Adults can be found in virtually any habitat, ranging from rural to urban, subtropcis to tundra. They prefer to drink sap from trees, liquid from rotting fruit and bird droppings. They will drink nectar from milkweed, clover, aster and alfalfa flowers if their preferred foods are not available. Males are active in the mid-afternoon to evening, looking for females. They dart out at approaching objects, quick to defend their territories from any living creature. Females lay a single fertilized egg on a leaf of the larval host plants. Caterpillars eat the leaves of nettles, false nettles, mamaki, pellitories from the aster family and other related plants. Once caterpillars hatch, they form a retreat of folded leaves and silk. The caterpillars are black, developing white, or light yellow, speckles all over the body. Several black, branched spines radiate from each segment; these spines may be white closer to the rear of the larva. There are seven yellow bands, bent into the shape of upside-down 'V's, that mark each segment along the sides from head to rear.