Monarch butterflies have declined by over 80% in recent decades. While insect welfare is debated, the scale of population collapse and its ecosystem consequences warrant serious attention.
Whether insects like monarchs experience welfare in a morally relevant sense is scientifically uncertain — but the scale of their decline and their ecological role in supporting animal species whose sentience is less disputed makes monarch conservation highly relevant to animal welfare. Pollinators support the food webs that sustain vertebrate wildlife. Neonicotinoid exposure at sub-lethal doses impairs navigation in ways that may prevent monarchs from completing their migration — a failure that constitutes harm regardless of whether subjective suffering is involved. Habitat loss, climate change, and pesticide exposure together create a crisis that demands urgent individual and policy response.