According to a recent paper published in the journal PLOS One, the critically threatened staghorn coral (Acropora cervicornis) has disappeared from 90 percent of its native range in the western Atlantic and Caribbean. In the Florida reef tract, the dominant reef-building coral species has diminished by as much as 98 percent since the 1970s. But there is hope. A new study on Acropora cervicornis and the effects of ocean acidification points out that the feeding of corals may increase their capability to withstand the effects of elevated sea water temperatures and elevated carbon dioxide levels.
Researchers Erica K. Towle and Chris Langdon of the University of Miami Rosenstiel School of Marine and Atmospheric Science and Ian C. Enochs of NOAA’s Atlantic Oceanographic and Meteorological Laboratories in Miami conducted studies on eight genetically diverse colonies of staghorn corals and subjected them to differing levels of sea water temperature increases and carbon dioxide levels. They also fed one group of the study subjects a diet of dried zooplankton two times a week for eight weeks.
Towle, Langdon and Enochs determined that those corals that were fed twice weekly grew normally even though the water temperatures (30°C) and carbon dioxide levels (800 ppm) were higher. The corals were able to increase their feeding rate and stored energy reserves when exposed to these conditions. The unfed coral did not grow as robustly as those that were fed.
“For many years we have known some types of symbiotic algae can convey climate change resilience to corals,” said co-author Chris Langdon, UM Rosenstiel School professor and chair of marine biology and ecology. “This study shows that behavioral and possibly physiological differences in the animal, which is half of the coral-algal symbiosis, can also convey resilience and not just to climate change but also to ocean acidification.”
The full study, Threatened Caribbean Coral Is Able to Mitigate the Adverse Effects of Ocean Acidification on Calcification by Increasing Feeding Rate can be read on the PLOS One Journal website.