The dimorphic egret is a species of heron in the family Ardeidae. It is found in Comoros, Kenya, Madagascar, Mayotte, Seychelles, and Tanzania.
Region
Western Indian Ocean islands and East African coast
Typical Environment
Found around Madagascar, the Comoros, Mayotte, Seychelles (including Aldabra), and along coastal Kenya and Tanzania. It favors sheltered marine and brackish habitats such as mangroves, tidal flats, lagoons, reef flats, estuaries, and saltpans. It also uses inland wetlands and rice paddies, especially during seasonal changes. Breeding often occurs in mangrove stands and coastal thickets near feeding areas.
Altitude Range
Sea level to 1500 m
Climate Zone
Tropical
Ease of Keeping
Beginner friendly: 1/5
This egret is notable for its striking plumage dimorphism: birds occur in either a pure white morph or a slate-grey to blackish morph. It closely resembles the Little Egret but is typically darker in the dark morph and favors coastal habitats around Madagascar and neighboring islands. It often feeds by actively stirring the water with its feet to flush prey. Colonies are commonly established in mangroves alongside other herons and egrets.
white and black morph together
Temperament
alert but tolerant, often loosely social
Flight Pattern
strong flier with steady wingbeats and retracted neck
Social Behavior
Typically nests colonially in mangroves or coastal trees, often alongside other herons and egrets. Pairs defend small territories around the nest during breeding. Displays include crest-raising and plume-fanning. Outside breeding, it may forage singly or in small groups, especially at low tide.
Migratory Pattern
Resident
Song Description
Generally quiet away from colonies. At nesting sites it gives harsh croaks, grunts, and rasping calls used in pair interactions and alarm. Calls are short and carry well through mangrove habitats.
Plumage
Two distinct morphs: a white morph with fine ornamental plumes in breeding season, and a dark morph that is slate-grey to blackish with similar texture and plumes. Both morphs show contrasting yellow feet and black legs, with delicate aigrette plumes during courtship.
Diet
Feeds mainly on small fish, prawns and crabs, aquatic insects, and occasional amphibians. It actively stalks in shallow water, using foot-stirring and short darts of the bill to seize prey. It may follow receding tides on reef flats and probe among algae or seagrass for crustaceans.
Preferred Environment
Shallow coastal margins such as tidal creeks, mudflats, and lagoon edges are preferred. It also forages along reef flats and in mangrove channels, and will use flooded fields and wetlands inland when available.
