Predicting the sensitivity of marine populations to rising temperatures

Oceans are warming at rates faster than marine species have experienced over the previous 400,000 years. Our quantitative review across a wide range of marine taxa revealed that increases in temperature that occur above mean annual temperature (MAT) generally lower population survival and reproduction. Furthermore, these effects are likely to be increasingly detrimental, particularly for survival, as the magnitude of warming increases. Although we found evidence for considerable variation within and between populations in response to increasing temperatures, whether this existing variation will allow for evolutionary rescue is uncertain. Importantly, a simple metric (ie MAT) facilitates evaluation of the effects of increasing temperatures on the survivorship and reproduction of most populations, even those for which limited data on thermal sensitivity are available. This approach improves our understanding of population-level responses to climate change, which is critical for adaptation planning that aims to sustain and restore vulnerable populations.