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 |
|---|---|---|---|---|
| Hen Harrier Circus cyaneus | Montagu's Harrier Circus pygargus | 3 | 3 | 0 |
| American Golden Plover Pluvialis dominica | Pacific Golden Plover Pluvialis fulva | 2 | 1 | 1 |
| Grey Phalarope Phalaropus fulicarius | Red-necked Phalarope Phalaropus lobatus | 2 | 2 | 0 |
| Black-throated Diver Gavia arctica | Pacific Diver Gavia pacifica | 2 | 0 | 2 |
| Black Vulture Aegypius monachus | Griffon Vulture Gyps fulvus | 2 | 2 | 0 |
| Western Marsh Harrier Circus aeruginosus | Hen Harrier Circus cyaneus | 2 | 1 | 1 |
| Common Buzzard Buteo buteo | Long-legged Buzzard Buteo rufinus | 2 | 0 | 2 |
| Eleonora's Falcon Falco eleonorae | Peregrine Falcon Falco peregrinus | 2 | 0 | 2 |
| Wood Warbler Phylloscopus sibilatrix | Western Bonelli's Warbler Phylloscopus bonelli | 2 | 0 | 2 |
| Dusky Warbler Phylloscopus fuscatus | Canary Islands Chiffchaff Phylloscopus canariensis | 2 | 2 | 0 |
| Greater White-fronted Goose Anser albifrons | Pink-footed Goose Anser brachyrhynchus | 1 | 1 | 0 |
| Bewick's Swan Cygnus columbianus | Whooper Swan Cygnus cygnus | 1 | 1 | 0 |
| Common Shelduck Tadorna tadorna | Gadwall Mareca strepera | 1 | 0 | 1 |
| Gadwall Mareca strepera | Eurasian Wigeon Mareca penelope | 1 | 1 | 0 |
| Common Scoter Melanitta nigra | Black Scoter Melanitta americana | 1 | 0 | 1 |
| Common Goldeneye Bucephala clangula | Smew Mergellus albellus | 1 | 0 | 1 |
| Smew Mergellus albellus | Goosander Mergus merganser | 1 | 1 | 0 |
| Bolle's Pigeon Columba bollii | Laurel Pigeon Columba junoniae | 1 | 1 | 0 |
| Alpine Swift Tachymarptis melba | Pallid Swift Apus pallidus | 1 | 1 | 0 |
| Common Swift Apus apus | Plain Swift Apus unicolor | 1 | 0 | 1 |
| Pallid Swift Apus pallidus | Dupont's Lark Chersophilus duponti | 1 | 1 | 0 |
| Plain Swift Apus unicolor | Little Swift Apus affinis | 1 | 0 | 1 |
| Black-winged Stilt Himantopus himantopus | Eyebrowed Thrush Turdus obscurus | 1 | 1 | 0 |
| Grey Plover Pluvialis squatarola | Pacific Golden Plover Pluvialis fulva | 1 | 1 | 0 |
| European Golden Plover Pluvialis apricaria | American Golden Plover Pluvialis dominica | 1 | 0 | 1 |
| Eurasian/Green-winged Teal Anas crecca | Killdeer Charadrius vociferus | 1 | 0 | 1 |
| Rock Dove Columba livia | Northern Lapwing Vanellus vanellus | 1 | 0 | 1 |
| Whimbrel Numenius phaeopus | Black-tailed Godwit Limosa limosa | 1 | 1 | 0 |
| Common Snipe Gallinago gallinago | Wilson's Snipe Gallinago delicata | 1 | 0 | 1 |
| Terek Sandpiper Xenus cinereus | Ortolan Bunting Emberiza hortulana | 1 | 1 | 0 |
| Green Sandpiper Tringa ochropus | Wood Sandpiper Tringa glareola | 1 | 1 | 0 |
| Common Sandpiper Actitis hypoleucos | Common Redshank Tringa totanus | 1 | 0 | 1 |
| Lesser Yellowlegs Tringa flavipes | Spotted Redshank Tringa erythropus | 1 | 1 | 0 |
| Ruddy Turnstone Arenaria interpres | Sanderling Calidris alba | 1 | 1 | 0 |
| Dunlin Calidris alpina | Purple Heron Ardea purpurea | 1 | 1 | 0 |
| Little Stint Calidris minuta | Least Sandpiper Calidris minutilla | 1 | 1 | 0 |
| White-rumped Sandpiper Calidris fuscicollis | Western Sandpiper Calidris mauri | 1 | 0 | 1 |
| Black-winged Pratincole Glareola nordmanni | Collared Pratincole Glareola pratincola | 1 | 1 | 0 |
| Long-tailed Skua Stercorarius longicaudus | Pomarine Skua Stercorarius pomarinus | 1 | 1 | 0 |
