Western Reef Herons occur in pale and dark plumage forms; the dark form is marked by a white throat. They hunt along coasts and estuaries.
The dark form is deep, bluish gray with a sharply defined white throat. The size of the white wing patch and the white areas around the face vary among individuals.
In shallow water it may wait for fish, then thrust its head and bill forward quickly. It also walks after fish, and takes crustaceans such as crabs along the coast.
It builds nests of twigs and branches in trees, bushes, cliff ledges or cavities, and sometimes on the ground on uninhabited islands. Nests may be spaced apart or grouped with other waterbirds.
In breeding plumage, fine elongated feathers develop on the breast and back, with two long feathers on the back of the head.
An extinction-risk assessment has not been added yet.