VOA慢速英语--官员努力控制亚洲鲤鱼在美国河流中的扩散

Officials Struggle to Control Spread of Asian Carp in American Rivers

Wildlife officials at a lake in Kentucky recently used electric shocks and sound to lead huge groups of Asian carp into large nets.

This was the latest effort in a 15-year battle to halt the spread of the fish in the United States.

The Asian carp is an invasive species that threatens to damage underwater ecosystems¹. The carp compete for food that native fish eat. They are also blamed for harming endangered mussels and snails² along the Mississippi River and other waterways.

The Associated Press, or AP, examined data from state and federal agencies about the cost of efforts against Asian carp. The AP found that together they have spent nearly $607 million to stop the fish since 2004. Proposed projects are expected to increase that cost to about $1.5 billion over the next 10 years.

That is more than five times the amount predicted in 2007 when a national carp management plan was created. Programs aim to reduce established populations and prevent further spreading. But wildlife officials admit they may never be able to stop the fish.

Much has been done to limit the carps' movement northward³ and to keep them out of the Great Lakes. Experts say they could severely⁴ damage the fishing industry in those bodies of water. The effort includes a proposed underwater electric barrier near Chicago and genetic⁵ testing. It also includes payments to commercial fishers and other experiments to harvest the fish.

The effort has mostly been successful, yet the lakes remain at risk and grass carp have been identified in Lake Erie, Lake Ontario and Lake Michigan.

Less money and attention have gone to the carp's nearly unlimited⁶ spread east and west into the Missouri and Ohio rivers.

The term "Asian carp" describes four different species: bighead, black, grass and silver carp. The carp were imported to the U.S. in the 1960s and 1970s as a way to deal with unwanted water plants and parasites⁷. But the fish escaped into many American waterways.

Joel Brammeier is president of the activist⁸ group Alliance for the Great Lakes. He said, "...Biologists understood the risks of bringing live, non-native animals into the country. It should never have happened."

Greg Conover is a U.S. Fish and Wildlife Service biologist. He oversaw⁹ the development of the national Asian carp plan. He saw how many there were in the Mississippi River as he studied native paddlefish in the 1990s.

"At first there were no carp, then we were catching¹⁰ a few carp here and there, then eventually we were filling the nets with carp and no paddlefish," he said.

Scientists say that Asian carp in the upper Mississippi River are pushing out valuable native fish such as yellow perch¹¹ and bluegill. And people who fish for sport say they are seeing the effects.

Kevin Irons is with the Illinois Department of Natural Resources. He said control efforts have been successful in the parts of the Illinois and Des Plaines rivers. He noted¹² that a combination of methods including commercial fishing have removed hundreds of thousands of kilograms of fish from those rivers close to Lake Michigan.

To prevent carp from moving northward into Lake Michigan, the U.S. Army Corps¹³ of Engineers is proposing the most costly¹⁴ effort to date. It is an electric barrier near Chicago that also would produce air and noise underwater. Congress is considering the plan which would cost more than $800 million.

At the same time, southern states are increasing efforts to control the fish. Tennessee hired its first aquatic¹⁵ nuisance species coordinator¹⁶ in December. In Kentucky, officials put in place an experimental underwater barrier last November designed to block Asian carp at a lake on the border of Kentucky and Tennessee.

Words in This Story

net(s) – n. a device that is used for catching or holding things or for keeping things out of a space and that is made of pieces of string, rope or wire linked together with spaces in between

invasive – adj. likely to spread

species – n. a group of animals or plants that are similar and can produce young animals or plants

ecosystem(s) – n. everything that exists in a given environment

management – n. the act or skill of controlling and making decisions about a business, department or sports team

commercial – adj. related to or used in the buying and selling of goods and services

parasite(s) – n. an animal or plant that lives in or on another animal or plant and gets food or protection from it

eventually – adv. at some later time

aquatic – adj. living or found in or near water

nuisance – n. a person, thing, or situation that is annoying or that causes trouble or problems

1 ecosystems   

n.生态系统( ecosystem的名词复数 )

参考例句：

• There are highly sensitive and delicately balanced ecosystems in the forest. 森林里有高度敏感、灵敏平衡的各种生态系统。 来自《简明英汉词典》
• Madagascar's ecosystems range from rainforest to semi-desert. 马达加斯加生态系统类型多样，从雨林到半荒漠等不一而足。 来自辞典例句

2 snails   

n.蜗牛；迟钝的人；蜗牛( snail的名词复数 )

参考例句：

• I think I'll try the snails for lunch—I'm feeling adventurous today. 我想我午餐要尝一下蜗牛——我今天很想冒险。 来自《简明英汉词典》
• Most snails have shells on their backs. 大多数蜗牛背上有壳。 来自《简明英汉词典》

3 northward   

adv.向北；n.北方的地区

参考例句：

• He pointed his boat northward.他将船驶向北方。
• I would have a chance to head northward quickly.我就很快有机会去北方了。

4 severely   

adv.严格地；严厉地；非常恶劣地

参考例句：

• He was severely criticized and removed from his post.他受到了严厉的批评并且被撤了职。
• He is severely put down for his careless work.他因工作上的粗心大意而受到了严厉的批评。

5 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

6 unlimited   

adj.无限的，不受控制的，无条件的

参考例句：

• They flew over the unlimited reaches of the Arctic.他们飞过了茫茫无边的北极上空。
• There is no safety in unlimited technological hubris.在技术方面自以为是会很危险。

7 parasites   

寄生物( parasite的名词复数 )； 靠他人为生的人； 诸虫

参考例句：

• These symptoms may be referable to virus infection rather than parasites. 这些症状也许是由病毒感染引起的，而与寄生虫无关。
• Kangaroos harbor a vast range of parasites. 袋鼠身上有各种各样的寄生虫。

8 activist   

n.活动分子，积极分子

参考例句：

• He's been a trade union activist for many years.多年来他一直是工会的积极分子。
• He is a social activist in our factory.他是我厂的社会活动积极分子。

9 oversaw   

v.监督，监视( oversee的过去式 )

参考例句：

• He will go down as the president who oversaw two historic transitions. 他将作为见证了巴西两次历史性转变的总统，安然引退。 来自互联网
• Dixon oversaw the project as creative director of Design Research Studio. 狄克逊监督项目的创意总监设计研究工作室。 来自互联网

10 catching   

adj.易传染的，有魅力的，迷人的，接住

参考例句：

• There are those who think eczema is catching.有人就是认为湿疹会传染。
• Enthusiasm is very catching.热情非常富有感染力。

11 perch   

n.栖木，高位，杆；v.栖息，就位，位于

参考例句：

• The bird took its perch.鸟停歇在栖木上。
• Little birds perch themselves on the branches.小鸟儿栖歇在树枝上。

12 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

13 corps   

n.(通信等兵种的)部队；(同类作的)一组

参考例句：

• The medical corps were cited for bravery in combat.医疗队由于在战场上的英勇表现而受嘉奖。
• 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。

14 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

15 aquatic   

adj.水生的，水栖的

参考例句：

• Aquatic sports include swimming and rowing.水上运动包括游泳和划船。
• We visited an aquatic city in Italy.我们在意大利访问过一个水上城市。

16 coordinator   

n.协调人

参考例句：

• The UN Office for the Coordination of Humanitarian Affairs, headed by the Emergency Relief Coordinator, coordinates all UN emergency relief. 联合国人道主义事务协调厅在紧急救济协调员领导下，负责协调联合国的所有紧急救济工作。
• How am I supposed to find the client-relations coordinator? 我怎么才能找到客户关系协调员的办公室？