High CO2 and marine animal behaviour: Potential mechanisms and ecological consequences

► Pollution is known to change the behaviour of marine animals. ► We review evidence that elevated CO2 to alters marine animal behaviour. ► Potential mechanisms include reduced metabolic scope, info-disruption and avoidance behaviour. ► Altered behaviour in crustaceans and fishes is due to info-disruption, potentially as a result of impaired cognitive systems. ► Changes across a range of behavioural contexts might have knock-on ecological impacts.