Numbers of wintering waterbirds in Great Britain and the Isle of Man (1994/1995–1998/1999): II. Coastal waders (Charadrii)

摘要: Abstract Great Britain's wintering coastal wader populations have been estimated for the period 1994/1995–1998/1999 from data provided two sources: Wetland Bird Survey (WeBS) and Non-estuarine Coastal Waterfowl (UK-NEWS). New methodology estimating number of waders is applied. It imputes (fills in) value missing counts before population size each species as being mean largest annual count made between November March over relevant 5-year period. This has led to an 11% larger estimate present on coasts than traditional approach based averaging just January a period, it suggests that coastline supports ca. 2.1 million waders. Updated values are presented which site evaluations 1% national can be derived. Britain considerable international importance holds >25 >50% flyway nine four wader, respectively, but first time since start monitoring in early 1970s, historical increase predominantly coming end. Seven 14 shown changes >5% last set 1987/1988–1991/1992 estimates declined numbers. The possible causes fluctuations populations, such climate change changing nutrient inputs waters discussed. There urgent need identify causative factors leading these declines, use new sites should afforded legal protection, action help maintain its internationally important populations. decrease updated Eurasian oystercatcher, example, determine 19 rather 17 worthy statutory protection basis holding or more population.