A thorny issue for coral

The increasing acidification of our oceans may lead to an increase in the growth of juvenile crown-of-thorns starfish (Acanthaster planci), according to researchers from Southern Cross University in Australia. The starfish, which feed on pink 'coralline' algae, were found to grow quicker in the higher-carbon dioxide (CO2) oceans that are predicted to occur before the end of the century. This species is already destroying coral reefs, and as the oceans become more acidic by absorbing increasing concentrations of atmospheric CO2, the algal blooms, which the starfish feed on, are less able to defend themselves as the hard calcium carbonate in its tissue is inhibited by the higher acidity, becoming more edible and nutritious for baby starfish.