Confused pairs
Incorrect answers between two species (undirected). With a country selected, only mix-ups from games in that country are counted, and only pairs where both species are on that country's checklist are shown.
| Species A (lower id) | Species B (higher id) | Total wrong | A was target → picked B | B was target → picked A |
|---|---|---|---|---|
| Western Screech-Owl Megascops kennicottii | Northern Saw-whet Owl Aegolius acadicus | 5 | 2 | 3 |
| Western Screech-Owl Megascops kennicottii | Barred Owl Strix varia | 5 | 1 | 4 |
| Flammulated Owl Psiloscops flammeolus | Northern Saw-whet Owl Aegolius acadicus | 5 | 3 | 2 |
| Western Screech-Owl Megascops kennicottii | Short-eared Owl Asio flammeus | 4 | 2 | 2 |
| Purple Martin Progne subis | Barn Swallow Hirundo rustica | 3 | 3 | 0 |
| Black-footed Albatross Phoebastria nigripes | Sooty Shearwater Ardenna grisea | 3 | 3 | 0 |
| Northern Hawk Owl Surnia ulula | Northern Saw-whet Owl Aegolius acadicus | 3 | 0 | 3 |
| Hawaiian Petrel Pterodroma sandwichensis | Great Shearwater Ardenna gravis | 3 | 2 | 1 |
| Wilson's Storm-Petrel Oceanites oceanicus | Hawaiian Petrel Pterodroma sandwichensis | 2 | 2 | 0 |
| Northern Harrier Circus hudsonius | Rough-legged Buzzard Buteo lagopus | 2 | 0 | 2 |
| Black-chinned Hummingbird Archilochus alexandri | Broad-billed Hummingbird Cynanthus latirostris | 2 | 1 | 1 |
| Flammulated Owl Psiloscops flammeolus | Northern Hawk Owl Surnia ulula | 2 | 2 | 0 |
| Western Meadowlark Sturnella neglecta | Yellow-rumped Warbler Setophaga coronata | 2 | 1 | 1 |
| Hawaiian Petrel Pterodroma sandwichensis | Short-tailed Shearwater Ardenna tenuirostris | 2 | 0 | 2 |
| Lapland Bunting Calcarius lapponicus | Western Meadowlark Sturnella neglecta | 2 | 2 | 0 |
| Tree Swallow Tachycineta bicolor | Western Meadowlark Sturnella neglecta | 2 | 0 | 2 |
| Barn Swallow Hirundo rustica | Cliff Swallow Petrochelidon pyrrhonota | 2 | 1 | 1 |
| Sharp-shinned Hawk Accipiter striatus | Swainson's Hawk Buteo swainsoni | 2 | 1 | 1 |
| Black-footed Albatross Phoebastria nigripes | Wedge-tailed Shearwater Ardenna pacifica | 2 | 0 | 2 |
| Western Screech-Owl Megascops kennicottii | Northern Hawk Owl Surnia ulula | 2 | 2 | 0 |
| Garganey Spatula querquedula | Blue-winged Teal Spatula discors | 2 | 0 | 2 |
| Cooper's Hawk Astur cooperii | Swainson's Hawk Buteo swainsoni | 2 | 0 | 2 |
| Slavonian Grebe Podiceps auritus | Brewer's Blackbird Euphagus cyanocephalus | 1 | 1 | 0 |
| Black-necked Grebe Podiceps nigricollis | Temminck's Stint Calidris temminckii | 1 | 0 | 1 |
| Western Grebe Aechmophorus occidentalis | Red-throated Diver Gavia stellata | 1 | 0 | 1 |
| Black-billed Cuckoo Coccyzus erythropthalmus | Orchard Oriole Icterus spurius | 1 | 1 | 0 |
| Lesser Nighthawk Chordeiles acutipennis | Mountain Plover Anarhynchus montanus | 1 | 0 | 1 |
| Common Poorwill Phalaenoptilus nuttallii | Buff-breasted Sandpiper Calidris subruficollis | 1 | 0 | 1 |
