“A Year of Birding in Bloedel” is a column that runs every Friday in the Bainbridge Islander. The project is planned to continue in 52 parts through 2014 to help readers find and identify birds in the island’s garden sanctuary. Beginning with this entry on the bald eagle, each column will also be published here on the Bainbridge Conversation blog each Friday.
The author, Ted Anderson, is a retired professor of biology, having taught at McKendree University (Ill.) for 32 years and for the University of Michigan’s summer biological station for 20 years, where he frequently taught the biology of birds.
Anderson is also the author of “Biology of the Ubiquitous House Sparrow, from Genes to Populations” (2006), and “The Life of David Lack, Father of Evolutionary Ecology” (2013). Ted and his wife Carol have been members of Bloedel Reserve for 7 years. They live in Kingston.
A bald eagle sits in a tree overlooking Eagle Harbor on Bainbridge Island. (MEEGAN M. REID/KITSAP SUN)
Beginning in 2005, visitors to Bloedel were treated to wonderful views of the majestic bald eagle (Haliaeetus leucocephalus) at a nest near the top of a tall Douglas Fir near the shore of Puget Sound behind the visitor’s center. The nest activity could be viewed from windows in the visitor’s center, or, at closer range, near the birch grove down the hill.
The former director, Richard Brown, took numerous photos of the nesting eagles, many of which are still on display in albums in the library of the Visitor’s Center. In July 2013, however, this magnificent, living display ended when the nest tree snapped off, dumping the nest and a full-grown but flightless eaglet, apparently unhurt, onto the beach below. The adults continued to feed their youngster on the beach until it was able to fly.
Long an important element of he cultures of many Native American tribes, the bald eagle was chosen as the national emblem of a fledgling new nation by the Continental Congress in 1782. This act did not come with an order of protection, however, and later bounties were established for the bald eagle and many other top predators including other birds of prey, wolves, coyotes and bears. Eagle numbers dropped dramatically due to this persecution, and eagles virtually disappeared from many parts of the lower 48.
Widespread use of DDT in the 1940s through the 1960s further reduced their numbers, driving them to near extirpation in the lower 48. DDT residues in the fat bodies of fish had a devastating effect on many top predators in the aquatic food chain due to a process known as bioamplification. The residues interfered with calcium metabolism in the eagles resulting in the thinning of their eggshells and resultant egg breakage and nest failure.
When the Endangered Species Act was passed in 1973 the bald eagle was one of the first species placed on the endangered species list. With the almost simultaneous ban on many uses of DDT the bald eagle population began a dramatic recovery in the continental United States. One of only a few such successes, the Bald Eagle was removed from the endangered species list in 2007. Many Americans who had never seen their national emblem in the wild now have had the opportunity to enjoy seeing this magnificent bird.
The Bloedel pair is still active in the areas near their old nest site. Listen for their high-pitched screeches emanating from the wilderness area adjacent to the site or from the conifers near the birch grove. They typically lay their eggs in February and the pair is now in active courtship.