Ardea (genus)

Ardea
	Gray heron ( ardea cinerea )
Systematics
Class :	Birds (aves)
Order :	Pelecaniformes
Family :	Herons (Ardeidae)
Subfamily :	Day heron (ardeinae)
Genre :	Ardea
Scientific name
	Ardea
	Linnaeus , 1758

Ardea is a genus of herons that belong to the subfamily of the day heron . Carl von Linné called them Ardea (Great Heron) because most of the species of this genus reach a body size of over 80 centimeters.

The species of the genus Ardea are distributed almost worldwide and are only absent in the very cold regions of the world. Their habitat are wetlands. Their diet consists mainly of fish, frogs and other small animals that are bound to the water in their way of life. Most species breed in colonies and build their nests in trees. The northern species such as the gray heron , the great blue heron and the purple heron migrate south in winter. In the case of the gray heron and great blue heron, however, this migratory movement only takes place in areas where the water freezes.

The Ardea species are characterized by a long, spear-like beak, long necks and long legs. They acquire their prey by either waiting motionless for prey to get within reach, or by moving very slowly through the shallow water before grabbing their prey in one swift movement. Ardea species have a slow, steady flight in which the neck is turned back. This distinguishes them from storks , cranes and spoonbills , which fly with their necks stretched out.

Systematics

Some of the species are very closely related. The gray heron, the Canadian heron and the coconut heron are all representatives of a super species . The classification of the great egret in this genus is controversial. It is occasionally assigned to the genus Egretta or Casmerodius . However, the species has a lot in common with the Ardea species and differs very much, especially in its plumage.