，歷時一年之久。這種鳥的遷徙路線在全球鳥類中屬最長，但它們在途中也會停下來歇歇腳。北極燕鷗在英國北部繁殖，以北大西洋中部的魚類為食，為漫長的旅程積攢體力。本期節目介紹這種鳥漫長而艱苦的遷徙之旅。

詞匯：bird migration 鳥類遷徙

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.

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!

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.

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! 

詞匯表

tracking device 跟蹤裝置
Arctic tern 北極燕鷗
migration 遷徙
Arctic Circle 北極圈
Antarctic Circle 南極圈
route 路線
Northern hemisphere 北半球
breeding 繁殖
southward 向南地
continent 大陸
feeding ground 覓食地
flight path 飛行路線
wind system 風系
round-trip 往返旅程
lay 產（蛋）
nest 鳥窩，鳥巢
incubation 孵化
hatch （雛鳥）孵出，破殼而出
chick 雛鳥
stop off 中途停留
zooplankton 浮游動物
beak （鳥）嘴，喙

測驗與練習

1.  閱讀課文并回答問題。

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.  選擇意思恰當的單詞或詞組來完成下列句子。

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. 閱讀課文并回答問題。 

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.  選擇意思恰當的單詞或詞組來完成下列句子。

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!