Pacific Reef Egret (Dark morph)

62 cm. The species displays an unusual, non-sexual dimorphism, with some members having entirely white plumage and others (the larger portion) being charcoal-grey. The reason for the colour variation or "morph", is unknown, though it is most commonly thought to be related to camouflage. Reef egrets have very short, yellow legs, and the grey variety's throats and chins are marked by a narrow, white stripe. They have brown beaks, gold-yellow coloured eyes and the surrounding areas of their faces are normally of a greenish to yellow cast.