Black Swallowtail (Papilio polyxenes) is in the Swallowtails and Parnassians family (Papilionidae). Across the U.S., iNaturalist users have logged 71,351 research-grade observations of it in our sample, peaking in August.
Seasonal pattern in the national data: summer visitor / breeder. Counts also reflect when people are out photographing, so compare months within a state rather than across states.
When to photograph Black Swallowtail: observations by month (U.S.)
About Black Swallowtail
Papilio polyxenes, the (eastern) black swallowtail, American swallowtail or parsnip swallowtail, is a butterfly found throughout much of North America. It is the state butterfly of Oklahoma and New Jersey. An extremely similar-appearing species, Papilio joanae, occurs in the Ozark Mountains region, but it appears to be closely related to Papilio machaon, rather than P. polyxenes. The species is named after the figure in Greek mythology, Polyxena (pron.: /pəˈlɪksɨnə/; Greek: Πολυξένη), who was the youngest daughter...From Wikipedia via iNaturalist — article, CC BY-SA.
Black Swallowtail by state
| State | Observations | Peak month | Main season |
|---|---|---|---|
| Texas | 19,784 | May | Apr–Jul |
| Illinois | 7,194 | July | Jun–Sep |
| Ohio | 6,233 | August | Jun–Sep |
| New York | 5,963 | August | Jun–Sep |
| Pennsylvania | 4,454 | August | Jun–Sep |
| Maryland | 3,397 | August | Jun–Sep |
| Virginia | 3,148 | August | May–Oct |
| Michigan | 2,571 | July | Jun–Sep |
| New Jersey | 2,277 | August | Jun–Sep |
| Minnesota | 2,104 | July | Jun–Sep |
| Wisconsin | 2,086 | August | Jun–Sep |
| Missouri | 1,848 | September | Jun–Sep |
| Indiana | 1,597 | August | Jul–Sep |
| Oklahoma | 1,586 | August | Apr–Sep |
| Kansas | 1,096 | August | Jun–Sep |
| Nebraska | 966 | July | Jun–Sep |
| New Mexico | 873 | July | Jun–Aug |
| Iowa | 858 | August | Jun–Sep |
| Colorado | 727 | July | Jun–Sep |
| Arizona | 616 | September | May–Oct |
| Connecticut | 314 | August | Jun–Sep |
| Mississippi | 210 | June | Jun–Sep |
| Florida | 179 | September | May–Sep |
| South Dakota | 170 | August | Jul–Sep |
| West Virginia | 163 | August | Jul–Sep |
| Louisiana | 155 | May | Apr–Jul |
| Arkansas | 135 | August | Jul–Sep |
| Massachusetts | 94 | September | May–Oct |
| North Carolina | 94 | August | Aug–Oct |
| Vermont | 60 | August | Jul–Sep |
| Tennessee | 48 | August | Jul–Sep |
| Kentucky | 44 | August | Aug–Sep |
| District of Columbia | 43 | July | May–Oct |
| North Dakota | 43 | August | Jul–Sep |
| South Carolina | 37 | August | Jul–Sep |
| Delaware | 36 | September | Aug–Oct |
| Maine | 31 | August | Jun–Aug |
| Georgia | 30 | September | Jun–Oct |
| Alabama | 27 | August | May–Sep |
| California | 25 | April | Mar–Jun |
| New Hampshire | 13 | July | Jul–Sep |
| Nevada | 9 | September | Sep–Sep |
| Rhode Island | 7 | July | Jul–Oct |
Main season = months with at least 30% of the state's peak-month count.
Related butterflies (Swallowtails and Parnassians)
Eastern Tiger Swallowtail
Pipevine Swallowtail
Spicebush Swallowtail
Eastern Giant Swallowtail
Western Tiger Swallowtail
Zebra Swallowtail
Anise Swallowtail
Western Giant Swallowtail
Photography tips
- Butterflies are sluggish on cool mornings — the best time for close approaches.
- Keep the sensor parallel to the wings for edge-to-edge sharpness.
- Nectar plants in bloom are reliable places to wait.
FAQ
When is the best time to photograph Black Swallowtail?
Nationally, August has the most observations, with the main season from April to September.
Where is Black Swallowtail most often seen?
The most observations come from Texas, Illinois, Ohio.