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 |
|---|---|---|---|---|
| Greater Scaup Aythya marila | Lesser Scaup Aythya affinis | 2 | 1 | 1 |
| Tennessee Warbler Leiothlypis peregrina | Orange-crowned Warbler Leiothlypis celata | 2 | 1 | 1 |
| Bay-breasted Warbler Setophaga castanea | Blackpoll Warbler Setophaga striata | 2 | 2 | 0 |
| Golden Eagle Aquila chrysaetos | Bald Eagle Haliaeetus leucocephalus | 2 | 2 | 0 |
| Trumpeter Swan Cygnus buccinator | Bewick's Swan Cygnus columbianus | 1 | 0 | 1 |
| Trumpeter Swan Cygnus buccinator | Coscoroba Swan Coscoroba coscoroba | 1 | 1 | 0 |
| Bewick's Swan Cygnus columbianus | Coscoroba Swan Coscoroba coscoroba | 1 | 0 | 1 |
| Egyptian Goose Alopochen aegyptiaca | Muscovy Duck Cairina moschata | 1 | 0 | 1 |
| Common Shelduck Tadorna tadorna | Ringed Teal Callonetta leucophrys | 1 | 0 | 1 |
| Blue-winged Teal Spatula discors | Northern Shoveler Spatula clypeata | 1 | 0 | 1 |
| White-cheeked Pintail Anas bahamensis | Common Ringed Plover Charadrius hiaticula | 1 | 1 | 0 |
| Canvasback Aythya valisineria | Greater Scaup Aythya marila | 1 | 1 | 0 |
| Helmeted Guineafowl Numida meleagris | Northern Bobwhite Colinus virginianus | 1 | 1 | 0 |
| Helmeted Guineafowl Numida meleagris | Wild Turkey Meleagris gallopavo | 1 | 1 | 0 |
| Red Junglefowl Gallus gallus | Blue-breasted Quail Synoicus chinensis | 1 | 0 | 1 |
| Red Junglefowl Gallus gallus | Red-legged Partridge Alectoris rufa | 1 | 1 | 0 |
| American Moorhen Gallinula galeata | Purple Gallinule Porphyrio martinica | 1 | 0 | 1 |
| Sandhill Crane Antigone canadensis | Whooping Crane Grus americana | 1 | 0 | 1 |
| Black-necked Stilt Himantopus mexicanus | American Avocet Recurvirostra americana | 1 | 1 | 0 |
| Common Ringed Plover Charadrius hiaticula | Semipalmated Plover Charadrius semipalmatus | 1 | 1 | 0 |
| Eskimo Curlew Numenius borealis | Long-billed Dowitcher Limnodromus scolopaceus | 1 | 1 | 0 |
| Hudsonian Godwit Limosa haemastica | Long-billed Dowitcher Limnodromus scolopaceus | 1 | 1 | 0 |
| Grey Phalarope Phalaropus fulicarius | Red-necked Phalarope Phalaropus lobatus | 1 | 1 | 0 |
| Solitary Sandpiper Tringa solitaria | Lesser Yellowlegs Tringa flavipes | 1 | 0 | 1 |
| Solitary Sandpiper Tringa solitaria | Willet Tringa semipalmata | 1 | 0 | 1 |
| Ruddy Turnstone Arenaria interpres | Ruff Calidris pugnax | 1 | 1 | 0 |
| Ruff Calidris pugnax | Sanderling Calidris alba | 1 | 1 | 0 |
| Ruff Calidris pugnax | Black Guillemot Cepphus grylle | 1 | 1 | 0 |
| Buff-breasted Sandpiper Calidris subruficollis | White-rumped Sandpiper Calidris fuscicollis | 1 | 0 | 1 |
| Baird's Sandpiper Calidris bairdii | Least Sandpiper Calidris minutilla | 1 | 1 | 0 |
| White-rumped Sandpiper Calidris fuscicollis | Pectoral Sandpiper Calidris melanotos | 1 | 1 | 0 |
| Arctic Skua Stercorarius parasiticus | Pomarine Skua Stercorarius pomarinus | 1 | 0 | 1 |
