Mourning Cloak Butterflies: Early Spring Harbingers

The mourning cloak (Nymphalis antiopa) emerges from hibernation on the first warm April day, often before any flowers bloom. These long-lived butterflies (10 months as adults) seek sap flows from trees—maples are favorites—since nectar isn't yet available. Multiple cloaks may gather at a single tree wound.

Family: Nymphalidae (brush-footed)
Latin name: Nymphalis antiopa
Common name: Mourning cloak; caterpillars: spiny elm caterpillars
Distribution: North America (incl. Mexico), Europe
Habitat: Woodlands, wetland edges, gardens, meadows, prairies, old fields, farms

When to Spot Them

In the upper Midwest/Great Lakes, among the first spring butterflies—late March in warm springs, typically April. Seen again in fall after summer dormancy.

Ecological Role

Not frequent flower visitors, but summer/fall generations visit flowers and may pollinate.

Identification

Adults: Medium-large, 2.3–4 inch wingspan. Interior wings dark brown with yellow/cream border and blue submarginal spots. Exterior wings dark gray-brown with cream/yellow border.

Caterpillars: Black with long vertical/lateral spines (deter predators). Eight orange-red spots on thorax/abdomen, white speckles. Feed in large groups; thrash if provoked. Pupate away from host plant.

Attracting Them

Pesticide-Free Yard

No insecticides, especially on flowers or host plants.

Larval Host Plants

Caterpillars eat woody plant foliage: willow (Salix spp.), poplar (Populus spp.), less often elm (Ulmus), hackberry (Celtis occidentalis), birch (Betula). Females lay large egg clusters on stems.

Adult Forage

Spring: Sap of maple, poplar, birch; cherry/plum and willow flowers.
Summer: Black-eyed Susan, milkweed, yarrow, phlox; sap from sapsucker-damaged trees (mountain ash, maple, poplar).
Late summer/fall: Goldenrod.

Life Cycle

Overwinter as adults in insulated spots (behind bark, tree cavities). Emerge, bask, mate, seek sap/nectar. Eggs laid on woody stems (often willow). Hatch in ~10 days; caterpillars feed in aggregations, five instars, four molts. Pupate early June (north), hanging from branches. First adults emerge mid-late June/early July, forage briefly, then dormancy through August. Emerge September, fly warm fall days, then find overwintering sites.