The common waxbill Estrilda astrild, is a small passerine bird that belongs to the Estrildidae family, a subfamily within the Passeridae. It is native to sub-Saharan Africa but has been introduced to many other regions of the world, including Mauritius. It measures between 11 and 13 centimeters and has a wingspan of 12 to 14 centimeters. The common waxbill gets its name from the bright red bill of the adult – resembling the colour of sealing wax. The bird bears a red stripe through the eye while the rest of its plumage is mostly grey-brown with thin dark brown bars, with the exception of a bright pink patch in the centre of its belly. Females are slightly paler than males and their pink-reddish underparts less striking, as are juveniles, which also have black bills. The species can be heard twittering and buzzing and has a distinctive high-pitched flight call.
Common waxbills inhabit tall grasses, grassy fields, swamps and marshes, savannas, and abandoned cultivation areas. The species feeds mainly on seeds, clinging to the stems with their claws while picking from the flower heads or searching for fallen seeds on the ground. Its diet is occasionally complemented by insects including ants, termites and moths particularly during the breeding season. A gregarious species, common waxbills forage in flocks and are often seen in large flocks outside of the breeding season.
In courtship, an elaborate display is carried out by males. They carry a slender grass stem, fly to perch and hold the stem looking upwards while fluffing their belly and flanking their wings. They tilt their body away from females, thereby exposing their underparts while angling their tail and heads towards her and move up and down by flexing their legs. After a few movements, they sing. Females respond with the same movements without song.
The nest is spherical and consist of crisscrossed grass stems with an entrance tube pointing downwards on one side. It is usually built low down in vegetation in a cavity. The female lays four to seven white eggs, which are incubated by both parents for 11 to 13 days. Fledgling occurs 17 to 21 days after hatching.
The common waxbill is listed as ‘Least Concern’ in the IUCN Red List of Threatened Species. Given the large range of the species, it is currently not considered threatened.
Males may build a rudimentary second nest on top of the primary nest for themselves