Rock and roll: experiments on substrate movement and coral settlement

• DOI: 10.1007/s00338-024-02547-z
• Publication Date: 2024-08-29T12:02:09Z
• Authors: Andrew Heyward; Christine Giuliano; Cathie A. Page; Carly J. Randall
• Keywords: Settlement (finance)

Rubble is ubiquitous on coral reefs and can aggregate into fields, forming a significant component of the reef substrate. fields often remain unconsolidated, with rubble pieces subject to movement that dependent hydrodynamic forcing, size, shape, other factors. Settlement corals has long been assumed, but dynamic presumed deter settlement thought contribute high post-settlement mortality. forms following severe disturbances, predicted increase under climate change, potential impact recruitment-dependent recovery processes. Through series laboratory field experiments, we demonstrate from broadcast spawning species Great Barrier Reef will settle unstable substrates, even those in constant motion. We also observed more spat tiles suspended water column than fixed using common approach censusing settlement. Sampling natural 50 days after mass-spawning event confirmed presence similar numbers settlers reef. These results suggest are places for corals. Suspended were surprisingly effective collecting settlers, demonstrating change sampling protocol produce variation data strengthening argument standardisation settlement-monitoring protocols, particularly at time growing need reliable metrics. not precluding outright, rather processes (i.e. competition, predation, shading or burial by shifting rubble) limiting recruitment patches. Consequently, stabilisation may survival have settled these environments.