The Green Heron is a small heron

Heron

The herons are long-legged freshwater and coastal birds in the family Ardeidae. There are 64 recognised species in this family. Some are called "egrets" or "bitterns" instead of "heron"....

 of North

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 and Central America

Central America

Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

. It was long considered conspecific with its sister species the Striated Heron

Striated Heron

The Striated Heron, Butorides striata, also known as Mangrove Heron, Little Heron or Green-backed Heron, is a small heron. Striated Herons are mostly non-migratory and noted for some interesting behavioral traits. Their breeding habitat is small wetlands in the Old World tropics from west Africa to...

 (Butorides striata), and together they were called "Green-backed Heron

Green-backed Heron

"Green-backed Heron" is a collective term for certain herons. Small and compact among herons, these birds often feature green plumage – rare among the Ardeidae –, in particular on the back, wings and scapulars....

". Birds of the nominate subspecies (no matter which taxonomic arrangement is preferred) are extremely rare vagrants to western Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

; individuals from the Pacific coast of North America may similarly stray as far as Hawaii

Hawaii

Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

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The Green Heron is relatively small; adult body length is about 44 cm (17 in).