Don’t Touch These If You See Them on Your Plants: Meet the Mourning Cloak Butterfly Eggs That Look Like Alien Art

Don’t Touch These If You See Them on Your Plants: Meet the Mourning Cloak Butterfly Eggs That Look Like Alien Art

In the intricate world of gardening, it’s easy to mistake the strange for the harmful. That’s why many people instinctively scrape away unusual bumps, eggs, or insect clusters on their plants without a second thought. But if you happen to find tiny, metallic-looking, alien-esque clusters on the branches of your trees or shrubs — pause before you act. You may have stumbled upon the ethereal beginning of one of North America’s most stunning native butterflies: the Mourning Cloak (Nymphalis antiopa). These eggs may look bizarre, even threatening, but in reality, they’re precious little masterpieces of nature.

What Are Mourning Cloak Butterfly Eggs?

Mourning Cloak butterfly eggs are small, round, and laid in tight, uniform clusters around twigs or branches. They often shimmer with iridescent tones — bronze, copper, or silver — making them resemble tiny alien ornaments. Each egg is ribbed with vertical lines and often has a central depression at the top. Their strange appearance often leads people to think they’re the eggs of harmful pests, but they are far from it.

These eggs are typically laid by the female Mourning Cloak in early spring or summer. The butterfly prefers deciduous trees like willow, elm, hackberry, and poplar. The adult female lays rows of eggs in rings around tender twigs, ensuring that the newly hatched caterpillars will have access to fresh leaves.

Why You Shouldn’t Remove or Destroy Them

They’re Harmless to Your Plants: Mourning Cloak caterpillars may nibble on the leaves, but they don’t pose any serious threat to the health of mature trees.
They’re Ecologically Important: As native pollinators and a vital food source for birds, Mourning Cloaks play an essential role in the ecosystem.
They’re Rarely Seen: These butterflies are not as common as other species, and their numbers can be impacted by habitat destruction and pesticide use.
They’re Beautiful: Mourning Cloaks are striking butterflies with deep burgundy wings edged in pale yellow and dotted with blue — seeing them in flight is an unforgettable experience.