Monarch butterfly populations have declined dramatically due to milkweed loss, and large-scale milkweed restoration programs are essential for population recovery and individual welfare.
Whether insects experience welfare in a morally relevant sense is scientifically and philosophically contested, but the precipitous decline of monarch populations represents a loss of enormous biological richness and raises questions about the scale of suffering involved if insects do have morally relevant experiences. From a conservative welfare perspective, the extraordinary scale of monarch mortality — billions of individuals across the annual cycle — warrants precautionary concern. More broadly, milkweed restoration benefits not only monarchs but the entire community of native plants, pollinators, and wildlife dependent on the same habitat. Advocacy for milkweed restoration and against unnecessary herbicide use serves both ecological and potentially welfare goals across a vast number of organisms.