New images of the Great Barrier Reef show that rising water temperatures have severely damaged the world’s largest reef system, which stretches for over 1,400 miles off the coast of Australia. [1]
How bad is it? Hmm. It depends on who you ask.
One scientist who visited the reef said that “if it was a person, it would be on life support.”
Last week, Outside Magazine reported that the Great Barrier Reef had “passed away in 2016 after a long illness.” Well, it’s not dead, but some researchers say it’s just barely hanging on. [2]
In May, researchers found that more than 1/3 of the coral in northern and central parts of the reefs was dead, and 93% of individual reefs had been affected by coral bleaching. [1]
When the water gets too warm, corals expel zooxanthellae algae living in their tissues, causing the coral to turn completely white. Corals can survive bleaching, but it puts them under great stress and makes them more likely to die. [3]
The algae provide about 90% of the coral’s energy. Without it, the coral eventually starves to death. [2]
Scientists say the problem is getting worse.
Amanda McKenzie, CEO of the Australian Climate Council, said:
“After the bleaching event in May, 60 per cent of what we saw was bleached very white. Another 19-20 per cent was covered in sludgy brown algae. Even of what remained healthy, some looked a bit on edge.
When we went back a few weeks ago to see if they had recovered or died, quite a large proportion had died.” [1]
McKenzie estimated that approximately half of the bleached corals they visited had died, and that the bleaching had mostly affected delicate corals rather than the stronger “brain corals.”
McKenzie and her colleagues also found fewer species of fish around the reef.
Professor Tim Flannery said that coral he visited in September was “bleached and in danger a few months back has now mostly died.”
Click for larger version.
He added:
“On top of that we’ve seen a whole lot of new damage, a whole lot of white coral out there that’s been killed by Crown of Thorns starfish because it was too weak to defend itself. If it [the reef] were a person, it would be on life support.”
Russell Brainard, chief of the Coral Reef Ecosystem Program at NOAA’s Pacific Islands Fisheries Science Center, said it’s unfortunate that Outside Magazine posted a premature obituary for the reef, because it can make people who don’t know any better lose hope and think that nothing else can be done. [2]
Terry Hughes, director of the ARC Centre of Excellence for Coral Reef Studies, agreed. He said:
“The message should be that it isn’t too late for Australia to lift its game and better protect the Great Barrier Reef, not we should all give up because the Great Barrier Reef is supposedly dead.”
More than Half is Still Living
But despite all the dire warnings and concerning discoveries by researchers who have visited the Great Barrier Reef, the truth is that more than half of it is still alive. Brainard said that “These natural systems do have some ability to be resilient and bounce back.”
Source: National Geographic – A healthy section of the Great Barrier Reef
In March 2015, the Australian government unveiled its Reef 2050 Plan to help save the Great Barrier Reef. The plan includes improving water quality to help corals recover from bleaching. Rerouting boats around the reef, limiting fertilizer and sewage runoff that damages coral, and avoiding overfishing key animals that eat excessive algae can also save the Great Barrier Reef.
The only drawback of the plan is that improving water quality will cost $8.2 billion in the next decade, 10 times what the local and federal governments currently spend.
Sources:
[1] The Telegraph
[2] The Verge
[3] National Ocean Service
National Geographic