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The article describes the population density of waterbirds in Great Britain for the period 2004/05 to 2008/09. Collected data showed that species such as Avocet Recurvirostra avosetta, Gadwall Arias strepera and Little Egret Egretta garzetta have increased during the period. Meanwhile, Greenland White-fronted Goose Anser albifrons flavirostris, Dunlin Calidris alpina and Common Pochard Aythya ferina population decreased. The significance of the estimated numbers of non-breeding waterbirds visiting Britain to bird conservation is also noted.

Capsule Both populations are increasing at a similar rate. Aims During 2000, an extensive survey of introduced Greater Canada Geese and re-established Greylag Geese in Great Britain was undertaken in order to update population estimates last made between 1988 and 1991. Methods A randomized stratified sample of 1 329 of the 61 51 0 tetrads (2 km x 2 km unit) in Great Britain was surveyed. The habitat categories, or strata, were based on the proportion of water cover, urbanization, and upland/lowland in each tetrad. Non-urbanized strata were further divided into northern and southern reporting areas. Results In 2000 there were an estimated 88 866 full-grown Greater Canada Geese and 24 522 full- grown Greylag Geese in Great Britain. Since the 1988-9 1 survey, Greater Canada Geese have increased by 166% and Greylag Geese by 1 70%, an average per annum rate of increase of 9.3% for Greater Canada Geese and 9.4% for Greylag Geese. The increase in Greater Canada Goose numbers since the 1988–91 survey has occurred mainly in habitats which had previously held low goose population densities, particularly the ‘no water ’ lowland habitat. Although densities were still relatively low in this habitat (<0.5 geese per km2), because of its extent it supported 56% of the total Greater Canada Goose population in 2000. The greatest increase in re-established Greylag Goose numbers has arisen from an expansion into lowland habitat with some water cover. Conclusion There was no obvious decline in the 8.3% per annum Greater Canada Goose growth rate that caused the population to treble. between 1976 and 1991. Greylag Goose numbers are increasing at a similar rate to those of the Greater Canada Goose. [ABSTRACT FROM AUTHOR]

Capsule The winter distribution of Golden Plover and Lapwing has shifted east since the mid-1980s, perhaps in response to climate change. Aims To combine analyses of winter trends on wetlands and flocks on farmland to assess the current status of Golden Plover and Lapwing in one of their main wintering regions. Methods Winter trends were derived from monthly counts on estuaries and wetlands for the period 1 974-2002 (the Wetland Bird Survey). Winter distribution on farmland was assessed using casual records of large flocks and surveys of a stratified random sample of 1-km squares (the Winter Farmland Bird Survey). Results Regional trends showed a pronounced increase in numbers of both species since i 974 on the east coast, with a smaller increase on the south coast. Numbers in the west and north tended to decline. Flocks on farmland were concentrated in eastern Britain unlike the situation in the 1980s. Conclusions The winter distribution of Golden Plover and Lapwing has shifted to the east, resulting in large numbers on the east coast and in the arable east of Britain. The implications of this shift, especially in relation to known habitat associations, are discussed. [ABSTRACT FROM AUTHOR]

Capsule Population change in geese was assessed using an approach that requires a relatively small sampling effort. Aims During the 1999 breeding season a survey was carried out to determine if the numbers of introduced Canada and re-established Greylag Geese in southern Britain had changed since 1988-91 and whether any change had occurred in areas with previously high or low Canada Goose densities. Methods A randomized stratified sample of 246 tetrads from the 24 156 tetrads covered between 1988-91 in this area, as part of the New Atlas of Breeding Birds, were resurveyed. Eight habitat categories were used in the stratification and were based on 1-km-square summary data obtained from the CEH Land Cover Map of Great Britain (water cover and urbanization) and LANDCLASS stratification (upland/lowland). The five habitat categories with the highest densities of Canada Geese and the greatest variance in numbers were sampled. Results Between 1989 and 1999, the number of Canada Geese on land with over 5% water cover and on lowland with some water cover increased by on average 156%, an average rate of increase of 9.9% per annum. Southern Britain probably now holds a minimum of 82 000 Canada Geese. Between 1989 and 1999, the number of Greylag Geese on land with over 5% water cover and on lowland with some water cover increased by on average 214%, an average rate of increase of 12% per annum. Southern Britain probably now holds a minimum of 30 000 Greylag Geese. Conclusion Maximum densities of Canada Geese may have been reached in high-density habitats but their numbers are still increasing very rapidly. Greylag Geese are increasing even more rapidly. [ABSTRACT FROM AUTHOR]

Regional trends in the populations of waders wintering largely on estuaries were analysed using data collected by the Wetland Bird Surveybetween the winters of 1969/70 and 1995/96 to assess whether trends seen at the national level were repeated across regions of Britain. Not all were. Over this period, the numbers of seven of the 12 species studied increased in south and southeast England, but remained static or declined in southwest England and south Wales. Possible explanations for this are proposed. Increases in the number of Curlews Numenius arquata in the north and northeast of Scotland occurred after 1981/82, when the species stopped being a legal quarry species. A rapiddecline in Oystercatcher Haematopus ostralegus and Knot Cahdris eanutus numbers in east England after 1988/89 may be linked to a change in the Wash shell-fisheries. Warmer winters may be making it less essential for birds to winter in the milder west of Britain. In two pairsof regions, northeast and southeast Scotland, and in northwest England north Wales and northeast England, waders showed similar long-termpopulation changes. The long-term population trends of Oystercatchers in the different regions correlate to those of Ringed Plovers Charadrius hiaticula and Knot, while those of Ringed Plovers are very similar to those of Bar-tailed Godwits Limosa lapponica. In some regions of Britain, the population trends of some species varied a lot between sites, a factor that is an important consideration when determiningthe size and geographical position of regions for future regional indexing. The present separation of regions based on water catchments and geography has given a useful insight into population changes at a finer spatial scale but it could be improved further with added biological input. [ABSTRACT FROM AUTHOR]