Benthic communities were assessed and 22 environmental variables were monitored at seven leeward localities (L1ŒL7) in the Whitsunday Islands, Queensland, Australia. L1 was near the Proserpine and O’Connell river mouths and L7 ~80 km north of the river mouths. Distinct physico Œchemical and biological gradients were evident. Sparse scleractinian coral communities, dominated by faviids, Montipora spp. and encrusting Porites colonies, were present at L1, L2 and L3, whereas diverse reef-building communities, dominated by Acropora spp., were more common at and beyond L4. The number of coral recruits (age <6 months) did not differ significantly among localities, suggesting that coral recruitment was near random and that the environment shapes the adult community from those recruits. The study demonstrates strong negative relationships between chlorophyll a and the following: percentage coral cover, coral species richness and coral abundance. The reef-building capacities of the coral communities and the extent of Holocene reef development were inconsistent at L2 and L3, which is interpreted as a sign of anthropogenic effects.

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Artificial substrate settlement plates (terracotta tiles) were set out on 3 fringing reefs for a period of 12 mo to study settlement patterns of juvenile scleractinian corals along a eutrophication gradient on the west coast of Barbados, W.I. A total of 716 coral planulae settled on 120 experimental plates after 12 mo of exposure. Statistically higher ( p 0.05) average number of juvenile corals per plate (R= 9.2 f 3.3; N = 40) was recorded on a less eutrophic reef compared to 2 more eutrophic reefs (X = 6.9 f 3.1; N = 40 and X = 1 9 i 1.3; N = 40) Differences in juvenile coral settlement between reef zones, within each reef, were dependent on the reef's position along the eutrophication gradient. Statistically higher number of coral planulae (;if = 7.2 + 4.5; N = 60) successfully settled on vertical plates compared to horizontal plates (X = 4.8 + 3.3; N = 60). Coral planulae did not settle on upper surfaces of horizontal plates. In terms of relative abundance, the most common coral species in the juvenile population on the experimental plates were Porites astreoides Lamarck which accounted for 42% of the settled planulae, followed by Agaricia spp. (23%); and F! porites (Pallas) (19%). Juveniles of Montastrea annularis (Ellis & Solander), Siderastrea spp, and Diplona spp , while present at 2 northern reefs, were absent from the most eutrophic reef.

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