The Black-crowned Night Heron (Nycticorax nycticorax) is a cosmopolitan species with a wide geographical distribution. It is found on every continent except Antarctica. Significant populations exist in the Americas, Europe, Africa, Asia, and some regions of Oceania, including Australia and parts of the Pacific Islands.

Black-crowned Night Herons typically inhabit a variety of wetland environments. These include freshwater and coastal marshes, rivers, lakes, ponds, mangroves, and swamps. They are often found near slow-moving water or still bodies of water. The species prefers environments that offer abundant vegetation, such as reed beds, trees, and shrubs, which provide cover and nesting sites.

Nycticorax nycticorax is a nocturnal feeder, primarily preying on fish, amphibians, small mammals, crustaceans, and insects. This species plays a crucial role in aquatic ecosystems by regulating prey populations and maintaining ecological balance. It is highly adaptable and can exploit a range of available food resources, which contributes to its widespread distribution and success in various habitats. The presence of humans and urban environments can also influence their habitat choices, with some populations adapting to urban park lakes and rivers.