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 |
|---|---|---|---|---|
| White-rumped Sandpiper Calidris fuscicollis | Semipalmated Sandpiper Calidris pusilla | 9 | 2 | 7 |
| Common Tern Sterna hirundo | Roseate Tern Sterna dougallii | 7 | 3 | 4 |
| Sandwich Tern Thalasseus sandvicensis | Royal Tern Thalasseus maximus | 7 | 6 | 1 |
| Short-billed Dowitcher Limnodromus griseus | Long-billed Dowitcher Limnodromus scolopaceus | 7 | 5 | 2 |
| Roseate Tern Sterna dougallii | Sandwich Tern Thalasseus sandvicensis | 6 | 4 | 2 |
| Arctic Skua Stercorarius parasiticus | Pomarine Skua Stercorarius pomarinus | 5 | 3 | 2 |
| Cliff Swallow Petrochelidon pyrrhonota | Cave Swallow Petrochelidon fulva | 5 | 0 | 5 |
| Marbled Godwit Limosa fedoa | Short-billed Dowitcher Limnodromus griseus | 4 | 1 | 3 |
| Puerto Rican Mango Anthracothorax aurulentus | Green-throated Carib Eulampis holosericeus | 4 | 2 | 2 |
| Solitary Sandpiper Tringa solitaria | Greater Yellowlegs Tringa melanoleuca | 4 | 4 | 0 |
| Lesser Antillean Bullfinch Loxigilla noctis | Black-faced Grassquit Melanospiza bicolor | 3 | 2 | 1 |
| Grey Plover Pluvialis squatarola | Wilson's Plover Anarhynchus wilsonia | 3 | 3 | 0 |
| Killdeer Charadrius vociferus | Semipalmated Plover Charadrius semipalmatus | 3 | 2 | 1 |
| Gull-billed Tern Gelochelidon nilotica | White-winged Black Tern Chlidonias leucopterus | 3 | 3 | 0 |
| Grey Plover Pluvialis squatarola | American Golden Plover Pluvialis dominica | 3 | 2 | 1 |
| Common Ground Dove Columbina passerina | Zenaida Dove Zenaida aurita | 3 | 1 | 2 |
| American Bittern Botaurus lentiginosus | Least Bittern Botaurus exilis | 2 | 0 | 2 |
| Bridled Tern Onychoprion anaethetus | Gull-billed Tern Gelochelidon nilotica | 2 | 0 | 2 |
| Western Sandpiper Calidris mauri | Semipalmated Sandpiper Calidris pusilla | 2 | 1 | 1 |
| Grey Plover Pluvialis squatarola | Semipalmated Plover Charadrius semipalmatus | 2 | 1 | 1 |
| Caribbean Martin Progne dominicensis | Cave Swallow Petrochelidon fulva | 2 | 0 | 2 |
| Northern Rough-winged Swallow Stelgidopteryx serripennis | Cave Swallow Petrochelidon fulva | 2 | 0 | 2 |
| Solitary Sandpiper Tringa solitaria | Lesser Yellowlegs Tringa flavipes | 2 | 2 | 0 |
| Lesser Yellowlegs Tringa flavipes | Greater Yellowlegs Tringa melanoleuca | 2 | 2 | 0 |
| Sooty Tern Onychoprion fuscatus | Bridled Tern Onychoprion anaethetus | 2 | 2 | 0 |
| White-cheeked Pintail Anas bahamensis | Ruddy Duck Oxyura jamaicensis | 2 | 1 | 1 |
| Semipalmated Plover Charadrius semipalmatus | Wilson's Plover Anarhynchus wilsonia | 2 | 2 | 0 |
| Puerto Rican Mango Anthracothorax aurulentus | Antillean Crested Hummingbird Orthorhyncus cristatus | 2 | 0 | 2 |
| Orange-crowned Warbler Leiothlypis celata | Connecticut Warbler Oporornis agilis | 2 | 1 | 1 |
| Buff-breasted Sandpiper Calidris subruficollis | Dunlin Calidris alpina | 2 | 0 | 2 |
| Dunlin Calidris alpina | Western Sandpiper Calidris mauri | 2 | 0 | 2 |
| White-faced Whistling-Duck Dendrocygna viduata | West Indian Whistling-Duck Dendrocygna arborea | 2 | 1 | 1 |
| Red-footed Booby Sula sula | Masked Booby Sula dactylatra | 2 | 2 | 0 |
| Semipalmated Sandpiper Calidris pusilla | Western Cattle-Egret Ardea ibis | 1 | 1 | 0 |
| Bonaparte's Gull Chroicocephalus philadelphia | Black-headed Gull Chroicocephalus ridibundus | 1 | 0 | 1 |
