Arguably climate change is one of the biggest challenges faced by many organisms. One of the more significant of these is the decreasing pH level of the ocean, a consequence of the increasing amount of atmospheric CO₂ being absorbed. With the current open ocean pH level of 8.15 projected to fall to just over 7.6 in 2100, the impacts could be devastating for marine species reliant upon olfaction to survive. Here, we show that Carcinus maenas (shore crab) can detect and respond to the presence of odour cues from predatory species with no significant change between both current and projected pH conditions. In contrast, C. maenas ability to detect and respond to prey cues is altered in the projected climate change conditions, with a delayed response being observed at pH 7.6. A difference can be seen between males and females, with males detecting prey cues faster than females in reduced pH, suggesting the potential for males to be better acclimated to future climate change conditions. The change in ocean chemistry is postulated to have a fundamental impact on chemical communication systems in aquatic species. Here, we show such negative impacts of altered pH on feeding responses in Carcinus maenas, a typically robust keystone intertidal species and confirm that not all behaviours are affected equally with potentially significant implications for such functional traits and species interactions.

可以说，气候变化是许多生物面临的最大挑战之一。其中一个更重要的是海洋的 pH 值降低，这是大气 CO ₂吸收量增加的结果。由于目前公海 8.15 的 pH 值水平预计将在 2100 年降至略高于 7.6，对于依赖嗅觉生存的海洋物种来说，这些影响可能是毁灭性的。在这里，我们展示了Carcinus maenas（岸蟹）可以检测和响应来自掠食性物种的气味线索的存在，而当前和预计的 pH 条件之间没有显着变化。相比之下，C. maenas在预测的气候变化条件下，检测和响应猎物线索的能力会发生变化，在 pH 7.6 时观察到延迟响应。雄性和雌性之间存在差异，在 pH 值降低的情况下，雄性比雌性更快地检测到猎物线索，这表明雄性有可能更好地适应未来的气候变化条件。据推测，海洋化学的变化会对水生物种的化学通讯系统产生根本性的影响。在这里，我们展示了改变 pH 值对Carcinus maenas摄食反应的负面影响，这是一种典型的强大的潮间带关键物种，并确认并非所有行为都受到同等影响，对此类功能性状和物种相互作用具有潜在的重大影响。