Abstract. We provide information on the onset of incubation, the involvement of males and females in incubation, and on the hatching pattern in the Rufous Vanga Schetba rufa of Madagascar. Rufous Vangas breed cooperatively with one to four one-year-old and/or adult auxiliary males. Large amounts of time were spent in incubation from the date the first-egg was laid. Breeding male Rufous Vangas took a much greater share of incubation during the laying period than did females, but males and females took almost equal shares during the incubation period. Females spent more time brooding their chicks than did males, however, males contributed more in terms of provisioning young chicks than did females. While the hatching pattern varied from perfectly asynchronous to perfectly synchronous, the fledging pattern was generally synchronous with all chicks in a given brood fledging on the same day. The nest failure hypothesis cannot explain the adaptive significance of early commencement of incubation in this species, because the incubation pattern was not a reliable predictor of the hatching pattern. As the daily
RufousVangas commence incubation on the day on which the first egg is laid in order to regulate egg temperature and to increase the hatchability of first-laid eggs. Males may take charge of incubation during the laying period because females must spend considerable time foraging in order to produce eggs. Dominant males, in cooperatively breeding groups, may spend considerable time incubating, despite the risk of cuckoldry by auxiliary males, in order to raise the rate of hatchability.