As its common name suggests, the rufous night-heron is largely nocturnal, feeding at night and roosting by day in dense vegetation, often in large groups (2) (5) (6) (7). However, during the breeding season it may also feed during daylight hours, to enable it to collect enough food for its chicks (2) (3) (6) (7).
The rufous night-heron is an opportunistic feeder, and its varied diet includes fish, amphibians, insects and their larvae, molluscs, and crustaceans such as crayfish, crabs and shrimps. It also feeds on the eggs and chicks of other birds, and will even take mice and newly hatched sea turtles, as well as feeding on refuse at rubbish dumps (2) (3) (4). The rufous night-heron generally feeds alone (2) (3), but will also occasionally feed in groups (2). This species typically feeds by standing motionless or walking slowly through water before rapidly striking at prey with its beak (2) (3) (4) (6) (7). It has also sometimes been seen wading deeper into water in search of prey (7).
The breeding season of the rufous night-heron is variable and typically depends on rainfall and food availability. However, it usually runs from October to March in Australia, from February to May in the Philippines, and from February to June in Java (2) (3) (5) (7). This species can potentially nest at any time of year given suitable conditions (2) (3) (7).
Although it occasionally nests in solitary pairs, the rufous night-heron more commonly nests in large colonies of up to 3,000 pairs, often with other birds such as cormorants, ibises and other heron species (2) (3) (4) (7). The nest consists of a loose platform of sticks built in a tree or large bush, usually standing in or overhanging water (2) (3) (6) (7). In some locations, such as on islands without trees, the rufous night-heron will also nest on the ground, or even in caves or under rocky overhangs (2) (3) (7), with the nest consisting of nothing more than a few sticks to prevent the eggs rolling away (2) (6) (7).
The rufous night-heron lays two to five pale greenish-blue eggs, with two to three eggs being most common (2) (3) (7). Both adults help incubate the eggs, which hatch after about 21 days (2) (3). The young rufous night-herons start to leave the nest at two to three weeks old, scrambling about among the branches and returning to the nest to be fed (2) (6). The young birds are not able to fly until they are around six to seven weeks old (2) (3) (6).
Each pair of rufous night-herons typically produces a single brood of young each year, but if conditions are favourable a further breeding attempt may occasionally occur (2) (3). This species does not usually start to breed until it develops its full adult plumage at around three years old (2) (3), but younger individuals have sometimes been known to breed while still in their juvenile plumage (2) (4) (7).