33 butterflies were recorded flying in District of Columbia in April in our iNaturalist sample; 6 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top butterflies in April

Small White

Eastern Tiger Swallowtail

Eastern Tailed-Blue

Eastern Comma

Pearl Crescent

Question Mark

Zebra Swallowtail

American Lady

Red Admiral

Spicebush Swallowtail

Monarch

Juvenal's Duskywing
All butterflies flying in District of Columbia in April
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | Small White | Pieris rapae | Whites, Yellows, and Sulphurs | 53 | Jun (rising) |
| 2 | Eastern Tiger Swallowtail | Papilio glaucus | Swallowtails and Parnassians | 50 | Aug (rising) |
| 3 | Eastern Tailed-Blue | Everes comyntas | Gossamer-winged Butterflies | 48 | Sep (rising) |
| 4 | Eastern Comma | Polygonia comma | Brush-footed Butterflies | 33 | Apr (peak) |
| 5 | Pearl Crescent | Phyciodes tharos | Brush-footed Butterflies | 29 | Sep (rising) |
| 6 | Question Mark | Polygonia interrogationis | Brush-footed Butterflies | 20 | May (rising) |
| 7 | Zebra Swallowtail | Eurytides marcellus | Swallowtails and Parnassians | 14 | Jul (rising) |
| 8 | American Lady | Vanessa virginiensis | Brush-footed Butterflies | 12 | May (rising) |
| 9 | Red Admiral | Vanessa atalanta | Brush-footed Butterflies | 12 | Jul (rising) |
| 10 | Spicebush Swallowtail | Papilio troilus | Swallowtails and Parnassians | 10 | Aug (rising) |
| 11 | Monarch | Danaus plexippus | Brush-footed Butterflies | 9 | Sep (rising) |
| 12 | Juvenal's Duskywing | Erynnis juvenalis | Skippers | 9 | Apr (peak) |
| 13 | Falcate Orangetip | Anthocharis midea | Whites, Yellows, and Sulphurs | 9 | Apr (peak) |
| 14 | Silver-spotted Skipper | Epargyreus clarus | Skippers | 9 | Aug (rising) |
| 15 | Mourning Cloak | Nymphalis antiopa | Brush-footed Butterflies | 8 | Mar (past peak) |
| 16 | Orange Sulphur | Colias eurytheme | Whites, Yellows, and Sulphurs | 8 | Oct (rising) |
| 17 | Wild Indigo Duskywing | Erynnis baptisiae | Skippers | 7 | Sep (rising) |
| 18 | White M Hairstreak | Parrhasius m-album | Gossamer-winged Butterflies | 5 | Apr (peak) |
| 19 | Pipevine Swallowtail | Battus philenor | Swallowtails and Parnassians | 3 | Sep (rising) |
| 20 | Red-spotted Admiral | Limenitis arthemis | Brush-footed Butterflies | 3 | Aug (rising) |
| 21 | Red-banded Hairstreak | Calycopis cecrops | Gossamer-winged Butterflies | 3 | Aug (rising) |
| 22 | Common Checkered-Skipper | Burnsius communis | Skippers | 3 | Oct (rising) |
| 23 | Gray Hairstreak | Strymon melinus | Gossamer-winged Butterflies | 2 | Sep (rising) |
| 24 | Harvester | Feniseca tarquinius | Gossamer-winged Butterflies | 2 | Apr (peak) |
| 25 | Zabulon Skipper | Lon zabulon | Skippers | 2 | Aug (rising) |
| 26 | Painted Lady | Vanessa cardui | Brush-footed Butterflies | 1 | Sep (rising) |
| 27 | Black Swallowtail | Papilio polyxenes | Swallowtails and Parnassians | 1 | Jul (rising) |
| 28 | Clouded Sulphur | Colias philodice | Whites, Yellows, and Sulphurs | 1 | Oct (rising) |
| 29 | American Snout | Libytheana carinenta | Brush-footed Butterflies | 1 | May (rising) |
| 30 | Meadow Fritillary | Boloria bellona | Brush-footed Butterflies | 1 | Apr (peak) |
| 31 | Silvery Checkerspot | Chlosyne nycteis | Brush-footed Butterflies | 1 | Jul (rising) |
| 32 | Sleepy Orange | Eurema nicippe | Whites, Yellows, and Sulphurs | 1 | Aug (rising) |
| 33 | Huron Skipper | Atalopedes huron | Skippers | 1 | Sep (rising) |