Résumé
Knowledge of the recruitment potential, as well as post-recruitment survival, between different reef habitats, would improve the management of target species and conservation of reef ecosystems. Many coral reefs have been subjected to, and continue to suffer from, habitat degradation due to both natural and anthropogenic stress. However, the effects of habitat degradation on larval recruitment potential and on the survival of settled recruits are currently not known. We aimed to distinguish between these two processes by simultaneously measuring survival and recruitment of vertebrate and invertebrate larvae across habitats differing in their percentage of coral cover (healthy vs dead: 50 % vs 12 % coral cover) with a 100 % sand habitat as a control. Recruitment and survival were monitored after 10, 20, 40 and 80 days on atolls in French Polynesia. Lower recruitment was identified for multiple molluscan, gastropod and sponge species in the control sand habitat, possibly reflecting the lack of habitat and/or conspecifics attraction cues, either acoustic or chemical. On the other hand polychaetes and opistobranchs showed higher recruitment in control sand habitats. One molluscan species, the pearl oyster, of considerable economic importance in French Polynesia, showed lower growth in the control sand habitat. Differences in recruitment and survival will be discussed as a function of coral cover and habitat degradation, as well as consequences for reef ecosystem conservation and management