A large wading bird with all-white plumage; long black legs and feet; a long neck; and a long, straight, pointed, yellow bill; in breeding plumage, long white plumes extend from back beyond end of tail; average length 99 cm, wingspan 130 cm.
For a comprehensive review of the conservation status, habitat use, and ecology of this and other Montana bird species, please see Marks et al. 2016, Birds of Montana.
Differs from most other white herons in larger size (averages 23 cm longer than Reddish Egret, 38 cm longer than Snowy Egret), unicolored yellowish bill, and all-black legs and feet. Differs from the white form of the Great Blue Heron in having black legs and feet (versus yellowish).