The Wetland Bird Survey (WeBS) is organised nationally by the British Trust for Ornithology and supported by the WWT, RSPB and JNCC. Its principle aims are to identify population sizes, determine trends in numbers and distribution and to identify important sites for waterbirds across the UK.

In 2018 the Hertfordshire counts were organised by Cath Patrick (Lee Valley from Ware south) and Jim Terry (all other sites) and were undertaken by dedicated observers each month. Some sites are not surveyed during the summer months (April to August) but otherwise coverage is most comprehensive.

In 2018 the core count were the following Sundays: 21 Jan, 18 Feb, 18 Mar, 15 Apr, 20 May, 17 Jun, 15 Jul, 12 Aug, 9 Sep, 14 Oct, 11 Nov, 9 Dec. The scheme organisers have agreed that the Lee Valley counts can be undertaken the previous Saturday, and some counts were carried out on the previous or subsequent weekends.

Sincere thanks are due to everyone who contributes to this important monitoring project and especially to Cath and Jim for their co-ordination.

We are always looking for volunteers to assist with this national monitoring effort both to fill any gaps in the existing coverage but also to take on other sites which could hold significant numbers of waterfowl. The effort involves counting all such species at one wetland site each month on Saturday or Sunday. This should ideally happen every month but most importantly from January to March and September to December inclusive. Please contact Jim Terry (46, Manor Way, Borehamwood, Herts, WD6 1QY) or Cath Patrick (c/o LVRP, Myddleton House, Bullís Cross, Enfield, EN2, 9HG) if you are able to help. Thank you.


Mute SwanTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 81 67 56 65 56 31 33 39 46 59 86 66 
Batchworth Lake 0 4 3 4 nc 2 2 2 7 4 7 6 
Stocker's and Bury Lakes 19 20 17 16 15 15 16 21 21 35 40 23 
Maple Lodge NR 0 0 2 2 2 1 0 0 0 0 0 0 
Lynsters Lake 4 nc 1 1 3 2 1 2 6 4 15 10 
Pynesfield North/South Lakes 8 2 1 2 1 2 3 3 5 13 22 27 
Helicon Lake 1 2 0 0 2 2 2 2 2 3 2 0 
Troy Mill Lake 49 39 32 40 33 7 9 9 5 0 0 0 
Lea Valley: 
East Hyde 3 2 7 7 2 4 2 2 2 2 2 2 
Brocket Park 4 4 1 4 4 2 4 4 11 nc 9 0 
Amwell GP - Ware / Thrift GP nc nc nc 1 1 0 2 2 1 2 2 3 
Amwell NR - others nc 4 2 2 3 1 4 nc 6 7 5 7 
Stanstead Abbotts Lakes - N lake 3 4 3 6 1 2 2 8 3 8 10 18 
Rye Meads 4 5 5 nc nc nc nc nc 43 42 35 10 
Broxbourne GP 3 2 1 3 3 1 nc 2 2 1 5 7 
Cheshunt GPs: 
Radwell Mill 16 nc 14 14 nc 11 nc 12 16 16 17 17 
Panshanger Park 2 4 2 2 nc nc nc nc 8 6 5 0 
Fairlands Valley Park 2 2 2 2 2 4 3 3 3 nc 3 2 
Verulamium Park 5 5 5 1 0 2 nc 0 2 9 7 6 
Tyttenhanger GPs - all Present 3 3 9 7 11 Present 10 8 16 12 7 
Hilfield Park Reservoir 0 0 2 3 2 3 9 5 4 4 4 0 
Tring Reservoirs 10 7 nc 4 13 29 38 31 32 nc 19 nc 

