Abstract: The increasing effects of climate change and other local human-induced stressors are rapidly altering ecosystem function worldwide. Changes in ecosystem function can be tracked using trait-based approaches, whereby species traits closely linked to key functional roles and environmental tolerance are measured to estimate community functional diversity, composition, and resilience. While trait-based methods have been increasingly applied to provide retrospective insight on historical or long-term ecosystem degradation, few studies have explored the use of traits prospectively to map ecosystem recovery though management techniques, like restoration, currently at the forefront of conservation. In particular, coral reef restoration, which facilitates coral population growth by replanting nursery-reared hard coral species, is a relatively new field that can offer insight on the application of trait-based approaches to evaluate and optimize ecosystem recovery. Here, we apply trait-based methods to global datasets of reef composition, coral restoration, human stressors from >4,700 reefs to quantify and identify ecological (e.g. coral functional traits) and environmental factors (e.g. coastal development) that predict restoration success. We then use these predictors to forecast where local conditions will best facilitate functional recovery in coral reefs via restoration to help inform future restoration site selection and design. Our results show that stress-sensitive coral species are being replanted at reefs exposed to chronic environmental stress, possibly limiting functional recovery. Additionally, our findings identify degraded sites with more stable climates where active restoration could restore ecological function. Further monitoring at these reef sites will allow practitioners to ground-truth the utility of trait-based approaches for informing likely outcomes of local restoration projects. Results from this study can inform a global framework for restoration action that establishes target regions and reefs where restoration can be used to rebuild reef function and strengthen resilience under climate change. In combination with local conservation measures and global action against climate change, effective restoration practices that apply trait-based methods could be key to preserving coastal ecosystem processes and functions.
