Fishy Business: Alleged Fraud over Ocean Acidification Research, Reversal on Coral Extinction

In the news recently have been two revelations about the sometimes controversial world of coral reef research. The first is fraud allegations against research claiming that ocean acidification from global warming impairs the behavior of coral reef fish. The second is an about-face on inflated estimates for the extinction risk of Pacific Ocean coral species due to climate change. 

The alleged fraud involves 22 research papers authored by Philip Munday, a marine ecologist at JCU (James Cook University) in Townsville, Australia and Danielle Dixson, a U.S. biologist who completed her PhD under Munday’s supervision in 2012. The fraud charges were made in August 2020 by three of an international group of mostly biological and environmental scientists, plus the group leader, fish physiologist Timothy Clark of Deakin University in Geelong, Australia. The Clark group says it will publicize the alleged data problems shortly.

The research in question studied the behavior of coral reef fish in slightly acidified seawater, in order to simulate the effect of ocean acidification caused by the absorption of up to 30% of humanity’s CO₂ emissions. The additional CO₂ has so far lowered the average pH – a measure of acidity – of ocean surface water from about 8.2 to 8.1 since industrialization began in the 18th century.

Munday and Dixson claim that the extra CO₂ causes reef fish to be attracted by chemical cues from predators, instead of avoiding them; to become hyperactive and disoriented; and to suffer loss of vision and hearing. But Clark and his fellow scientists, in their own paper published in January 2020, debunk all of these conclusions. Most damningly of all, the researchers find that the reported effects of ocean acidification on the behavior of coral reef fish are not reproducible – the basis for their fraud allegations against the JCU work.

In a published rebuttal, Munday and Dixson say that the Clark group’s replication study differed from the original research “in at least 16 crucial ways” and didn’t acknowledge other papers that support the JCU position.

Nevertheless, while the university has dismissed the allegations after a preliminary investigation, Science magazine points out that a 2016 paper by another former PhD student of Munday’s was subsequently deemed fraudulent and retracted. And Clark and his colleagues say they have evidence of manipulation in publicly available raw data files for two papers published by Munday’s research laboratory, as well as documentation of large and “statistically impossible” effects from CO₂ reported in many of the other 20 allegedly fraudulent papers.

CREDIT: ALEX MUSTARD/MINDEN PICTURES

The about-turn on coral extinction involves another JCU group, the university’s Centre of Excellence for Coral Reef Studies. Four Centre researchers published a paper in March 2021 that completely contradicts previous apocalyptic predictions of the imminent demise of coral reefs, predictions that include an earlier warning by three of the same authors of ongoing coral degradation from global warming.

As an example of past hype, the IUCN (International Union for Conservation of Nature) states on its website that 33% of all reef-building corals are at risk of extinction. The IUCN is highly regarded for its assessments of the world’s biodiversity, including evaluation of the extinction risk of thousands of species. An even more pessimistic environmental organization suggests that more than 90% of the planet’s coral reefs may be extinct by 2050.

The recent JCU paper turns all such alarming prophecies on their head. But the most astounding revelation is perhaps the sheer number of corals estimated to exist on reefs across the Pacific Ocean, from Indonesia to French Polynesia – approximately half a trillion, similar to the number of trees in the Amazon, or birds in the world. To estimate abundances, the JCU scientists used a combination of coral reef habitat maps and counts of coral colonies.

This colossal population is for a mere 300 species, a small fraction of the 2,175 coral species estimated to exist worldwide by the IUCN. And of the 80 species considered by the IUCN to be at an elevated risk of extinction, those in its “critically endangered” and “endangered” categories, 12 species have estimated Pacific populations of over a billion colonies. One of the study’s authors remarks that the eight most common coral species in the region each have a population size larger than the 7.8 billion people on Earth.

The implication of this stunning research is that the global extinction risk of most coral species is lower than previously estimated, even though a local loss can be ecologically devastating to coral reefs in the vicinity. So any future extinctions due to global warming are unlikely to unfold rapidly, if at all.

Next: New Doubts on the Climatic Effects of Ocean Currents, Clouds