| Laughing Gull Leucophaeus atricilla | Magnificent Frigatebird Fregata magnificens | 1 | 0 | 1 |
| Ring-billed Gull Larus delawarensis | Herring Gull Larus argentatus | 1 | 1 | 0 |
| Herring Gull Larus argentatus | Great Black-backed Gull Larus marinus | 1 | 0 | 1 |
| Herring Gull Larus argentatus | Lesser Black-backed Gull Larus fuscus | 1 | 0 | 1 |
| Great Black-backed Gull Larus marinus | Lesser Black-backed Gull Larus fuscus | 1 | 0 | 1 |
| Sooty Tern Onychoprion fuscatus | Black Tern Chlidonias niger | 1 | 1 | 0 |
| Bridled Tern Onychoprion anaethetus | Least Tern Sternula antillarum | 1 | 0 | 1 |
| Bridled Tern Onychoprion anaethetus | Sandwich Tern Thalasseus sandvicensis | 1 | 0 | 1 |
| Least Tern Sternula antillarum | Sandwich Tern Thalasseus sandvicensis | 1 | 1 | 0 |
| Gull-billed Tern Gelochelidon nilotica | Common Tern Sterna hirundo | 1 | 1 | 0 |
| Gull-billed Tern Gelochelidon nilotica | Roseate Tern Sterna dougallii | 1 | 1 | 0 |
| Black Tern Chlidonias niger | Sandwich Tern Thalasseus sandvicensis | 1 | 1 | 0 |
| Common Tern Sterna hirundo | Royal Tern Thalasseus maximus | 1 | 1 | 0 |
| White-tailed Tropicbird Phaethon lepturus | Red-billed Tropicbird Phaethon aethereus | 1 | 1 | 0 |
| Yellow-crowned Night Heron Nyctanassa violacea | Black-crowned Night Heron Nycticorax nycticorax | 1 | 1 | 0 |
| Little Blue Heron Egretta caerulea | Snowy Egret Egretta thula | 1 | 0 | 1 |
| Snowy Egret Egretta thula | Western Cattle-Egret Ardea ibis | 1 | 1 | 0 |
| Great Blue Heron Ardea herodias | Red-tailed Hawk Buteo jamaicensis | 1 | 0 | 1 |
| Caribbean Elaenia Elaenia martinica | Eastern Wood-Pewee Contopus virens | 1 | 0 | 1 |
| Barn Swallow Hirundo rustica | Cave Swallow Petrochelidon fulva | 1 | 0 | 1 |
| Northern Red Bishop Euplectes franciscanus | Bobolink Dolichonyx oryzivorus | 1 | 1 | 0 |
| Northern Red Bishop Euplectes franciscanus | Scarlet Tanager Piranga olivacea | 1 | 1 | 0 |
| Orchard Oriole Icterus spurius | Baltimore Oriole Icterus galbula | 1 | 1 | 0 |
| Venezuelan Troupial Icterus icterus | Baltimore Oriole Icterus galbula | 1 | 1 | 0 |
| Shiny Cowbird Molothrus bonariensis | Greater Antillean Grackle Quiscalus niger | 1 | 0 | 1 |
| Louisiana Waterthrush Parkesia motacilla | Northern Waterthrush Parkesia noveboracensis | 1 | 0 | 1 |
| Northern Waterthrush Parkesia noveboracensis | Cape May Warbler Setophaga tigrina | 1 | 0 | 1 |
| Golden-winged Warbler Vermivora chrysoptera | Blue-winged Warbler Vermivora cyanoptera | 1 | 0 | 1 |
| Black-and-white Warbler Mniotilta varia | Bananaquit Coereba flaveola | 1 | 0 | 1 |
| Connecticut Warbler Oporornis agilis | Common Yellowthroat Geothlypis trichas | 1 | 1 | 0 |
| Kentucky Warbler Geothlypis formosa | Common Yellowthroat Geothlypis trichas | 1 | 0 | 1 |
| American Redstart Setophaga ruticilla | Yellow Warbler Setophaga petechia | 1 | 0 | 1 |
| Cape May Warbler Setophaga tigrina | Magnolia Warbler Setophaga magnolia | 1 | 1 | 0 |
| Northern Parula Setophaga americana | Magnolia Warbler Setophaga magnolia | 1 | 0 | 1 |
| Northern Parula Setophaga americana | Yellow Warbler Setophaga petechia | 1 | 0 | 1 |
| Magnolia Warbler Setophaga magnolia | Yellow Warbler Setophaga petechia | 1 | 1 | 0 |
| Blackburnian Warbler Setophaga fusca | Prairie Warbler Setophaga discolor | 1 | 1 | 0 |