| Pomarine Skua Stercorarius pomarinus | Buff-bellied Pipit Anthus rubescens | 1 | 1 | 0 |
| Brünnich's Guillemot Uria lomvia | Ancient Murrelet Synthliboramphus antiquus | 1 | 0 | 1 |
| Ivory Gull Pagophila eburnea | Franklin's Gull Leucophaeus pipixcan | 1 | 1 | 0 |
| Bonaparte's Gull Chroicocephalus philadelphia | Franklin's Gull Leucophaeus pipixcan | 1 | 0 | 1 |
| Arctic Tern Sterna paradisaea | Common Tern Sterna hirundo | 1 | 1 | 0 |
| Red-throated Diver Gavia stellata | Pacific Diver Gavia pacifica | 1 | 0 | 1 |
| Northern Fulmar Fulmarus glacialis | Cory's Shearwater Calonectris borealis | 1 | 1 | 0 |
| Golden Eagle Aquila chrysaetos | Rough-legged Buzzard Buteo lagopus | 1 | 0 | 1 |
| Northern Harrier Circus hudsonius | Swainson's Hawk Buteo swainsoni | 1 | 1 | 0 |
| Sharp-shinned Hawk Accipiter striatus | Swainson's Hawk Buteo swainsoni | 1 | 0 | 1 |
| Bald Eagle Haliaeetus leucocephalus | Red-tailed Hawk Buteo jamaicensis | 1 | 0 | 1 |
| Harris's Hawk Parabuteo unicinctus | Broad-winged Hawk Buteo platypterus | 1 | 0 | 1 |
| Harris's Hawk Parabuteo unicinctus | Rough-legged Buzzard Buteo lagopus | 1 | 0 | 1 |
| Downy Woodpecker Dryobates pubescens | Hairy Woodpecker Leuconotopicus villosus | 1 | 0 | 1 |
| Cockatiel Nymphicus hollandicus | Ring-necked Parakeet Psittacula krameri | 1 | 1 | 0 |
| Olive-sided Flycatcher Contopus cooperi | Western Wood-Pewee Contopus sordidulus | 1 | 0 | 1 |
| Yellow-bellied Flycatcher Empidonax flaviventris | Least Flycatcher Empidonax minimus | 1 | 1 | 0 |
| Alder Flycatcher Empidonax alnorum | Willow Flycatcher Empidonax traillii | 1 | 1 | 0 |
| Least Flycatcher Empidonax minimus | White-breasted Nuthatch Sitta carolinensis | 1 | 1 | 0 |
| Eastern Phoebe Sayornis phoebe | Eastern Kingbird Tyrannus tyrannus | 1 | 0 | 1 |
| Blue-headed Vireo Vireo solitarius | Philadelphia Vireo Vireo philadelphicus | 1 | 1 | 0 |
| Canada Jay Perisoreus canadensis | Snow Bunting Plectrophenax nivalis | 1 | 1 | 0 |
| Hooded Crow Corvus cornix | Pied Crow Corvus albus | 1 | 1 | 0 |
| Hooded Crow Corvus cornix | Common Raven Corvus corax | 1 | 0 | 1 |
| Great Tit Parus major | Western Meadowlark Sturnella neglecta | 1 | 1 | 0 |
| Shore Lark Eremophila alpestris | Grey-crowned Rosy-Finch Leucosticte tephrocotis | 1 | 1 | 0 |
| Tree Swallow Tachycineta bicolor | Violet-green Swallow Tachycineta thalassina | 1 | 0 | 1 |
| Barn Swallow Hirundo rustica | Lark Sparrow Chondestes grammacus | 1 | 1 | 0 |
| Barn Swallow Hirundo rustica | Spotted Towhee Pipilo maculatus | 1 | 0 | 1 |
| Cliff Swallow Petrochelidon pyrrhonota | Veery Catharus fuscescens | 1 | 0 | 1 |
| Golden-crowned Kinglet Regulus satrapa | Savannah Sparrow Passerculus sandwichensis | 1 | 1 | 0 |
| Marsh Wren Cistothorus palustris | Fox Sparrow Passerella iliaca | 1 | 1 | 0 |
| Townsend's Solitaire Myadestes townsendi | Blackpoll Warbler Setophaga striata | 1 | 0 | 1 |
