Monarch butterfly populations have declined dramatically, with their iconic multi-generational migration under threat from milkweed loss, pesticides, and climate disruption affecting millions of individual insects.
The moral status of butterfly welfare is uncertain, but the collapse of monarch populations represents a welfare-relevant event for the ecosystem. If butterflies have any capacity for welfare-relevant experience during their extraordinary migrations, the disruption of the cues and resources they evolved to depend on creates real challenges. More broadly, monarch decline cascades through food webs affecting birds, insects, and plants that depend on the pollination and ecological services monarchs provide. Habitat restoration through milkweed planting, pesticide reduction, and overwintering forest protection address both potential individual welfare and the ecological welfare of dependent communities.