英语听力：自然百科 阿布扎比海牛

 From the sculpted 1 beauty of dessert dunes 2 to the undersea realms of the Persian Gulf 3, the United Arab Emirates is a study in contrast.

And while most people associate Arabia with desert life, the region is in fact teeming 4 with marine 5 animals as well, and perhaps none more intriguing 6 than the dugong. Its nickname is the sea cow. And like its namesake, it spends hours each day grazing.
 
Dugongs ply 7 the warm shallow waters off the coast, feeding along seemingly endless beds of waving sea grass. Their cylinder-shaped bodies measure more than 10 feet in length and fully 8 grown that can weigh in at over 800 pounds.
 
In the sea grass beds they seem bulky, placid 9 and content, but conservationists are worried. Some of these creatures share the coastline with the largest of the emirates Abu Dhabi. Over a million people live here and that number is swelling 10 by over 50,000 each year.
 
New buildings sprout 11 from the sands and engineers drive back the sea to house the burgeoning 12 population. All this prime real estate comes at a cost not just to the buyers but to the marine environment as well.
 
Dredging and construction leach 13 silt 14 into the gulf which chokes corals. Worse for the dugongs, the silt smothers 15 the sea grass, covering their food supply with a blanket of debris 16 and pollution. The sea grass beds are dying.
 
It's a potential threat because these so-called seacows need to consume huge amounts of seagrass in order to survive. The underwater vegetation has a very low nutritional 17 value what dugongs lack in quality they make up for in vast quantities. An adult can eat almost 70 pounds of grass in a single day.
 
It's not only dugongs that suffer, the sea grasses also provide food and shelter for the endangered green turtle. And the sea turtle in turn provides transportation for fish called remoras. So with the sea grass beds buried, entire ecosystems 18 of marine creatures feel the impact.
 
But in the emirate of Abu Dhabi, it's the dugong population that is most in the spotlight 19. The species has already been listed as vulnerable to extinction 20. And this is part of the second-largest population remaining in the world. To lose these dugongs would be a further blow to an already beleaguered 21 species.
 
To find out what it will take to protect the dugongs, a government organization called the Environment Agency Abu Dhabi or EAD has been asked to investigate. The first priority is head count. More than 2000 dugongs spend their summers near Abu Dhabi. In the winter, the number swells 22 to almost 3000.
 
when a dead dungong washes up on shore, a team of scientists move in to examine the remains 23. First they measure the body and then take photographs. With the data collected, scientists try to determine the cause of death. Many of the animals are killed by boats. Others drown when they become entangled 24 in fishing nets.
 
Now that the authorities know where the dugongs are and how they're being impacted, they can continue to make plans to keep them safe.
 
When a lot of pressure came into the marine environment, the population declined. So, today we have a well established strategy for conservation of the dugong.
 
A major part of the conservation area is a marine protected area in the region with the densest 25 population of dugongs. It's one of the largest sanctuaries 26 of its kind in the Middle East.