Assessing the Relative Importance of Factors at Multiple Spatial Scales Affecting Terrestrial and Aquatic Wildlife

Abstract

We reviewed recent studies focused on assessing the relative roles of factors operating at different scales in shaping animal populations, species, communities, and individual behaviors. Our goal was to summarize the current state of the science by documenting trends and advances in approaches used to weigh the relative impact of drivers at different scales. We identify several recent advances in remote sensing–based data collection, such as unmanned aerial vehicles and terrestrial laser scanning, that have the potential to increase the range of scales over which more detailed measurements of the composition and structure of environments can be made. We also highlight the promise of experimental studies and specific statistical approaches for providing a more solid understanding of the relative importance of factors operating at different spatial scales. We found that after nearly three decades of studies focused on the relative importance of factors operating at different scales, no general pattern has emerged. There is no clear evidence that one scale or one set of scales consistently plays a larger role than others. Nonetheless, it is clear from this research that ecological processes are indeed affected by processes operating at multiple spatial scales. We conclude that a more productive line of questioning might focus not on the relative importance of factors operating at different scales, but on understanding which factors affect a given process, at what scales they operate, and how they interact.