60 birds were recorded seen in District of Columbia in September in our iNaturalist sample; 9 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top birds in September

House Sparrow

Mallard

Great Egret

European Starling

Northern Mockingbird

Northern Cardinal

Mourning Dove

Great Blue Heron

American Robin
Gray Catbird

Blue Jay

American Goldfinch
All birds seen in District of Columbia in September
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | House Sparrow | Passer domesticus | Old World Sparrows | 365 | Apr (past peak) |
| 2 | Mallard | Anas platyrhynchos | Ducks, Geese, and Swans | 251 | Apr (past peak) |
| 3 | Great Egret | Ardea alba | Herons, Egrets, and Bitterns | 216 | Sep (peak) |
| 4 | European Starling | Sturnus vulgaris | Starlings | 210 | Apr (past peak) |
| 5 | Northern Mockingbird | Mimus polyglottos | Mockingbirds and Thrashers | 185 | Apr (past peak) |
| 6 | Northern Cardinal | Cardinalis cardinalis | Cardinals and Allies | 169 | Apr (past peak) |
| 7 | Mourning Dove | Zenaida macroura | Pigeons and Doves | 166 | Apr (past peak) |
| 8 | Great Blue Heron | Ardea herodias | Herons, Egrets, and Bitterns | 155 | May (past peak) |
| 9 | American Robin | Turdus migratorius | Thrushes | 145 | Apr (past peak) |
| 10 | Gray Catbird | Dumetella carolinensis | Mockingbirds and Thrashers | 103 | Jun (past peak) |
| 11 | Blue Jay | Cyanocitta cristata | Crows, Jays, and Magpies | 92 | Jun (past peak) |
| 12 | American Goldfinch | Spinus tristis | Finches, Euphonias, and Allies | 84 | Aug (past peak) |
| 13 | Common Yellowthroat | Geothlypis trichas | New World Warblers | 69 | Sep (peak) |
| 14 | Eastern Wood-Pewee | Contopus virens | Tyrant Flycatchers | 58 | Sep (peak) |
| 15 | Green Heron | Butorides virescens | Herons, Egrets, and Bitterns | 53 | Jul (past peak) |
| 16 | Red-bellied Woodpecker | Melanerpes carolinus | Woodpeckers | 53 | Mar (past peak) |
| 17 | Northern Flicker | Colaptes auratus | Woodpeckers | 53 | Apr (past peak) |
| 18 | Wood Duck | Aix sponsa | Ducks, Geese, and Swans | 51 | Apr (past peak) |
| 19 | Double-crested Cormorant | Nannopterum auritum | Cormorants and Shags | 51 | Apr (past peak) |
| 20 | Red-tailed Hawk | Buteo jamaicensis | Hawks, Eagles, and Kites | 49 | Jan (past peak) |
| 21 | Ruby-throated Hummingbird | Archilochus colubris | Hummingbirds | 47 | Sep (peak) |
| 22 | Canada Goose | Branta canadensis | Ducks, Geese, and Swans | 47 | May (past peak) |
| 23 | Carolina Wren | Thryothorus ludovicianus | Wrens | 47 | Apr (past peak) |
| 24 | Downy Woodpecker | Dryobates pubescens | Woodpeckers | 47 | Mar (past peak) |
| 25 | American Redstart | Setophaga ruticilla | New World Warblers | 46 | Sep (peak) |
| 26 | Black-and-white Warbler | Mniotilta varia | New World Warblers | 45 | Sep (peak) |
| 27 | Cooper's Hawk | Astur cooperii | Hawks, Eagles, and Kites | 39 | Dec (rising) |
| 28 | Red-shouldered Hawk | Buteo lineatus | Hawks, Eagles, and Kites | 38 | Jan (past peak) |
| 29 | Common Grackle | Quiscalus quiscula | New World Blackbirds and Orioles | 38 | Apr (past peak) |
| 30 | Ring-billed Gull | Larus delawarensis | Gulls, Terns, and Skimmers | 33 | Feb (past peak) |
| 31 | Laughing Gull | Leucophaeus atricilla | Gulls, Terns, and Skimmers | 33 | Sep (peak) |
| 32 | Rose-breasted Grosbeak | Pheucticus ludovicianus | Cardinals and Allies | 29 | Sep (peak) |
| 33 | Cape May Warbler | Setophaga tigrina | New World Warblers | 29 | Sep (peak) |
| 34 | Magnolia Warbler | Setophaga magnolia | New World Warblers | 29 | May (past peak) |
| 35 | Red-eyed Vireo | Vireo olivaceus | Vireos, Shrike-Babblers, and Erpornis | 29 | May (past peak) |
| 36 | Scarlet Tanager | Piranga olivacea | Cardinals and Allies | 28 | May (past peak) |
| 37 | White-breasted Nuthatch | Sitta carolinensis | Nuthatches | 28 | Feb (past peak) |
| 38 | Belted Kingfisher | Megaceryle alcyon | Kingfishers | 25 | Jan (past peak) |
| 39 | Northern Parula | Setophaga americana | New World Warblers | 25 | May (past peak) |
| 40 | Tufted Titmouse | Baeolophus bicolor | Tits, Chickadees, and Titmice | 24 | Mar (past peak) |
| 41 | Pileated Woodpecker | Dryocopus pileatus | Woodpeckers | 24 | Apr (past peak) |
| 42 | Black-throated Blue Warbler | Setophaga caerulescens | New World Warblers | 24 | Oct (rising) |
| 43 | Song Sparrow | Melospiza melodia | New World Sparrows | 23 | Mar (past peak) |
| 44 | Red-winged Blackbird | Agelaius phoeniceus | New World Blackbirds and Orioles | 23 | Apr (past peak) |
| 45 | Eastern Phoebe | Sayornis phoebe | Tyrant Flycatchers | 23 | Apr (past peak) |
| 46 | Carolina Chickadee | Poecile carolinensis | Tits, Chickadees, and Titmice | 23 | Mar (past peak) |
| 47 | Bald Eagle | Haliaeetus leucocephalus | Hawks, Eagles, and Kites | 22 | Mar (past peak) |
| 48 | Osprey | Pandion haliaetus | Ospreys | 21 | Apr (past peak) |
| 49 | Brown Thrasher | Toxostoma rufum | Mockingbirds and Thrashers | 20 | Apr (past peak) |
| 50 | Ovenbird | Seiurus aurocapilla | New World Warblers | 20 | May (past peak) |