首页
登录
职称英语
[originaltext]America’s national symbol--the Bald Eagle--almost went extinct 20
[originaltext]America’s national symbol--the Bald Eagle--almost went extinct 20
游客
2024-05-28
47
管理
问题
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 feasted on them. (29)DDT prevented eagle eggshells from thickening. The shells became so thin that they shattered before the babies hatched. Fortunately, in 1972, a law was passed to ban DDT, which saved the bald eagle from total wipeout. (30)And since then, wildlife biologists have reintroduced bald eagle eggs from Canada to America. The result was that last year US bird watchers 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. (31 ) But bald eagles still face tough times. The destruction of their natural homes could be the next DDT causing eagle numbers to drop quickly.
选项
A、They found ways to speed up the reproduction of bald eagles.
B、They developed new types of feed for baby bald eagles.
C、They explored new ways to hatch baby bald eagles.
D、They brought in bald eagles from Canada.
答案
D
解析
事实细节题。短文明确指出,自1972年以来,野生生物学家们从加拿大引进秃鹰,故正确答案为D)。
转载请注明原文地址:http://tihaiku.com/zcyy/3609718.html
相关试题推荐
[originaltext]Inaway,allofusareonaspaceship,theplanetEarth.We
[originaltext]Inaway,allofusareonaspaceship,theplanetEarth.We
[originaltext]M:Thinkaboutit,Mary.Throughtelecommunicationinformationtr
[originaltext]M:Thinkaboutit,Mary.Throughtelecommunicationinformationtr
[originaltext]W:HowwasyourtriptotheGrandCanyon?M:Itwasexcellent!We
[originaltext]W:Areyousureyou’vecorrectedallthetypingerrorsinthispa
[originaltext]W:Areyousureyou’vecorrectedallthetypingerrorsinthispa
[originaltext]W:Areyousureyou’vecorrectedallthetypingerrorsinthispa
[originaltext]W:Areyousureyou’vecorrectedallthetypingerrorsinthispa
[originaltext]W:Areyousureyou’vecorrectedallthetypingerrorsinthispa
随机试题
From:JuliaChen[j.chen@sanclerson.com]To:SandersonStaff-Lake
Nowadays,InternetenablesustoknowthingshappenalmostattheexactmomentA、
闭式喷头密封性能试验的试验压力为3.0MPa,保压时间不少于()min。A
下列哪种疾病所致的心力衰竭属于低排血量性心力衰竭A.扩张型心肌病 B.贫血
在下列软膏剂常用的附加剂中,还原势能小于软膏剂的活性成分,更易被氧化,从而能保护
脑瘤术后引流管拨出的时间一般为术后A.3~4天 B.5~7天 C.4~5天
易造成事故或对人员有伤害的场所的入口处,如()等处应设“未经许可不得入
某社会服务机构开展农村留守老人关爱服务,需要招募几名志愿者为患有白内障的老人进行
.鲁迅满怀悲愤的写道:“不是年青的为年老的写记念,而在这三十年中,却使我目睹许多
某客户通过证券公司介绍在期货公司开户,基于期货经纪合同产生的责任应由()对客户
最新回复
(
0
)