Though widespread in wetlands habitats, the retiring, nocturnal Black-crowned night heron is observed less often than diurnal herons and egrets. night herons forage mostly between dusk and dawn but will also take prey during the day. Night herons are omnivores even taking small nestlings of other birds, During the day, it roosts communally or singly in dense vegetation, where it can often be observed closely.
The Black-crowned Night-Heron is a patient hunter. It will often stand still and just wait for a frog or other small animals to pass by. They may also hunt by vibrating their bills in the water to lure prey into investigating the disturbance.
Young Black-crowned Night-Herons often disgorge their stomach contents when disturbed. This is convenient for ornithologists who want to study their diet.
The adults of this species do not distinguish between their chicks and the chicks of other nests. They will brood chicks which are not their own.
A group of herons has many collective nouns, including a “battery”, “hedge”, “pose”, “rookery”, and “scattering” of herons."