The bald eagle population has made an extraordinary recovery from its low in the 1960s. In 1995, The U.S. Fish and Wildlife Service upgraded the bald eagle's status from endangered to threatened in response to the recovery.

Several direct and indirect legal decisions paved the way: the National Emblem Act of 1940 (the Bald Eagle Protection Act), its listing on the Endangered Species Preservation Act of 1966 and subsequently on the Endangered Species Act of 1973, and perhaps most importantly, the Clean Water Act of 1972 and the banning of DDT the same year.

The National Park Service is collecting data from nestlings hatched within the Mississippi National River and Recreation Area and the St. Croix National Scenic Riverway to determine the persistence of various contaminants in these rivers. Researchers identify active nests, climb the trees, and obtain blood and feather samples from the eagle chicks.

Laboratory analysis of the blood and feather samples will provide insights into the levels of contaminants in the water and their effects on these apex predators and other animals within these river systems.

While the study is ongoing, there are preliminary results. More information can be found in the summary or the more detailed report (PDF, 1.03mb).

Stay tuned here for updates and as more information, images, and video clips become available.

Reports

Contaminants in Bald Eagle Nestlings Data Summary 2006-2008 (PDF, 1.03mb)

Videos

Taking Measurements of an Eaglet (Park Video, 36 seconds)

Baby Eagles Get a Check-Up (Fox9, 2:12 minutes)

Pictures

Eagle Survey Slideshow