 Like all New World warblers , the red warbler is an insectivore . It gleans primarily in understory shrubs . Breeding typically occurs between February and May . The female lays three or four eggs in a domed nest , which she builds on the ground . Though she alone incubates the eggs , both sexes feed the young and remove fecal sacs from the nest . The young fledge within 10 – 11 days of hatching . 
