The partial pressure of CO₂ in the oceans has increased rapidly over the past century, driving ocean acidification and raising concern for the stability of marine ecosystems^1,2,3. Coral reef fishes are predicted to be especially susceptible to end-of-century ocean acidification on the basis of several high-profile papers^4,5 that have reported profound behavioural and sensory impairments—for example, complete attraction to the chemical cues of predators under conditions of ocean acidification. Here, we comprehensively and transparently show that—in contrast to previous studies—end-of-century ocean acidification levels have negligible effects on important behaviours of coral reef fishes, such as the avoidance of chemical cues from predators, fish activity levels and behavioural lateralization (left–right turning preference). Using data simulations, we additionally show that the large effect sizes and small within-group variances that have been reported in several previous studies are highly improbable. Together, our findings indicate that the reported effects of ocean acidification on the behaviour of coral reef fishes are not reproducible, suggesting that behavioural perturbations will not be a major consequence for coral reef fishes in high CO₂ oceans.

在过去的一个世纪里，海洋中 CO ₂的分压迅速增加，推动了海洋酸化并引发了对海洋生态系统稳定性的关注^1,2,3。^{根据几篇备受瞩目的论文4,5}，珊瑚礁鱼类预计特别容易受到世纪末海洋酸化的影响已经报告了严重的行为和感觉障碍——例如，在海洋酸化条件下完全吸引捕食者的化学线索。在这里，我们全面而透明地表明，与以前的研究相比，世纪末的海洋酸化水平对珊瑚礁鱼类的重要行为的影响可以忽略不计，例如避免来自捕食者的化学线索、鱼类活动水平和行为偏侧化（左右转向偏好）。使用数据模拟，我们还表明，在之前的几项研究中报告的大效应量和小的组内方差是极不可能的。总之，我们的研究结果表明，海洋酸化对珊瑚礁鱼类行为的影响是不可重现的，₂大洋。