David Lindo: North and Middle America Life List AOU, All records: Top Blockers Record(s) 1 to 68 of 68 total.
Seq.	Species	Scientific Name	Seen By Other Listers	Other Listers (%)	
1	Black-bellied Whistling-Duck	Dendrocygna autumnalis	53	48.18	
2	Snow Goose	Anser caerulescens	51	46.36	
3	Ross's Goose	Anser rossii	28	25.45	
4	Brant	Branta bernicla	48	43.64	
5	Cackling Goose	Branta hutchinsii	28	25.45	
6	Canada Goose	Branta canadensis	78	70.91	
7	Mute Swan	Cygnus olor	55	50.00	
8	Trumpeter Swan	Cygnus buccinator	37	33.64	
9	Tundra Swan	Cygnus columbianus	35	31.82	
10	Wood Duck	Aix sponsa	70	63.64	
11	Blue-winged Teal	Spatula discors	67	60.91	
12	Cinnamon Teal	Spatula cyanoptera	43	39.09	
13	Northern Shoveler	Spatula clypeata	72	65.45	
14	Gadwall	Mareca strepera	61	55.45	
15	American Wigeon	Mareca americana	63	57.27	
16	Hawaiian Duck	Anas wyvilliana	9	8.18	
17	Mallard	Anas platyrhynchos	45	40.91	
18	American Black Duck	Anas rubripes	51	46.36	
19	Mottled Duck	Anas fulvigula	39	35.45	
20	Northern Pintail	Anas acuta	60	54.55	
21	Green-winged Teal	Anas crecca	56	50.91	
22	Canvasback	Aythya valisineria	53	48.18	
23	Redhead	Aythya americana	53	48.18	
24	Ring-necked Duck	Aythya collaris	59	53.64	
25	Greater Scaup	Aythya marila	41	37.27	
26	Lesser Scaup	Aythya affinis	59	53.64	
27	Surf Scoter	Melanitta perspicillata	52	47.27	
28	White-winged Scoter	Melanitta deglandi	24	21.82	
29	Black Scoter	Melanitta americana	38	34.55	
30	Long-tailed Duck	Clangula hyemalis	37	33.64	
31	Bufflehead	Bucephala albeola	58	52.73	
32	Hooded Merganser	Lophodytes cucullatus	59	53.64	
33	Common Merganser	Mergus merganser	56	50.91	
34	Red-breasted Merganser	Mergus serrator	63	57.27	
35	Ruddy Duck	Oxyura jamaicensis	59	53.64	
36	Plain Chachalaca	Ortalis vetula	35	31.82	
37	California Quail	Callipepla californica	41	37.27	
38	Gambel's Quail	Callipepla gambelii	30	27.27	
39	Wild Turkey	Meleagris gallopavo	58	52.73	
40	Least Grebe	Tachybaptus dominicus	46	41.82	
41	Pied-billed Grebe	Podilymbus podiceps	77	70.00	
42	Horned Grebe	Podiceps auritus	39	35.45	
43	Eared Grebe	Podiceps nigricollis	48	43.64	
44	Western Grebe	Aechmophorus occidentalis	49	44.55	
45	Clark's Grebe	Aechmophorus clarkii	30	27.27	
46	Rock Pigeon	Columba livia	74	67.27	
47	Band-tailed Pigeon	Patagioenas fasciata	46	41.82	
48	Eurasian Collared-Dove	Streptopelia decaocto	51	46.36	
49	Spotted Dove	Streptopelia chinensis	17	15.45	
50	Inca Dove	Columbina inca	53	48.18	
51	Common Ground Dove	Columbina passerina	64	58.18	
52	White-tipped Dove	Leptotila verreauxi	43	39.09	
53	White-winged Dove	Zenaida asiatica	59	53.64	
54	Mourning Dove	Zenaida macroura	86	78.18	
55	Greater Roadrunner	Geococcyx californianus	40	36.36	
56	Yellow-billed Cuckoo	Coccyzus americanus	37	33.64	
57	Black-billed Cuckoo	Coccyzus erythropthalmus	26	23.64	
58	Lesser Nighthawk	Chordeiles acutipennis	42	38.18	
59	Common Nighthawk	Chordeiles minor	46	41.82	
60	Common Pauraque	Nyctidromus albicollis	38	34.55	
61	Eastern Whip-poor-will	Antrostomus vociferus	17	15.45	
62	Black Swift	Cypseloides niger	26	23.64	
63	Chimney Swift	Chaetura pelagica	65	59.09	
64	Vaux's Swift	Chaetura vauxi	48	43.64	
65	White-throated Swift	Aeronautes saxatalis	41	37.27	
66	Anna's Hummingbird	Calypte anna	49	44.55	
67	Costa's Hummingbird	Calypte costae	29	26.36	
68	Allen's Hummingbird	Selasphorus sasin	24	21.82