Insect · GBIF taxon 4301148
Army Cutworm Moth
Euxoa auxiliarisAlso known as Miller Moth, Army Cutworm
Army cutworm moths execute one of North America's most impressive insect migrations, traveling hundreds of miles from lowland plains to alpine talus slopes every summer. High in the Rocky Mountains, millions of adults aggregate under mountain boulders to estivate through the hottest months, providing a vital, fat-rich food source for foraging grizzly bears. In autumn, adults descend back to prairies and croplands to lay eggs, where subterranean larvae overwinter before emerging to feed on young crops in spring.
MigratoryNight ActiveAgricultural Insect
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & prey
- Flower Nectar
- Wheat
- Alfalfa
Predators
- Grizzly Bear
- Little Brown Bat
- Mountain Bluebird
ThreatsPesticide applications and loss of alpine snowpack habitats
HabitatsAgricultural fields, grasslands, montane forests, alpine talus slopes
Life span1 year
Size / weightNot available
Classification
- OrderLepidoptera
- FamilyNoctuidae
- GenusEuxoa
- SpeciesEuxoa auxiliaris
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Safe to observe at a normal distance.
Responsible observation
- Observation: Watch for dense swarms around outdoor lights during late spring and early autumn migrations.
- Grizzly Safety: Avoid approaching high-elevation alpine talus fields in summer where massed moths draw feeding bears.
- Home Exclusion: Keep porch lights off and seal window screens to prevent adults from entering living spaces.
Predator (c) Nathan Ruser, some rights reserved (CC BY), uploaded by Nathan Ruser · cc-by
Competitor Ecological Counterpart 
Close Relative (c) SteveM4560, some rights reserved (CC BY), uploaded by SteveM4560 · cc-by
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Found in Collections
Species set
Moonlight Marvels
Army Cutworm Moth is found in this collection. Identify it in Fauna to fill this slot and continue your progress.
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