60 birds were recorded seen in Indiana in September in our iNaturalist sample; 10 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top birds in September

Ruby-throated Hummingbird

Great Blue Heron

House Sparrow

Mourning Dove

Tennessee Warbler

American Goldfinch
Bay-breasted Warbler
Canada Goose

Northern Cardinal

Mallard

Great Egret

Turkey Vulture
All birds seen in Indiana in September
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | Ruby-throated Hummingbird | Archilochus colubris | Hummingbirds | 378 | Sep (peak) |
| 2 | Great Blue Heron | Ardea herodias | Herons, Egrets, and Bitterns | 368 | May (past peak) |
| 3 | House Sparrow | Passer domesticus | Old World Sparrows | 319 | Apr (past peak) |
| 4 | Mourning Dove | Zenaida macroura | Pigeons and Doves | 306 | Apr (past peak) |
| 5 | Tennessee Warbler | Leiothlypis peregrina | New World Warblers | 279 | Sep (peak) |
| 6 | American Goldfinch | Spinus tristis | Finches, Euphonias, and Allies | 277 | Aug (past peak) |
| 7 | Bay-breasted Warbler | Setophaga castanea | New World Warblers | 276 | Sep (peak) |
| 8 | Canada Goose | Branta canadensis | Ducks, Geese, and Swans | 254 | Apr (past peak) |
| 9 | Northern Cardinal | Cardinalis cardinalis | Cardinals and Allies | 246 | Apr (past peak) |
| 10 | Mallard | Anas platyrhynchos | Ducks, Geese, and Swans | 242 | Apr (past peak) |
| 11 | Great Egret | Ardea alba | Herons, Egrets, and Bitterns | 206 | Sep (peak) |
| 12 | Turkey Vulture | Cathartes aura | New World Vultures | 203 | Apr (past peak) |
| 13 | Red-tailed Hawk | Buteo jamaicensis | Hawks, Eagles, and Kites | 201 | Sep (peak) |
| 14 | Swainson's Thrush | Catharus ustulatus | Thrushes | 191 | May (past peak) |
| 15 | Downy Woodpecker | Dryobates pubescens | Woodpeckers | 178 | Apr (past peak) |
| 16 | Cape May Warbler | Setophaga tigrina | New World Warblers | 165 | Sep (peak) |
| 17 | Black-throated Green Warbler | Setophaga virens | New World Warblers | 162 | Sep (peak) |
| 18 | American Redstart | Setophaga ruticilla | New World Warblers | 160 | May (past peak) |
| 19 | Wild Turkey | Meleagris gallopavo | Pheasants, Grouse, and Allies | 144 | May (past peak) |
| 20 | Red-shouldered Hawk | Buteo lineatus | Hawks, Eagles, and Kites | 142 | May (past peak) |
| 21 | Green Heron | Butorides virescens | Herons, Egrets, and Bitterns | 140 | Aug (past peak) |
| 22 | White-breasted Nuthatch | Sitta carolinensis | Nuthatches | 134 | Apr (past peak) |
| 23 | American Robin | Turdus migratorius | Thrushes | 132 | Apr (past peak) |
| 24 | Double-crested Cormorant | Nannopterum auritum | Cormorants and Shags | 130 | Sep (peak) |
| 25 | Magnolia Warbler | Setophaga magnolia | New World Warblers | 128 | May (past peak) |
| 26 | Blue Jay | Cyanocitta cristata | Crows, Jays, and Magpies | 127 | May (past peak) |
| 27 | Ovenbird | Seiurus aurocapilla | New World Warblers | 120 | Sep (peak) |
| 28 | Wood Duck | Aix sponsa | Ducks, Geese, and Swans | 116 | Apr (past peak) |
| 29 | Cooper's Hawk | Astur cooperii | Hawks, Eagles, and Kites | 114 | Apr (past peak) |
| 30 | Red-bellied Woodpecker | Melanerpes carolinus | Woodpeckers | 112 | Apr (past peak) |
| 31 | Northern Flicker | Colaptes auratus | Woodpeckers | 103 | Apr (past peak) |
| 32 | Bald Eagle | Haliaeetus leucocephalus | Hawks, Eagles, and Kites | 102 | Apr (past peak) |
| 33 | Black-and-white Warbler | Mniotilta varia | New World Warblers | 95 | Sep (peak) |
| 34 | Eastern Wood-Pewee | Contopus virens | Tyrant Flycatchers | 94 | May (past peak) |
| 35 | Cedar Waxwing | Bombycilla cedrorum | Waxwings | 91 | May (past peak) |
| 36 | Killdeer | Charadrius vociferus | Plovers and Lapwings | 90 | May (past peak) |
| 37 | Common Yellowthroat | Geothlypis trichas | New World Warblers | 90 | May (past peak) |
| 38 | House Finch | Haemorhous mexicanus | Finches, Euphonias, and Allies | 86 | Apr (past peak) |
| 39 | Ring-billed Gull | Larus delawarensis | Gulls, Terns, and Skimmers | 83 | Aug (past peak) |
| 40 | Tufted Titmouse | Baeolophus bicolor | Tits, Chickadees, and Titmice | 83 | Apr (past peak) |
| 41 | Sandhill Crane | Antigone canadensis | Cranes | 82 | Feb (past peak) |
| 42 | Red-eyed Vireo | Vireo olivaceus | Vireos, Shrike-Babblers, and Erpornis | 82 | May (past peak) |
| 43 | Eastern Phoebe | Sayornis phoebe | Tyrant Flycatchers | 80 | May (past peak) |
| 44 | Nashville Warbler | Leiothlypis ruficapilla | New World Warblers | 77 | May (past peak) |
| 45 | Eastern Bluebird | Sialia sialis | Thrushes | 76 | Apr (past peak) |
| 46 | Chestnut-sided Warbler | Setophaga pensylvanica | New World Warblers | 76 | May (past peak) |
| 47 | Blackpoll Warbler | Setophaga striata | New World Warblers | 74 | May (past peak) |
| 48 | Mute Swan | Cygnus olor | Ducks, Geese, and Swans | 70 | Apr (past peak) |
| 49 | Carolina Chickadee | Poecile carolinensis | Tits, Chickadees, and Titmice | 70 | Apr (past peak) |
| 50 | Blackburnian Warbler | Setophaga fusca | New World Warblers | 69 | May (past peak) |