SPECIES

Bald Eagle Haliaeetus leucocephalus Scientific name definitions

David A. Buehler
Version: 2.0 — Published October 7, 2022

Distribution

Introduction

Breeding Range

Breeds near aquatic ecosystems (e.g., rivers, lakes, reservoirs, and coastal bays) with forested shorelines or cliffs in much of North America. In Alaska, breeds from the southern Brooks Range to coastal areas of southeastern Alaska and across to Aleutian Islands (80). In Canada, the breeding range extends to northern Yukon and southern British Columbia east to Labrador, Newfoundland, and Nova Scotia, with large populations in coastal British Columbia and southern Quebec (81, 82, 83, 84, 85, 86), and uncommon breeder in mainland portion of Nunavut, north to Kugluktuk area (87). Also breeds in every state in the contiguous United States, with large populations scattered along the entire Atlantic Coast, in the Great Lakes (Michigan, Wisconsin, and Minnesota), and the Pacific Northwest (From northwestern California through western Washington. Very small numbers breed in Mexico at Magdalena Bay, Baja California Sur (< 10 pairs), southern Sonora and Chihuahua (88, 89).

Overwintering Range

Winters predominantly in the contiguous United States, coastal and southern portions of Canada, and southeastern Alaska (90), favoring aquatic areas with some open water for foraging. There are a few reports of adults wintering in the interior of Alaska, along the Tanana River near Fairbanks, where open water is present year round (91), and a small number winter in northern Mexico along the Gulf of Mexico, the Gulf of California, Magdalena Bay in Baja California Sur, and river systems in Sonora and Chihuahua (92). The majority of the wintering population is found along major midwestern river systems, Chesapeake Bay, southeastern U.S. coast, Florida, Pacific Northwest river valleys, the Klamath Basin of Oregon and California, and reservoirs and rivers of the Intermountain West (90).

Other Records

Rather few extralimital records. In Mexico, there are records south to Jalisco, the state of Mexico, and northern Veracruz (eBird). Bald Eagle is a vagrant (October–March) in the Caribbean, with 5 records in western Cuba (93, 94) and 7 records in the Bahamas (Abaco, Grand Bahama, Exumas; 94); there are single records in Puerto Rico and St. John (U.S. Virgin Islands) (95). There are 5 records from Bermuda (96, 97, eBird). Casual along the Arctic coast of northeastern Siberia (80). Vagrant in Japan, where there is a July 2001 record (98), and an adult was photographed on Nemuro peninsula (Hokkaido, Japan), where present for at least 3 weeks in winter 2021 (eBird: S81507548). Single juveniles have been recorded in Ireland (November 1987) and Northern Ireland (January 1973) (99); there are 2 unaccepted reports from Britain (see 99). A specimen from Sweden, collected in 1850 has been reported as a Bald Eagle (8), but its identity was considered questionable (1).

Historical Changes to the Distribution

Although there were dramatic changes in population size during the 1900s, the current breeding range is likely similar to the historic breeding range (pre-1900). Prior to the settlement of North America by Europeans, the Bald Eagle was common and probably nested throughout the continental United States, except possibly Rhode Island, West Virginia, and Vermont (100, 101); its range as reported in 1906 (102) was very similar to its current distribution. Due to persecution, habitat loss, and the use of DDT (after 1947), the species' range contracted dramatically, especially in the lower 48 states. As a result, by the 1970s, the Bald Eagle was extirpated from most breeding areas in the United States east of the Rocky Mountains (except for the northern Great Lakes), as well as Utah, Nevada, and southern California. The banning of DDT in 1972 and decreased persecution by humans led to a dramatic increase in population and range starting around 1980 (103, 104, 105).

Perhaps exemplary of changes in the contiguous United States as a whole is the oscillation in the Chesapeake Bay population (which is in Maryland, Delaware and Virginia), which as been monitored since the 1890s. The estimated population along Chesapeake Bay, prior to European settlement, was 3,000–8,000 pairs (106, 107). The first actual census in the 1930s found only about 600 pairs (108). The nadir was 80–90 pairs in 1970, but by 2001 the population had rebounded to approximately 600 pairs (105), and as of 2019, the Chesapeake Bay population was estimated at 2,474 pairs (109).

Distribution of the Bald Eagle - Range Map
Enlarge
  • Year-round
  • Migration
  • Breeding
  • Non-Breeding
Distribution of the Bald Eagle
Bald Eagle, Abundance map
The Cornell Lab logo
Data provided by eBird

Bald Eagle

Haliaeetus leucocephalus

Abundance

Relative abundance is depicted for each season along a color gradient from a light color indicating lower relative abundance to a dark color indicating a higher relative abundance. Relative abundance is the estimated average count of individuals detected by an eBirder during a 1 hour, 1 kilometer traveling checklist at the optimal time of day for each species.   Learn more about this data

Relative abundance
Year-round
0.01
0.11
0.67
Breeding season
May 24 - Jul 13
0.01
0.11
0.67
Non-breeding season
Dec 21 - Feb 1
0.01
0.11
0.67
Pre-breeding migratory season
Feb 15 - May 17
0.01
0.11
0.67
Post-breeding migratory season
Jul 20 - Dec 14
0.01
0.11
0.67
Note: Seasonal ranges overlap and are stacked in the order above; view full range in season maps.
Seasons timeline
Learn more about seasons

Recommended Citation

Buehler, D. A. (2022). Bald Eagle (Haliaeetus leucocephalus), version 2.0. In Birds of the World (P. G. Rodewald and S. G. Mlodinow, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.baleag.02