Question

DDT was developed as a synthetic insecticide. It was used to kill insects across the United States. In 1972, DDT was banned for use in the United States because it was found to cause egg shell thinning in bald eagle. In 3-5 sentences explain how introducing DDT into an ecosystem allowed it to make its way into the bodies of bald eagle. Be sure to use the terms food chain, producers, biomagnification, secondary consumers, and tertiary consumers in your answer.

Answer 1

When DDT was sprayed it entered aquatic and terrestrial food chains by being absorbed or deposited on producers (algae and plants), where small herbivores feeding on them took it up. Those primary consumers were eaten by secondary consumers, which in turn were eaten by tertiary consumers like bald eagles. Because DDT is persistent and fat-soluble, its concentration increases at each step through biomagnification, so higher trophic levels accumulate much more DDT than producers or primary consumers. As a result, bald eagles as top (tertiary) consumers accumulated dangerous DDT levels that caused eggshell thinning and population declines.