March 3, 2012
Last night was the annual dinner of the Juniata Clean Water Partnership group [www.jcwp.org]. The evening’s speaker is a biologist working in the field. He spoke about the comeback of the bald eagles to be removed from the endangered species list. It was fascinating. It sent me on a hunt for children’s books about this topic. I found some but if any of you can recommend such books, please share here. But I digress.
When a species becomes endangered, efforts to save them depend on identifying the cause. Often, it relates to a loss of habitat. For the bald eagle, it turned out to relate to the use of DDT–an effective pesticide that, as is usually the case when we find something to solve one problem, has costs as well as benefits. Here is a summary of science and policy relating to DDT: http://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/ddt-ext.html
DDT use was banned from use in the U.S. the same year that I graduated from high school, 1972. Note the caveat relating to use. If we faced a public health emergency, such as an outbreak of malaria, it might be used. Tipping the scales toward benefit over cost.
Those costs? For use as humans–nerve damage and other significant health harms summarized in the link above. For the bald eagle–The shells of the bald eagle’s unborn became so thin that just the act of the parent bird sitting on them caused the shell to crack. Hence, the new generation of eagles was eliminated.
Once the cause was identified, the efforts to bring the bald eagle back and restore their population involved humans climbing large trees to remove young eagles from a nest [nests that average six feet wide and 8-10 feet deep]. If there was only one young eagle in a nest, the bird was left in place. If there were 2 or more, one was carefully removed and taken to another location where bald eagles used to exist. With care and effort to assure that they had habitat to survive, the transplanted birds thrived. In 2007, the bald eagle was removed from the endangered species list. A success.
Let’s hope we aren’t creating conditions in some parts of our planet that will lead to us being the endangered species…
