Predator-Prey Dynamics Under Ocean Acidification

Ocean acidification, driven by rising atmospheric carbon dioxide, alters the chemical composition of seawater and has profound consequences for predator and prey interactions in marine ecosystems. Changes in pH and carbonate chemistry can impair sensory systems that predators and prey use to detect one another, disrupt escape and attack behaviours, and shift the balance between consumptive and non-consumptive effects. Prey species may exhibit altered locomotion, reduced refuge seeking and modified shell or skeletal strength, while predators can suffer from slower foraging rates, impaired prey detection and increased handling times. The net outcome is a re-organisation of trophic interactions that may cascade through food webs, altering community structure, nutrient cycling and ecosystem resilience. Recent work highlights both negative and occasionally compensatory responses, with some taxa showing phenotypic plasticity that mitigates stress impacts, whereas others experience heightened predation risk or diminished predatory efficiency. Understanding these dynamics is essential for predicting the future of fisheries, reef stability and the functioning of coastal habitats under ongoing environmental change.

Research from Nature Portfolio

Studies on a keystone marine mollusc have demonstrated that exposure to near-future levels of ocean warming and acidification in isolation reduces locomotor performance and foraging success by up to two-fold, but when combined can impair movement and decision-making by as much as three-fold. Metabolic demands are elevated under joint stressors, although individuals that develop under these conditions exhibit partial acclimation through phenotypic plasticity. These findings reveal that early life-history exposure may buffer some impacts, yet increased energetic costs and slower prey capture rates are likely to diminish predator fitness and alter prey population dynamics in reef and seagrass communities.

Predator-Prey Dynamics Under Ocean Acidification publication trend

The graph below shows the total number of articles in predator-prey dynamics under ocean acidification across all publications each year (not limited to Nature Index journals).

Technical terms

Ocean acidification: The decrease in seawater pH and carbonate ion concentration resulting from uptake of atmospheric CO₂.

pCO₂: Partial pressure of carbon dioxide, a measure of CO₂ concentration in seawater influencing acid–base balance.

Non-consumptive effects: Predator-induced changes in prey behaviour or physiology that occur without direct consumption.

Phenotypic plasticity: The ability of an organism to alter its morphology, physiology or behaviour in response to environmental stress.

Chemosensory cues: Chemical signals in water used by predators and prey to detect each other and assess risk.

References

1. Ocean Acidification Disrupts Prey Responses to Predator Cues but Not Net Prey Shell Growth in Concholepas concholepas (loco). PLOS ONE (2013).
2. Ocean Acidification and Increased Temperature Have Both Positive and Negative Effects on Early Ontogenetic Traits of a Rocky Shore Keystone Predator Species. PLOS ONE (2016).
3. Near-future ocean warming and acidification alter foraging behaviour, locomotion, and metabolic rate in a keystone marine mollusc. Scientific Reports (2020).