| Varied Thrush Ixoreus naevius | American Redstart Setophaga ruticilla | 1 | 1 | 0 |
| Veery Catharus fuscescens | Swainson's Thrush Catharus ustulatus | 1 | 1 | 0 |
| Wood Thrush Hylocichla mustelina | Lark Sparrow Chondestes grammacus | 1 | 0 | 1 |
| Zebra Finch Taeniopygia guttata | Lapland Bunting Calcarius lapponicus | 1 | 0 | 1 |
| Lapland Bunting Calcarius lapponicus | Snow Bunting Plectrophenax nivalis | 1 | 1 | 0 |
| Lapland Bunting Calcarius lapponicus | American Redstart Setophaga ruticilla | 1 | 0 | 1 |
| Smith's Longspur Calcarius pictus | Grasshopper Sparrow Ammodramus savannarum | 1 | 1 | 0 |
| Lark Sparrow Chondestes grammacus | Lark Bunting Calamospiza melanocorys | 1 | 0 | 1 |
| Harris's Sparrow Zonotrichia querula | LeConte's Sparrow Ammospiza leconteii | 1 | 1 | 0 |
| Vesper Sparrow Pooecetes gramineus | Nelson's Sparrow Ammospiza nelsoni | 1 | 1 | 0 |
| Seaside Sparrow Ammospiza maritima | Savannah Sparrow Passerculus sandwichensis | 1 | 1 | 0 |
| Nelson's Sparrow Ammospiza nelsoni | Spotted Towhee Pipilo maculatus | 1 | 0 | 1 |
| Song Sparrow Melospiza melodia | Swamp Sparrow Melospiza georgiana | 1 | 1 | 0 |
| Nashville Warbler Leiothlypis ruficapilla | Mourning Warbler Geothlypis philadelphia | 1 | 0 | 1 |
| Nashville Warbler Leiothlypis ruficapilla | Common Yellowthroat Geothlypis trichas | 1 | 1 | 0 |
| Connecticut Warbler Oporornis agilis | Common Yellowthroat Geothlypis trichas | 1 | 1 | 0 |
| Connecticut Warbler Oporornis agilis | Black-throated Green Warbler Setophaga virens | 1 | 1 | 0 |
| Common Yellowthroat Geothlypis trichas | Canada Warbler Cardellina canadensis | 1 | 0 | 1 |
| Cape May Warbler Setophaga tigrina | Magnolia Warbler Setophaga magnolia | 1 | 1 | 0 |
| Blackburnian Warbler Setophaga fusca | Blackpoll Warbler Setophaga striata | 1 | 1 | 0 |
| Chestnut-sided Warbler Setophaga pensylvanica | Blackpoll Warbler Setophaga striata | 1 | 1 | 0 |
| Black-throated Blue Warbler Setophaga caerulescens | Palm Warbler Setophaga palmarum | 1 | 0 | 1 |
| Palm Warbler Setophaga palmarum | Black-throated Grey Warbler Setophaga nigrescens | 1 | 1 | 0 |
| Prairie Warbler Setophaga discolor | Townsend's Warbler Setophaga townsendi | 1 | 1 | 0 |
| Townsend's Warbler Setophaga townsendi | Canada Warbler Cardellina canadensis | 1 | 0 | 1 |
| Black-throated Green Warbler Setophaga virens | Wilson's Warbler Cardellina pusilla | 1 | 1 | 0 |
| Canada Warbler Cardellina canadensis | Wilson's Warbler Cardellina pusilla | 1 | 0 | 1 |
| Fulvous Whistling-Duck Dendrocygna bicolor | Common Chaffinch Fringilla coelebs | 1 | 0 | 1 |
| American Herring Gull Larus smithsonianus | European Herring Gull Larus argentatus | 1 | 0 | 1 |
| Snow Goose Anser caerulescens | Snow Bunting Plectrophenax nivalis | 1 | 1 | 0 |
| Pink-footed Goose Anser brachyrhynchus | Barnacle Goose Branta leucopsis | 1 | 0 | 1 |
| Cackling Goose Branta hutchinsii | Canada Goose Branta canadensis | 1 | 0 | 1 |