A framework for understanding climate change impacts through non-compensatory intra- and interspecific climate change responses

Understanding and predicting population responses to climate change is a crucial challenge. A key component of population responses to climate change are cases in which focal biological rates (e.g., population growth rates) change in response to climate change due to non-compensatory effects of changes in the underlying components (e.g., birth and death rates) determining the focal rates. We refer to these responses as non-compensatory climate change effects. As differential responses of biological rates to climate change have been documented in a variety of systems and arise at multiple levels of organization within and across species, non-compensatory effects may be nearly ubiquitous. Yet, how non-compensatory climate change responses combine and scale to influence the demographics of populations is often unclear and requires mapping them to the birth and death rates underlying population change. We provide a flexible framework for incorporating non-compensatory changes in upstream rates within and among species and mapping their consequences for additional downstream rates across scales to their eventual effects on population growth rates. Throughout, we provide specific examples and potential applications of the framework. We hope this framework helps to enhance our understanding of and unify research on population responses to climate change. Understanding and predicting how populations are responding to climate change is a major challenge. Here Coblentz et al. develop a hierarchical framework to examine how non-compensatory changes in rates can ultimately lead to population growth or decline with climate change. Applying this framework will help researchers to understand why particular populations may be declining or increasing with climate change and to predict how different aspects of climate change might affect focal populations.image