Severe tissue damage in Atlantic cod larvae under increasing ocean acidification

Abstract

Ocean acidification—resulting from anthropogenic carbon dioxide emissions to the atmosphere—has been shown to affect fish growth rates and reproduction. Now research shows detrimental effects of ocean acidification on the development of Atlantic cod larvae—a mass-spawning fish species of high commercial importance—suggesting that ocean acidification could cause additional larval mortality, affecting populations of already exploited cod stocks. Ocean acidification, caused by increasing atmospheric concentrations of CO2 (refs 1, 2, 3), is one of the most critical anthropogenicthreats to marine life. Changes in seawater carbonate chemistry have the potential to disturb calcification, acid–base regulation, blood circulation and respiration, as well as the nervous system of marine organisms, leading to long-term effects such as reduced growth rates and reproduction4,5. In teleost fishes, early life-history stages are particularly vulnerable as they lack specialized internal pH regulatory mechanisms6,7. So far, impacts of relevant CO2 concentrations on larval fish have been found in behaviour8,9 and otolith size10,11, mainly in tropical, non-commercial species. Here we show detrimental effects of ocean acidification on the development of a mass-spawning fish species of high commercial importance. We reared Atlantic cod larvae at three levels of CO2, (1) present day, (2) end of next century and (3) an extreme, coastal upwelling scenario, in a long-term ( months) mesocosm experiment. Exposure to CO2 resulted in severe to lethal tissue damage in many internal organs, with the degree of damage increasing with CO2 concentration. As larval survival is the bottleneck to recruitment, ocean acidification has the potential to act as an additional source of natural mortality, affecting populations of already exploited fish stocks.

Cite this article

Frommel, A., Maneja, R., Lowe, D. et al. Severe tissue damage in Atlantic cod larvae under increasing ocean acidification. Nature Clim Change 2, 42–46 (2012). https://doi.org/10.1038/nclimate1324

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