The increasing amount of carbon dioxide dissolved in oceans is literally driving fish crazy, according to an Australian researcher.

Professor Phillip Munday of the ARC Centre of Excellence for Coral Reef Studies and James Cook University explains that the CO2 interferes with their ability to hear, smell, and swim – the most important things for a fish.

“For several years our team have been testing the performance of baby coral fishes in sea water containing higher levels of dissolved CO2 – and it is now pretty clear that they sustain significant disruption to their central nervous system, which is likely to impair their chances of survival,” he says.

Munday and his team showed that the dioxide alters a key brain receptor in fish, causing significant changes in their sensory and motor abilities.

“We’ve found that elevated CO2 in the oceans can directly interfere with fish neurotransmitter functions, which poses a direct and previously unknown threat to sea life,” he says.

Of course, the 2.3 billion tonnes of human CO2 emissions dissolved into the world’s oceans every year have a lot to do with this problem, causing chemical changes in the environment where the animals live.

“We’ve now established it isn’t simply the acidification of the oceans that is causing disruption – as is the case with shellfish and plankton with chalky skeletons – but the actual dissolved CO2 itself is damaging the fishes’ nervous systems.”

Via TG Daily