| Long-tailed Skua Stercorarius longicaudus | Arctic Skua Stercorarius parasiticus | 1 | 0 | 1 |
| Red-breasted Merganser Mergus serrator | Pomarine Skua Stercorarius pomarinus | 1 | 0 | 1 |
| Rock Dove Columba livia | Great Skua Stercorarius skua | 1 | 0 | 1 |
| Arctic Skua Stercorarius parasiticus | Great Skua Stercorarius skua | 1 | 0 | 1 |
| Black Guillemot Cepphus grylle | Little Auk Alle alle | 1 | 1 | 0 |
| Little Gull Hydrocoloeus minutus | Ross's Gull Rhodostethia rosea | 1 | 1 | 0 |
| Little Gull Hydrocoloeus minutus | Black-legged Kittiwake Rissa tridactyla | 1 | 0 | 1 |
| Black-legged Kittiwake Rissa tridactyla | Slender-billed Gull Chroicocephalus genei | 1 | 1 | 0 |
| Slender-billed Gull Chroicocephalus genei | Audouin's Gull Ichthyaetus audouinii | 1 | 1 | 0 |
| Black-headed Gull Chroicocephalus ridibundus | Mediterranean Gull Ichthyaetus melanocephalus | 1 | 0 | 1 |
| Ring-billed Gull Larus delawarensis | Yellow-legged Gull Larus michahellis | 1 | 1 | 0 |
| Kelp Gull Larus dominicanus | Great Black-backed Gull Larus marinus | 1 | 1 | 0 |
| Herring Gull Larus argentatus | Glaucous Gull Larus hyperboreus | 1 | 1 | 0 |
| Sooty Tern Onychoprion fuscatus | Little Tern Sternula albifrons | 1 | 0 | 1 |
| Least Tern Sternula antillarum | Caspian Tern Hydroprogne caspia | 1 | 0 | 1 |
| Common Tern Sterna hirundo | Roseate Tern Sterna dougallii | 1 | 0 | 1 |
| Gull-billed Tern Gelochelidon nilotica | Sandwich Tern Thalasseus sandvicensis | 1 | 0 | 1 |
| Swinhoe's Storm-Petrel Hydrobates monorhis | Bulwer's Petrel Bulweria bulwerii | 1 | 1 | 0 |
| Leach's Storm-Petrel Hydrobates leucorhous | Band-rumped Storm-Petrel Hydrobates castro | 1 | 0 | 1 |
| Northern Fulmar Fulmarus glacialis | Zino's Petrel Pterodroma madeira | 1 | 0 | 1 |
| Zino's Petrel Pterodroma madeira | Fea's Petrel Pterodroma feae | 1 | 0 | 1 |
| Cory's Shearwater Calonectris diomedea | Sooty Shearwater Ardenna grisea | 1 | 1 | 0 |
| Manx Shearwater Puffinus puffinus | Yelkouan Shearwater Puffinus yelkouan | 1 | 1 | 0 |
| Manx Shearwater Puffinus puffinus | Barolo Shearwater Puffinus baroli | 1 | 1 | 0 |
| Sooty Shearwater Ardenna grisea | Yelkouan Shearwater Puffinus yelkouan | 1 | 0 | 1 |
| Northern Gannet Morus bassanus | Red-footed Booby Sula sula | 1 | 0 | 1 |
| Great Cormorant Phalacrocorax carbo | Double-crested Cormorant Nannopterum auritum | 1 | 0 | 1 |
| European Shag Gulosus aristotelis | Double-crested Cormorant Nannopterum auritum | 1 | 0 | 1 |
| European Shag Gulosus aristotelis | Great White Pelican Pelecanus onocrotalus | 1 | 0 | 1 |
| Little Egret Egretta garzetta | Great White Egret Ardea alba | 1 | 0 | 1 |
| Black Vulture Aegypius monachus | Rüppell's Griffon Gyps rueppelli | 1 | 0 | 1 |
| Rüppell's Griffon Gyps rueppelli | Griffon Vulture Gyps fulvus | 1 | 1 | 0 |
| Short-toed Eagle Circaetus gallicus | Lesser Spotted Eagle Clanga pomarina | 1 | 0 | 1 |
| Lesser Spotted Eagle Clanga pomarina | Steppe Eagle Aquila nipalensis | 1 | 1 | 0 |
| Lesser Spotted Eagle Clanga pomarina | Greater Spotted Eagle Clanga clanga | 1 | 0 | 1 |
| Booted Eagle Hieraaetus pennatus | Imperial Eagle Aquila heliaca | 1 | 1 | 0 |
| Booted Eagle Hieraaetus pennatus | Steppe Eagle Aquila nipalensis | 1 | 0 | 1 |
| Spanish Eagle Aquila adalberti | Golden Eagle Aquila chrysaetos | 1 | 1 | 0 |
