Unusually for weaver birds, species of Foudia are often monogamous. The Mauritius fody generally holds territories of over one hectare exclusively with just one mate (4), although some male Mauritius fodies have been observed with more than one female (3). Breeding between late June and early April (3) (4), both sexes help to build the nest, which is then lined by the female only. Between two and four eggs are laid and incubated by the female, with the male helping to feed the chicks after hatching for two weeks, before they fledge and leave the nest to disperse. At the end of the breeding season, the adults undergo a complete moult. Pairs defend the territory all year, and do not make seasonal migrations (4).
The diet of the Mauritius fody is comprised primarily of invertebrates, but nectar, fruit, seeds and the eggs of birds and geckos are also consumed (5). Some females have even been seen feeding on the eggs of other Mauritius fodies (3).