Safety in Numbers? Abundance May Not Safeguard Corals from Increasing Carbon Dioxide

Marine conservation efforts are often focused on increasing stocks of species with low population abundances by reducing mortality or enhancing recruitment. However, global changes in climate and ocean chemistry are density-independent factors that can strongly affect corals whether they are scarce or abundant-sometimes, the abundant corals are most affected. Because reproductive corals are sessile, density-independent effects of global changes such as physiological stress and resultant mortality can decouple stock abundance from recruitment and may accelerate the downward spiral of their reproductive rates.