Great Blue Egret

English: Great blue heron seen at the entrance to Loxahatchee National Wildlife Refuge in West Palm Beach, Florida, USA. (Photo credit: Wikipedia)

Feeding Great Blue Heron (Ardea herodias) chicks , San Francisco, California (Photo credit: Wikipedia)

Approximate range/distribution map of the Great Blue Heron (Ardea herodias). In keeping with WikiProject: Birds guidelines, yellow indicates the summer-only range, blue indicates the winter-only range, green indicates the year-round range, and orange indicates areas through which the species will pass during migratory activity. (Photo credit: Wikipedia)

http://en.wikipedia.org/wiki/Great_Blue_Heron

It has head-to-tail length of 91–137 cm (36–54 in), a wingspan of 167–201 cm (66–79 in), a height of 115–138 cm (45–54 in), and a weight of 2.1–3.6 kg (4.6–7.9 lb).[4][5][6] Notable features include slaty flight feathers, red-brown thighs, and a paired red-brown and black stripe up the flanks; the neck is rusty-gray, with black and white streaking down the front; the head is paler, with a nearly white face, and a pair of black plumes running from just above the eye to the back of the head. The feathers on the lower neck are long and plume-like; it also has plumes on the lower back at the start of the breeding season. The bill is dull yellowish, becoming orange briefly at the start of the breeding season, and the lower legs gray, also becoming orangey at the start of the breeding season. Immature birds are duller in color, with a dull blackish-gray crown, and the flank pattern only weakly defined; they have no plumes, and the bill is dull gray-yellow.[3][7][8] Among standard measurements, the wing chord is 43–49.2 cm (17–19.4 in), the tail is 15.2–19.5 cm (6.0–7.7 in), the culmen is 12.3–15.2 cm (4.8–6.0 in) and the tarsus is 15.7–21 cm (6.2–8.3 in).[9][10]

The call is a harsh croak. The heron is most vocal during the breeding season, but will call occasionally at any time of the year in territorial disputes or if disturbed.
The “Great White Heron” could be confused with Great Egret but is larger, with yellow legs as opposed to the Great Egret’s black legs. The Reddish Egret and Little Blue Heron could be mistaken for the Great Blue Heron, but are much smaller, and lack white on the head and yellow in the bill. In the southern reaches of its range, the Great Blue sometimes overlaps in range with the closely related and similarly sized Cocoi Heron. The Cocoi is distinguished by a striking white neck and solid black crown, but the duller juveniles are more easily confused. More superficially similar is the slightly smaller Grey Heron, which may sometimes vagrate to the Northern coasts of North America. The Grey (which occupies the same ecological niche in Eurasia as the Great Blue Heron) has very similar plumage but has a solidly soft-gray neck. Erroneously, the Great Blue Heron is sometimes referred to as a “crane”.