The harmful effects of carbon dioxide are well known by all, but are they restricted to just human beings? Answering this question, scientists from the University of Oslo have revealed that carbon dioxide emissions are apparently harming the central nervous system of fishes in seawater and this is threatening their survival.
The scientists found that higher levels of carbon dioxide in the water appeared to interfere with the GABA-A receptor, which is a principal molecule in the brain. This receptor is supposedly responsible for the sensory and behavioral capabilities of fishes.
“CO2 concentrations predicted to occur in the ocean by the end of this century will interfere with fishes’ ability to hear, smell, orient and evade predators,” cited Professor Goran Nilsson from the Department of Molecular Biosciences.
Previous studies have shown that higher proportions of carbon dioxide in the sea may expose fishes to predators, as they are not able to locate a reef and smell the peril awaiting them properly. Considering that the aforesaid receptor is universally present, the findings should be a cause for concern.
The involved team is of the opinion that fishes which breathe more of oxygen in the water are at greater risk, as a larger portion of their gills are exposed to the sea. Fishes like tuna and mackerel fall under this category. Also, fishes with dysfunctional GABA-A receptors appeared to lose their innate intuition to keep to the left or right, which could easily bring them to the notice of predators.
By far, the assumption that acidification alone leads to destruction of marine wealth may not be true. This study suggests that the mere presence of carbon dioxide could harm the nervous systems of fishes. The article titled, ‘Near-future CO2 levels alter fish behavior by interfering with neurotransmitter function’ is published in the journal, Nature Climate.