Once dangerously on the brink of extinction, bald eagle populations are thriving throughout the lower 48 states of the U.S. According to U.S. Fish and Wildlife Services (USFWS), in 1963, only 417 bald eagle nesting pairs remained. A recent report from USFWS' Migratory Bird Program estimates the population size to be 316,700 individual bald eagles in the lower 48 states. This number includes about 71,400 nesting pairs.
In a statement to USFWS, Deb Haaland—U.S. Secretary of the Interior—said, "Today's announcement is truly a historic conservation success story. Announcements like ours today give me hope. I believe that we have the opportunity of a lifetime to protect our environment and our way of life for generations to come. But we will only accomplish great things if we work together."
USFWS reports that this most recent population estimate is 4.4 times the number of eagles counted in 2009. To gain an updated population estimate, biologists from the Migratory Bird Program and many other observers conducted aerial surveys in 2018 and 2019. Researchers performed aerial surveys in both high- and low-density nesting areas to obtain the most accurate count. The Migratory Bird Program partnered with the Cornell Lab of Ornithology to utilize abundance data in areas unable to be accessed by aerial surveys.
The 2020 population estimate includes data from four regions: the Pacific (North) Flyway, Central Flyway, Mississippi Flyway, and Atlantic Flyway. More than half of the bald eagles estimated occur throughout the Mississippi Flyway. The Atlantic Flyway is the second most abundant region, followed by the Pacific Flyway and the Central Flyway.
According to USFWS, bald eagles were removed from the Endangered Species Act in 2007 after nearly 40 years of protection. After decades of habitat loss and degradation, and illegal shooting bald eagle populations declined. Additionally, as reported by USFWS, when DDT became an extensively used pesticide control method, bald eagle population numbers plummeted. The chemical pesticide didn't impact the birds directly; instead, it contaminated their food sources, resulting in the birds' inability to produce strong eggshells. Weak eggs would not survive incubation or could not thrive to hatch.
USFWS cites the federal DDT ban as the primary conservation action that allowed bald eagle populations to recover. Additional habitat protection and shooting regulations protected the revered birds as well.
USFWS Principal Deputy Director Martha Williams stated, "the recovery of the bald eagle is one of the most well-known conservation success stories of all time." She adds that they will continue to work with regional partners to ensure the bald eagle recovery's continued success.
Sources: USFWS