英语听力：自然百科 澳大利亚大堡礁 Great Barrier Reef—16

 The pearl luggers then turned their attention to something else, a much bigger target. The reef has always provided a great haven¹ for large animals, like turtles who nest on the coral piece.

 

Whole populations of turtles were brought to the verge² of extinction³ by hunting them down for their valuable shells and meat. But despite now being protected, a new threat has begun to surface. The site of baby turtles hatching and raising for the sea may soon be a distant memory. Over the last few decades, evidence of our influence on the reef has become all too real. 

 

Marine⁴ biologist, Ove Hoegh-Guldberg, is on the frontline to protect it. Today he’s come to look for one of its greatest enemies, a single creature with the power to destroy the largest reef in the world.

 

"Relatively⁵, small changes in the conditions can cause some species to actually expire, and one of those is the Crown-of-thorns Starfish."

 

This evil-looking animal grows up to 3 feet across. It’s covered in sharp, venomous spines⁶, and its favorite food is coral. They can descend⁷ on the reef in their millions, swarming⁸ over it and eating it alive.  

 

"Like all starfish, it has the amazing ability to exude⁹ its stomach, trys feeding at this hole here, digest the coral and then suck up all the goodies, leaving essentially¹⁰ just the skeleton."

 

This starfish is capable of producing 6 million children every year. Normally very few survive. But now man has tipped the odds¹¹ in their favor. Fertilizers from inland farms have washed down from the rivers onto the reef. They made the perfect nutrient¹² for the baby starfish, and their numbers go through the roof. The population can explode to 2000 times its normal level.

1 haven   

n.安全的地方，避难所，庇护所

参考例句：

• It's a real haven at the end of a busy working day.忙碌了一整天后，这真是一个安乐窝。
• The school library is a little haven of peace and quiet.学校的图书馆是一个和平且安静的小避风港。

2 verge   

n.边，边缘；v.接近，濒临

参考例句：

• The country's economy is on the verge of collapse.国家的经济已到了崩溃的边缘。
• She was on the verge of bursting into tears.她快要哭出来了。

3 extinction   

n.熄灭，消亡，消灭，灭绝，绝种

参考例句：

• The plant is now in danger of extinction.这种植物现在有绝种的危险。
• The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。

4 marine   

adj.海的；海生的；航海的；海事的；n.水兵

参考例句：

• Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
• When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。

5 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

6 spines   

n.脊柱( spine的名词复数 )；脊椎；（动植物的）刺；书脊

参考例句：

• Porcupines use their spines to protect themselves. 豪猪用身上的刺毛来自卫。
• The cactus has spines. 仙人掌有刺。 来自《现代英汉综合大词典》

7 descend   

vt./vi.传下来，下来，下降

参考例句：

• I hope the grace of God would descend on me.我期望上帝的恩惠。
• We're not going to descend to such methods.我们不会沦落到使用这种手段。

8 swarming   

密集( swarm的现在分词 )； 云集； 成群地移动； 蜜蜂或其他飞行昆虫成群地飞来飞去

参考例句：

• The sacks of rice were swarming with bugs. 一袋袋的米里长满了虫子。
• The beach is swarming with bathers. 海滩满是海水浴的人。

9 exude   

v.(使)流出，(使)渗出

参考例句：

• Some successful men exude self-confidence.有些成功的人流露出自信。
• The sun made him exude sweat.烈日晒得他汗流浃背。

10 essentially   

adv.本质上，实质上，基本上

参考例句：

• Really great men are essentially modest.真正的伟人大都很谦虚。
• She is an essentially selfish person.她本质上是个自私自利的人。

11 odds   

n.让步，机率，可能性，比率；胜败优劣之别

参考例句：

• The odds are 5 to 1 that she will win.她获胜的机会是五比一。
• Do you know the odds of winning the lottery once?你知道赢得一次彩票的几率多大吗？

12 nutrient   

adj.营养的，滋养的；n.营养物，营养品

参考例句：

• Magnesium is the nutrient element in plant growth.镁是植物生长的营养要素。
• The roots transmit moisture and nutrient to the trunk and branches.根将水分和养料输送到干和枝。