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 |
|---|---|---|---|---|
| King Eider Somateria spectabilis | Common Eider Somateria mollissima | 2 | 2 | 0 |
| Eurasian Woodcock Scolopax rusticola | Common Snipe Gallinago gallinago | 2 | 2 | 0 |
| Common Kestrel Falco tinnunculus | American Kestrel Falco sparverius | 2 | 0 | 2 |
| Iberian Grey Shrike Lanius meridionalis | Woodchat Shrike Lanius senator | 2 | 2 | 0 |
| Western Orphean Warbler Curruca hortensis | Sardinian Warbler Curruca melanocephala | 2 | 2 | 0 |
| Western Subalpine Warbler Curruca iberiae | Dartford Warbler Curruca undata | 2 | 2 | 0 |
| Grey-cheeked Thrush Catharus minimus | Swainson's Thrush Catharus ustulatus | 2 | 0 | 2 |
| Fieldfare Turdus pilaris | Dusky Thrush Turdus eunomus | 2 | 1 | 1 |
| Atlantic Canary Serinus canaria | Eurasian Siskin Spinus spinus | 2 | 1 | 1 |
| Snow Goose Anser caerulescens | Greylag Goose Anser anser | 1 | 1 | 0 |
| Greylag Goose Anser anser | Canada Goose Branta canadensis | 1 | 1 | 0 |
| Greylag Goose Anser anser | Greater White-fronted Goose Anser albifrons | 1 | 0 | 1 |
| Taiga Bean Goose Anser fabalis | Tundra Bean Goose Anser serrirostris | 1 | 1 | 0 |
| Eurasian Wigeon Mareca penelope | American Wigeon Mareca americana | 1 | 0 | 1 |
| Common Pochard Aythya ferina | Ferruginous Duck Aythya nyroca | 1 | 0 | 1 |
| Common Eider Somateria mollissima | Surf Scoter Melanitta perspicillata | 1 | 0 | 1 |
| Common Eider Somateria mollissima | Velvet Scoter Melanitta fusca | 1 | 0 | 1 |
| Long-tailed Duck Clangula hyemalis | Common Goldeneye Bucephala clangula | 1 | 1 | 0 |
| Bufflehead Bucephala albeola | Smew Mergellus albellus | 1 | 0 | 1 |
| Ruddy Duck Oxyura jamaicensis | White-headed Duck Oxyura leucocephala | 1 | 1 | 0 |
| Stock Dove Columba oenas | European Turtle Dove Streptopelia turtur | 1 | 1 | 0 |
| Rock Dove Columba livia | Trocaz Pigeon Columba trocaz | 1 | 0 | 1 |
| Collared Dove Streptopelia decaocto | Black-bellied Sandgrouse Pterocles orientalis | 1 | 1 | 0 |
| Black-bellied Sandgrouse Pterocles orientalis | European Golden Plover Pluvialis apricaria | 1 | 1 | 0 |
| Great Spotted Cuckoo Clamator glandarius | Yellow-billed Cuckoo Coccyzus americanus | 1 | 0 | 1 |
| Yellow-billed Cuckoo Coccyzus americanus | Common Cuckoo Cuculus canorus | 1 | 1 | 0 |
| Common Nighthawk Chordeiles minor | Eurasian Nightjar Caprimulgus europaeus | 1 | 1 | 0 |
| Common Nighthawk Chordeiles minor | Red-necked Nightjar Caprimulgus ruficollis | 1 | 0 | 1 |
| Eurasian Coot Fulica atra | American Coot Fulica americana | 1 | 0 | 1 |
| American Coot Fulica americana | Allen's Gallinule Porphyrio alleni | 1 | 1 | 0 |
| Common Moorhen Gallinula chloropus | Western Swamphen Porphyrio porphyrio | 1 | 0 | 1 |