Canada GooseTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 155 128 204 143 62 100 157 55 90 47 88 224 
Batchworth Lake 29 25 10 23 nc 0 10 1 8 2 2 28 
Stocker's and Bury Lakes 86 72 99 83 35 92 123 6 11 5 3 96 
Maple Lodge NR 0 31 0 4 4 2 7 0 0 0 0 0 
Lynsters Lake 17 nc 91 28 23 2 1 11 71 23 83 88 
Pynesfield North/South Lakes 0 0 0 0 0 0 0 4 0 0 0 0 
Helicon Lake 22 0 2 4 0 2 14 0 0 17 0 10 
Troy Mill Lake 1 0 2 1 0 2 2 33 0 0 0 2 
Lea Valley: 
East Hyde 6 77 155 57 44 32 48 38 77 121 59 38 
Brocket Park 12 9 24 0 2 0 3 7 5 nc 27 78 
Amwell GP - Ware / Thrift GP nc nc nc 8 2 27 27 0 0 0 0 0 
Amwell NR - others nc 37 73 81 56 17 133 nc 267 0 2 46 
Stanstead Abbotts Lakes - N lake 21 9 25 24 14 28 17 48 0 3 18 8 
Rye Meads 7 0 5 nc nc nc nc nc 10 2 32 1 
Broxbourne GP 0 0 7 2 2 0 nc 0 0 0 5 2 
Cheshunt GPs: 
Radwell Mill 3 nc 6 23 nc 7 nc 5 0 0 0 0 
Panshanger Park 0 4 25 40 nc nc nc nc 0 0 6 9 
Fairlands Valley Park 129 175 79 86 65 220 244 46 58 nc 24 70 
Verulamium Park 21 41 23 9 34 19 nc 6 55 99 25 0 
Tyttenhanger GPs - all 0 37 12 21 24 53 Present 120 129 60 81 104 
Hilfield Park Reservoir 0 0 0 0 2 73 103 80 0 0 13 0 
Tring Reservoirs 10 59 nc 9 21 131 87 161 41 nc 2 nc 

WigeonTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 59 27 4 0 0 0 0 3 0 2 72 54 
Batchworth Lake 0 0 0 0 nc 0 0 0 0 0 0 0 
Stocker's and Bury Lakes 3 0 0 0 0 0 0 1 0 0 14 26 
Maple Lodge NR 0 0 0 0 0 0 0 0 0 0 0 0 
Lynsters Lake 0 nc 0 0 0 0 0 0 0 2 33 0 
Pynesfield North/South Lakes 32 27 4 0 0 0 0 0 0 0 25 25 
Helicon Lake 0 0 0 0 0 0 0 0 0 0 0 3 
Troy Mill Lake 24 0 0 0 0 0 0 2 0 0 0 0 
Lea Valley: 
East Hyde 0 1 2 0 0 0 0 0 0 0 0 0 
Brocket Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Amwell GP - Ware / Thrift GP nc nc nc 0 0 0 0 0 0 0 0 0 
Amwell NR - others nc 0 70 0 0 0 0 nc 0 10 4 13 
Stanstead Abbotts Lakes - N lake 0 0 0 0 0 0 0 0 0 1 0 0 
Rye Meads 0 0 0 nc nc nc nc nc 11 33 1 0 
Broxbourne GP 0 0 0 0 0 0 nc 0 0 0 0 0 
Cheshunt GPs: 
Radwell Mill 0 nc 0 0 nc 0 nc 0 0 0 0 0 
Panshanger Park 31 0 Present 0 nc nc nc nc 2 32 36 4 
Fairlands Valley Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Verulamium Park 0 0 0 0 0 0 nc 0 0 0 0 0 
Tyttenhanger GPs - all 0 0 0 0 0 0 0 0 7 15 5 0 
Hilfield Park Reservoir 12 0 24 0 0 0 0 0 1 Present 0 2 
Tring Reservoirs 86 150 nc 18 0 0 0 0 20 nc 148 nc 

GadwallTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 87 23 18 12 14 31 57 64 21 37 99 91 
Batchworth Lake 0 0 0 0 nc 0 0 0 0 0 0 0 
Stocker's and Bury Lakes 9 4 1 8 5 2 26 31 8 25 44 66 
Maple Lodge NR 2 0 2 4 5 29 31 6 8 0 0 0 
Lynsters Lake 7 nc 2 0 0 0 0 1 0 0 6 6 
Pynesfield North/South Lakes 32 13 10 0 0 0 0 24 5 10 49 17 
Helicon Lake 2 2 2 0 0 0 0 0 0 0 0 1 
Troy Mill Lake 35 4 1 0 4 0 0 2 0 2 0 1 
Lea Valley: 
East Hyde 14 12 14 8 2 0 0 0 2 4 10 12 
Brocket Park 4 0 19 4 0 0 0 0 0 nc 0 0 
Amwell GP - Ware / Thrift GP nc nc nc 2 4 5 28 10 2 0 4 2 
Amwell NR - others nc 7 2 5 9 12 32 nc 23 41 67 126 
Stanstead Abbotts Lakes - N lake 15 34 23 4 6 2 21 81 85 52 97 58 
Rye Meads 117 158 176 nc nc nc nc nc 327 343 118 79 
Broxbourne GP 11 11 3 0 4 0 nc 0 0 4 0 11 
Cheshunt GPs: 
Radwell Mill 0 nc 0 3 nc 0 nc 0 0 1 11 0 
Panshanger Park 179 92 40 23 nc nc nc nc 14 40 102 183 
Fairlands Valley Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Verulamium Park 9 2 4 2 1 0 nc 0 4 53 0 0 
Tyttenhanger GPs - all Present 39 50 29 3 12 Present 40 100 110 80 63 
Hilfield Park Reservoir 13 26 0 8 4 4 76 18 4 17 47 34 
Tring Reservoirs 35 42 nc 15 13 60 127 42 55 nc 49 nc 

TealTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 0 13 13 2 2 0 20 33 79 54 67 29 
Batchworth Lake 0 0 0 0 nc 0 0 0 0 0 0 0 
Stocker's and Bury Lakes 0 0 8 0 0 0 0 0 0 0 0 0 
Maple Lodge NR 0 11 1 2 2 0 20 33 79 54 67 25 
Lynsters Lake 0 nc 0 0 0 0 0 0 0 0 0 0 
Pynesfield North/South Lakes 0 0 0 0 0 0 0 0 0 0 0 4 
Helicon Lake 0 0 0 0 0 0 0 0 0 0 0 0 
Troy Mill Lake 0 2 4 0 0 0 0 0 0 0 0 0 
Lea Valley: 
East Hyde 2 0 2 1 0 0 0 0 0 0 0 2 
Brocket Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Amwell GP - Ware / Thrift GP nc nc nc 0 0 0 0 0 0 0 1 11 
Amwell NR - others nc 7 3 4 0 0 0 nc 1 6 2 6 
Stanstead Abbotts Lakes - N lake 4 2 1 0 0 0 0 0 0 0 3 2 
Rye Meads 117 57 95 nc nc nc nc nc 79 153 59 49 
Broxbourne GP 0 0 0 0 0 0 nc 0 0 0 2 2 
Cheshunt GPs: 
Radwell Mill 0 nc 0 0 nc 0 nc 0 0 0 0 0 
Panshanger Park 82 0 25 1 nc nc nc nc 0 14 11 101 
Fairlands Valley Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Verulamium Park 0 0 0 0 0 0 nc 0 0 0 0 0 
Tyttenhanger GPs - all Present 45 30 22 0 5 0 5 26 60 80 56 
Hilfield Park Reservoir 0 2 3 2 0 0 0 0 3 4 4 0 
Tring Reservoirs 419 198 nc 13 0 0 10 64 194 nc 375 nc 

MallardTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 139 129 103 97 48 86 113 129 110 107 113 157 
Batchworth Lake 20 10 4 15 nc 23 22 20 15 27 15 36 
Stocker's and Bury Lakes 45 64 54 47 23 34 30 25 31 43 30 41 
Maple Lodge NR 27 42 9 11 9 17 48 49 41 7 31 42 
Lynsters Lake 21 nc 18 10 8 9 6 0 0 3 16 5 
Pynesfield North/South Lakes 10 1 8 3 1 0 3 25 7 19 12 7 
Helicon Lake 9 7 3 6 2 2 1 1 16 5 2 19 
Troy Mill Lake 7 5 7 5 5 1 3 9 0 3 7 7 
Lea Valley: 
East Hyde 31 22 17 48 8 10 10 20 18 29 19 17 
Brocket Park 4 6 7 9 0 10 26 9 0 nc 12 4 
Amwell GP - Ware / Thrift GP nc nc nc 3 6 7 15 4 1 13 18 22 
Amwell NR - others nc 29 20 16 14 31 31 nc 13 14 21 43 
Stanstead Abbotts Lakes - N lake 17 9 9 10 15 15 33 26 9 3 33 39 
Rye Meads 93 70 126 nc nc nc nc nc 88 52 71 65 
Broxbourne GP 19 12 17 10 13 14 nc 2 5 4 7 6 
Cheshunt GPs: 
Radwell Mill 31 nc 29 22 nc 26 nc 64 42 56 50 57 
Panshanger Park 66 29 36 43 nc nc nc nc 17 44 24 7 
Fairlands Valley Park 179 107 109 65 73 99 157 236 217 nc 207 202 
Verulamium Park 8 3 12 11 6 15 nc 17 4 9 2 0 
Tyttenhanger GPs - all Present 9 7 9 21 20 Present 36 45 62 63 56 
Hilfield Park Reservoir 3 4 5 10 12 16 8 6 8 15 9 11 
Tring Reservoirs 142 133 nc 78 79 205 305 262 236 nc 119 nc 

ShovelerTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 70 29 12 13 0 0 12 0 12 50 48 21 
Batchworth Lake 0 3 7 0 nc 0 0 0 0 0 0 0 
Stocker's and Bury Lakes 55 12 1 12 0 0 1 0 0 50 1 14 
Maple Lodge NR 4 10 4 0 0 0 11 Present 12 0 7 0 
Lynsters Lake 8 nc 0 0 0 0 0 0 0 0 8 3 
Pynesfield North/South Lakes 0 0 0 0 0 0 0 0 0 0 14 4 
Helicon Lake 0 4 0 0 0 0 0 0 0 0 0 0 
Troy Mill Lake 3 0 0 1 0 0 0 0 0 0 18 0 
Lea Valley: 
East Hyde 0 0 0 0 0 0 0 0 0 0 0 0 
Brocket Park 0 0 2 0 0 0 0 0 0 nc 0 0 
Amwell GP - Ware / Thrift GP nc nc nc 1 0 0 0 0 0 4 2 26 
Amwell NR - others nc 16 6 5 1 1 2 nc 10 8 26 15 
Stanstead Abbotts Lakes - N lake 12 7 5 0 0 0 0 0 2 13 11 8 
Rye Meads 50 35 55 nc nc nc nc nc 78 85 44 164 
Broxbourne GP 2 2 0 0 0 0 nc 0 0 1 4 0 
Cheshunt GPs: 
Radwell Mill 2 nc 0 0 nc 0 nc 0 0 3 1 1 
Panshanger Park 17 8 6 0 nc nc nc nc 1 0 4 Present 
Fairlands Valley Park 0 0 0 0 0 0 0 0 1 nc 0 0 
Verulamium Park 9 2 16 0 0 0 nc 0 0 4 2 2 
Tyttenhanger GPs - all Present 44 35 16 0 0 0 1 16 12 25 16 
Hilfield Park Reservoir 90 77 92 22 0 0 0 0 13 57 45 11 
Tring Reservoirs 78 67 nc 3 0 0 5 12 132 nc 75 nc 

PochardTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 46 59 28 34 21 13 16 20 6 73 82 183 
Batchworth Lake 4 4 5 0 nc 0 0 0 0 0 0 0 
Stocker's and Bury Lakes 20 21 3 19 12 5 4 13 4 62 34 130 
Maple Lodge NR 0 16 3 8 7 7 5 3 2 0 0 0 
Lynsters Lake 5 nc 5 1 0 0 7 4 0 1 1 0 
Pynesfield North/South Lakes 3 13 0 0 0 0 0 0 0 0 7 18 
Helicon Lake 2 1 2 0 0 0 0 0 0 0 0 0 
Troy Mill Lake 12 4 10 6 2 1 0 0 0 10 40 35 
Lea Valley: 
East Hyde 0 0 0 0 0 0 0 0 0 0 0 0 
Brocket Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Amwell GP - Ware / Thrift GP nc nc nc 0 6 2 0 4 0 26 20 24 
Amwell NR - others nc 10 6 8 4 1 11 nc 13 12 14 26 
Stanstead Abbotts Lakes - N lake 2 3 14 8 10 4 1 0 34 41 21 31 
Rye Meads 11 12 32 nc nc nc nc nc 2 1 0 1 
Broxbourne GP 3 1 3 2 0 0 nc 0 0 0 21 60 
Cheshunt GPs: 
Radwell Mill 0 nc 0 0 nc 0 nc 0 0 0 0 0 
Panshanger Park 4 4 6 2 nc nc nc nc 17 25 16 12 
Fairlands Valley Park 0 1 0 0 0 0 0 0 0 nc 0 0 
Verulamium Park 3 10 8 4 0 0 nc 0 0 0 2 4 
Tyttenhanger GPs - all Present 1 7 0 0 0 0 11 15 5 2 3 
Hilfield Park Reservoir 9 5 0 0 0 24 117 27 12 17 5 21 
Tring Reservoirs 120 81 nc 5 4 5 11 16 119 nc 145 nc 

