Author: Dr Peter Ridd


Published: May 11, 2022


Originally Appeared In: Dr Peter Ridd's Facebook Page

GBRMPA released its report of aerial surveys of coral bleaching this year. It again looks like Doom, but these aerial surveys are totally useless at predicting coral death and GBRMPA should have waited until some of the surveys from divers were completed. This looks like rampant opportunism almost deliberately designed to give the wrong impression - not carefully considered reporting.

Because there has been so much misinformation about bleaching, most people think the red patches of bleaching on these maps represent coral death – massive coral death. GBRMPA has pointed out that this is not the case in the text of their report, an improvement over previous years. However, they should have waited until they could give figures on mortality.

Most bleached coral fully recovers.

They should also have pointed out that aerial surveys can only see coral in shallow water and that corals in deep water are usually much less affected.

Why did they not mention that the reef presently has record high, or near record high, coral cover in 2020/21 (see my previous posts) which proves that the last bleaching events could not have been serious or long lasting. That statistic is too embarrassing so they don’t mention it.

2016 was the only year when there was significant mortality – about 8% over the entire reef (see my book “Reef Heresy” for details). But the reef totally recovered within 5 years, and considering the southern third of the reef had a 250% increase in coral cover between 2011 and 2016, an 8% decrease is not a big deal. For 2020, which looked almost as bad as 2016, GBRMPA admit that there was very little mortality.

What we are seeing as the years of surveys accumulate is that bleaching is a common, but not very damaging, phenomenon.

So these aerial surveys, whilst interesting and doubtless well executed, because this year it was done by AIMS rather than JCU coral reef centre, it will inevitably give the wrong impression to the public if they are not accompanied by useful information on mortality. This year’s data looks much like previous years so we can expect very little mortality. For these aerial surveys to be useful they need to be calibrated against data collected by divers. Again, poor quality science reporting by GBRMPA.

John Brewer Reef is marked as having 61-90% bleaching. Jennifer Marohasy and I, as part of the Reef Rebels program, checked out this reef – by diving – and we found spectacular coral (see previous posts). Certainly, there was some bleaching but almost no mortality. Only by diving can the true significance of these events be gauged. The AIMS long term monitoring program results will give us an idea of what actually happened.

This news will again ripple around the world and damage even further the reputation of what is one of the most pristine and well protected ecosystems on earth. It is staggering that most people around the world think our beautiful Great Barrier Reef is almost dead.

Heaven help our reef tourist industry. How much longer can it survive this onslaught against its reputation. Will they finally stand up and tell us what they see every day on the reef?

In particular, it is a crime that young people have been deceived that the reef is finished. Apparently a large fraction of them are in depression about its future, or lack thereof.

The timing of this result will be significant in terms of the election. It will be used as “proof” that the world is ending and Australia must go to Net-Zero. It will be yet another example of how misleading “science” will have an impact on public policy and possibly even who forms government. One can only hope that at least one of the major political parties will finally realise that they will be at the mercy of these unreliable science organisations until they tackle the root cause if the problem.

And the problem is not the Reef – it is fine.

The problem is that we have a major quality assurance problem with environmental science institutions.

https://www.youtube.com/watch?v=Foa0fn2iTIQ
https://www.gbrmpa.gov.au/the-reef/reef-health

- Dr Peter Ridd