| European Golden Plover Pluvialis apricaria | American Golden Plover Pluvialis dominica | 1 | 0 | 1 |
| Common Ringed Plover Charadrius hiaticula | Little Ringed Plover Thinornis dubius | 1 | 0 | 1 |
| Kentish Plover Anarhynchus alexandrinus | Upland Sandpiper Bartramia longicauda | 1 | 0 | 1 |
| Black-tailed Godwit Limosa limosa | Short-billed Dowitcher Limnodromus griseus | 1 | 0 | 1 |
| Red-necked Phalarope Phalaropus lobatus | Terek Sandpiper Xenus cinereus | 1 | 0 | 1 |
| Wood Sandpiper Tringa glareola | Lesser Yellowlegs Tringa flavipes | 1 | 1 | 0 |
| Red Knot Calidris canutus | Ruff Calidris pugnax | 1 | 0 | 1 |
| Common Sandpiper Actitis hypoleucos | Curlew Sandpiper Calidris ferruginea | 1 | 0 | 1 |
| Red-necked Stint Calidris ruficollis | Little Stint Calidris minuta | 1 | 1 | 0 |
| Little Stint Calidris minuta | Least Sandpiper Calidris minutilla | 1 | 0 | 1 |
| Pectoral Sandpiper Calidris melanotos | Western Sandpiper Calidris mauri | 1 | 0 | 1 |
| Collared Pratincole Glareola pratincola | Caspian Tern Hydroprogne caspia | 1 | 1 | 0 |
| Long-tailed Skua Stercorarius longicaudus | Arctic Skua Stercorarius parasiticus | 1 | 1 | 0 |
| Long-tailed Skua Stercorarius longicaudus | Pomarine Skua Stercorarius pomarinus | 1 | 0 | 1 |
| Pomarine Skua Stercorarius pomarinus | South Polar Skua Stercorarius maccormicki | 1 | 0 | 1 |
| Sabine's Gull Xema sabini | Bonaparte's Gull Chroicocephalus philadelphia | 1 | 1 | 0 |
| Slender-billed Gull Chroicocephalus genei | Bonaparte's Gull Chroicocephalus philadelphia | 1 | 0 | 1 |
| Herring Gull Larus argentatus | Great Black-backed Gull Larus marinus | 1 | 1 | 0 |
| Lesser Black-backed Gull Larus fuscus | Iceland Gull Larus glaucoides | 1 | 1 | 0 |
| Bridled Tern Onychoprion anaethetus | Gull-billed Tern Gelochelidon nilotica | 1 | 1 | 0 |
| Elegant Tern Thalasseus elegans | Lesser Crested Tern Thalasseus bengalensis | 1 | 1 | 0 |
| Lesser Crested Tern Thalasseus bengalensis | White-tailed Tropicbird Phaethon lepturus | 1 | 1 | 0 |
| Red-throated Diver Gavia stellata | Great Northern Diver Gavia immer | 1 | 0 | 1 |
| Wilson's Storm-Petrel Oceanites oceanicus | Black-bellied Storm-Petrel Fregetta tropica | 1 | 1 | 0 |
| European Storm-Petrel Hydrobates pelagicus | Leach's Storm-Petrel Hydrobates leucorhous | 1 | 1 | 0 |
| European Storm-Petrel Hydrobates pelagicus | Band-rumped Storm-Petrel Hydrobates castro | 1 | 0 | 1 |
| Band-rumped Storm-Petrel Hydrobates castro | Monteiro's Storm-Petrel Hydrobates monteiroi | 1 | 1 | 0 |
| Bulwer's Petrel Bulweria bulwerii | Cape Verde Shearwater Calonectris edwardsii | 1 | 0 | 1 |
| Manx Shearwater Puffinus puffinus | Yelkouan Shearwater Puffinus yelkouan | 1 | 1 | 0 |
| Sooty Shearwater Ardenna grisea | Balearic Shearwater Puffinus mauretanicus | 1 | 0 | 1 |
