The Great Barrier Reef has long been the world’s largest coral reef system, but a new study shows that half of the reef has disappeared in the last 27 years.
Katharina Fabricius, who is a coral reef ecologist at the Australian Institute of Marine Science and co-author of the latest study, states that she has been diving and working on the Great Barrier Reef since 1988, reports CBS News.
Because of this Fabricius has seen firsthand the decline of the reef. The ecologist stated:
“I hear of the changes anecdotally, but this is the first long-term look at the overall status of the reef. There are still a lot of fish, and you can see giant clams, but not the same color and diversity as in the past.”
Fabricius and her colleagues surveyed 214 different reefs that surround the Great Barrier Reef and also compiled information from 2,258 different surveys to find the reef’s rate of decline between 1985 and 2012. They also estimated the amount of the seafloor that is covered with living coral.
They discovered that the reef has declined by 50 percent in less than 30 years, making it a yearly loss of about 3.4 percent of the reef. There were some local differences in the study, which showed that the relatively pristine northern region of the world’s largest coral reef showing no declined in the past 20 years.
The Los Angeles Times notes that the Great Barrier Reef’s decline is attributed to three things: tropical cyclones, attacks from the crown-of-thorns starfish (a coral predator), and rising water temperatures. Because of this coral cover in the area off Australia’s eastern coast has dropped from 28 percent to 13 percent in 27 years.
The study is just one of many that shows the human impact on the natural environment around us, despite the fact that significant efforts are being made to protect the region. Scientists believe that the increase of cyclones and rising water temperatures are related to global warming.
Given that more intensive farming efforts and runoff can increase the nutrient content in the water and help rising populations of predatory fish, the scientists believe that all three reasons that the Great Barrier Reef is disappearing are preventable problems.
While the best option for saving the Great Barrier Reef is almost impossible (an international global warming treaty), researchers believe they can do something about the starfish. If they can stop the starfish from destroying the reef, then they can decrease the destruction by 42 percent.