April 22, 2005
Thanks to Rachel Carson
Because April 22 is Earth Day, we'll celebrate it by paying tribute to the one person most responsible for the fact that we have bald eagles and ospreys to watch on our website -- Rachel Carson.
Although Rachel Carson grew up in Pennsylvania, she lived in Maryland for most of her life, so she is a local hero to those of us living in the state. In the first part of Carson's working life, she made a career with the U.S. Fish and Wildlife Service, eventually attaining the position of editor-in-chief of publications before retiring when she had the means to become a full-time author. During her writing career, she produced several popular books about the sea (including a National Book Award winner), but her most famous creation was her controversial 1962 work Silent Spring, in which she alerted the world to the dangers of the pesticide DDT and its deadly impact on both animals and humans.
Carson's book was based on a staggering amount of research, including work done at Maryland's own Patuxent Wildlife Research Center. The research done by the U.S. Fish and Wildlife Service there showed that DDT was working its way up the food chain and accumulating in the bodies of birds of prey -- particularly fish-eaters.
A pesticide applicator would spray DDT (a very popular pesticide in the 50s and 60s) in order to control mosquitos. Eventually the DDT washed into streams, rivers, and bays. The fish would feed on small animals contaminated by the pesticide, and after an eagle or osprey ate a large enough amount of fish, the pesticide would accumulate in their system -- a process known as biomagnification. (Click on the graphic).
Once a bald eagle or osprey had enough DDT in its system, the pesticide's breakdown product -- DDE -- would begin to inhibit the production of calcium for the bird's eggshells, and the eggshells would come out too thin. The end result was often that the egg would not hatch or the raptor would sit on the egg and it would crack, ending the life of the chick inside.
During the height of DDT use in America, the populations of bald eagles, peregrine falcons, ospreys, pelicans and similar birds began to plummet. In the 1930s, the Chesapeake Bay area saw an average of 1 to 2 eaglets produced per nest, but by the 1960s that average dropped to 1 for every 5 active nests. In America as a whole, the bald eagle population in the lower 48 states had dropped to approximately 400 pairs by 1963.
Rachel Carson's book was the catalyst that began to change all that -- it created awareness, outrage, and eventually political action. Despite intimidation from the chemical industry, Carson wrote her book and then continued to speak out after its publication, eventually appearing in front of Congress. In 1963, Carson's work was officially validated by President Kennedy's Science Advisory Committee. Carson died of cancer in 1964, but she lived long enough to know that her book had made a difference -- in America and throughout the world. Today many give her credit for sparking the modern environmental movement.
In 1972 the EPA officially banned the use of DDT in America, as evidence had grown about its impact on wildlife, its cancer-causing properties in humans, and its impact on unborn children. Since the banning, amazing efforts have been made by the U.S. Fish and Wildlife Service and conservation groups to rehabilitate bird populations using tools such as the Endangered Species Act, habitat conservation, captive-hatching and transplanting of young birds. As a result, osprey and pelican populations have grown dramatically throughout the country, the peregrine falcon has been removed from protected status, and talks are under way to remove the bald eagle as well. In the Chesapeake Bay area, eagle pairs have grown from a low of around 80-90 pairs in 1970 to a 2004 count of almost 400 nesting pairs in Maryland alone. The numbers nationwide are equally impressive. (Click on the graphic).
In 1980 Rachel Carson was posthumously awarded the Presidential Medal of Freedom -- the highest civilian award in America. She earned the medal for having the courage to stand up to intense pressure from the chemical industry -- pressure that would have intimidated most scientists into abandoning the book and staying silent. But even when the attacks turned personal, Carson stood her ground, and those who love the bald eagle and the osprey will be forever in her debt.
Rachel Carson:
"We still talk in terms of conquest. We still haven’t become mature enough to think of ourselves as only a very tiny part of a vast and incredible universe. Now I truly believe that we in this generation must come to terms with nature, and I think we’re challenged, as mankind has never been challenged before, to prove our maturity and our mastery, not of nature but of ourselves.”
Read more about Rachel Carson:
Rachel Carson website
Rachel Carson National Wildlife Refuge
Read more about how birds have rebounded from DDT:
Bald Eagle
Osprey
Peregrine Falcon
Read the EPA's warning about DDT:
DDT
Happy Earth Day!
Lisa - webmaster