首页
登录
职称英语
[originaltext] America’s national symbol, the bald eagle, almost went extinc
[originaltext] America’s national symbol, the bald eagle, almost went extinc
游客
2023-09-03
59
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 U. S. 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. 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. 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. The destruction of their natural homes could be the next DDT causing eagle numbers to drop quickly.
选项
A、Pollution of the environment.
B、A new generation of pest killers.
C、Over-killing by hunters.
D、Destruction of their natural homes.
答案
D
解析
转载请注明原文地址:https://tihaiku.com/zcyy/2981434.html
相关试题推荐
[originaltext]Theyearis2094.Ithasbeenannouncedthatacometisheadingt
[originaltext]Theyearis2094.Ithasbeenannouncedthatacometisheadingt
[originaltext]Facialexpressionscarrymeaningthatisdeterminedbysituat
[originaltext]Facialexpressionscarrymeaningthatisdeterminedbysituat
[originaltext]W:DoestheMotorVoterLawcoverallthestates?M:No.W:Which
[originaltext]W:DoestheMotorVoterLawcoverallthestates?M:No.W:Which
[originaltext]M:MissHanson,thankyouforsendingmethisnote.I’msorryto
[originaltext]M:MissHanson,thankyouforsendingmethisnote.I’msorryto
[originaltext]M:MissHanson,thankyouforsendingmethisnote.I’msorryto
[originaltext]M:MissHanson,thankyouforsendingmethisnote.I’msorryto
随机试题
Heknowslittleofphysics,and______ofmath.A、evenmoreB、stilllessC、noles
Whatdoesitmeantoobeythelaw?That【B1】______whereyouare.Differentcu
ping127.0.0.1用于检查()。A.网卡连接状态 B.到网关的连接
下列进度控制的基本程序中,顺序正确的是()。1、承建单位编写阶段性进度计划2
法洛四联症最具特征性的超声征象是A.主动脉前壁与室间隔连续性中断,主动脉骑跨于室
移动平均线指标的特点是() Ⅰ.追踪趋势 Ⅱ.滞后性 Ⅲ.被动性 Ⅳ.助
可用于治疗肠道内、外阿米巴感染的药物是A:头孢拉定 B:酮康唑 C:甲硝唑
2型糖尿病患者,女,60岁,因服用降糖药达格列净出现尿路感染就诊,医师建议改用胰
项目财务计划现金流量表主要用于分析项目的()。A.偿债能力 B.财务生存
关于医德良心,下述提法中错误的是A.医德良心是对道德情感的深化 B.医德良心是
最新回复
(
0
)