| Species | Sites Reporting | Year |
|---|---|---|
| Monarch | 111 | 2003 |
| Cabbage White | 104 | 2003 |
| Common/Orange Sulphur | 90 | 2003 |
| Pearl Crescent | 86 | 2003 |
| Eastern Tiger Swallowtail | 86 | 2003 |
| Black Swallowtail | 78 | 2003 |
| Spring/Summer Azure | 73 | 2003 |
| Red Admiral | 70 | 2003 |
| Great Spangled Fritillary | 70 | 2003 |
| Eastern Tailed Blue | 69 | 2003 |
| Common Wood Nymph | 69 | 2003 |
| Little Wood Satyr | 62 | 2003 |
| Silver Spotted Skipper | 54 | 2003 |
| Mourning Cloak | 54 | 2003 |
| Red-Spotted Purple | 53 | 2003 |
| Viceroy | 47 | 2003 |
| American Painted Lady | 41 | 2003 |
| Eyed Brown | 39 | 2003 |
| Least Skipper | 36 | 2003 |
| European Skipper | 35 | 2003 |
| Peck's Skipper | 34 | 2003 |
| Eastern Comma | 27 | 2003 |
| Northern Pearly-eye | 27 | 2003 |
| Question Mark | 25 | 2003 |
| Tawny Edge | 21 | 2003 |
| Coral Hairstreak | 16 | 2003 |
| Delaware Skipper | 16 | 2003 |
| Buckeye | 15 | 2003 |
| Common Sootywing | 14 | 2003 |
| Silvery Checkerspot | 12 | 2003 |
| Black Dash | 12 | 2003 |
| Hobomok Skipper | 12 | 2003 |
| Dun Skipper | 12 | 2003 |
| Little Yellow | 10 | 2003 |
| Little Glassywing | 10 | 2003 |
| Spicebush Swallowtail | 9 | 2003 |
| Dion Skipper | 9 | 2003 |
| Giant Swallowtail | 9 | 2003 |
| Banded Hairstreak | 9 | 2003 |
| Wild Indigo Duskywing | 8 | 2003 |
| Hackberry Butterfly | 8 | 2003 |
| Bronze Copper | 8 | 2003 |
| Broken Dash | 7 | 2003 |
| Baltimore Checkerspot | 6 | 2003 |
| Aphrodite | 6 | 2003 |
| Mulberrywing | 6 | 2003 |
| Meadow Fritillary | 6 | 2003 |
| Appalachian Brown | 6 | 2003 |
| Fiery Skipper | 6 | 2003 |
| Zabulon Skipper | 6 | 2003 |
| Gray Hairstreak | 5 | 2003 |
| Crossline Skipper | 5 | 2003 |
| Roadside Skipper | 5 | 2003 |
| Juvenal's Duskywing | 4 | 2003 |
| Gray Comma | 4 | 2003 |
| Pipevine Swallowtail | 3 | 2003 |
| Checkered White | 3 | 2003 |
| Edwards Hairstreak | 3 | 2003 |
| Tawny Emperor | 3 | 2003 |
| Broadwinged Skipper | 3 | 2003 |
| Horace's Duskywing | 3 | 2003 |
| American Copper | 3 | 2003 |
| Long Dash | 3 | 2003 |
| Northern Cloudywing | 3 | 2003 |
| Snout Butterfly | 3 | 2003 |
| Cloudless Sulphur | 3 | 2003 |
| Purplish Copper | 2 | 2003 |
| Acadian Hairstreak | 2 | 2003 |
| Leonard's Skipper | 2 | 2003 |
| Regal Fritillary | 2 | 2003 |
| Sleepy Duskywing | 2 | 2003 |
| Southern Cloudywing | 2 | 2003 |
| Two Spot Skipper | 1 | 2003 |
| Variegated Fritillary | 1 | 2003 |
| Olympia Marble | 1 | 2003 |
| Silver-Bordered Fritillary | 1 | 2003 |
| Goatweed Butterfly | 1 | 2003 |
| Henry's Elfin | 1 | 2003 |
| Hoary Elfin | 1 | 2003 |
| Gorgone Checkerspot | 1 | 2003 |
| Checkered Skipper | 1 | 2003 |
| Dogface | 1 | 2003 |
| Dwarf Sulphur | 1 | 2003 |
| Hayhurst's Scallopwing | 1 | 2003 |
| Hoary Edge | 1 | 2003 |
| Zebra Swallowtail | 1 | 2003 |
| Sachem | 1 | 2003 |
| Striped Hairstreak | 1 | 2003 |
Illinois Butterfly Monitoring Network
The Illinois Butterfly Monitoring Network engages citizen scientists in the process of collecting quantitative data on butterfly populations.