How many settlers per substrate are estimated to yield one surviving coral?

The estimate that 10-50 settlers per substrate are needed to yield one surviving coral is based on ecological principles of recruitment and survivorship in coral reef environments. Coral larvae that settle on substrates often face a variety of challenges, including predation, competition for space, and environmental stressors.

Research has shown that not all coral settlers will survive to adulthood due to these pressures. The wider range of 10-50 settlers accounts for variations in species, environmental conditions, and the health of the surrounding ecosystem. This estimate reflects the understanding that while a certain number of settlers can attach to a substrate, the actual survival rate is influenced by multiple factors, thus necessitating a higher number of initial settlers to ensure the establishment of at least one coral in the long-term.

In comparison, numbers outside of this range, such as the higher options, would suggest an excessively high number of necessary settlers that may not correspond with ecological observations and studies conducted on coral recruitment dynamics. On the lower side, fewer than 10 settlers would likely be too low to ensure even one coral might survive, clarifying why the chosen range is considered the most accurate for restoration efforts.