| Species | Sites Reporting | Year |
|---|---|---|
| Cabbage White | 35 | 1994 |
| Monarch | 35 | 1994 |
| Common/Orange Sulphur | 33 | 1994 |
| Pearl Crescent | 30 | 1994 |
| Common Wood Nymph | 28 | 1994 |
| Eastern Tiger Swallowtail | 28 | 1994 |
| Spring/Summer Azure | 27 | 1994 |
| Red Admiral | 26 | 1994 |
| Black Swallowtail | 25 | 1994 |
| Eastern Tailed Blue | 24 | 1994 |
| Great Spangled Fritillary | 23 | 1994 |
| Red-Spotted Purple | 23 | 1994 |
| Little Wood Satyr | 22 | 1994 |
| European Skipper | 22 | 1994 |
| Viceroy | 22 | 1994 |
| Mourning Cloak | 21 | 1994 |
| Eyed Brown | 18 | 1994 |
| Least Skipper | 17 | 1994 |
| Silver Spotted Skipper | 16 | 1994 |
| Question Mark | 16 | 1994 |
| Peck's Skipper | 14 | 1994 |
| Hobomok Skipper | 13 | 1994 |
| Tawny Edge | 12 | 1994 |
| Northern Pearly-eye | 12 | 1994 |
| Buckeye | 11 | 1994 |
| Delaware Skipper | 11 | 1994 |
| American Painted Lady | 10 | 1994 |
| Eastern Comma | 10 | 1994 |
| Banded Hairstreak | 9 | 1994 |
| Silvery Checkerspot | 9 | 1994 |
| Dun Skipper | 9 | 1994 |
| Black Dash | 8 | 1994 |
| Wild Indigo Duskywing | 8 | 1994 |
| American Copper | 8 | 1994 |
| Crossline Skipper | 8 | 1994 |
| Coral Hairstreak | 8 | 1994 |
| Aphrodite | 7 | 1994 |
| Mulberrywing | 7 | 1994 |
| Acadian Hairstreak | 7 | 1994 |
| Little Yellow | 6 | 1994 |
| Bronze Copper | 6 | 1994 |
| Silver-Bordered Fritillary | 5 | 1994 |
| Baltimore Checkerspot | 5 | 1994 |
| Checkered Skipper | 5 | 1994 |
| Common Sootywing | 5 | 1994 |
| Hackberry Butterfly | 5 | 1994 |
| Long Dash | 5 | 1994 |
| Snout Butterfly | 5 | 1994 |
| Northern Cloudywing | 5 | 1994 |
| Broken Dash | 5 | 1994 |
| Dion Skipper | 4 | 1994 |
| Little Glassywing | 4 | 1994 |
| Gray Hairstreak | 4 | 1994 |
| Two Spot Skipper | 3 | 1994 |
| Spicebush Swallowtail | 3 | 1994 |
| Juvenal's Duskywing | 3 | 1994 |
| Hickory Hairstreak | 3 | 1994 |
| Roadside Skipper | 3 | 1994 |
| Cloudless Sulphur | 3 | 1994 |
| Northern Hairstreak | 3 | 1994 |
| Broadwinged Skipper | 3 | 1994 |
| Variegated Fritillary | 3 | 1994 |
| Edwards Hairstreak | 3 | 1994 |
| Tawny Emperor | 3 | 1994 |
| Dwarf Sulphur | 2 | 1994 |
| Regal Fritillary | 2 | 1994 |
| Meadow Fritillary | 2 | 1994 |
| Zabulon Skipper | 2 | 1994 |
| Pipevine Swallowtail | 2 | 1994 |
| Dogface | 2 | 1994 |
| Milbert's Tortoiseshell | 2 | 1994 |
| Fiery Skipper | 2 | 1994 |
| Checkered White | 2 | 1994 |
| Giant Swallowtail | 2 | 1994 |
| Zebra Swallowtail | 2 | 1994 |
| Striped Hairstreak | 2 | 1994 |
| Purplish Copper | 1 | 1994 |
| Olympia Marble | 1 | 1994 |
| Appalachian Brown | 1 | 1994 |
| Hoary Elfin | 1 | 1994 |
| Southern Cloudywing | 1 | 1994 |
| Dreamy Duskywing | 1 | 1994 |
| Mottled Duskywing | 1 | 1994 |
| Great Gray Copper | 1 | 1994 |
| Leonard's Skipper | 1 | 1994 |
| Hayhurst's Scallopwing | 1 | 1994 |
| Indian Skipper | 1 | 1994 |
| White-M Hairstreak | 1 | 1994 |
| Marine Blue | 1 | 1994 |
| Henry's Elfin | 1 | 1994 |
| Sachem | 1 | 1994 |
| Gorgone Checkerspot | 1 | 1994 |
Illinois Butterfly Monitoring Network
The Illinois Butterfly Monitoring Network engages citizen scientists in the process of collecting quantitative data on butterfly populations.