Results

The latest BBS report includes an annual update of population trends, specifically along waterways, for 24 species with the strongest association with that habitat type. These trends are repeated in the table below. Trends are derived from the entire WBBS data sets, and date back to 1999.

The trends below are taken from the latest Breeding Bird Survey Report.

See BirdTrends for details of methodology and a discussion of each species' results in a wider context.

Species Sample 2016-2017 Sig 1999-2016 Sig LCL UCL
Canada Goose 99 -13 60 -7 189
Greylag Goose 54 10 64 -13 233
Mute Swan 112 -1 -15 -37 18
Mallard 234 7 -2 -14 10
Tufted Duck 44 -26 -45 -66 7
Goosander 54 26 27 -13 84
(Grey Heron) 175 9 -26 * -38 -16
(Cormorant) 67 108 17 -25 61
Moorhen 147 -3 -23 * -36 -9
Coot 70 -13 -28 -58 5
Oystercatcher 76 1 -33 * -45 -15
Lapwing 81 -2 -55 * -67 -34
Curlew 62 -12 -50 * -66 -30
Common Sandpiper 69 3 -29 * -42 -16
(Common Tern) 31 -2 -13 -40 24
Kingfisher 72 13 -19 -38 2
Sand Martin 76 19 13 -34 84
Sedge Warbler 92 -28 -53 * -61 -40
Reed Warbler 57 -7 -9 -30 16
Whitethroat 129 0 20 * 4 42
Dipper 91 -6 -8 -25 18
Grey Wagtail 129 -10 -5 -22 13
Pied Wagtail 157 1 -25 * -39 -4
Reed Bunting 112 -13 -7 -19 11

This tables shows percentage changes in bird populations during the specified period.

Trends are marked with an asterisk (*) where the 95% confidence limits of the change do not overlap zero (indicating that there has been a significant change).

The trend since the start of the survey, covering the years 1998–2017, has been smoothed, and the end years truncated. This trend is labelled as Change 99–16.

The sample is the mean number of squares per year on which the species was recorded during 1998–2017.

LCL and UCL are the lower and upper 95% confidence limits for the 1999–2016 change.

Trends for species in brackets are reported with caveats: Cormorant, Grey Heron and Common Tern are reported with the caveat that counts may contain a high proportion of birds away from breeding sites.