Biodiversity in Ethiopia is under mounting pressure from deforestation, agricultural expansion, climate change, and other anthropogenic pressures, yet conventional conservation approaches often fail to protect species and ecosystems effectively. Dominated by Western scientific paradigms, these approaches treat the ecosystems as isolated from human activity, relying on centralized management, protected areas, and technical interventions. In human-dominated landscapes, such models frequently overlook the adaptive capacities embedded within Indigenous Knowledge (IK) systems. Developed through generations of observation, experimentation, and social regulation, IK encodes a detailed understanding of species behavior, landscape dynamics, and sustainable resource use, functioning as a dynamic ecological system. This essay argues that integrating Indigenous knowledge into biodiversity conservation is an Ecological imperative rather than a moral preference. Evidence from Ethiopian church forests, pastoralist rangelands, and Konso terraces shows that IK sustains biodiversity, ecosystem resilience, and livelihoods. While highly effective, IK is not uniform or universally sufficient; demographic change, market pressures, and internal social inequalities can constrain its impact. Recognizing both the strengths and limits of IK, and embedding it within multi-level governance systems is essential for designing resilient, socially legitimate conservation strategies. Thoughtful integration transforms Indigenous stewardship from a cultural practice into a strategic tool for sustaining ecosystems in climatically variable, human-occupied landscapes.