When “Silent Spring” by Rachel Carson was first published no one was aware of the chemical danger that was poisoning the environment and the far reaching affects it would have on both animal and human populations. It was the start of what would eventually become Earth Day, the formation of the Environmental Protection Agency (EPA) and the Endangered Species Act.
In her book, Carson exposes the havoc that pesticides have in the environment and specifically dichloro-diphenyl-trichloroethane commonly known as DDT. In June 1963 she was called to testify before a Senate subcommittee on pesticides. She stated that the pesticides introduced to the environment finds its way up the food chain to animals and humans.
The poison run off found its way to the streams, rivers and eventually the oceans. The population of animals that fed on the insects, small mammals, and fish began to lessen. It was found that the DDT affected the calcium structure of the eggs of birds and when nesting the parents crushed the eggs. The Bald Eagle was put on the Endangered Species list in 1995. Their population went from approximately 75,000 nesting birds in the lower forty-eight states in 1782 to 417 pairs in 1962. Illegal hunting also contributed to the decline. They are now off the Endangered Species list but are still threatened by hunting, collisions and electrocution.
Unfortunately, there continues to be a sizable list of endangered species and Wisconsin lists the Kirtland;s Warbler, a member of the clam family known as the Sheepnose, and the Hine’s Emerald Dragonfly.
There are still pesticides used in Wisconsin that threaten the environment. EPA has issued a warning bulletin to the farmers of the state. These pesticides are in the ground and on the plants that humans consume as well as the animals that humans eat. However, the conservation that started about fifty years ago is working.