John Lloyd: Britain Year List 2021 BOU, All records: Top Blockers Record(s) 1 to 84 of 84 total.
Seq.	Species	Scientific Name	Seen By Other Listers	Other Listers (%)	
1	Brent Goose	Branta bernicla	359	76.55	
2	Canada Goose	Branta canadensis	460	98.08	
3	Mute Swan	Cygnus olor	461	98.29	
4	Egyptian Goose	Alopochen aegyptiaca	370	78.89	
5	Shelduck	Tadorna tadorna	441	94.03	
6	Wigeon	Mareca penelope	442	94.24	
7	Mallard	Anas platyrhynchos	461	98.29	
8	Pintail	Anas acuta	390	83.16	
9	Teal	Anas crecca	445	94.88	
10	Tufted Duck	Aythya fuligula	457	97.44	
11	Goosander	Mergus merganser	390	83.16	
12	Pheasant	Phasianus colchicus	454	96.80	
13	Red-legged Partridge	Alectoris rufa	400	85.29	
14	Swift	Apus apus	430	91.68	
15	Rock Dove (Feral Pigeon)	Columba livia	403	85.93	
16	Woodpigeon	Columba palumbus	463	98.72	
17	Collared Dove	Streptopelia decaocto	453	96.59	
18	Moorhen	Gallinula chloropus	458	97.65	
19	Coot	Fulica atra	456	97.23	
20	Little Grebe	Tachybaptus ruficollis	443	94.46	
21	Great Crested Grebe	Podiceps cristatus	447	95.31	
22	Oystercatcher	Haematopus ostralegus	448	95.52	
23	Avocet	Recurvirostra avosetta	394	84.01	
24	Grey Plover	Pluvialis squatarola	343	73.13	
25	Ringed Plover	Charadrius hiaticula	399	85.07	
26	Lapwing	Vanellus vanellus	453	96.59	
27	Curlew	Numenius arquata	436	92.96	
28	Redshank	Tringa totanus	434	92.54	
29	Turnstone	Arenaria interpres	411	87.63	
30	Sandwich Tern	Thalasseus sandvicensis	372	79.32	
31	Black-headed Gull	Chroicocephalus ridibundus	460	98.08	
32	Mediterranean Gull	Ichthyaetus melanocephalus	366	78.04	
33	Herring Gull	Larus argentatus	457	97.44	
34	Great Black-backed Gull	Larus marinus	433	92.32	
35	Lesser Black-backed Gull	Larus fuscus	448	95.52	
36	Cormorant	Phalacrocorax carbo	457	97.44	
37	Little Egret	Egretta garzetta	444	94.67	
38	Great White Egret	Ardea alba	387	82.52	
39	Grey Heron	Ardea cinerea	454	96.80	
40	Sparrowhawk	Accipiter nisus	443	94.46	
41	Red Kite	Milvus milvus	434	92.54	
42	Buzzard	Buteo buteo	457	97.44	
43	Kingfisher	Alcedo atthis	410	87.42	
44	Great Spotted Woodpecker	Dendrocopos major	443	94.46	
45	Green Woodpecker	Picus viridis	395	84.22	
46	Kestrel	Falco tinnunculus	453	96.59	
47	Peregrine	Falco peregrinus	421	89.77	
48	Jay	Garrulus glandarius	447	95.31	
49	Magpie	Pica pica	460	98.08	
50	Jackdaw	Coloeus monedula	459	97.87	
51	Rook	Corvus frugilegus	453	96.59	
52	Carrion Crow	Corvus corone	460	98.08	
53	Blue Tit	Cyanistes caeruleus	463	98.72	
54	Great Tit	Parus major	461	98.29	
55	Skylark	Alauda arvensis	440	93.82	
56	Sand Martin	Riparia riparia	426	90.83	
57	Swallow	Hirundo rustica	437	93.18	
58	House Martin	Delichon urbicum	432	92.11	
59	Cetti's Warbler	Cettia cetti	387	82.52	
60	Long-tailed Tit	Aegithalos caudatus	453	96.59	
61	Chiffchaff	Phylloscopus collybita	441	94.03	
62	Reed Warbler	Acrocephalus scirpaceus	399	85.07	
63	Whitethroat	Curruca communis	421	89.77	
64	Goldcrest	Regulus regulus	427	91.04	
65	Wren	Troglodytes troglodytes	458	97.65	
66	Nuthatch	Sitta europaea	431	91.90	
67	Treecreeper	Certhia familiaris	420	89.55	
68	Starling	Sturnus vulgaris	458	97.65	
69	Song Thrush	Turdus philomelos	454	96.80	
70	Mistle Thrush	Turdus viscivorus	437	93.18	
71	Redwing	Turdus iliacus	443	94.46	
72	Blackbird	Turdus merula	462	98.51	
73	Robin	Erithacus rubecula	462	98.51	
74	Stonechat	Saxicola rubicola	432	92.11	
75	Wheatear	Oenanthe oenanthe	409	87.21	
76	House Sparrow	Passer domesticus	458	97.65	
77	Dunnock	Prunella modularis	462	98.51	
78	Grey Wagtail	Motacilla cinerea	440	93.82	
79	Pied Wagtail	Motacilla alba	460	98.08	
80	Meadow Pipit	Anthus pratensis	434	92.54	
81	Chaffinch	Fringilla coelebs	457	97.44	
82	Greenfinch	Chloris chloris	453	96.59	
83	Goldfinch	Carduelis carduelis	454	96.80	
84	Reed Bunting	Emberiza schoeniclus	439	93.60