| Vaux's Swift Chaetura vauxi | Broad-tailed Hummingbird Selasphorus platycercus | 1 | 0 | 1 |
| White-throated Swift Aeronautes saxatalis | Black-chinned Hummingbird Archilochus alexandri | 1 | 0 | 1 |
| White-throated Swift Aeronautes saxatalis | Anna's Hummingbird Calypte anna | 1 | 0 | 1 |
| Ruby-throated Hummingbird Archilochus colubris | Allen's Hummingbird Selasphorus sasin | 1 | 0 | 1 |
| Ruby-throated Hummingbird Archilochus colubris | Broad-billed Hummingbird Cynanthus latirostris | 1 | 1 | 0 |
| Ruby-throated Hummingbird Archilochus colubris | Cooper's Hawk Astur cooperii | 1 | 1 | 0 |
| Anna's Hummingbird Calypte anna | Allen's Hummingbird Selasphorus sasin | 1 | 1 | 0 |
| Calliope Hummingbird Selasphorus calliope | Rufous Hummingbird Selasphorus rufus | 1 | 0 | 1 |
| Sora Porzana carolina | Eastern Phoebe Sayornis phoebe | 1 | 1 | 0 |
| American Avocet Recurvirostra americana | Mountain Plover Anarhynchus montanus | 1 | 0 | 1 |
| American Avocet Recurvirostra americana | Buff-breasted Sandpiper Calidris subruficollis | 1 | 1 | 0 |
| American Avocet Recurvirostra americana | Great Northern Diver Gavia immer | 1 | 1 | 0 |
| Grey Plover Pluvialis squatarola | Siberian Sand Plover Anarhynchus mongolus | 1 | 1 | 0 |
| Grey Plover Pluvialis squatarola | Long-tailed Skua Stercorarius longicaudus | 1 | 0 | 1 |
| Eurasian Dotterel Eudromias morinellus | Buff-breasted Sandpiper Calidris subruficollis | 1 | 1 | 0 |
| Killdeer Charadrius vociferus | Siberian Sand Plover Anarhynchus mongolus | 1 | 1 | 0 |
| Killdeer Charadrius vociferus | Wilson's Plover Anarhynchus wilsonia | 1 | 0 | 1 |
| Semipalmated Plover Charadrius semipalmatus | Siberian Sand Plover Anarhynchus mongolus | 1 | 1 | 0 |
| Semipalmated Plover Charadrius semipalmatus | Red Knot Calidris canutus | 1 | 1 | 0 |
| Hudsonian Godwit Limosa haemastica | Ruby-crowned Kinglet Corthylio calendula | 1 | 0 | 1 |
| Solitary Sandpiper Tringa solitaria | Snowy Egret Egretta thula | 1 | 0 | 1 |
| Wandering Tattler Tringa incana | Western Cattle-Egret Ardea ibis | 1 | 1 | 0 |
| Red Knot Calidris canutus | Snowy Egret Egretta thula | 1 | 1 | 0 |
| Red Knot Calidris canutus | Pine Siskin Spinus pinus | 1 | 1 | 0 |
| White-rumped Sandpiper Calidris fuscicollis | Short-tailed Shearwater Ardenna tenuirostris | 1 | 1 | 0 |
| Semipalmated Sandpiper Calidris pusilla | Arctic Skua Stercorarius parasiticus | 1 | 0 | 1 |
| Long-tailed Skua Stercorarius longicaudus | Thick-billed Longspur Rhynchophanes mccownii | 1 | 0 | 1 |
| Long-tailed Skua Stercorarius longicaudus | Yellow-throated Warbler Setophaga dominica | 1 | 0 | 1 |
| Arctic Skua Stercorarius parasiticus | Double-crested Cormorant Nannopterum auritum | 1 | 1 | 0 |
| Pomarine Skua Stercorarius pomarinus | Long-tailed Mockingbird Mimus longicaudatus | 1 | 0 | 1 |
| Parakeet Auklet Aethia psittacula | Kittlitz's Murrelet Brachyramphus brevirostris | 1 | 0 | 1 |
| Black-legged Kittiwake Rissa tridactyla | Glaucous-winged Gull Larus glaucescens | 1 | 1 | 0 |
