Patterns of Coral Recruitment and Post-settlement Mortality on Bermuda's Reefs: Comparisons to Caribbean and Pacific Reefs

The recruitment of juvenile corals and post-settlement mortalityare important processes for coral population dynamics and reefcommunity ecology. I monitored juvenile coral recruitment andsurvival on a severely disturbed reef in Bermuda from 1981 to1989 and on adjacent healthy reefs from 1986 to 1990. Poritesastreoides was the dominant recruiting species at all sites,due to the release of brooded planulae that may settle rapidly.The dominant corals on Bermuda's reef, Diploria spp., were poorrecruiters, perhaps due to the broadcast mode of reproductionof these species. However, Diploria spp. have lower juvenilemortality rates compared to P. astreoides, which may explaintheir abundance on Bermuda's reefs. Brooding corals, primarily agariciids, were the dominant recruitson Atlantic reefs compared to high recruitment rates by spawningacroporids in the Pacific, which may be the result of differentenvironmental conditions and/or evolutionary trends in the twooceans. The latter group also suffered high post-settlementmortality compared to brooding coralsin both the Atlantic andthe Pacific. Massive corals in both oceans had generally lowrecruitment rates, related to their spawning mode of reproduction,and low rates of post-settlement mortality. The dominant roleof long-lived massive corals on the Atlantic and Pacific reefscan be understood in terms of their life-history strategy incomparison to the relatively short-lived Pacific acroporidsand Atlantic agariciids that rely on different strategies tomaintain their populations.