Past research on coral growth and mortality in the first year of life has been limited to species which brood their larvae. The larvae of three broadcast-spawning scleractinians, (Goniastrea aspers, Platygyra sinensis, Acropora millepora) were raised in sufficient numbers to obtain data on post-settlement growth and mortality. These are the first data on the growth of post-settlement stages < 1 year) for non-planulating species.\ud
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Larvae were capable of settlement 3 to 4 days after spawning, at which time they were transferred to aquaria supplied with cut plates of coral. After settlement, these plates were deployed on reefs at Magnetic Island and at Orpheus Island. Zooxanthelae were not present in G. aspera or P. sinensis larvae, or in spat 5 days after settlement on the reef. After 10 days, juveniles of all three species contained zooxanthellae.\ud
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The growth rates of juvenile G. aspera, P. sinensis and A. millepora (1.5-6.8 mm mean diameter in the first year) are considerably slower than those of juveniles from planulating species (greater than 10 mm diameter).\ud
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The growth rates of G. aspera and P. sinensis were very similar, (1.6 and 1.4 mm diameter) while A. millepora (6.8 mm diameter) grew much more rapidly than either of the massive species. These growth rates are less than half those reported for the spat of planulating species of scleractinia.\ud
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Rates of mortality during the first year of life for scleractinian corals in situ are reported for the first time. Mortality of juveniles was calculated between the time of their first measurement (1-2 months old) and their most recent measurement (8-9 months old). The rate of mortality was similar for all three species, however the overall mortality of A. millepora (86%) was slightly higher than that of either of the two massive species, G. aspera (67%) and P. sinensis (73%) over the first 8 months of life
