Golden Eagle Hunting A Sika Deer, Lazovsky District, Primorsky Krai, Russia

Aquila chrysaetos japonica Severtzov, 1888 – the common name is the Japanese Golden Eagle. This race is found in northern Japan (the islands of Honshu, Hokkaido and discontinuously in Kyushu) and undefined parts of Korea. Male wing length is from 58 to 59.5 cm (23 to 23.4 in), averaging 59 cm (23 in), and female wing length is from 62 to 64.5 cm (24 to 25.4 in), averaging 63 cm (25 in). No range of body weights are known but males will weigh approximately 2.5 kg (5.5 lb) and females 3.25 kg (7.2 lb). This is by far the smallest bodied subspecies. It also the darkest with even adults being a slaty-grayish black on the back and crown and juveniles being similar but with darker black plumage contrasting with brownish color and white scaling on the wings, flank and tail. This race has bright rufous nape feathers that are quite loose and long. Adult Japanese Golden Eagles often maintain extensive white mottling on the inner-webs of the tail that tend to be more typical of juvenile eagles in other races.
- Aquila chrysaetos canadensis (Linnaeus, 1758) – Commonly known as the American Golden Eagle. Occupies the species’ entire range in North America, which compromises the great majority of Alaska, western Canada and the Western United States. The species is found breeding occasionally in all Canadian providences but for Nova Scotia. It is currently absent in the Eastern United States as breeding species east of a line from North Dakota down through westernmost Nebraska and Oklahoma to West Texas. The southern limits of its range are in central Mexico, from the Guadalajara area in the west to the Tampico area in the east. It is the subspecies with the largest breeding range and is probably the most numerous subspecies, especially if A. c. kamtschatica is included. Male wing length is from 59.1 to 64 cm (23.3 to 25 in), averaging 61 cm (24 in), and female wing length is from 60.1 to 67.4 cm (23.7 to 26.5 in), averaging 65 cm (26 in). The average wingspan in both sexes is about 2.04 m (6 ft 8 in). Males weigh from 2.5 to 4.47 kg (5.5 to 9.9 lb), averaging 3.48 kg (7.7 lb), and females typically weigh from 3.6 to 6.4 kg (7.9 to 14 lb), averaging 4.91 kg (10.8 lb). The race does not appear to follow Bergmann’s rule (the rule that widely distributed organisms are larger-bodied further away from the Equator), as specimens of both sexes from Idaho had a mean weight of 4.22 kg (9.3 lb) and where slightly heavier than those from Alaska, with a mean weight of 3.76 kg (8.3 lb). It is medium-sized, being generally intermediate in size between the nominate and A. c. homeyeri but with much overlap. It is blackish to dark brown on the back. The long feathers of nape and top-neck are rusty-reddish and slightly narrower and darker than in the nominate race.
- Aquila chrysaetos kamtschatica Severtzov, 1888 – sometimes is referred to as the Siberian Golden Eagle or the Kamchatka Golden Eagle. This race ranges from Western Siberia (where overlap with A. c. chrysaetos is probable), across most of Russia, including the Altay (spilling over into Northern Mongolia), to the Kamchatka Peninsula and the Anadyrsky District. This subspecies is often included in A. c. canadensis. Male wing length is from 61.8 to 70.5 cm (24.3 to 27.8 in), averaging 64 cm (25 in), and female wing length is from 65 to 72 cm (26 to 28 in), averaging 69 cm (27 in). No weights are known in this race. The coloration of these eagles is almost exactly the same as in A. c. canadensis. The main difference is that this race is much larger in size, being is nearly the equal of A. c. daphanea going on wing-length.
The larger Middle Pleistocene Golden Eagles of France (and possibly elsewhere) are referred to a paleosubspecies Aquila chrysaetos bonifacti, and the huge specimens of the Late Pleistocene of Liko Cave (Crete) have been named Aquila chrysaetos simurgh. Similarly, an ancestral Golden Eagle, with a heavier, broader skull, larger wings and shorter legs when compared to modern birds, has been found in the La Brea Tar Pits of southern California.