| Yellow Warbler Setophaga petechia | Prairie Warbler Setophaga discolor | 1 | 0 | 1 |
| Yellow-throated Warbler Setophaga dominica | Adelaide's Warbler Setophaga adelaidae | 1 | 0 | 1 |
| Prairie Warbler Setophaga discolor | Adelaide's Warbler Setophaga adelaidae | 1 | 1 | 0 |
| Golden-cheeked Warbler Setophaga chrysoparia | Black-throated Green Warbler Setophaga virens | 1 | 1 | 0 |
| Summer Tanager Piranga rubra | Scarlet Tanager Piranga olivacea | 1 | 0 | 1 |
| Black Tern Chlidonias niger | White-winged Black Tern Chlidonias leucopterus | 1 | 1 | 0 |
| Blue-winged Teal Spatula discors | White-cheeked Pintail Anas bahamensis | 1 | 1 | 0 |
| Northern Shoveler Spatula clypeata | Mallard Anas platyrhynchos | 1 | 1 | 0 |
| Ring-necked Duck Aythya collaris | Lesser Scaup Aythya affinis | 1 | 1 | 0 |
| Lesser Scaup Aythya affinis | Masked Duck Nomonyx dominicus | 1 | 1 | 0 |
| Ruddy Duck Oxyura jamaicensis | Pearly-eyed Thrasher Margarops fuscatus | 1 | 0 | 1 |
| Scaly-naped Pigeon Patagioenas squamosa | Common Ground Dove Columbina passerina | 1 | 0 | 1 |
| Common Ground Dove Columbina passerina | Bridled Quail-Dove Geotrygon mystacea | 1 | 0 | 1 |
| White-winged Dove Zenaida asiatica | Zenaida Dove Zenaida aurita | 1 | 1 | 0 |
| Zenaida Dove Zenaida aurita | Mourning Dove Zenaida macroura | 1 | 0 | 1 |
| Smooth-billed Ani Crotophaga ani | Mangrove Cuckoo Coccyzus minor | 1 | 1 | 0 |
| Yellow-billed Cuckoo Coccyzus americanus | Mangrove Cuckoo Coccyzus minor | 1 | 0 | 1 |
| Common Nighthawk Chordeiles minor | Antillean Nighthawk Chordeiles gundlachii | 1 | 1 | 0 |
| Common Nighthawk Chordeiles minor | Chuck-will's-widow Antrostomus carolinensis | 1 | 1 | 0 |
| Purple-throated Carib Eulampis jugularis | Green-throated Carib Eulampis holosericeus | 1 | 1 | 0 |
| Green-throated Carib Eulampis holosericeus | Antillean Crested Hummingbird Orthorhyncus cristatus | 1 | 0 | 1 |
| Green-throated Carib Eulampis holosericeus | Grey Kingbird Tyrannus dominicensis | 1 | 0 | 1 |
| Antillean Crested Hummingbird Orthorhyncus cristatus | Pearly-eyed Thrasher Margarops fuscatus | 1 | 1 | 0 |
| Killdeer Charadrius vociferus | Wilson's Plover Anarhynchus wilsonia | 1 | 0 | 1 |
| Piping Plover Charadrius melodus | Snowy Plover Anarhynchus nivosus | 1 | 1 | 0 |
| Hudsonian Godwit Limosa haemastica | Marbled Godwit Limosa fedoa | 1 | 0 | 1 |
| Wilson's Snipe Gallinago delicata | Wilson's Phalarope Phalaropus tricolor | 1 | 0 | 1 |
| Spotted Sandpiper Actitis macularius | Solitary Sandpiper Tringa solitaria | 1 | 0 | 1 |
| Spotted Sandpiper Actitis macularius | Willet Tringa semipalmata | 1 | 1 | 0 |
| Willet Tringa semipalmata | Dunlin Calidris alpina | 1 | 0 | 1 |
| Red Knot Calidris canutus | Ruff Calidris pugnax | 1 | 1 | 0 |
| Curlew Sandpiper Calidris ferruginea | Buff-breasted Sandpiper Calidris subruficollis | 1 | 1 | 0 |
| Stilt Sandpiper Calidris himantopus | White-rumped Sandpiper Calidris fuscicollis | 1 | 1 | 0 |
| Stilt Sandpiper Calidris himantopus | Pectoral Sandpiper Calidris melanotos | 1 | 0 | 1 |
| Sanderling Calidris alba | Dunlin Calidris alpina | 1 | 1 | 0 |
| Dunlin Calidris alpina | Semipalmated Sandpiper Calidris pusilla | 1 | 0 | 1 |
| Least Sandpiper Calidris minutilla | Pectoral Sandpiper Calidris melanotos | 1 | 0 | 1 |
| Least Sandpiper Calidris minutilla | Semipalmated Sandpiper Calidris pusilla | 1 | 1 | 0 |