| Red-legged Kittiwake Rissa brevirostris | Laughing Gull Leucophaeus atricilla | 1 | 1 | 0 |
| Red-legged Kittiwake Rissa brevirostris | Short-billed Gull Larus brachyrhynchus | 1 | 1 | 0 |
| Red-legged Kittiwake Rissa brevirostris | Bobolink Dolichonyx oryzivorus | 1 | 0 | 1 |
| Forster's Tern Sterna forsteri | Great Blue Heron Ardea herodias | 1 | 0 | 1 |
| Black-footed Albatross Phoebastria nigripes | Flesh-footed Shearwater Ardenna carneipes | 1 | 0 | 1 |
| Black-footed Albatross Phoebastria nigripes | Great Shearwater Ardenna gravis | 1 | 0 | 1 |
| Short-tailed Albatross Phoebastria albatrus | Fork-tailed Storm-Petrel Hydrobates furcatus | 1 | 0 | 1 |
| Short-tailed Albatross Phoebastria albatrus | Northern Fulmar Fulmarus glacialis | 1 | 1 | 0 |
| Short-tailed Albatross Phoebastria albatrus | Flesh-footed Shearwater Ardenna carneipes | 1 | 0 | 1 |
| Short-tailed Albatross Phoebastria albatrus | Wedge-tailed Shearwater Ardenna pacifica | 1 | 1 | 0 |
| Wilson's Storm-Petrel Oceanites oceanicus | Northern Fulmar Fulmarus glacialis | 1 | 0 | 1 |
| Fork-tailed Storm-Petrel Hydrobates furcatus | Hawaiian Petrel Pterodroma sandwichensis | 1 | 1 | 0 |
| Fork-tailed Storm-Petrel Hydrobates furcatus | Wedge-tailed Shearwater Ardenna pacifica | 1 | 0 | 1 |
| Fork-tailed Storm-Petrel Hydrobates furcatus | Short-tailed Shearwater Ardenna tenuirostris | 1 | 1 | 0 |
| Northern Fulmar Fulmarus glacialis | Great Shearwater Ardenna gravis | 1 | 1 | 0 |
| Northern Fulmar Fulmarus glacialis | Wedge-tailed Shearwater Ardenna pacifica | 1 | 1 | 0 |
| Hawaiian Petrel Pterodroma sandwichensis | Flesh-footed Shearwater Ardenna carneipes | 1 | 1 | 0 |
| Glossy Ibis Plegadis falcinellus | White-faced Ibis Plegadis chihi | 1 | 0 | 1 |
| Golden Eagle Aquila chrysaetos | Red-shouldered Hawk Buteo lineatus | 1 | 0 | 1 |
| Northern Harrier Circus hudsonius | Sharp-shinned Hawk Accipiter striatus | 1 | 1 | 0 |
| Northern Harrier Circus hudsonius | Red-tailed Hawk Buteo jamaicensis | 1 | 1 | 0 |
| Sharp-shinned Hawk Accipiter striatus | Harris's Hawk Parabuteo unicinctus | 1 | 0 | 1 |
| Sharp-shinned Hawk Accipiter striatus | Red-shouldered Hawk Buteo lineatus | 1 | 0 | 1 |
| Sharp-shinned Hawk Accipiter striatus | Broad-winged Hawk Buteo platypterus | 1 | 0 | 1 |
| Sharp-shinned Hawk Accipiter striatus | Red-tailed Hawk Buteo jamaicensis | 1 | 1 | 0 |
| Sharp-shinned Hawk Accipiter striatus | Rough-legged Buzzard Buteo lagopus | 1 | 0 | 1 |
| Cooper's Hawk Astur cooperii | Broad-winged Hawk Buteo platypterus | 1 | 0 | 1 |
| Cooper's Hawk Astur cooperii | Red-tailed Hawk Buteo jamaicensis | 1 | 0 | 1 |
| Harris's Hawk Parabuteo unicinctus | Red-tailed Hawk Buteo jamaicensis | 1 | 0 | 1 |
| Red-tailed Hawk Buteo jamaicensis | Great Horned Owl Bubo virginianus | 1 | 0 | 1 |
| Flammulated Owl Psiloscops flammeolus | Burrowing Owl Athene cunicularia | 1 | 1 | 0 |
| Flammulated Owl Psiloscops flammeolus | Short-eared Owl Asio flammeus | 1 | 0 | 1 |
