Mourning cloak butterfly

Woodlands, forest edges, parks, gardens, and stream corridors across much of the Northern Hemisphere. Adults often bask on tree trunks, rocks, or flowers.

Adults feed mainly on tree sap, rotting fruit, and occasionally nectar; the pictured individual is visiting a flower. Caterpillars eat leaves of willow, elm, birch, poplar, and related trees.

Strong, erratic fliers that overwinter as adults and emerge early in spring. Caterpillars are gregarious when young, while adults defend territories and may live for many months.

Harmless to people and plants as adults; caterpillars rarely cause significant defoliation. They contribute to pollination and serve as prey for birds and other wildlife.