Black-crowned night heron
The black-crowned night heron is a globally distributed bird found in regions across Europe, Asia, and the Americas. This medium-sized heron, measuring 23 to 26 inches long and weighing between 25 and 35 ounces, is recognizable by its distinct black crown and long, slender white plumes. Despite its name, the black-crowned night heron often hunts during the day, utilizing various techniques to catch prey such as fish, frogs, and insects in wetland habitats. They thrive in areas with dense vegetation near water bodies, including rivers, ponds, and marshes, and sometimes adapt to coastal environments.
These herons are social animals, roosting in large colonies, and they exhibit territorial behavior during breeding seasons, which occur twice a year. Males display vibrant coloration in their feet during this time and help build nests where females lay three to four blue-green eggs. Both parents share incubation duties, and after hatching, the chicks depend on their parents for food and care for several weeks. While young herons face threats from predators like hawks and raccoons, the black-crowned night heron is currently not considered a threatened species, with a lifespan of up to 20 years.
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Black-crowned night heron
The black-crowned night heron can be found throughout the world in Europe, Asia, and North and South America. The black-crowned night heron may be smaller than some of its larger family members, but it is still an efficient hunter in wetland habitats. Whether it stalks slowly through the water, swims and dives, or feeds on land, this bird snatches its prey quickly and swallows it headfirst.
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Pelecaniformes
Family: Ardeidae
Genus: Nycticorax
Species: Nycticorax
Black-crowned night herons are named for the caps of black feathers on the tops of their heads. From these black caps grow several long, slender, white plumes. A narrow, white band runs across the forehead and above each red eye. The feathers on their backs are black and green. The rest of their 23 to 26 inch (58 to 66 centimeter) bodies are white or cream, while their wings are gray. They weigh between 25 and 35 ounces (708 and 992 grams).
Although they are named night herons, these birds feed during the day as well. During breeding season, when they need to feed their young, parents often do hunt during the nighttime hours. At other times in the year they hunt during the early morning and evening hours and then rest during the day. The herons may either stalk slowly through the shallow water or swim and dive to catch fish, frogs, and aquatic insects and their larvae. Hunting techniques may also include spreading their wings over their heads to shade the water so the herons can see prey more clearly. They may also drop food scraps on the water to attract fish. On land, small mammals, spiders, bird's eggs and birds, including other heron chicks, may all feed the appetites of the herons.
Dense vegetation along river banks, ponds, streams, swamps, and marshes is one of the best places to find these night herons. Some may also live near saltwater in coastal marshes and lagoons or tidal creeks. The birds roost in colonies which may contain several hundred members. The coming of winter causes herons in the northern parts of the birds' range, particularly in North America and Asia, to migrate south.
Breeding occurs twice a year, between February and March, and again between June and July. Although the males live peacefully beside each other during the rest of the year, during this time they become territorial. Any heron other than a male's mate which trespasses into a male's territory is chased away with hissing and other defensive behavior. During the breeding season, the male's green feet turn bright yellow or red. The female weaves a nest from the twigs the male brings her. She may select a nest site in a bush or reedbed near the water or in a tree as high as 150 feet (45 meters) above the ground. In her nest, the female lays three to four blue-green eggs. She lays one egg every two days. Both male and female incubate the eggs, each of which takes 24 to 26 days to hatch. The chicks which hatch first usually get more food and are more likely to survive if food is scarce. After three weeks of eating fish from their parents, the chicks are able to leave the nest and climb about the trees nearby. They continue to need their parents until they are six weeks old and can fly. Mating for the first time occurs when they are two or three years old.
The predators of the black-crowned night heron include hawks and eagles. The young are especially vulnerable, and eggs may be eaten by raccoons. The lifespan of black-crowned night heron is 20 years. The black-crowned heron is not a threatened species.
Bibliography
Polan, Jason. “Black-Crowned Night-Heron - Audubon Field Guide.” National Audubon Society, 2024, www.audubon.org/field-guide/bird/black-crowned-night-heron. Accessed 24 Mar. 2024.
The Cornell Lab of Ornithology. “Black-Crowned Night Heron Overview.” All About Birds, 2024, www.allaboutbirds.org/guide/Black-crowned‗Night‗Heron/overview. Accessed 24 Mar. 2024.