Monarch butterflies undergo one of nature's most remarkable migrations, and their welfare is threatened by habitat loss, pesticides, and climate change.
While insect sentience is debated, monarchs have nervous systems capable of pain-like responses and complex navigation. Their welfare matters both individually and as a population. Loss of milkweed forces adult females to deplete energy reserves searching for oviposition sites. Pesticide exposure causes neurological effects. Loss of overwintering habitat means millions die from cold exposure. Climate change shifts their timing out of synchrony with host plants.