Based on 2,911 research-grade iNaturalist observations in Colorado, Two-tailed Swallowtail is most often recorded in July; in Colorado it behaves like a summer visitor / breeder. It ranks #3 among butterflies recorded in the state in our data.
Papilio multicaudata
Two-tailed Swallowtail in Colorado by month
Bars show research-grade observations per month. They mix true seasonality with how often people are outdoors, so treat small numbers with caution.
Also seen in Colorado in July
Weidemeyer's Admiral
Taxiles Skipper
Rocky Mountain Parnassian
Monarch
Variegated Fritillary
Western Tiger Swallowtail
Painted Lady
Small White
Places to look in Colorado
National ForestWhite River National Forest
Botanical GardenDenver Botanic Gardens
National ForestRio Grande National Forest
National ForestSan Juan National Forest
State ParkRoxborough State Park
State ParkMancos State Park
FAQ
When does Two-tailed Swallowtail appear in Colorado?
Mainly June–August, with the most records in July.
How common is Two-tailed Swallowtail in Colorado?
It ranks #3 by number of iNaturalist observations among butterflies in Colorado (2,911 records in our sample).