The yellow-crowned night heron (Nyctanassa violacea) is one of two species of night heron in the genus Nyctanassa. Unlike the black-crowned night heron, which has a worldwide distribution, the yellow-crowned is restricted to the Americas. It is known as the bihoreau violacé in French and the pedrete corona clara or yaboa común in some Spanish-speaking countries.
Taxonomy
The yellow-crowned night heron was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae. He placed it with herons, cranes and egrets in the genus Ardea and coined the binomial name Ardea violacea. Linnaeus based his account on the "crested bittern" that had been described in 1729–1732 by the English naturalist Mark Catesby in the first volume of his The Natural History of Carolina, Florida and the Bahama Islands. Linnaeus specified the type locality as North America, but this has been restricted to the Carolinas following Catesby. The yellow-crowned night heron is now placed together with the extinct Bermuda night heron in the genus Nyctanassa that was introduced in 1887 by the Norwegian born zoologist Leonhard Stejneger. Its congener, the Bermuda night heron (N. carcinocatactes), was endemic to Bermuda, but probably became extinct following human colonization.
Being a heron, the yellow-crowned night heron is related to egrets and bitterns (the family Ardeidae), and, more distantly, to pelicans and ibises (the order Pelecaniformes). The night herons (Nyctanassa and Nycticorax) belong to the Ardeinae subfamily, and are considered to have most recently diverged from the herons of Butorides, Ardeola, and Ardea (e.g., green heron, squacco heron, and great blue heron respectively).
Various classifications recognize either five or six subspecies, but little is known as to how much they are integrated together and how much their geographic range varies. Their body size decreases from north to south, and the shape of their bills varies...
