Fauna
Insect

Spongy Moth

Lymantria dispar

Also known as Gypsy Moth, European Gypsy Moth, Asian Gypsy Moth

Spongy moths are infamous forest defoliators whose hairy caterpillars feature a distinctive pattern of five pairs of blue spots followed by six pairs of red spots along their backs. Adult females are buff-white and largely flightless, while smaller mottled brown males fly actively in search of mates using large feathered antennae. During population surges, millions of caterpillars strip entire forest canopies bare before laying tan, felt-like egg masses on tree trunks and outdoor structures.

InvasiveForest PestDefoliator
Spongy Moth reference1 / 7
(c) Patrick Hanly, some rights reserved (CC BY), uploaded by Patrick Hanly · cc-by
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Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Key facts
Diet & preyOak Leaves, Willow Leaves, Aspen Leaves
Predators
  • White-Footed Mouse
  • Black-Capped Chickadee
  • Cuckoo Birds
ThreatsNucleopolyhedrovirus, Entomophaga maimaiga fungus, parasitoid wasps, and bird predation
HabitatsDeciduous forests, mixed woodlands, parks, and suburban neighborhoods
Life span1–2 weeks as adults; 1 year total cycle
Classification
  1. OrderLepidoptera
  2. FamilyErebidae
  3. GenusLymantria
  4. SpeciesLymantria dispar
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Caterpillar hairs cause itchy skin rashes; avoid handling caterpillars or egg masses with bare hands.
Why it is dangerous
Caterpillars possess stinging hairs containing histamine-like chemicals that trigger contact dermatitis and skin rashes.
How to recognize a risky encounter
Look for dark hairy caterpillars with five pairs of blue spots followed by six pairs of red spots along the back.
What to do
Avoid bare skin contact with larvae or egg masses; wear gloves and long sleeves when removing them from property.
Responsible observation
  • Spotting Egg Masses: Look for tan, sponge-like patches on tree bark and outdoor gear during autumn and winter.
  • Avoid Touching: Do not handle caterpillars or egg masses without gloves, as shed hairs cause skin irritation.
  • Prevent Spread: Inspect vehicles, trailers, and firewood before traveling to uninfested forest regions.
Related species
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Found in Collections

Species set

Moonlight Marvels

Spongy Moth is found in this collection. Identify it in Fauna to fill this slot and continue your progress.

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