| European Shag Gulosus aristotelis | Double-crested Cormorant Nannopterum auritum | 1 | 0 | 1 |
| Baillon's Crake Zapornia pusilla | Eurasian Bittern Botaurus stellaris | 1 | 0 | 1 |
| Snowy Egret Egretta thula | Little Egret Egretta garzetta | 1 | 1 | 0 |
| Snowy Egret Egretta thula | Western Reef-Heron Egretta gularis | 1 | 0 | 1 |
| Green Heron Butorides virescens | Squacco Heron Ardeola ralloides | 1 | 1 | 0 |
| African Sacred Ibis Threskiornis aethiopicus | Eurasian Spoonbill Platalea leucorodia | 1 | 0 | 1 |
| European Honey-buzzard Pernis apivorus | Eurasian Goshawk Astur gentilis | 1 | 1 | 0 |
| Steppe Eagle Aquila nipalensis | Spanish Eagle Aquila adalberti | 1 | 1 | 0 |
| Spanish Eagle Aquila adalberti | Western Marsh Harrier Circus aeruginosus | 1 | 0 | 1 |
| Common Buzzard Buteo buteo | Long-legged Buzzard Buteo rufinus | 1 | 0 | 1 |
| American Barn Owl Tyto furcata | Snowy Owl Bubo scandiacus | 1 | 1 | 0 |
| Long-legged Buzzard Buteo rufinus | Eurasian Scops Owl Otus scops | 1 | 0 | 1 |
| Eurasian Scops Owl Otus scops | Tawny Owl Strix aluco | 1 | 1 | 0 |
| Lesser Kestrel Falco naumanni | Western Subalpine Warbler Curruca iberiae | 1 | 1 | 0 |
| Turkestan Shrike Lanius phoenicuroides | Isabelline Wheatear Oenanthe isabellina | 1 | 1 | 0 |
| Iberian Grey Shrike Lanius meridionalis | Common Chaffinch Fringilla coelebs | 1 | 1 | 0 |
| Lesser Grey Shrike Lanius minor | Woodchat Shrike Lanius senator | 1 | 1 | 0 |
| Coal Tit Periparus ater | Great Tit Parus major | 1 | 1 | 0 |
| Greater Short-toed Lark Calandrella brachydactyla | Calandra Lark Melanocorypha calandra | 1 | 1 | 0 |
| Mediterranean Short-toed Lark Alaudala rufescens | Eurasian Skylark Alauda arvensis | 1 | 1 | 0 |
| Woodlark Lullula arborea | Eurasian Skylark Alauda arvensis | 1 | 1 | 0 |
| Booted Warbler Iduna caligata | Western Olivaceous Warbler Iduna opaca | 1 | 1 | 0 |
| Paddyfield Warbler Acrocephalus agricola | Great Reed Warbler Acrocephalus arundinaceus | 1 | 0 | 1 |
| Savi's Warbler Locustella luscinioides | Western Bonelli's Warbler Phylloscopus bonelli | 1 | 1 | 0 |
| Sand Martin Riparia riparia | Western House Martin Delichon urbicum | 1 | 1 | 0 |
| Western House Martin Delichon urbicum | Cliff Swallow Petrochelidon pyrrhonota | 1 | 0 | 1 |
| Wood Warbler Phylloscopus sibilatrix | Hume's Warbler Phylloscopus humei | 1 | 1 | 0 |
| Western Bonelli's Warbler Phylloscopus bonelli | Yellow-browed Warbler Phylloscopus inornatus | 1 | 1 | 0 |
| Western Bonelli's Warbler Phylloscopus bonelli | Ortolan Bunting Emberiza hortulana | 1 | 1 | 0 |
| Yellow-browed Warbler Phylloscopus inornatus | Pallas's Warbler Phylloscopus proregulus | 1 | 1 | 0 |
| Common Chiffchaff Phylloscopus collybita | Arctic Warbler Phylloscopus borealis | 1 | 0 | 1 |
