Trophic hotspots as a perspective for understanding and managing ecosystem function.

The functions of ecosystems emerge from dynamic environments characterized by spatiotemporal heterogeneity, especially in the distribution of nutrients and organisms. This heterogeneity results in the emergence of biological hotspots, localized regions with disproportionate contributions to ecosystem functioning and biodiversity globally. While traditional hotspot approaches (for example, biodiversity hotspots) rely on static boundaries of high species endemism, trophic hotspots are highly dynamic, emerging from the localized concentration, mobilization and propagation of energy or limiting nutrients across landscapes through the foraging movements of diverse consumer taxa. Here we synthesize theory across community, foraging and food web ecologies to present trophic hotspots as a useful entry point towards studying and understanding cross-scale processes in ecology. We contend that the mechanisms that generate trophic hotspots, from marine upwellings and mineral licks to mass animal migrations, result from the same fundamental processes across ecosystems. Importantly, these hotspots reflect a critical form of spatiotemporal heterogeneity that contributes to the maintenance of function in the face of perturbations (that is, resilience). Finally, we argue that trophic hotspots represent valuable focal points for the proactive conservation and management of ecological systems in a rapidly changing world.