Bald eagle populations reached such low numbers in the 1960s that some biologists predicted their extinction in the continental United States; what action appears to have been most significant in reversing their decline?
A) Eagle sanctuaries were established to provide protection for nesting eagles.
B) Bounties on eagle predators were enacted.
C) The use of DDT was banned in the United States.
D) Eagles were reared in captivity until reaching an age of self-sufficiency and then returned to the wild.

Question

Quizplus · Accepted Answer

The use of DDT was found to cause thinning of eagle eggshells, leading to fewer young hatching successfully. This was a significant factor contributing to the decline of bald eagles in the United States. In 1972, DDT was banned in the US, leading to a significant recovery of eagle populations.

Bald Eagle Populations Reached Such Low Numbers in the 1960s