The red-eared firetail is rare in captivity, being neither recommended nor generally permitted, as they require expertise and a large specialised environment to maintain their secretive habits; however, the observations in avicultural literature have supported and contributed to knowledge of its behaviour.

[2][a] The description was published in the zoology volume of Dumont d'Urville's account of the expedition aboard the Astrolabe, based on a specimen that Quoy and Gaimard had collected at King George Sound.

[2][4] Their publication preceded the entry as Estrelda oculea in John Gould's Birds of Australia (1848), this later description making an unnecessary emendation to the spelling of the epithet oculata.

Similar names with variant spellings were given for the districts of King George Sound, Darling Range, and Perth by Serventy and Whittell in their mid-twentieth century A Handbook of the Birds of Western Australia (with the exception of the Kimberley Division) (1948).

[17] The red-eared firetail is a small grass-finch with black-barred and white-spotted plumage, distinguished by its scarlet bill, black mask, and bright crimson red patch behind the eye and at the rump.

The black at the eyes and lores is absent or nearly so; the distinct red of the upper tail coverts and rump is duller, and underparts are lighter, buff coloured, and mottled rather than spotted.

The juvenile's bill begins as a brownish black colour, becoming scarlet between fourteen and twenty two days after fledging, with blue luminous tubercules are evident at the gape.

The species is uncommon to scarce within its range, although it may be locally common in undisturbed locations, which is typically heavy forests and dense heaths around gullies, rivers, and swamps.

[13] From the southern coast the species occurs as far north as Cape Naturaliste, Bridgetown, Lake Muir, the Stirling Range, Gairdner River (Calyerup) and the Ravensthorpe Range, and is present off the coast at Bald and Coffin Islands near the city of Albany.,[24] The eastern extent of the population at the Esperance Plains region occurs at Cape Arid National Park, and at offshore outcrops of the Recherche Archipelago, such as Middle and Woody Islands.

[25] Serventy noted the species had disappeared from areas near Perth and Pinjarra by the mid-twentieth century, perhaps from the Swan Coastal Plain altogether, though it had persisted at gullies around Mundaring Weir in the Darling Range.

[14] The Records (1991) of the Western Australian Museum gave a northernmost location of Glen Forrest in the Darling Range to an area near North Bannister and Mount Saddleback, and confirmed their continued absence from the Swan Coastal plain.

[26] Carter had earlier given his observations between Albany and Cape Naturaliste, and noted it was common at springs on limestone hills near Margaret River, Western Australia; he considered a specimen he shot in a karri tree as outside its usual habitat of the dense understorey.

[28] Marginal habitat defined by swamp peppermint (Agonis linearifolia), in association with wiry wattle (Acacia extensa), false baeckea (Astartea fascicularis), and karri hazel, is also favoured by the species.

The occurrence at dune vegetation systems records a complex of rushes and sedges with many species of shrubs, including Olearia axillaris, Boronia alata and Acacia decipiens, in low heathland dominated by Jacksonia horrida.

Surveys of earlier study sites in the Darling Range found greater numbers in habitat closer to the Wungong Dam than along its tributaries and surrounding valleys.

Casual observations are frequently made close to the carparks at Little Beach, Two Peoples Bay and Porongurup nature reserves, and amongst the heath of the headland at Cape Naturaliste.

The reclusive behaviour is not displayed outside its native habitat and the species has been observed feeding with western rosellas (Platycercus icterotis) and splendid fairy wrens (Malurus splendens) at parkland and gardens.

There are records of the species being tamely and regularly drawn to seed at tourist sites like Cape Naturaliste; and, it was casually observed in 2010 with western rosella and rock parrots (Neophema petrophila) at Nornalup.

[11] The first study of the species in the field was by John Gilbert, whose notes were printed verbatim in Gould's handbook (1865) and cited by North (1914)[19] and others; the accuracy of his reports has been verified in subsequent research.

The northern study site in the Darling Range noted the birds fed on seeds from species Lepidosperma angustatum and Bossiaea (pea family Papilionaceae), and the fruit from the karri hazel.

[11] Specimens in captivity will eat green leaf matter, supported by an observation of probable feeding on clover leaves in a maintained lawn at Mundaring Reservoir.

[11] The song of captive species was reported, when courting or alone, as beginning with a whistle like a flute, a note extending over four loud pulses, and ending in repeated grasping sounds.

[11] Courtship and breeding habits recorded at Immelmann's site in 1960 are supported by later observations and cited in ornithological literature (Storr and Johnstone, 2004; Forshaw and Shephard, 2012; et al.).

The male selects a nesting site and presents an overt display—presumably to entice a female—of an inflated pose and issues a rendition of its identity call, interspersed with hopping movements about the branches.

The male may continue these gestures for up to 45 minutes, perhaps utilising a length of grass (200–450 mm) that appears to be pierced but is actually held at the point of the bill by a fibre pulled from the base of the stalk.

The male abandons his performance when a female responds by investigating the display area, and retires to the precise location he has proposed; at this position, usually a discreet fork in the branches, he drops his grass stem prop and utters his nest site call.

[31] The nests of the previous season observed at Cape Leeuwin by Carter (1921), where local boys said they appeared every year, are described as slightly domed structures composed of fibre and fine grasses.

[19] The red-eared firetail is regarded as an attractive but difficult bird in aviculture: they are rare and expensive, require permits that are restricted to specific research purposes, and remain mostly hidden in large and elaborate aviaries that simulate their habitat.

Aviaries that reproduce a suitable habitat with an understorey of grasses and shrubs beneath a canopy of trees (species Kunzea, Callistemon, Grevillea or Melaleuca) have been successful in accommodating breeding pairs.

The few successful programs include those in New South Wales published by David Myers and the rearing of seven young from two pairs in a television feature on Burke's Backyard; other captive breeding is recorded in the states of Victoria and Western Australia.