Concurrent thermal stress and flood-plume disturbance drive rapid coral community change on an inshore intertidal reef on the Great Barrier Reef

and mean genus richness from 16.58 to 5.17 between 2024 and 2025. Reef sites beyond the gradient declined similarly but retained comparatively higher live hard coral cover than gradient sites, indicating that mangrove proximity did not buffer coral declines. Benthic composition shifted from coral-dominated to turf-algae-dominated substrate across all sites. Colony density declined most strongly in sensitive genera (Acropora, Pocillopora, Montipora) but also in normally more stress resistant taxa (Favites, Lobophyllia, Galaxea). Porites remained the most abundant genus in 2025, though its colony density declined by ∼25% from the previous year. These results indicate that concurrent thermal and flood-plume disturbance can rapidly restructure inshore coral communities, even among normally stress-tolerant taxa.