| Bonelli's Eagle Aquila fasciata | Pallid Harrier Circus macrourus | 1 | 1 | 0 |
| Eurasian Sparrowhawk Accipiter nisus | Eurasian Goshawk Astur gentilis | 1 | 1 | 0 |
| Rough-legged Buzzard Buteo lagopus | Long-legged Buzzard Buteo rufinus | 1 | 1 | 0 |
| American Barn Owl Tyto furcata | Little Owl Athene noctua | 1 | 1 | 0 |
| Pharaoh Eagle Owl Bubo ascalaphus | Eurasian Eagle Owl Bubo bubo | 1 | 1 | 0 |
| Tawny Owl Strix aluco | Maghreb Owl Strix mauritanica | 1 | 0 | 1 |
| Long-eared Owl Asio otus | Tengmalm's Owl Aegolius funereus | 1 | 1 | 0 |
| White-backed Woodpecker Dendrocopos leucotos | Levaillant's Woodpecker Picus vaillantii | 1 | 1 | 0 |
| Middle Spotted Woodpecker Dendrocoptes medius | Great Spotted Woodpecker Dendrocopos major | 1 | 0 | 1 |
| White-backed Woodpecker Dendrocopos leucotos | Lesser Spotted Woodpecker Dryobates minor | 1 | 0 | 1 |
| Levaillant's Woodpecker Picus vaillantii | Iberian Green Woodpecker Picus sharpei | 1 | 1 | 0 |
| Plain Swift Apus unicolor | Iberian Green Woodpecker Picus sharpei | 1 | 0 | 1 |
| Red-billed Tropicbird Phaethon aethereus | Common Kestrel Falco tinnunculus | 1 | 0 | 1 |
| Common Kestrel Falco tinnunculus | Merlin Falco columbarius | 1 | 1 | 0 |
| Saker Falcon Falco cherrug | Gyr Falcon Falco rusticolus | 1 | 1 | 0 |
| Common Redshank Tringa totanus | Black-crowned Tchagra Tchagra senegalus | 1 | 0 | 1 |
| Black-crowned Tchagra Tchagra senegalus | Red-backed Shrike Lanius collurio | 1 | 1 | 0 |
| Iberian Grey Shrike Lanius meridionalis | Great Grey Shrike Lanius excubitor | 1 | 1 | 0 |
| Red-billed Chough Pyrrhocorax pyrrhocorax | Alpine Chough Pyrrhocorax graculus | 1 | 0 | 1 |
| Eurasian Jackdaw Coloeus monedula | Carrion Crow Corvus corone | 1 | 1 | 0 |
| Carrion Crow Corvus corone | Common Raven Corvus corax | 1 | 0 | 1 |
| Red-backed Shrike Lanius collurio | Eurasian Penduline Tit Remiz pendulinus | 1 | 0 | 1 |
| Greater Short-toed Lark Calandrella brachydactyla | Calandra Lark Melanocorypha calandra | 1 | 1 | 0 |
| Great Spotted Woodpecker Dendrocopos major | Thekla's Lark Galerida theklae | 1 | 0 | 1 |
| Thekla's Lark Galerida theklae | Crested Lark Galerida cristata | 1 | 0 | 1 |
| Booted Warbler Iduna caligata | Western Olivaceous Warbler Iduna opaca | 1 | 1 | 0 |
| Booted Warbler Iduna caligata | Melodious Warbler Hippolais polyglotta | 1 | 1 | 0 |
| Eastern Olivaceous Warbler Iduna pallida | Icterine Warbler Hippolais icterina | 1 | 1 | 0 |
| Western Olivaceous Warbler Iduna opaca | Aquatic Warbler Acrocephalus paludicola | 1 | 1 | 0 |
| Melodious Warbler Hippolais polyglotta | Great Reed Warbler Acrocephalus arundinaceus | 1 | 1 | 0 |
| Moustached Warbler Acrocephalus melanopogon | Sedge Warbler Acrocephalus schoenobaenus | 1 | 1 | 0 |
| Sedge Warbler Acrocephalus schoenobaenus | Paddyfield Warbler Acrocephalus agricola | 1 | 0 | 1 |
| Common Snipe Gallinago gallinago | Great Reed Warbler Acrocephalus arundinaceus | 1 | 0 | 1 |
| Canary Islands Chiffchaff Phylloscopus canariensis | Iberian Chiffchaff Phylloscopus ibericus | 1 | 1 | 0 |
| Wood Warbler Phylloscopus sibilatrix | Common Chiffchaff Phylloscopus collybita | 1 | 0 | 1 |
| Common Chiffchaff Phylloscopus collybita | Iberian Chiffchaff Phylloscopus ibericus | 1 | 0 | 1 |
| Barred Warbler Curruca nisoria | Western Orphean Warbler Curruca hortensis | 1 | 1 | 0 |
