Trends in bird population


THE BRITISH Trust for Ornotholgy has published some material which will be of interest to the many people who enjoy the wildlife at Montrose Basin.

In the journal ‘British Birds’, a team of waterbird experts estimate that 12.5 million waterbirds, of 85 different species, used British coasts and wetlands during the five winters of 2004/5 to 2008/09.

Many of these breed in remote areas of the north, some arriving from as far west as Canada and as far east as Siberia, whilst others remain here all year round. These waterbirds include everything from the resident Mute Swans (74,000) and Grey Herons (61,000) in our local parks, to real globe-trotters such as Bewick’s Swans (7,000) and Turnstones (48,000).

Having reliable estimates of the number of wintering waterbirds visiting Britain is crucial for the birds’ conservation, both for assessing the health of their populations, and for the identification and protection of nationally and internationally important sites (such as the 147 Ramsar sites and 252 Special Protection Areas in Britain).

The newly published paper reveals that the numbers of some wintering species have increased, notably the Gadwall (25,000), Avocet (7,500) and Little Egret (4,500); the latter was considered a national rarity as recently as 1990. Some non-native introduced species have also increased, with an estimated 190,000 Canada Geese now at large in Britain. However, a number of others have declined alarmingly, causing concern for birds such as the Greenland White-fronted Goose (13,000), Dunlin (350,000) and Pochard (38,000).

The most numerous wintering waterbird in Britain is revealed to be the Black-headed Gull, with an estimated 2,200,000 flooding in from across northern Europe to spend the winter with us. At the other end of the scale, only about 20 Spoonbills typically spend the winter in Britain, mostly on estuaries along the milder south coast.