The Washington eagle – also called the bird of Washington, Washington's eagle, or Washington's sea-eagle – was a very large, brown eagle described by John James Audubon.

It was similar to the juvenile bald eagle and white-tailed sea eagle, but differed in size, details of plumage and morphology, and habits.

Audubon's detractors argued that he had been mistaken about the size, and variously claimed that he had described a "brown eagle" (immature bald eagle), golden eagle, or "sea eagle" (white-tailed eagle).

Audubon writes that he first saw this eagle in 1814, on the upper Mississippi River. His companion, a Canadian hunter, pointed out a large eagle flying past, claiming it to be a "Great Eagle" known to hunters in the Great Lakes area. The man stated that this rare bird sometimes followed hunters in winter, feeding on the entrails of the animals they had killed. In summer, when the lakes were unfrozen, the Great Eagles would take fish from the water in the manner of an osprey. They roosted on rock ledges, where they also raised their young.^{[1]: 58  [2]: 53}

A few years later, Audubon with two companions observed a pair bringing fish to their young on a cliff bordering the Green River in Kentucky. The adults differed in size: the larger one, presumably the mother, had brought a white perch weighing 5 1/2 pounds. One of the men, who lived nearby, knew of the nest site, thinking that it belonged to Brown Eagles. But he reported that he had seen one of them dive for fish in the river, and noted this was unlike the habit of brown and bald eagles, which steal fish from ospreys.

Two years after, Audubon encountered and shot a male near the village of Henderson.^{[1]: 60  [2]: 55} This was the type specimen for his description and measurements. He wrote that he sighted pairs of Washington eagles on two subsequent occasions: over several days in the following January at the Falls of the Ohio; and lastly on 15 November 1821, a few miles upstream from the mouth of the Ohio River.^{[1]: 61  [2]: 56}

Audubon's original watercolor from 1822 was inscribed "Sea Eagle Falco Ossifragus".^[3] In this he may be following the usage of Alexander Wilson.^[4]

George Ord notes:^[4]: 63

It may gratify some of our readers to be informed, that the opinion of Temminck coincides with ours respecting the identity of our Bald and Sea Eagles; but he states that the Falco ossifragus of Gmelin, the Sea Eagle of Latham, is the young of the Falco albicilla, which in its first year so much resembles the yearling of the leucocephalus, that it is very difficult to distinguish them.

To be used: ^{[5][6][7][2][1][3]}