The diet of the orange-flanked bush-robin comprises primarily insects, such as beetles, caterpillars, ants and wasps, which it forages for in the undergrowth or may snatch from the air in flight. It will also eat other invertebrates, such as spiders (2), and feeds on fruits and seeds during the non-breeding season (2) (5).
During the breeding season, the male orange-flanked bush-robin arrives at the breeding grounds first (6), and starts defending a territory of roughly fifty metres in radius, mainly through song (7). With the arrival of the females soon after, breeding pairs will form, each occupying a single territory. However, the females may also mate with other males as well as their ‘partner’ (6).
Unlike many birds, the orange-flanked bush-robin nests on the ground rather than in trees. The female constructs a cup-shaped nest from twigs and moss, lined with feathers and grass, which is placed among roots or in a cavity in a tree stump or rotten log (2) (5). Three to seven eggs are laid, which are white and may have a few reddish speckles. The female incubates the eggs for 15 days, and the fledglings will spend a further 15 days in the nest after they have hatched (2).