Heron

Herons Temporal range: Early Oligocene–Holocene 32–0 Ma[1] PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Pelecaniformes
Suborder:	Ardei
Family:	Ardeidae Leach, 1820
Type genus
Ardea Linnaeus, 1758
Genera
18 extant, see text
Global distribution of herons
Synonyms
Cochlearidae

Herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 74 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genus Botaurus are referred to as bitterns, and, together with the zigzag heron, or zigzag bittern, in the monotypic genus Zebrilus, form a monophyletic group within the Ardeidae. Egrets do not form a biologically distinct group from herons, and tend to be named differently because they are mainly white or have decorative plumes in breeding plumage. Herons, by evolutionary adaptation, have long beaks.

The classification of the individual heron/egret species is fraught with difficulty, and no clear consensus exists about the correct placement of many species into either of the two major genera, Ardea and Egretta. Similarly, the relationships of the genera in the family are not completely resolved. However, one species formerly considered to constitute a separate monotypic family, the Cochlearidae or the boat-billed heron, is now regarded as a member of the Ardeidae.

Although herons resemble birds in some other families, such as the storks, ibises, spoonbills, and cranes, they differ from these in flying with their necks retracted, not outstretched. They are also one of the bird groups that have powder down. Some members of this group nest colonially in trees, while others, notably the bitterns, use reed beds. A group of herons has been called a "siege".^[2][3]