Tufted DuckTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 221 221 230 163 62 158 67 122 46 167 343 301 
Batchworth Lake 11 22 12 25 nc 3 2 1 1 6 15 26 
Stocker's and Bury Lakes 69 89 71 60 40 79 28 94 21 83 168 130 
Maple Lodge NR 4 10 9 13 14 14 10 5 2 0 1 1 
Lynsters Lake 32 nc 58 28 2 7 17 19 6 13 37 38 
Pynesfield North/South Lakes 47 22 19 4 2 18 4 0 10 27 27 38 
Helicon Lake 17 28 14 12 2 7 0 3 6 14 17 12 
Troy Mill Lake 41 50 47 21 2 30 6 0 0 24 78 56 
Lea Valley: 
East Hyde 0 0 0 0 2 2 1 0 2 0 0 0 
Brocket Park 9 13 16 13 10 16 11 2 0 nc 4 3 
Amwell GP - Ware / Thrift GP nc nc nc 63 7 32 24 41 28 61 30 45 
Amwell NR - others nc 97 36 33 37 21 17 nc 28 36 83 70 
Stanstead Abbotts Lakes - N lake 24 53 85 44 22 22 43 72 83 70 109 125 
Rye Meads 38 55 73 nc nc nc nc nc 45 6 7 27 
Broxbourne GP 73 95 115 47 11 9 nc 98 53 21 13 50 
Cheshunt GPs: 
Radwell Mill 0 nc 0 2 nc 2 nc 1 0 0 0 0 
Panshanger Park 40 65 36 36 nc nc nc nc 55 25 31 56 
Fairlands Valley Park 0 0 1 0 0 0 0 0 0 nc 0 0 
Verulamium Park 1 6 8 18 7 4 nc 0 0 0 0 1 
Tyttenhanger GPs - all Present 42 30 15 7 7 Present 12 4 14 17 31 
Hilfield Park Reservoir 69 94 58 74 5 28 122 184 230 80 69 76 
Tring Reservoirs 204 231 nc 0 69 91 180 212 257 nc 188 nc 

GoldeneyeTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 3 15 5 0 0 0 0 1 0 2 2 8 
Batchworth Lake 0 0 0 0 nc 0 0 0 0 0 0 0 
Stocker's and Bury Lakes 2 15 5 0 0 0 0 0 0 0 2 8 
Maple Lodge NR 0 0 0 0 0 0 0 0 0 0 0 0 
Lynsters Lake 0 nc 0 0 0 0 0 0 0 0 0 0 
Pynesfield North/South Lakes 0 0 0 0 0 0 0 0 0 2 0 0 
Helicon Lake 0 0 0 0 0 0 0 1 0 0 0 0 
Troy Mill Lake 1 0 0 0 0 0 0 0 0 0 0 0 
Lea Valley: 
East Hyde 0 0 0 0 0 0 0 0 0 0 0 0 
Brocket Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Amwell GP - Ware / Thrift GP nc nc nc 0 0 0 0 0 0 0 0 0 
Amwell NR - others nc 6 6 2 0 0 0 nc 0 0 0 5 
Stanstead Abbotts Lakes - N lake 0 2 0 0 0 0 0 0 0 0 0 0 
Rye Meads 0 0 0 nc nc nc nc nc 0 0 0 0 
Broxbourne GP 0 0 0 0 0 0 nc 0 0 0 0 0 
Cheshunt GPs: 
Radwell Mill 0 nc 0 0 nc 0 nc 0 0 0 0 0 
Panshanger Park 0 0 0 0 nc nc nc nc 0 0 0 0 
Fairlands Valley Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Verulamium Park 0 0 0 0 0 0 nc 0 0 0 0 0 
Tyttenhanger GPs - all 0 0 0 0 0 0 0 0 0 0 0 0 
Hilfield Park Reservoir 0 1 1 0 0 0 0 0 0 0 1 1 
Tring Reservoirs 4 2 nc 1 0 0 0 0 0 nc 7 nc 