| Great Horned Owl Bubo virginianus | Short-eared Owl Asio flammeus | 1 | 0 | 1 |
| Burrowing Owl Athene cunicularia | Northern Saw-whet Owl Aegolius acadicus | 1 | 0 | 1 |
| Barred Owl Strix varia | Northern Saw-whet Owl Aegolius acadicus | 1 | 0 | 1 |
| Williamson's Sapsucker Sphyrapicus thyroideus | Acorn Woodpecker Melanerpes formicivorus | 1 | 1 | 0 |
| Red-naped Sapsucker Sphyrapicus nuchalis | Indigo Bunting Passerina cyanea | 1 | 0 | 1 |
| Red-breasted Sapsucker Sphyrapicus ruber | Lewis's Woodpecker Melanerpes lewis | 1 | 0 | 1 |
| Red-breasted Sapsucker Sphyrapicus ruber | Field Sparrow Spizella pusilla | 1 | 1 | 0 |
| Lewis's Woodpecker Melanerpes lewis | Varied Thrush Ixoreus naevius | 1 | 1 | 0 |
| Northern Flicker Colaptes auratus | Grasshopper Sparrow Ammodramus savannarum | 1 | 1 | 0 |
| Common Kestrel Falco tinnunculus | Merlin Falco columbarius | 1 | 0 | 1 |
| American Kestrel Falco sparverius | Thick-billed Longspur Rhynchophanes mccownii | 1 | 0 | 1 |
| Cockatiel Nymphicus hollandicus | Red-rumped Parrot Psephotus haematonotus | 1 | 0 | 1 |
| Olive-sided Flycatcher Contopus cooperi | Buff-bellied Pipit Anthus rubescens | 1 | 0 | 1 |
| Alder Flycatcher Empidonax alnorum | Pygmy Nuthatch Sitta pygmaea | 1 | 0 | 1 |
| Alder Flycatcher Empidonax alnorum | Prairie Warbler Setophaga discolor | 1 | 0 | 1 |
| Willow Flycatcher Empidonax traillii | Least Flycatcher Empidonax minimus | 1 | 0 | 1 |
| Hammond's Flycatcher Empidonax hammondii | Blue-winged Warbler Vermivora cyanoptera | 1 | 0 | 1 |
| Ash-throated Flycatcher Myiarchus cinerascens | Hermit Thrush Catharus guttatus | 1 | 0 | 1 |
| Western Kingbird Tyrannus verticalis | Northern House Wren Troglodytes aedon | 1 | 1 | 0 |
| Hutton's Vireo Vireo huttoni | Swainson's Thrush Catharus ustulatus | 1 | 1 | 0 |
| Cassin's Vireo Vireo cassinii | Palm Warbler Setophaga palmarum | 1 | 1 | 0 |
| American Crow Corvus brachyrhynchos | Common Grackle Quiscalus quiscula | 1 | 1 | 0 |
| Common Raven Corvus corax | American Robin Turdus migratorius | 1 | 0 | 1 |
| Common Raven Corvus corax | Brown-headed Cowbird Molothrus ater | 1 | 0 | 1 |
| Black-capped Chickadee Poecile atricapillus | Blackpoll Warbler Setophaga striata | 1 | 0 | 1 |
| Mountain Chickadee Poecile gambeli | Hermit Warbler Setophaga occidentalis | 1 | 0 | 1 |
| Shore Lark Eremophila alpestris | American Goldfinch Spinus tristis | 1 | 0 | 1 |
| Shore Lark Eremophila alpestris | Western Meadowlark Sturnella neglecta | 1 | 1 | 0 |
| Shore Lark Eremophila alpestris | Red-winged Blackbird Agelaius phoeniceus | 1 | 0 | 1 |
| Sand Martin Riparia riparia | Northern Rough-winged Swallow Stelgidopteryx serripennis | 1 | 1 | 0 |
| Purple Martin Progne subis | Western Meadowlark Sturnella neglecta | 1 | 0 | 1 |
| Purple Martin Progne subis | Brewer's Blackbird Euphagus cyanocephalus | 1 | 0 | 1 |
| Purple Martin Progne subis | Common Grackle Quiscalus quiscula | 1 | 0 | 1 |
| White-breasted Nuthatch Sitta carolinensis | Pygmy Nuthatch Sitta pygmaea | 1 | 0 | 1 |
