Research Example #5

In “The 27-year decline of coral cover on the Great Barrier Reef and its causes,” De’ath and the other researchers studied for more than two decades what is making the coral reefs at the Great Barrier Reef die quicker and quicker. This article is great source for my research project because it lists many drivers that affect coral reef mortality, and the few that are only affecting the Great Barrier Reef, especially the southern side. The drivers that these researchers believe are affecting reefs worldwide are the rising seawater temperature, pollution, ocean acidification, overfishing, destructive fishing, tourism, development along the coast, predation and storms (De’ath et al, 2012). After measuring the mean coral coverage in three areas of the Great Barrier Reef for 27 years, the researchers decided cyclones, the increase in the invasive species Crown-of-Thorns Starfish, and coral bleaching which is influenced by the rising temperature of seawater. These drivers affected the rate of regrowth of the coral. Since the temperature has risen in the water and out, tropical cyclones are more frequent and more tense, which physically damages the coral. That means the coral has less time to regrow if there are more storms. Crown-of-Thorn Starfish eat coral, and the more there are of these starfish, the more coral is being eaten. The rising water temperature cause coral to bleach because the hotter temperatures kill off the algae that gives nutrients to coral. Without the algae, the coral stops growing and reproducing. If the coral is bleached for a short period, it will be able to revive itself. Unfortunately, the bleaching periods have become longer and the coral is not able to recover from it. These three drivers affect the coral in the Great Barrier Reef, and other combinations of drivers affect other reefs. It was interesting to learn that the declining rate of coral growth was more deadly than bleaching on its own, or storms.

De’ath, G., Fabricius, K. E., Sweatman, H., and Puotinen, M. (2012). The 27 year decline of cora; cover on the Great Barrier Reef and its causes, PNAS 109(44): 17995-17999