The bald eagle (Haliaeetus leucocephalus) is the famous national animal of the United States, appearing on American currency and the coat of arms. Its name derives from an older meaning of the word “bald,” to mean “white-headed” – bald eagles are dark brown with a white head and tail. Bald eagles build the largest tree nests of any animal species on the planet, which can be up to 13 feet deep and 8 feet wide.
Today, the species can be found in every continental state and province of the United States and Canada, as it is able to live in a wide variety of habitats. However, our national animal faced a crisis in the mid-20th century, when the number of nesting pairs of bald eagles in the lower 48 states fell to just 412.
This huge population decline was caused by a pesticide called DDT, which was widely used in farming. Unfortunately, once DDT entered the body of a bald eagle, it caused them to lay eggs that had unnaturally thin shells. When an adult eagle sat on these eggs in the nest, their brittle shells cracked and so the eggs never hatched.
The book Silent Spring by Rachel Carson, published in 1962, brought attention to the destruction that DDT was causing in the environment. Silent Spring quickly became a bestseller and even attracted the attention of President John F. Kennedy. In 1973, the US Environmental Protection Agency banned the use of DDT, and the bald eagle population rebounded. It is estimated that there are nearly 200,000 bald eagles in the wild today.
The story of the bald eagle is an inspiring one that proves how collective effort can establish conservation programs that are hugely successful. Other species that are endangered today should be allowed the same kind of success story that the bald eagle has.
Take time today, on American Eagle Day, to learn about conservation: take a look at our Animal Diversity lesson (grades K-2), Preserving Health through Biological Diversity lesson (grades 9-12), and our Why Are Species Endangered? and Working to Save Endangered Species lessons (both grades 6-8).
Image credit: Clipart.com
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