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 |
|---|---|---|---|---|
| Common Magpie Pica pica | Black-billed Magpie Pica hudsonia | 2 | 2 | 0 |
| Double-crested Cormorant Nannopterum auritum | Neotropic Cormorant Nannopterum brasilianum | 2 | 0 | 2 |
| Mallard Anas platyrhynchos | American Black Duck Anas rubripes | 1 | 0 | 1 |
| Long-tailed Duck Clangula hyemalis | Western Cattle-Egret Ardea ibis | 1 | 1 | 0 |
| Black-billed Cuckoo Coccyzus erythropthalmus | Eastern Whip-poor-will Antrostomus vociferus | 1 | 0 | 1 |
| Chimney Swift Chaetura pelagica | White-throated Swift Aeronautes saxatalis | 1 | 1 | 0 |
| Sandhill Crane Antigone canadensis | Purple Martin Progne subis | 1 | 0 | 1 |
| Common Ringed Plover Charadrius hiaticula | Semipalmated Plover Charadrius semipalmatus | 1 | 1 | 0 |
| Greater Sand Plover Anarhynchus leschenaultii | Wilson's Plover Anarhynchus wilsonia | 1 | 1 | 0 |
| Short-billed Dowitcher Limnodromus griseus | Long-billed Dowitcher Limnodromus scolopaceus | 1 | 1 | 0 |
| Baird's Sandpiper Calidris bairdii | Pectoral Sandpiper Calidris melanotos | 1 | 0 | 1 |
| Crested Auklet Aethia cristatella | Parakeet Auklet Aethia psittacula | 1 | 0 | 1 |
| Kittlitz's Murrelet Brachyramphus brevirostris | Great Black-backed Gull Larus marinus | 1 | 1 | 0 |
| Swallow-tailed Gull Creagrus furcatus | Red-legged Kittiwake Rissa brevirostris | 1 | 1 | 0 |
| Pelagic Cormorant Urile pelagicus | Neotropic Cormorant Nannopterum brasilianum | 1 | 1 | 0 |
| Grey Flycatcher Empidonax wrightii | Western Flycatcher Empidonax difficilis | 1 | 1 | 0 |
| White-eyed Vireo Vireo griseus | Grey Vireo Vireo vicinior | 1 | 0 | 1 |
| Black-billed Magpie Pica hudsonia | Pied Crow Corvus albus | 1 | 0 | 1 |
| American Crow Corvus brachyrhynchos | Brewer's Blackbird Euphagus cyanocephalus | 1 | 1 | 0 |
| Shore Lark Eremophila alpestris | Brown-headed Cowbird Molothrus ater | 1 | 1 | 0 |
| Tree Swallow Tachycineta bicolor | American Robin Turdus migratorius | 1 | 0 | 1 |
| Purple Martin Progne subis | Brown-headed Cowbird Molothrus ater | 1 | 1 | 0 |
| Barn Swallow Hirundo rustica | Cliff Swallow Petrochelidon pyrrhonota | 1 | 1 | 0 |
| Wood Thrush Hylocichla mustelina | Rufous-backed Robin Turdus rufopalliatus | 1 | 0 | 1 |
| Siberian Rubythroat Calliope calliope | Northern Wheatear Oenanthe oenanthe | 1 | 1 | 0 |
| Common Rosefinch Carpodacus erythrinus | Grey-crowned Rosy-Finch Leucosticte tephrocotis | 1 | 1 | 0 |
| Hooded Siskin Spinus magellanicus | Redpoll Acanthis flammea | 1 | 0 | 1 |
| Lapland Bunting Calcarius lapponicus | Common Grackle Quiscalus quiscula | 1 | 0 | 1 |
| Grasshopper Sparrow Ammodramus savannarum | Field Sparrow Spizella pusilla | 1 | 1 | 0 |
| White-throated Sparrow Zonotrichia albicollis | Sagebrush Sparrow Artemisiospiza nevadensis | 1 | 0 | 1 |
| Vesper Sparrow Pooecetes gramineus | LeConte's Sparrow Ammospiza leconteii | 1 | 0 | 1 |
| Western Meadowlark Sturnella neglecta | Brown-headed Cowbird Molothrus ater | 1 | 1 | 0 |
| Western Meadowlark Sturnella neglecta | Yellow-rumped Warbler Setophaga coronata | 1 | 1 | 0 |
| Nashville Warbler Leiothlypis ruficapilla | MacGillivray's Warbler Geothlypis tolmiei | 1 | 0 | 1 |
| Black-throated Green Warbler Setophaga virens | Wilson's Warbler Cardellina pusilla | 1 | 1 | 0 |
| Greater White-fronted Goose Anser albifrons | Mallard Anas platyrhynchos | 1 | 1 | 0 |
| Painted Bunting Passerina ciris | Blue Dacnis Dacnis cayana | 1 | 0 | 1 |
| Eurasian Wigeon Mareca penelope | American Wigeon Mareca americana | 1 | 0 | 1 |