State of the UK's Birds
The theme of The State of the UK's Birds report (SUKB) 2014 is migrants (illustrated by this year’s cover of a Whinchat), a group showing some of the most dramatic population changes in the last few decades.
This includes species like Cuckoo which breed in the UK but spend the winter in Africa, as well as the large numbers of waders and wildfowl that breed further north, but spend their winters on UK coasts and wetlands.
For the summer migrants, where a species spends the winter has a strong influence on its trend. Almost three-quarters (73 %) of migrants such as Nightingale and Wood Warbler that cross the Sahara to winter in the tropical humid zone in West and Central Africa are in decline. In contrast, 56 % of species as Chiffchaff that winter mainly in southern Europe and northern Africa are increasing.
Populations of migrants such as Sedge Warbler that winter in the arid Sahelian zone of Africa are currently relatively stable, although this group has shown massive declines during earlier droughts in this area. These patterns are highlighted by a new migrant indicator. For the winter visitors from the north, the picture is less clear. Although a few species, especially from the Arctic, show declines, the majority of sub-arctic and temperate breeders are stable with 33 % to 40% increasing.
The importance of volunteer data
Volunteer data continue to provide most of the information used to update the trends reported for the UK, the two key examples being the 2500 participants in the Breeding Bird Survey and the Wetland Bird Survey, respectively. The BBS trends highlight six species with severe declines since 1995:Turtle Dove, Willow Tit, Wood Warbler, Grey Partridge, Pied Flycatcher and Whinchat.
Counts by volunteers at more than 2,200 wetland sites at monthly intervals for the Wetland Bird Survey provide the information to report on wintering population trends in 46 species or races of waterbirds including ducks, geese, swans, waders, grebes, rails and cormorants. After two decades of increase, the wintering waterbird indicator has been declining over the last decade, particularly among species such as Turnstone and Purple Sandpiper characteristic of the non-estuarine coasts.
These and other data will also be used in the latest update of the Government’s wild bird indicators. These revealed continuing declines in wetland and waterways birds as well as in seabirds, but no change in already depleted numbers of farmland birds. Woodland species, however, had a relatively good year in 2012.
Scarce and rare breeding species
This year, SUKB includes a summary of trends in scarce and rare breeding species, drawn mainly from the annual reports of the Rare Breeding Bird Panel and the SCARABBS programme of periodic surveys. The results are extremely varied, with marked increases in some very rare species such as Crane and in raptors such as Red Kite, White-tailed Eagle and Hobby, matched by severe declines in a diverse group of species such as Ring Ouzel, Black Redstart, Golden Oriole, Common Scoter and Black Grouse. The table also reveals gaps in knowledge for difficult to survey species such as Hawfinch, Water Rail and Short-eared Owl, and identifies recent colonists such as Great White Egret and Little Bittern whose trends we may soon be able to follow.
A recent national survey of Twite revealed an overall decline in the UK since 1999, particularly marked in England where the population has fallen by more than 70%, but less evident in Scotland. The 2013 Woodcock Survey showed a decline of 29% in this cryptic woodland migrant since 2003, with numbers highest where there are large expanses of woodland.
Who produces the report
SUKB is produced by a coalition of three non-governmental organisations (NGOs) – the RSPB, BTO and the WWT – and the UK Government’s statutory nature conservation agencies – Natural Resources Wales (NRW), Natural England (NE), Northern Ireland Environment Agency (NIEA), Scottish Natural Heritage (SNH) and the Joint Nature Conservation Committee (JNCC).