WASHINGTON — Populations of the American bald eagle — the bold national symbol of the United States — have quadrupled since 2009, according to a new report by the U.S. Fish and Wildlife Service and its partners.
Bald eagles once teetered on the brink of extinction, reaching an all-time low of 417 known nesting pairs in 1963 in the lower 48 states. However, after decades of protection, the banning of the pesticide DDT and conservation efforts with numerous partners, the bald eagle population has flourished, growing to more than 71,400 nesting pairs.
According to scientists from the service’s Migratory Bird Program, the bald eagle population climbed to an estimated 316,700 individual bald eagles in the lower 48 states. This indicates the bald eagle population has continued to increase rapidly since our previous survey.
The information is now available in the new technical report: U.S. Fish and Wildlife Service final report: bald eagle population size: 2020 update.
To estimate the bald eagle population in the lower 48 states, Migratory Bird Program pilot biologists and observers from many service regions, programs and contract observers conducted aerial surveys over a two-year period in 2018 and 2019. The service flew aerial surveys over high-density eagle nesting areas to generate accurate estimates and count occupied nesting territories.
To obtain information on the lower density eagle nesting areas, the agency worked with the Cornell Lab of Ornithology to use eBird relative abundance data to acquire information on the areas that were not practical to fly as part of the aerial surveys.
Based on those two major sets of data for this population estimate, the service next created an integrated population model to expand the estimates of the number of occupied nests across the plot area to estimates of the entire population in the lower 48 states. Information on survival rates, productivity and breeding rates provided the information needed to make this conclusion.
This technical report is the second in a series of reports that have been published on bald and golden eagles. For more information on bald eagle management and additional background, visit the Eagle Management page.
