Species: Black-crowned night heron
Scientific name: Nycticorax nycticorax
Nicknames: Night heron
Claim to fame: Although great blue herons are the best known heron species here in the Ozarks, it’s smaller and less-conspicuous cousin – the black-crowned night heron – has a much broader range. Black-crowned night herons can be found on five continents – making them the most widespread heron species in the world. However, due to their primarily nocturnal habits and a size that’s smaller than their great blue heron cousins, black-crowned night herons are seen infrequently by much of the nature-viewing public over a large portion of their range – including here in Missouri.
Species status: Due to its perception as a pest of sportfish populations (a sometimes undeserved reputation), hunting pressure, and wetland habitat degradation; black-crowned night heron populations experienced decline over parts of their range in the 19th and 20th centuries. However, recent conservation efforts have stabilized the bird’s population in most parts of its range.
First discovered: The first scientific description of the black-crowned night heron was written by the famed naturalist Carl Linnaeus in 1758.
Family matters: Black-crowned night herons belong to the Ardeidae family of birds; a group more commonly known as the herons. Most members of this family are wading birds with longer, spear-like beaks used for catching small fish and other aquatic creatures.
Length: 23 to 28 inches (wingspan, 44 inches)
Diet: The bulk of a black-crowned night heron’s diet consists of aquatic invertebrates, fish, amphibians, lizards, snakes and small rodents.
Weight: Between 1.5 and two pounds
Distinguishing characteristics: Black-crowned night herons have short necks and thick black bills. They have black caps and backs, gray wings and whitish underbellies. Black-crowned night herons have been known to live more than to 20 years, but 5-10 years is probably a much more accurate estimate for the majority of the species. These birds hunt mainly at night – hence the name “night heron.” They have a coarse, croak-like call.
Life span: Information not available
Habitat: Most colonies of black-crowned night herons are associated with large wetlands. These wetland habitats usually take the form of swamps, streams, rivers, marshes, mud flats or marshy edges of lakes that have become overgrown with vegetation.
Life cycle: Black-crown night herons are primarily summer residents of Missouri. Courtship and breeding take place in spring. Like several other types of herons, black-crowned night herons nest in colonies; as many as a dozen nests have been found in larger trees. Nests consist of a platform of sticks and are often used more than one year. The average clutch contains between three and five eggs. Eggs hatch in 24-26 days. Both parents brood the young. The young fledge in 42-49 days and the colonies disperse in middle to late summer. During winter, black-crowned night herons migrate to the Gulf Coast region.