60 birds were recorded seen in Wisconsin in September in our iNaturalist sample; 7 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top birds in September

Wild Turkey
Sandhill Crane

Mallard

Great Blue Heron

Tennessee Warbler
Canada Goose

American Goldfinch

Red-tailed Hawk

Ring-billed Gull

Ruby-throated Hummingbird

Black-capped Chickadee

Yellow-rumped Warbler
All birds seen in Wisconsin in September
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | Wild Turkey | Meleagris gallopavo | Pheasants, Grouse, and Allies | 695 | May (past peak) |
| 2 | Sandhill Crane | Antigone canadensis | Cranes | 594 | May (past peak) |
| 3 | Mallard | Anas platyrhynchos | Ducks, Geese, and Swans | 584 | Apr (past peak) |
| 4 | Great Blue Heron | Ardea herodias | Herons, Egrets, and Bitterns | 527 | Aug (past peak) |
| 5 | Tennessee Warbler | Leiothlypis peregrina | New World Warblers | 465 | Sep (peak) |
| 6 | Canada Goose | Branta canadensis | Ducks, Geese, and Swans | 457 | May (past peak) |
| 7 | American Goldfinch | Spinus tristis | Finches, Euphonias, and Allies | 391 | May (past peak) |
| 8 | Red-tailed Hawk | Buteo jamaicensis | Hawks, Eagles, and Kites | 374 | Sep (peak) |
| 9 | Ring-billed Gull | Larus delawarensis | Gulls, Terns, and Skimmers | 362 | Aug (past peak) |
| 10 | Ruby-throated Hummingbird | Archilochus colubris | Hummingbirds | 351 | Aug (past peak) |
| 11 | Black-capped Chickadee | Poecile atricapillus | Tits, Chickadees, and Titmice | 349 | Apr (past peak) |
| 12 | Yellow-rumped Warbler | Setophaga coronata | New World Warblers | 341 | Apr (past peak) |
| 13 | Bald Eagle | Haliaeetus leucocephalus | Hawks, Eagles, and Kites | 327 | May (past peak) |
| 14 | Blue Jay | Cyanocitta cristata | Crows, Jays, and Magpies | 321 | May (past peak) |
| 15 | Swainson's Thrush | Catharus ustulatus | Thrushes | 321 | Sep (peak) |
| 16 | Downy Woodpecker | Dryobates pubescens | Woodpeckers | 321 | Apr (past peak) |
| 17 | House Sparrow | Passer domesticus | Old World Sparrows | 306 | May (past peak) |
| 18 | Mourning Dove | Zenaida macroura | Pigeons and Doves | 285 | Apr (past peak) |
| 19 | Northern Flicker | Colaptes auratus | Woodpeckers | 280 | Apr (past peak) |
| 20 | Great Egret | Ardea alba | Herons, Egrets, and Bitterns | 248 | Aug (past peak) |
| 21 | Palm Warbler | Setophaga palmarum | New World Warblers | 248 | May (past peak) |
| 22 | Northern Cardinal | Cardinalis cardinalis | Cardinals and Allies | 247 | Apr (past peak) |
| 23 | American Redstart | Setophaga ruticilla | New World Warblers | 237 | May (past peak) |
| 24 | Double-crested Cormorant | Nannopterum auritum | Cormorants and Shags | 237 | Sep (peak) |
| 25 | Wood Duck | Aix sponsa | Ducks, Geese, and Swans | 233 | Apr (past peak) |
| 26 | Cedar Waxwing | Bombycilla cedrorum | Waxwings | 228 | Aug (past peak) |
| 27 | Magnolia Warbler | Setophaga magnolia | New World Warblers | 213 | May (past peak) |
| 28 | Nashville Warbler | Leiothlypis ruficapilla | New World Warblers | 209 | May (past peak) |
| 29 | Green Heron | Butorides virescens | Herons, Egrets, and Bitterns | 195 | Aug (past peak) |
| 30 | White-breasted Nuthatch | Sitta carolinensis | Nuthatches | 185 | Apr (past peak) |
| 31 | Common Yellowthroat | Geothlypis trichas | New World Warblers | 182 | May (past peak) |
| 32 | American Robin | Turdus migratorius | Thrushes | 175 | Apr (past peak) |
| 33 | Eastern Wood-Pewee | Contopus virens | Tyrant Flycatchers | 175 | Aug (past peak) |
| 34 | Turkey Vulture | Cathartes aura | New World Vultures | 173 | Apr (past peak) |
| 35 | Eastern Phoebe | Sayornis phoebe | Tyrant Flycatchers | 173 | Apr (past peak) |
| 36 | Trumpeter Swan | Cygnus buccinator | Ducks, Geese, and Swans | 169 | Jun (past peak) |
| 37 | Red-bellied Woodpecker | Melanerpes carolinus | Woodpeckers | 167 | May (past peak) |
| 38 | Gray Catbird | Dumetella carolinensis | Mockingbirds and Thrashers | 160 | May (past peak) |
| 39 | Cooper's Hawk | Astur cooperii | Hawks, Eagles, and Kites | 155 | Apr (past peak) |
| 40 | Red-eyed Vireo | Vireo olivaceus | Vireos, Shrike-Babblers, and Erpornis | 142 | May (past peak) |
| 41 | Belted Kingfisher | Megaceryle alcyon | Kingfishers | 139 | Apr (past peak) |
| 42 | Bay-breasted Warbler | Setophaga castanea | New World Warblers | 139 | Sep (peak) |
| 43 | Black-throated Green Warbler | Setophaga virens | New World Warblers | 136 | May (past peak) |
| 44 | Blackpoll Warbler | Setophaga striata | New World Warblers | 132 | May (past peak) |
| 45 | American White Pelican | Pelecanus erythrorhynchos | Pelicans | 130 | Apr (past peak) |
| 46 | Red-breasted Nuthatch | Sitta canadensis | Nuthatches | 129 | Sep (peak) |
| 47 | Yellow-bellied Sapsucker | Sphyrapicus varius | Woodpeckers | 129 | Apr (past peak) |
| 48 | Song Sparrow | Melospiza melodia | New World Sparrows | 127 | May (past peak) |
| 49 | Cape May Warbler | Setophaga tigrina | New World Warblers | 127 | Sep (peak) |
| 50 | Chestnut-sided Warbler | Setophaga pensylvanica | New World Warblers | 127 | May (past peak) |