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
2023-09-07
37
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、It limited their supply of food.
B、It made their eggshells too fragile.
C、It destroyed many of their nests.
D、It killed many baby bald eagles.
答案
B
解析
事实细节题。原文提到,DDT使得蛋壳变得很薄,在小鹰孵化之前就碎了。由此可见DDT对秃鹰的危害是B)。
转载请注明原文地址:https://tihaiku.com/zcyy/2993451.html
相关试题推荐
[originaltext]Inaway,allofusareonaspaceship,theplanetEarth.We
[originaltext]Inaway,allofusareonaspaceship,theplanetEarth.We
[originaltext]Inaway,allofusareonaspaceship,theplanetEarth.We
[originaltext]Oneofthereasonsforoursuccessasaspeciesisourabilit
[originaltext]M:Thinkaboutit,Mary.Throughtelecommunicationinformationtr
[originaltext]M:Thinkaboutit,Mary.Throughtelecommunicationinformationtr
[originaltext]W:HowwasyourtriptotheGrandCanyon?M:Itwasexcellent!We
[originaltext]W:HowwasyourtriptotheGrandCanyon?M:Itwasexcellent!We
[originaltext]W:Areyousureyou’vecorrectedallthetypingerrorsinthispa
[originaltext]W:Areyousureyou’vecorrectedallthetypingerrorsinthispa
随机试题
[originaltext]W:2millionhighschoolseniorsaregearingupthisfalltoappl
防火分区隔墙两侧的防火阀距墙体表面不应大于()。A.200mm B.300m
女性患者,腹部不适伴腹胀。经腹壁超声检查示:肝、胆、脾及肾脏未见异常;腹腔内见一
需要、动机、兴趣、理想、信念和世界观等属于A.个人心理 B.个性倾向性 C.
《拙政园月到风来亭联》“爽借清风明借月;动观流水静观山”的作者是()。A.陶澍
下列哪个药材粉末水浸液在紫外灯下有蓝色荧光A.番泻叶 B.紫苏叶 C.侧柏叶
到目前为止,我国个人贷款业务的发展历经了起步、发展和规范三个阶段,其诱因不包括(
家长督促儿童开始早晚自己刷牙的年龄是( )。A.4岁 B.6岁 C.8岁
SDS(化学品安全技术说明书)是化学品生产或销售企业按法律要求向客户提供的有关化
A
最新回复
(
0
)