60 birds were recorded seen in Maine in September in our iNaturalist sample; 3 of the top 50 are at their peak this month. The list is ranked by number of research-grade observations.
Top birds in September

American Herring Gull

Double-crested Cormorant

Great Blue Heron

Wild Turkey

Bald Eagle

Common Eider

Semipalmated Plover
Common Loon

Mallard

Ring-billed Gull

Black-capped Chickadee

Great Black-backed Gull
All birds seen in Maine in September
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | American Herring Gull | Larus smithsonianus | Gulls, Terns, and Skimmers | 609 | Aug (past peak) |
| 2 | Double-crested Cormorant | Nannopterum auritum | Cormorants and Shags | 430 | Aug (past peak) |
| 3 | Great Blue Heron | Ardea herodias | Herons, Egrets, and Bitterns | 366 | Aug (past peak) |
| 4 | Wild Turkey | Meleagris gallopavo | Pheasants, Grouse, and Allies | 328 | Aug (past peak) |
| 5 | Bald Eagle | Haliaeetus leucocephalus | Hawks, Eagles, and Kites | 322 | Aug (past peak) |
| 6 | Common Eider | Somateria mollissima | Ducks, Geese, and Swans | 302 | Jun (past peak) |
| 7 | Semipalmated Plover | Charadrius semipalmatus | Plovers and Lapwings | 291 | Aug (past peak) |
| 8 | Common Loon | Gavia immer | Loons | 234 | Jul (past peak) |
| 9 | Mallard | Anas platyrhynchos | Ducks, Geese, and Swans | 234 | Jul (past peak) |
| 10 | Ring-billed Gull | Larus delawarensis | Gulls, Terns, and Skimmers | 212 | Aug (past peak) |
| 11 | Black-capped Chickadee | Poecile atricapillus | Tits, Chickadees, and Titmice | 201 | Oct (rising) |
| 12 | Great Black-backed Gull | Larus marinus | Gulls, Terns, and Skimmers | 175 | Aug (past peak) |
| 13 | Semipalmated Sandpiper | Calidris pusilla | Sandpipers and Allies | 160 | Aug (past peak) |
| 14 | Song Sparrow | Melospiza melodia | New World Sparrows | 157 | Jun (past peak) |
| 15 | Eastern Phoebe | Sayornis phoebe | Tyrant Flycatchers | 152 | Jul (past peak) |
| 16 | Common Yellowthroat | Geothlypis trichas | New World Warblers | 136 | May (past peak) |
| 17 | Osprey | Pandion haliaetus | Ospreys | 133 | Aug (past peak) |
| 18 | Cedar Waxwing | Bombycilla cedrorum | Waxwings | 130 | Jun (past peak) |
| 19 | Yellow-rumped Warbler | Setophaga coronata | New World Warblers | 129 | May (past peak) |
| 20 | Black Guillemot | Cepphus grylle | Auks, Murres, and Puffins | 124 | Jul (past peak) |
| 21 | Great Egret | Ardea alba | Herons, Egrets, and Bitterns | 124 | Aug (past peak) |
| 22 | Sanderling | Calidris alba | Sandpipers and Allies | 119 | Sep (peak) |
| 23 | Greater Yellowlegs | Tringa melanoleuca | Sandpipers and Allies | 118 | Aug (past peak) |
| 24 | American Crow | Corvus brachyrhynchos | Crows, Jays, and Magpies | 112 | Aug (past peak) |
| 25 | Blue Jay | Cyanocitta cristata | Crows, Jays, and Magpies | 111 | Jul (past peak) |
| 26 | Belted Kingfisher | Megaceryle alcyon | Kingfishers | 110 | Sep (peak) |
| 27 | Canada Goose | Branta canadensis | Ducks, Geese, and Swans | 109 | May (past peak) |
| 28 | Gray Catbird | Dumetella carolinensis | Mockingbirds and Thrashers | 109 | May (past peak) |
| 29 | Ruby-throated Hummingbird | Archilochus colubris | Hummingbirds | 106 | Aug (past peak) |
| 30 | American Goldfinch | Spinus tristis | Finches, Euphonias, and Allies | 105 | Aug (past peak) |
| 31 | Red-eyed Vireo | Vireo olivaceus | Vireos, Shrike-Babblers, and Erpornis | 105 | Jul (past peak) |
| 32 | White-throated Sparrow | Zonotrichia albicollis | New World Sparrows | 103 | Oct (rising) |
| 33 | Downy Woodpecker | Dryobates pubescens | Woodpeckers | 103 | Jul (past peak) |
| 34 | Lesser Yellowlegs | Tringa flavipes | Sandpipers and Allies | 101 | Sep (peak) |
| 35 | Pileated Woodpecker | Dryocopus pileatus | Woodpeckers | 99 | May (past peak) |
| 36 | Red-breasted Nuthatch | Sitta canadensis | Nuthatches | 98 | Aug (past peak) |
| 37 | Black-throated Green Warbler | Setophaga virens | New World Warblers | 96 | May (past peak) |
| 38 | Mourning Dove | Zenaida macroura | Pigeons and Doves | 94 | May (past peak) |
| 39 | Hairy Woodpecker | Leuconotopicus villosus | Woodpeckers | 94 | May (past peak) |
| 40 | Least Sandpiper | Calidris minutilla | Sandpipers and Allies | 93 | Aug (past peak) |
| 41 | Savannah Sparrow | Passerculus sandwichensis | New World Sparrows | 92 | May (past peak) |
| 42 | Northern Flicker | Colaptes auratus | Woodpeckers | 92 | Apr (past peak) |
| 43 | Broad-winged Hawk | Buteo platypterus | Hawks, Eagles, and Kites | 91 | Aug (past peak) |
| 44 | White-breasted Nuthatch | Sitta carolinensis | Nuthatches | 81 | Mar (past peak) |
| 45 | Chipping Sparrow | Spizella passerina | New World Sparrows | 77 | May (past peak) |
| 46 | House Sparrow | Passer domesticus | Old World Sparrows | 77 | Jun (past peak) |
| 47 | Laughing Gull | Leucophaeus atricilla | Gulls, Terns, and Skimmers | 75 | Aug (past peak) |
| 48 | Black-and-white Warbler | Mniotilta varia | New World Warblers | 71 | May (past peak) |
| 49 | Barred Owl | Strix varia | Typical Owls | 68 | Jul (past peak) |
| 50 | Spotted Sandpiper | Actitis macularius | Sandpipers and Allies | 68 | Aug (past peak) |