Tropical deforestation induces thresholds of reproductive viability and habitat suitability in Earth’s largest eagles

Abstract Apex predators are threatened globally, and their local extinctions often driven by failures in sustaining prey acquisition under contexts of severe scarcity. The harpy eagle Harpia harpyja is Earth’s largest the apex aerial predator Amazonian forests, but no previous study has examined impact forest loss on feeding ecology. We monitored 16 active nests embedded within landscapes that had experienced 0 to 85% loss, identified 306 captured items. Harpy eagles could not switch open-habitat deforested habitats, retained a diet based canopy vertebrates even landscapes. Feeding rates decreased with three fledged individuals dying starvation succumbed 50–70% deforestation. Because > 70% supported nests, eaglets be provisioned independence 50% we established cover threshold for reproductive viability pairs. Our scaling-up estimate indicates 35% entire 428,800-km 2 ‘Arc Deforestation’ region cannot support breeding populations. results suggest restoring population highly fragmented critically depends decisive conservation action.