The size-structure of corals with contrasting life-histories: A multi-scale analysis across environmental conditions

• Size-structure of 3 coral taxa was measured at multiple scales in the Society Islands.
• A strong heterogeneity in the size-structure was found for all taxa at all scales.
• We demonstrated the importance of life-history traits and environmental factors.
• These results may serve as baseline data for future surveys and monitoring programmes.

We report variation in the size-structure of three coral taxa in the Society Islands (French Polynesia) using a hierarchical sampling design that integrates the regional (among three islands: Moorea, Raiatea, Tahiti), island (among three locations around each island), and local levels (among three depths: 6, 12, 18 m, at each location). All coral taxa exhibited strong heterogeneity in their size-structure, with marked variation among depths, locations, and islands. Porites spp. and Acropora globiceps populations at 6 m depth were dominated by smaller size classes compared to other depths. Regional-scale variation was particularly evident for Pocillopora meandrina and A. globiceps, with a higher proportion of smaller colonies found at Raiatea, probably as a result of recent cyclones followed by higher recruitment rates. Porites spp. populations were characterized by a preponderance of larger colonies, and greater size ranges compared to the other two taxa.