It is primarily nocturnal and is observed in a broad range of habitats, including forests, meadows, shores, reefs, marshes, grasslands, and swamps.

The nankeen night heron has a stable population size, and is classified as a species of least concern by the International Union for Conservation of Nature (IUCN).

[1] The nankeen night heron was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae.

[2] Gmelin based his description on the "Caledonian night heron" that had been described in 1875 by the English ornithologist John Latham in his multi-volume work A General Synopsis of Birds.

The heron had been observed in September 1774 on the island of New Caledonia during Captain James Cook's second voyage to the Pacific Ocean.

The naturalist Johann Reinhold Forster, who had accompanied Cook on the voyage, provided Latham with a description of the species.

[6][7] The term nankeen in the common name of the species is defined as 'a type of pale-yellow cotton cloth, originally from China' in the Cambridge Dictionary.

[9] Juvenile nankeen night herons are quite different in appearance compared to adults, with the top of their head and their nape being a black-brown colour and streaked with beige.

[10] The tail of juveniles is rufous-brown, the legs and feet are lime-green to olive-grey, and the bill is a dull olive-yellow colour with black on the tip.

[9] Nankeen night heron chicks are covered with dark brown down feather on their back and white on the undersides.

[10] Nankeen night heron chicks are described to beg with a kak-kakkak call in their first two weeks, in order to obtain the attention of their parents for feeding.

[9] After leaving their nest, during the period when they are still flightless, young nankeen night herons utter a noisy high-pitched screech when alarmed.

[13] The nankeen night heron is resident in a wide range of habitats, which includes grasslands, meadows, forests, lagoons, beaches, reefs, marshes, shores, wetlands, and swamps.

[14] The nankeen night heron is mainly nocturnal, and thus roosts during the daytime in dense cover of trees, bushes, and reeds.

[10] In urban areas, the nankeen night heron favours nesting and roosting in trees such as cypresses and pines.

[13] Adult nankeen night herons in Australia are observed as partially migratory, moving during winter and major events such as flood and rainfall.

[14] When facing threats, male nankeen night herons will stand fully erect and make rasping sounds or snap its bill, signalling aggressive intentions.

[10] Its other prey include frogs, lizards, mice, as well as insects such as crickets, water beetles, ants, wasps, caterpillars, and dragonfly larvae.

The IUCN Red List states that for these reasons, the nankeen night heron is evaluated as a species of least concern.