We provide evidence for cooperative breeding in two endemic parrot species of New Caledonia, the New Caledonian Parakeet (Cyanoramphus saisseti) and the Horned Parakeet (Eunymphicus cornutus). We intensively monitored 11 breeding attempts in two nests of New Caledonian Parakeets over 5 years, and noticed that two males of different size fed the female and the chicks in each nest. During one breeding attempt, the larger male guarded the female and the smaller male tried to copulate with her inside the nest. Genetic analyses showed that males shared paternity. During 17 breeding attempts in 11 Horned Parakeet nests, we observed two pairs sharing a nest on one occasion but we never saw feeding helpers.

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