首页
登录
职称英语
[originaltext][16] America’s national symbol, the bald eagle, almost went extin
[originaltext][16] America’s national symbol, the bald eagle, almost went extin
游客
2023-06-26
49
管理
问题
[16] America’s national symbol, the bald eagle, almost went extinct 20 years ago. But it has made a comeback. In fact, the US Fish and Wildlife Service is considering the possibility of taking it off the endangered-species list. Once, more than 50,000 pairs of bald eagles nested across the country. But by 1960, that number had fallen below 400. The chief killer was the widely used DDT. Fish soaked up DDT, died, and were washed up on shores, where bald eagles ate them up. [17] DDT caused eagle eggshells to weaken and crack. The shells became so thin that they cracked before the babies emerged from the eggs. The eagle had no defense against DDT. [18] Fortunately, in 1972, a law was passed to ban DDT, which saved the bald eagle from dying out. And since then, wildlife biologists have reintroduced bald eagles from Canada to America. The result was that last year U.S. birdwatchers counted 11,610 bald eagles in the country. If it were dropped from the endangered list, the bald eagle would still be a threatened species. That means the bird would continue to get the same protection—no hunting allowed, and no disturbing of nests. But bald eagles still face tough times. [19] The destruction of their natural homes could be the next DDT, causing eagle numbers to drop quickly.
Questions 16 to 19 are based on the passage you have just heard.
16. What do we learn about the bald eagle?
17. How did DDT affect the bald eagles?
18. What has been done to prevent bald eagles from dying out?
19. According to the passage, what will cause the number of bald eagles to decline?
选项
A、DDT.
B、The disturbing of nests.
C、Hunting.
D、The destruction of their natural homes.
答案
D
解析
转载请注明原文地址:http://tihaiku.com/zcyy/2784779.html
相关试题推荐
[originaltext]Wereyouthefirstorthelastchildinyourfamily?Orwere
[originaltext]Demographyisnotdestiny.Asthedebateoveraginggetsunde
[originaltext]Demographyisnotdestiny.Asthedebateoveraginggetsunde
[originaltext]Mathewlivedinabigcity,andalwayshadhishaircutbyth
[originaltext]Mathewlivedinabigcity,andalwayshadhishaircutbyth
[originaltext]W:Whatagreatday,don’tyouthink?M:Iguessso.Ihadn’tn
[originaltext]W:Whatagreatday,don’tyouthink?M:Iguessso.Ihadn’tn
[originaltext]W:Whatagreatday,don’tyouthink?M:Iguessso.Ihadn’tn
[originaltext]Chinesegovernmentisreadytocarryoutitsfirstnationals
[originaltext]Chinesegovernmentisreadytocarryoutitsfirstnationals
随机试题
A.incidentB.whenC.includeD.flightsE.i
Morethan40yearsago,LeeKuanYew【B1】______whatwasapoor,decayingco
Cultural________indicatesthathumanbeingshandtheirlanguagesdownfromoneg
Cultureisthesumtotalofallthetraditions,customs,beliefs,andwayso
[originaltext]W:MidwesternBank.Goodmorning.M:Hello.I’dliketoknowhow
ThemilitaryaspectoftheUnitedStatesCivilWarhasalwaysattractedthe
现代金融企业制度的目标中,()是基础,是金融资产状况和制度效力的直接表现。A.
ABC公司为A股上市公司,拟收购XYZ公司55%的股权,委托甲评估公司评估股权价
当前学前儿童科学教育的内容,主要包括______、______、______、_
2020年10月1日,习近平在联合国大会纪念北京世界妇女大会25周年高级别会议上
最新回复
(
0
)