Ocean acidification caused by rising CO2 is disrupting marine animal behavior and physiology in ways that constitute a growing welfare crisis.
Ocean acidification represents a welfare harm operating at a scale that dwarfs all anthropogenic animal welfare interventions combined. The disruption of fish neurotransmitter systems by elevated CO2 impairs their ability to avoid predators, find food, and navigate, affecting both individual welfare and survival. The destruction of coral reef ecosystems removes food, shelter, and reproductive habitat for an estimated 25% of all marine species. Addressing ocean acidification requires climate action at a scale that makes all other welfare interventions pale in comparison.