60 birds were recorded seen in Delaware in December 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 December

Snow Goose

Bald Eagle

Great Blue Heron
Bufflehead

Northern Pintail

Northern Harrier

Northern Cardinal

White-throated Sparrow

Tundra Swan

Sanderling

Song Sparrow

Hooded Merganser
All birds seen in Delaware in December
| # | Species | Scientific name | Family | Obs. | Peak in state |
|---|---|---|---|---|---|
| 1 | Snow Goose | Anser caerulescens | Ducks, Geese, and Swans | 213 | Dec (peak) |
| 2 | Bald Eagle | Haliaeetus leucocephalus | Hawks, Eagles, and Kites | 160 | Apr (past peak) |
| 3 | Great Blue Heron | Ardea herodias | Herons, Egrets, and Bitterns | 143 | May (past peak) |
| 4 | Bufflehead | Bucephala albeola | Ducks, Geese, and Swans | 129 | Jan (past peak) |
| 5 | Northern Pintail | Anas acuta | Ducks, Geese, and Swans | 101 | Feb (past peak) |
| 6 | Northern Harrier | Circus hudsonius | Hawks, Eagles, and Kites | 101 | Dec (peak) |
| 7 | Northern Cardinal | Cardinalis cardinalis | Cardinals and Allies | 91 | Apr (past peak) |
| 8 | White-throated Sparrow | Zonotrichia albicollis | New World Sparrows | 88 | Jan (past peak) |
| 9 | Tundra Swan | Cygnus columbianus | Ducks, Geese, and Swans | 85 | Jan (past peak) |
| 10 | Sanderling | Calidris alba | Sandpipers and Allies | 83 | Aug (past peak) |
| 11 | Song Sparrow | Melospiza melodia | New World Sparrows | 82 | Jan (past peak) |
| 12 | Hooded Merganser | Lophodytes cucullatus | Ducks, Geese, and Swans | 76 | Feb (past peak) |
| 13 | Surf Scoter | Melanitta perspicillata | Ducks, Geese, and Swans | 71 | Jan (past peak) |
| 14 | Northern Shoveler | Spatula clypeata | Ducks, Geese, and Swans | 68 | Mar (past peak) |
| 15 | Red-tailed Hawk | Buteo jamaicensis | Hawks, Eagles, and Kites | 63 | Jan (past peak) |
| 16 | Canada Goose | Branta canadensis | Ducks, Geese, and Swans | 61 | May (past peak) |
| 17 | Dunlin | Calidris alpina | Sandpipers and Allies | 59 | May (past peak) |
| 18 | American Black Duck | Anas rubripes | Ducks, Geese, and Swans | 58 | Jan (past peak) |
| 19 | Downy Woodpecker | Dryobates pubescens | Woodpeckers | 58 | Feb (past peak) |
| 20 | Ring-billed Gull | Larus delawarensis | Gulls, Terns, and Skimmers | 57 | Aug (past peak) |
| 21 | Carolina Chickadee | Poecile carolinensis | Tits, Chickadees, and Titmice | 55 | Apr (past peak) |
| 22 | House Finch | Haemorhous mexicanus | Finches, Euphonias, and Allies | 54 | May (past peak) |
| 23 | Mallard | Anas platyrhynchos | Ducks, Geese, and Swans | 53 | May (past peak) |
| 24 | Red-shouldered Hawk | Buteo lineatus | Hawks, Eagles, and Kites | 52 | Jan (past peak) |
| 25 | Green-winged Teal | Anas crecca | Ducks, Geese, and Swans | 51 | Mar (past peak) |
| 26 | Northern Mockingbird | Mimus polyglottos | Mockingbirds and Thrashers | 48 | Apr (past peak) |
| 27 | Dark-eyed Junco | Junco hyemalis | New World Sparrows | 47 | Jan (past peak) |
| 28 | Cooper's Hawk | Astur cooperii | Hawks, Eagles, and Kites | 47 | Oct (past peak) |
| 29 | Carolina Wren | Thryothorus ludovicianus | Wrens | 44 | May (past peak) |
| 30 | Savannah Sparrow | Passerculus sandwichensis | New World Sparrows | 44 | Oct (past peak) |
| 31 | Yellow-rumped Warbler | Setophaga coronata | New World Warblers | 43 | Oct (past peak) |
| 32 | Turkey Vulture | Cathartes aura | New World Vultures | 42 | Apr (past peak) |
| 33 | Tufted Titmouse | Baeolophus bicolor | Tits, Chickadees, and Titmice | 42 | Jan (past peak) |
| 34 | Red-bellied Woodpecker | Melanerpes carolinus | Woodpeckers | 42 | Mar (past peak) |
| 35 | Ruddy Duck | Oxyura jamaicensis | Ducks, Geese, and Swans | 42 | Mar (past peak) |
| 36 | Belted Kingfisher | Megaceryle alcyon | Kingfishers | 41 | Jan (past peak) |
| 37 | Boat-tailed Grackle | Quiscalus major | New World Blackbirds and Orioles | 41 | Feb (past peak) |
| 38 | Eastern Bluebird | Sialia sialis | Thrushes | 39 | Mar (past peak) |
| 39 | Greater Yellowlegs | Tringa melanoleuca | Sandpipers and Allies | 38 | Apr (past peak) |
| 40 | Great Black-backed Gull | Larus marinus | Gulls, Terns, and Skimmers | 38 | Aug (past peak) |
| 41 | House Sparrow | Passer domesticus | Old World Sparrows | 36 | May (past peak) |
| 42 | Black Vulture | Coragyps atratus | New World Vultures | 35 | Apr (past peak) |
| 43 | American Robin | Turdus migratorius | Thrushes | 35 | Apr (past peak) |
| 44 | Ruddy Turnstone | Arenaria interpres | Sandpipers and Allies | 33 | May (past peak) |
| 45 | American Goldfinch | Spinus tristis | Finches, Euphonias, and Allies | 33 | Apr (past peak) |
| 46 | American Coot | Fulica americana | Rails, Gallinules, and Coots | 32 | Mar (past peak) |
| 47 | Short-eared Owl | Asio flammeus | Typical Owls | 32 | Dec (peak) |
| 48 | Lesser Black-backed Gull | Larus fuscus | Gulls, Terns, and Skimmers | 31 | Oct (past peak) |
| 49 | Red-throated Loon | Gavia stellata | Loons | 31 | Jan (past peak) |
| 50 | Bonaparte's Gull | Chroicocephalus philadelphia | Gulls, Terns, and Skimmers | 31 | Jan (past peak) |