Have you seen this bird?

Description: Large dark bird with white head and tail; wingspan 6 to 7 feet; seen most frequently near water.More and more people in Maryland do each year, as the bald eagle becomes somewhat common here and throughout the country.

Once endangered, our national symbol's numbers have increased dramatically over the past two decades. In Maryland, the number of nesting eagles has increased sixfold since the mid-1970s, with 260 pairs nesting in 1999 (compared to 41 pairs in 1977).

Why such a significant increase? The ban on the use of DDT and other organochlorine pesticides in 1972 by the U.S. Environmental Protection Agency started the recovery. DDT caused the eagles to lay thin-shelled eggs, which cracked when the eagles incubated them. Cracked eggs do not produce young.

Once this pesticide was no longer used, the environment was able to slowly rid itself of the contaminant and eagles started to nest successfully. Nest sites were protected by the Maryland Department of Natural Resources (DNR), the U.S. Fish & Wildlife Service, and others under the authority of the Endangered Species Act and, in Maryland, under the authority of the State's Endangered Species Act and the Critical Area Program.

In the Chesapeake Bay area, the eagle recovery was further enhanced by efforts to restore the bay. Better water quality helps sustain fish populations the principal diet of eagles.

Today, more than 2,000 bald eagles make their home in the Chesapeake Bay area. In 1999, Maryland's 260 nesting pairs of eagles produced 370 young; that's 890 nesting eagles and young in Maryland alone, and Virginia had comparable numbers. And these totals do not include the numerous immature eagles, one to four years old, wandering around the bay.

More on eagles!

Glenn Therres is the DNR Program Manager for Heritage and Biodiversity Inventory, Research & Monitoring. For more information about Maryland wildlife check out www.dnr.state.md.us/wildlife

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