Pacific reef heron

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Eastern Reef Heron
Eastern Reef Egret.jpg
Light morph
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Pelecaniformes
Family: Ardeidae
Genus: Egretta
Species: E. sacra
Binomial name
Egretta sacra
(Gmelin, 1789)

The Eastern Reef Heron (Egretta sacra), also known as the Pacific Reef Egret or Eastern Reef Egret, is a kind of heron. They are found in many areas of Asia including the oceanic region of India, Southeast Asia, Japan, Polynesia, and in Australia, Tasmania and New Zealand.

Pacific Reef Herons are medium-sized herons, reaching 57 to 66 centimeters in length. They have a wingspan of between 90 and 110 centimeters and reach an average weight of 400 grams.

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 color variation or "morph," is unknown, though it is most commonly thought to be related to camouflage.

Dark morph
The two colour morphs, Ko Tao, Thailand

Eastern 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 colored eyes and the surrounding areas of their faces are normally of a greenish to yellow cast.

Their food sources are made up predominantly of varieties of ocean-based fish, crustaceans and molluscs.

The species lay clutches of eggs year round in colonies in the jungle, between palms and mangroves or in cavities of old buildings. Two to three paled greenish-blue eggs are laid in nests constructed from branches and blossoms. Males and females share brooding tasks. They normally have a 28-day brood period. After chicks are hatched, parents provide approximately 5 weeks of support.

Mooloolabah, Australia


References

Juvenile dark morph, Coral Bay, WA
  • BirdLife International (2008). "Egretta sacra". IUCN Red List of Threatened Species. Version 2008. International Union for Conservation of Nature. Retrieved 9 February 2009. Database entry includes justification for why this species is of least concern.
  • Riffreiher from the German-language Wikipedia. Retrieved April 6, 2006, and containing the internal reference:
  • 1974: Bruce Campbell "The Dictionary of Birds in Colour", George Rainbird Ltd., London.