| Garden Warbler Sylvia borin | Lesser Whitethroat Curruca curruca | 1 | 1 | 0 |
| Western Orphean Warbler Curruca hortensis | Common Whitethroat Curruca communis | 1 | 1 | 0 |
| Western Subalpine Warbler Curruca iberiae | Spectacled Warbler Curruca conspicillata | 1 | 1 | 0 |
| Gull-billed Tern Gelochelidon nilotica | Common Whitethroat Curruca communis | 1 | 0 | 1 |
| Spectacled Warbler Curruca conspicillata | Dartford Warbler Curruca undata | 1 | 0 | 1 |
| Madeira Firecrest Regulus madeirensis | Common Firecrest Regulus ignicapilla | 1 | 0 | 1 |
| Demoiselle Crane Grus virgo | White-throated Dipper Cinclus cinclus | 1 | 0 | 1 |
| Wood Thrush Hylocichla mustelina | Mistle Thrush Turdus viscivorus | 1 | 1 | 0 |
| Bluethroat Luscinia svecica | Red-breasted Flycatcher Ficedula parva | 1 | 0 | 1 |
| Northern Wheatear Oenanthe oenanthe | Western Black-eared Wheatear Oenanthe hispanica | 1 | 1 | 0 |
| Desert Wheatear Oenanthe deserti | Western Black-eared Wheatear Oenanthe hispanica | 1 | 0 | 1 |
| Eurasian Tree Sparrow Passer montanus | Rock Sparrow Petronia petronia | 1 | 0 | 1 |
| Tawny Pipit Anthus campestris | Berthelot's Pipit Anthus berthelotii | 1 | 1 | 0 |
| Blyth's Pipit Anthus godlewskii | Berthelot's Pipit Anthus berthelotii | 1 | 0 | 1 |
| Tawny Pipit Anthus campestris | Meadow Pipit Anthus pratensis | 1 | 0 | 1 |
| Rock Pipit Anthus petrosus | Buff-bellied Pipit Anthus rubescens | 1 | 0 | 1 |
| Azores Chaffinch Fringilla moreletti | Madeira Chaffinch Fringilla maderensis | 1 | 1 | 0 |
| Madeira Chaffinch Fringilla maderensis | Brambling Fringilla montifringilla | 1 | 0 | 1 |
| Brambling Fringilla montifringilla | Common Rosefinch Carpodacus erythrinus | 1 | 0 | 1 |
| Common Rosefinch Carpodacus erythrinus | European Greenfinch Chloris chloris | 1 | 1 | 0 |
| European Serin Serinus serinus | Atlantic Canary Serinus canaria | 1 | 0 | 1 |
| European Serin Serinus serinus | Cirl Bunting Emberiza cirlus | 1 | 0 | 1 |
| Atlantic Canary Serinus canaria | Yellowhammer Emberiza citrinella | 1 | 0 | 1 |
| Corn Bunting Emberiza calandra | Ortolan Bunting Emberiza hortulana | 1 | 0 | 1 |
| Common Reed Bunting Emberiza schoeniclus | Little Bunting Emberiza pusilla | 1 | 0 | 1 |
| Little Bunting Emberiza pusilla | Rustic Bunting Emberiza rustica | 1 | 1 | 0 |
| Lincoln's Sparrow Melospiza lincolnii | Bobolink Dolichonyx oryzivorus | 1 | 1 | 0 |
| Ovenbird Seiurus aurocapilla | Blue-winged Warbler Vermivora cyanoptera | 1 | 1 | 0 |
| Connecticut Warbler Oporornis agilis | Mourning Warbler Geothlypis philadelphia | 1 | 1 | 0 |
| Tennessee Warbler Leiothlypis peregrina | Mourning Warbler Geothlypis philadelphia | 1 | 0 | 1 |
| Rose-breasted Grosbeak Pheucticus ludovicianus | Indigo Bunting Passerina cyanea | 1 | 0 | 1 |