Nycticorax nycticorax or commonly known as Black-crowned Night Heron is a moderate size for a heron species measuring about 60 cm in length. This bird can be found in mangroves, mudflats, river edges and swamps (Strange & Jeyarajasingam, 1993). It is an opportunistic predator, with a varied diet that includes small fishes, crabs, crayfishes, snakes, amphibians, small rodents, the chicks of other birds, insects and sometimes plants matter.

The black-crowned night heron is a three-coloured adult with a black crown and back, pearly grey wings and white underparts. They have thick necks, large, flat heads, and a heavy, pointed all-black bill for adult whereas yellow-and-black bill for the juvenile. Its legs are short that it barely reaches the end of the tail during flight and the wings are broad and rounded. The juvenile has dark brown plumage with large white spots on the wings and blurry streaks on the underparts but as they grow, their plumage becomes more solidly dark above and pale below.