Scientists may have gotten a preview of the future state of coral reef ecosystems – and the view beneath the surface wasn’t a pretty one. This environmental fast forward didn’t involve time travel or lab experiments, as scientists were able to look at existing habitats off the Yucatan Peninsula, whose conditions resemble those estimated for our coastal waters at the end of this century.
While oceans continue to acidify as surface waters absorb increasing amounts of carbon dioxide, there are dangerous consequences for marine life. The lowering of pH, known as ocean acidification, makes it difficult for organisms to build structures out of calcium carbonate. This reduction in carbonate ions could spell disaster for a variety of animals, in particular most coral species.
Researchers from UC Santa Cruz conducted a series of underwater surveys in submarine springs off eastern Mexico. The springs, also known as ojos, naturally have more acidic conditions. The pH of the ojos is similar to predictions for our oceans in 2100. Dives beneath the surface revealed patchy colonies with lower coral diversity. Complex reefs with a variety of coral species were absent.
While it is promising that some coral species will be able to tolerate a more acidic oceans, it seems the complexity and diversity that makes them so dynamic may live on only in pictures.