| Rock Wren Salpinctes obsoletus | Winter Wren Troglodytes hiemalis | 1 | 0 | 1 |
| Bewick's Wren Thryomanes bewickii | Buff-bellied Pipit Anthus rubescens | 1 | 1 | 0 |
| Western Bluebird Sialia mexicana | Mountain Bluebird Sialia currucoides | 1 | 1 | 0 |
| Lapland Bunting Calcarius lapponicus | Yellow-rumped Warbler Setophaga coronata | 1 | 0 | 1 |
| Black-throated Sparrow Amphispiza bilineata | Bobolink Dolichonyx oryzivorus | 1 | 0 | 1 |
| Fox Sparrow Passerella iliaca | Rose-breasted Grosbeak Pheucticus ludovicianus | 1 | 1 | 0 |
| White-crowned Sparrow Zonotrichia leucophrys | Nashville Warbler Leiothlypis ruficapilla | 1 | 1 | 0 |
| Yellow-headed Blackbird Xanthocephalus xanthocephalus | Orchard Oriole Icterus spurius | 1 | 1 | 0 |
| Bobolink Dolichonyx oryzivorus | Tricoloured Blackbird Agelaius tricolor | 1 | 1 | 0 |
| Nashville Warbler Leiothlypis ruficapilla | Kentucky Warbler Geothlypis formosa | 1 | 1 | 0 |
| Townsend's Warbler Setophaga townsendi | Black-throated Green Warbler Setophaga virens | 1 | 0 | 1 |
| Bar-headed Goose Anser indicus | Snow Goose Anser caerulescens | 1 | 0 | 1 |
| Black-throated Green Warbler Setophaga virens | Wilson's Warbler Cardellina pusilla | 1 | 0 | 1 |
| Bar-headed Goose Anser indicus | Semipalmated Plover Charadrius semipalmatus | 1 | 1 | 0 |
| Snow Goose Anser caerulescens | Greater White-fronted Goose Anser albifrons | 1 | 1 | 0 |
| Cackling Goose Branta hutchinsii | Canada Goose Branta canadensis | 1 | 1 | 0 |
| Trumpeter Swan Cygnus buccinator | Bewick's Swan Cygnus columbianus | 1 | 0 | 1 |
| Wood Duck Aix sponsa | Blue-winged Teal Spatula discors | 1 | 0 | 1 |
| Garganey Spatula querquedula | Pine Grosbeak Pinicola enucleator | 1 | 1 | 0 |
| Gadwall Mareca strepera | Western Flycatcher Empidonax difficilis | 1 | 1 | 0 |
| American Wigeon Mareca americana | American Black Duck Anas rubripes | 1 | 1 | 0 |
| Northern Pintail Anas acuta | Common Tern Sterna hirundo | 1 | 0 | 1 |
| Redhead Aythya americana | Ring-necked Duck Aythya collaris | 1 | 1 | 0 |
| Ring-necked Duck Aythya collaris | Greater Scaup Aythya marila | 1 | 0 | 1 |
| Ring-necked Duck Aythya collaris | Lesser Scaup Aythya affinis | 1 | 1 | 0 |
| Greater Scaup Aythya marila | Lesser Scaup Aythya affinis | 1 | 0 | 1 |
| Greater Scaup Aythya marila | Eurasian Dotterel Eudromias morinellus | 1 | 1 | 0 |
| Lesser Scaup Aythya affinis | Pied-billed Grebe Podilymbus podiceps | 1 | 1 | 0 |
| Harlequin Duck Histrionicus histrionicus | Black Scoter Melanitta americana | 1 | 1 | 0 |
| Bufflehead Bucephala albeola | Common Goldeneye Bucephala clangula | 1 | 0 | 1 |
| Bufflehead Bucephala albeola | Hooded Warbler Setophaga citrina | 1 | 1 | 0 |
| Northern Bobwhite Colinus virginianus | Yellow-billed Cuckoo Coccyzus americanus | 1 | 0 | 1 |
| Golden Pheasant Chrysolophus pictus | Bushtit Psaltriparus minimus | 1 | 0 | 1 |
| Slavonian Grebe Podiceps auritus | Western Wood-Pewee Contopus sordidulus | 1 | 0 | 1 |