|Black-Crowned Night Heron
The black-crowned night heron is found across North America from Washington through Quebec, south through coastal Mexico, as well as locally in Central America and the Caribbean.
The night heron has a stocky body, with a comparatively short neck and legs. The adult has distinctive coloring, with black cap, upper back and scapulars, gray wings, rump and tail, and white to pale gray under parts. The bill is stout and black, and the eyes are red. For most of the year, the legs of the adult are yellow-green, but by the height of the breeding season, they have turned pink.
Black-crowned night herons are presumed to be monogamous. Pair formations are signaled by males becoming aggressive and performing Snap Displays, in which they walk around in a crouched position, head lowered, snapping their mandibles together or grasping a twig. Eggs are laid at two day intervals, beginning four to five days after pair formation. Incubation, which lasts 24-26 days, is carried out by both adults. The clutch size is three to five eggs. The eggs are greenest on the first day and fade to pale blue or green after that.
The black-crowned night heron is an opportunistic feeder. Its diet consists mainly of fish, though it is frequently rounded out by other items such as leeches, earthworms, aquatic and terrestrial insects. It also eats crayfish, mussels, squid, amphibians, lizards, snakes, rodents, birds, eggs, carrion, plant materials, and garbage.
Black-crowned night herons are social at all times of the year, associating with other species of herons frequently. In the winter, it roosts communally. It is a migrating species. This bird’s call is most often given in flight or from a perch. The fact that this night heron feeds throughout the night means that it avoids competition with day herons which use the same habitat.
Sources: IUCN 2009. IUCN Red List of Threatened Species. Version 2009.2. <www.iucnredlist.org>. 2009, December.
Ivory, A. 2002. "Nycticorax nycticorax" (On-line), Animal Diversity Web. Accessed December 03, 2009 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Nycticorax_nycticorax.html.