Wader populations on the United Kingdom’s open coast: results of the 2015/16 Non-Estuarine Waterbird Survey (NEWS-III) and a review of population trends

Abstract

ABSTRACT Capsule In the winter of 2015/16, the fourth survey of the UK’s wader populations of the open coast – the Non-estuarine Waterbird Survey (NEWS III) – was undertaken. Aim To provide abundance estimates for thirteen key wader species wintering on the open coast alongside a comparison with former surveys and an assessment of abundance change. Methods Counts of all non-breeding waterbirds in the intertidal and landward components of previously designated count stretches of coast were carried out. Abundance estimates were derived with bootstrapped confidence intervals and data from previous surveys re-analysed to allow direct comparison. Generalized linear mixed models were used to assess changes in abundance through paired analyses at a count stretch level across the surveys. Results NEWS III covered 9183 km or 53% of the UK’s non-estuarine coast. The following abundance estimates and confidence limits were calculated (in decreasing order of abundance): Oystercatcher Haematopus ostralegus 69,905 (64,204–75,545), Curlew Numenius arquata 44,344 (38,324–50,613), Turnstone Arenaria interpres 25,988 (23,552–29,324), Dunlin Calidris alpina 19,415 (12,737–26,634), Redshank Tringa totanus 18,513 (17,122–19,758), Golden Plover Pluvialis apricaria 18,513 (11,238–30,825), Lapwing Vanellus vanellus 17,490 (14,148–22,178), Ringed Plover Charadrius hiaticula 16,203 (13,245–18,541), Sanderling Calidris alba 12,903 (10,248–17,268), Purple Sandpiper Calidris maritima 10,184 (7,780–13,945), Bar-tailed Godwit Limosa lapponica 6,217 (4,314–9,501), Knot Calidris canutus 2,683 (1,213–4,484) and Grey Plover Pluvialis squatarola 1,012 (675–1,481). A total of 4,848 (4,097–5,769) was derived for Common Snipe Gallinago gallinago but this is likely to be an underestimate. Overall, four species of waders wintering on the non-estuarine coasts of the UK have decreased or shifted their range since the winter of 2006/07: Lapwing (−57%), Curlew (−31%), Redshank (−37%) and Turnstone (−32%). Only one species increased: Sanderling (+79%). Conclusions The periodic non-estuarine waterbird surveys, alongside the Wetland Bird Survey (WeBS), have been critical in providing population estimates and trends of wintering waterbirds in the UK. More regular monitoring through NEWS, particularly those sites designated for their importance for non-breeding waterbirds, is crucial for understanding why losses of key wader species are occurring and would bring about greater alignment with the WeBS monitoring scheme.