Ruddy DuckTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 0 0 0 0 0 0 0 0 0 0 0 0 
Batchworth Lake 0 0 0 0 nc 0 0 0 0 0 0 0 
Stocker's and Bury Lakes 0 0 0 0 0 0 0 0 0 0 0 0 
Maple Lodge NR 0 0 0 0 0 0 0 0 0 0 0 0 
Lynsters Lake 0 nc 0 0 0 0 0 0 0 0 0 0 
Pynesfield North/South Lakes 0 0 0 0 0 0 0 0 0 0 0 0 
Helicon Lake 0 0 0 0 0 0 0 0 0 0 0 0 
Troy Mill Lake 0 0 0 0 0 0 0 0 0 0 0 0 
Lea Valley: 
East Hyde 0 0 0 0 0 0 0 0 0 0 0 0 
Brocket Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Amwell GP - Ware / Thrift GP nc nc nc 0 0 0 0 0 0 0 0 0 
Amwell NR - others nc 0 0 0 0 0 0 nc 0 0 0 0 
Stanstead Abbotts Lakes - N lake 0 0 0 0 0 0 0 0 0 0 0 0 
Rye Meads 0 0 0 nc nc nc nc nc 0 0 0 0 
Broxbourne GP 0 0 0 0 0 0 nc 0 0 0 0 0 
Cheshunt GPs: 
Radwell Mill 0 nc 0 0 nc 0 nc 0 0 0 0 0 
Panshanger Park 0 0 0 0 nc nc nc nc 0 0 0 0 
Fairlands Valley Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Verulamium Park 0 0 0 0 0 0 nc 0 0 0 0 0 
Tyttenhanger GPs - all 0 0 0 0 0 0 0 0 0 0 0 0 
Hilfield Park Reservoir 0 0 0 0 0 0 0 0 0 0 0 0 
Tring Reservoirs 0 0 nc 0 0 0 0 0 0 nc 0 nc 

Little GrebeTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 2 4 7 10 7 8 8 9 8 6 2 0 
Batchworth Lake 0 0 0 0 nc 0 0 0 0 0 0 0 
Stocker's and Bury Lakes 0 0 1 0 0 0 0 0 0 1 0 0 
Maple Lodge NR 2 4 6 10 7 8 8 9 8 5 2 0 
Lynsters Lake 0 nc 0 0 0 0 0 0 0 0 0 0 
Pynesfield North/South Lakes 0 0 0 0 0 0 0 0 0 0 0 0 
Helicon Lake 0 0 0 0 0 0 0 0 0 0 0 0 
Troy Mill Lake 0 0 0 0 0 0 0 0 0 0 0 0 
Lea Valley: 
East Hyde 1 2 1 2 2 2 2 2 2 0 2 0 
Brocket Park 7 7 3 1 1 4 9 9 9 nc 3 3 
Amwell GP - Ware / Thrift GP nc nc nc 0 0 0 0 0 0 0 0 0 
Amwell NR - others nc 0 0 0 0 0 0 nc 1 0 1 1 
Stanstead Abbotts Lakes - N lake 0 0 0 0 0 0 0 0 0 0 1 0 
Rye Meads 3 9 0 nc nc nc nc nc 38 16 7 4 
Broxbourne GP 1 3 1 0 0 0 nc 0 0 2 4 0 
Cheshunt GPs: 
Radwell Mill 0 nc 0 0 nc 0 nc 0 0 1 5 4 
Panshanger Park 23 14 12 12 nc nc nc nc 36 24 31 30 
Fairlands Valley Park 0 0 0 0 0 0 0 0 0 nc 0 0 
Verulamium Park 0 0 1 0 0 0 nc 1 5 2 0 0 
Tyttenhanger GPs - all 0 0 0 1 0 0 0 1 2 1 0 1 
Hilfield Park Reservoir 1 10 5 1 4 1 1 8 5 5 7 5 
Tring Reservoirs 13 15 nc 2 0 1 5 2 7 nc 15 nc 

Great Crested GrebeTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 38 49 41 41 30 43 42 54 51 49 43 42 
Batchworth Lake 5 10 6 8 nc 4 3 3 4 8 8 10 
Stocker's and Bury Lakes 17 24 16 16 9 15 12 22 19 21 15 13 
Maple Lodge NR 0 0 0 0 2 1 2 0 0 0 0 0 
Lynsters Lake 6 nc 7 3 6 3 7 4 3 6 7 4 
Pynesfield North/South Lakes 2 6 6 4 4 8 6 8 12 10 10 7 
Helicon Lake 3 2 1 2 2 1 2 4 7 1 2 1 
Troy Mill Lake 5 7 5 8 7 11 10 13 6 3 1 7 
Lea Valley: 
East Hyde 0 0 0 0 0 0 0 0 0 0 0 0 
Brocket Park 0 0 1 2 2 1 1 5 2 nc 1 1 
Amwell GP - Ware / Thrift GP nc nc nc 5 5 5 3 8 5 7 5 9 
Amwell NR - others nc 3 3 11 7 4 4 nc 6 9 13 12 
Stanstead Abbotts Lakes - N lake 2 2 6 6 9 3 7 4 10 11 6 8 
Rye Meads 0 0 0 nc nc nc nc nc 8 3 0 0 
Broxbourne GP 4 6 9 10 16 17 nc 15 16 9 14 6 
Cheshunt GPs: 
Radwell Mill 0 nc 0 0 nc 0 nc 0 0 0 0 0 
Panshanger Park 0 8 2 3 nc nc nc nc 2 Present 0 0 
Fairlands Valley Park 3 2 3 1 2 1 0 0 0 nc 1 1 
Verulamium Park 4 3 2 1 0 0 nc 0 0 0 0 0 
Tyttenhanger GPs - all Present 14 8 4 9 6 Present 4 5 11 18 21 
Hilfield Park Reservoir 4 2 4 19 25 29 33 48 49 50 28 27 
Tring Reservoirs 15 14 nc 24 32 33 26 29 26 nc 52 nc 

CormorantTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 41 39 24 7 10 3 5 25 13 30 54 58 
Batchworth Lake 6 4 2 0 nc 0 0 0 0 2 2 13 
Stocker's and Bury Lakes 13 22 16 6 6 2 2 9 10 22 29 18 
Maple Lodge NR 0 1 0 0 2 1 2 2 1 0 0 0 
Lynsters Lake 2 nc 3 0 1 0 1 0 2 1 3 0 
Pynesfield North/South Lakes 3 6 0 1 0 0 0 0 0 2 16 17 
Helicon Lake 1 2 2 0 0 0 0 0 0 0 3 6 
Troy Mill Lake 16 4 1 0 1 0 0 14 0 3 1 4 
Lea Valley: 
East Hyde 5 1 2 3 2 0 1 1 3 0 2 1 
Brocket Park 5 3 2 0 1 1 2 5 4 nc 0 0 
Amwell GP - Ware / Thrift GP nc nc nc 1 0 1 0 0 0 5 0 2 
Amwell NR - others nc 45 44 42 41 37 0 nc 14 56 28 41 
Stanstead Abbotts Lakes - N lake 3 3 0 3 0 3 0 1 8 6 9 14 
Rye Meads 2 0 0 nc nc nc nc nc 24 12 11 2 
Broxbourne GP 8 6 5 6 7 4 nc 3 4 5 23 11 
Cheshunt GPs: 
Radwell Mill 0 nc 0 0 nc 0 nc 1 0 0 0 0 
Panshanger Park 4 4 0 1 nc nc nc nc 3 0 10 Present 
Fairlands Valley Park 6 4 1 1 1 2 4 3 5 nc 6 5 
Verulamium Park 0 0 0 0 0 0 nc 0 0 0 0 0 
Tyttenhanger GPs - all Present 14 3 1 1 3 0 0 1 2 11 9 
Hilfield Park Reservoir 8 1 0 1 0 3 1 4 3 22 57 46 
Tring Reservoirs 30 24 nc 19 24 10 19 32 98 nc 111 nc 

Grey HeronTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 21 20 13 19 10 24 12 13 14 14 12 19 
Batchworth Lake 2 2 1 1 nc 1 2 1 2 0 2 2 
Stocker's and Bury Lakes 13 14 10 17 9 18 2 4 4 3 3 6 
Maple Lodge NR 1 1 0 1 1 4 2 5 2 4 3 1 
Lynsters Lake 1 nc 1 0 0 0 3 0 0 0 1 3 
Pynesfield North/South Lakes 2 2 0 0 0 0 3 1 0 4 1 3 
Helicon Lake 0 0 0 0 0 0 0 0 0 0 0 1 
Troy Mill Lake 2 1 1 0 0 1 0 2 6 3 2 3 
Lea Valley: 
East Hyde 3 2 2 1 1 1 2 1 1 0 1 1 
Brocket Park 3 1 0 1 1 0 0 1 0 nc 0 1 
Amwell GP - Ware / Thrift GP nc nc nc 0 0 0 0 0 0 1 0 0 
Amwell NR - others nc 15 12 13 9 11 5 nc 0 1 4 8 
Stanstead Abbotts Lakes - N lake 1 0 0 0 0 1 1 3 4 2 2 3 
Rye Meads 3 4 2 nc nc nc nc nc 5 4 4 6 
Broxbourne GP 1 3 1 0 0 0 nc 0 0 1 2 0 
Cheshunt GPs: 
Radwell Mill 0 nc 0 0 nc 0 nc 0 1 0 0 0 
Panshanger Park 2 4 0 0 nc nc nc nc 2 0 0 2 
Fairlands Valley Park 0 0 0 0 0 0 1 0 1 nc 0 0 
Verulamium Park 4 0 3 1 1 6 nc 3 3 0 1 1 
Tyttenhanger GPs - all Present 11 4 8 6 15 Present 3 5 5 6 7 
Hilfield Park Reservoir 2 1 0 0 0 0 2 2 1 0 2 4 
Tring Reservoirs 7 18 nc 11 5 10 6 9 19 nc 12 nc 

MoorhenTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 49 50 28 29 13 12 23 38 31 60 50 42 
Batchworth Lake 6 5 2 6 nc 4 1 0 2 7 4 6 
Stocker's and Bury Lakes 24 20 10 8 6 2 7 12 10 15 19 14 
Maple Lodge NR 3 4 5 4 6 4 8 14 11 19 11 9 
Lynsters Lake 2 nc 1 0 0 0 0 4 1 0 0 1 
Pynesfield North/South Lakes 0 3 2 3 1 0 2 1 3 9 6 5 
Helicon Lake 9 6 3 3 0 0 3 2 2 4 6 2 
Troy Mill Lake 5 12 5 5 0 2 2 5 2 6 4 5 
Lea Valley: 
East Hyde 43 14 13 16 8 12 11 14 17 21 12 16 
Brocket Park 22 20 16 6 11 6 6 15 15 nc 20 14 
Amwell GP - Ware / Thrift GP nc nc nc 5 2 2 9 4 9 6 3 7 
Amwell NR - others nc 10 14 6 3 7 8 nc 12 13 14 9 
Stanstead Abbotts Lakes - N lake 3 8 5 4 4 4 4 9 10 5 7 2 
Rye Meads 38 43 46 nc nc nc nc nc 74 91 38 17 
Broxbourne GP 9 9 11 4 1 3 nc 5 8 1 13 4 
Cheshunt GPs: 
Radwell Mill 1 nc 4 1 nc 3 nc 9 12 4 2 0 
Panshanger Park 4 7 5 2 nc nc nc nc 17 8 3 7 
Fairlands Valley Park 39 28 18 21 15 11 15 29 42 nc 38 45 
Verulamium Park 14 4 11 11 3 3 nc 9 5 8 15 10 
Tyttenhanger GPs - all Present 30 5 16 4 7 Present 15 18 19 25 16 
Hilfield Park Reservoir 2 0 1 0 0 0 7 3 1 7 4 2 
Tring Reservoirs 35 23 nc 6 3 6 22 49 72 nc 70 nc 

CootTop of page

JanFebMarAprMayJunJulAugSepOctNovDec 
Colne Valley: 1069 602 662 382 225 204 268 592 624 919 1202 1027 
Batchworth Lake 16 17 17 29 nc 13 28 34 24 22 35 33 
Stocker's and Bury Lakes 262 210 192 128 68 31 34 191 279 540 606 539 
Maple Lodge NR 14 22 24 18 15 15 12 13 15 7 5 2 
Lynsters Lake 205 nc 107 45 36 26 0 47 93 170 312 143 
Pynesfield North/South Lakes 132 89 101 46 31 30 47 74 121 119 158 176 
Helicon Lake 90 48 43 24 17 17 35 33 62 47 76 122 
Troy Mill Lake 350 216 178 92 58 72 112 200 30 14 10 12 
Lea Valley: 
East Hyde 25 12 17 12 12 6 6 10 17 17 17 8 
Brocket Park 67 66 46 31 27 28 39 64 72 nc 96 116 
Amwell GP - Ware / Thrift GP nc nc nc 24 20 16 24 31 24 21 15 7 
Amwell NR - others nc 77 60 36 42 33 83 nc 185 270 278 355 
Stanstead Abbotts Lakes - N lake 99 76 57 37 35 40 30 66 95 224 173 203 
Rye Meads 107 134 122 nc nc nc nc nc 523 319 308 115 
Broxbourne GP 488 343 211 103 89 54 nc 133 99 53 66 87 
Cheshunt GPs: 
Radwell Mill 1 nc 2 3 nc 3 nc 0 0 0 1 1 
Panshanger Park 121 120 104 69 nc nc nc nc 138 166 164 161 
Fairlands Valley Park 33 36 35 19 13 26 28 38 37 nc 40 25 
Verulamium Park 49 64 31 24 23 28 nc 14 10 13 14 9 
Tyttenhanger GPs - all Present 70 40 42 28 25 Present 50 140 105 113 90 
Hilfield Park Reservoir 34 60 54 56 47 76 177 155 136 169 122 35 
Tring Reservoirs 132 139 nc 105 105 293 316 559 608 nc 582 nc