| Tristram's Warbler Curruca deserticola | Western Subalpine Warbler Curruca iberiae | 1 | 1 | 0 |
| Sardinian Warbler Curruca melanocephala | Moltoni's Warbler Curruca subalpina | 1 | 1 | 0 |
| Moltoni's Warbler Curruca subalpina | Western Subalpine Warbler Curruca iberiae | 1 | 1 | 0 |
| Western Subalpine Warbler Curruca iberiae | Eastern Subalpine Warbler Curruca cantillans | 1 | 0 | 1 |
| Common Whitethroat Curruca communis | Spectacled Warbler Curruca conspicillata | 1 | 1 | 0 |
| Spectacled Warbler Curruca conspicillata | Marmora's Warbler Curruca sarda | 1 | 0 | 1 |
| Dartford Warbler Curruca undata | European Goldfinch Carduelis carduelis | 1 | 1 | 0 |
| Eurasian Treecreeper Certhia familiaris | Short-toed Treecreeper Certhia brachydactyla | 1 | 1 | 0 |
| Short-toed Treecreeper Certhia brachydactyla | European Goldfinch Carduelis carduelis | 1 | 1 | 0 |
| Grey Catbird Dumetella carolinensis | Swainson's Thrush Catharus ustulatus | 1 | 0 | 1 |
| European Golden Plover Pluvialis apricaria | Song Thrush Turdus philomelos | 1 | 0 | 1 |
| Eurasian Blackbird Turdus merula | Cirl Bunting Emberiza cirlus | 1 | 1 | 0 |
| Common Kingfisher Alcedo atthis | Red-breasted Flycatcher Ficedula parva | 1 | 0 | 1 |
| Red-breasted Flycatcher Ficedula parva | Collared Flycatcher Ficedula albicollis | 1 | 0 | 1 |
| European Pied Flycatcher Ficedula hypoleuca | Collared Flycatcher Ficedula albicollis | 1 | 0 | 1 |
| Moussier's Redstart Phoenicurus moussieri | Common Rock Thrush Monticola saxatilis | 1 | 1 | 0 |
| Whinchat Saxicola rubetra | European Stonechat Saxicola rubicola | 1 | 1 | 0 |
| Northern Wheatear Oenanthe oenanthe | Isabelline Wheatear Oenanthe isabellina | 1 | 0 | 1 |
| Western Black-eared Wheatear Oenanthe hispanica | Black Wheatear Oenanthe leucura | 1 | 0 | 1 |
| Alpine Accentor Prunella collaris | Dunnock Prunella modularis | 1 | 0 | 1 |
| Dunnock Prunella modularis | European Goldfinch Carduelis carduelis | 1 | 1 | 0 |
| Richard's Pipit Anthus richardi | Berthelot's Pipit Anthus berthelotii | 1 | 1 | 0 |
| Richard's Pipit Anthus richardi | Blyth's Pipit Anthus godlewskii | 1 | 0 | 1 |
| Tawny Pipit Anthus campestris | Berthelot's Pipit Anthus berthelotii | 1 | 0 | 1 |
| Meadow Pipit Anthus pratensis | Tree Pipit Anthus trivialis | 1 | 1 | 0 |
| Water Pipit Anthus spinoletta | Rock Pipit Anthus petrosus | 1 | 0 | 1 |
| Rock Pipit Anthus petrosus | Buff-bellied Pipit Anthus rubescens | 1 | 0 | 1 |
| Canary Islands Chaffinch Fringilla canariensis | African Chaffinch Fringilla spodiogenys | 1 | 1 | 0 |
| Common Chaffinch Fringilla coelebs | African Chaffinch Fringilla spodiogenys | 1 | 0 | 1 |
| Tenerife Blue Chaffinch Fringilla teydea | Gran Canaria Blue Chaffinch Fringilla polatzeki | 1 | 1 | 0 |
| Spanish Sparrow Passer hispaniolensis | Common Linnet Linaria cannabina | 1 | 0 | 1 |
| White-faced Storm-Petrel Pelagodroma marina | Citril Finch Carduelis citrinella | 1 | 0 | 1 |
| Common Nightingale Luscinia megarhynchos | Atlantic Canary Serinus canaria | 1 | 0 | 1 |
| Dartford Warbler Curruca undata | Corn Bunting Emberiza calandra | 1 | 0 | 1 |
| Northern Lapwing Vanellus vanellus | Cirl Bunting Emberiza cirlus | 1 | 0 | 1 |
| Ortolan Bunting Emberiza hortulana | Common Reed Bunting Emberiza schoeniclus | 1 | 1 | 0 |
| Baltimore Oriole Icterus galbula | Rose-breasted Grosbeak Pheucticus ludovicianus | 1 | 1 | 0 |