Oxygen supersaturation has negligible effects on warming tolerance across diverse aquatic ectotherms.

ABSTRACT: Under the midday sun, when photosynthesizers are producing oxygen, shallow aquatic ecosystems can become supersaturated with oxygen (>100% air saturation) while they simultaneously peak in water temperature. It has been suggested that oxygen supersaturation could protect water-breathing animals from mortality during heatwaves because of the potential role of oxygen in governing thermal tolerance. Here, we conducted a circumglobal assessment of the effects of ecologically relevant oxygen supersaturation (150%, hyperoxia) on warming tolerance (here, measured using critical thermal maximum, CTmax) in 14 aquatic ectotherms from diverse marine and freshwater environments (10 fishes, four decapod crustaceans), in a series of 24 experiments that included 147 CTmax trials and 1,451 animals using t

SUBMITTER: Raby GD 

PROVIDER: S-EPMC12585006 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature