New research delivers hope for reef fish living in a high CO2 world—31 August 2017 

Research by ARC Centre of Excellence for Coral Reef Studies (CoralCoE) at James Cook University is helping understand the implications of ocean acidification on reef fish behaviour. Chemical changes in the ocean are leading to a more acidic environment, referred to as ‘ocean acidification’ (OA). In a laboratory setting, these changes have been shown to lead to a range of risky behaviours in the affected fish, with some fish unable to flee from their finned foes effectively. But, when researchers recalibrated experiments to adjust for natural daily changes in concentrations of dissolved carbon dioxide (CO2), the primary chemical driver of OA, they found that the fish were less affected than previously thought.

Professor Philip Munday from CoralCoE said that shallow water habitats where reef fish live can experience substantial natural fluctuations in water chemistry throughout the day. For example, carbon dioxide levels on coral reefs are often much lower during the day than they are at night.

“Our data suggests that these natural daily changes in water chemistry are enough to provide fish with a recovery period, reducing their sensitivity to higher carbon dioxide levels,” said Michael Jarrold, lead researcher and PhD student.

The study utilised state-of-the-art facilities at James Cook University and at the Australian Institute of Marine Science’s National Sea Simulator (SeaSim) to mimic the natural conditions of a coral reef environment. “It’s the first time these dynamic natural conditions have been reproduced in a laboratory setting to test their potential influence on the behaviour of coral reef fish,” explained Mr Jarrold.


Media issued by the ARC Centre of Excellence for Coral Reef Studies.

Image: Orange clownfish, Amphiprion percula, living in symbiosis with a host anemone.
Image credit: Alejandro Usobiaga.

Original Published Date: 
Thursday, August 31, 2017