Wildfowl & Wetlands Trust (WWT)

The status of birds in the UK is regularly assessed by a partnership of the UK's leading conservation organisations including WWT.

Each regularly ocurring species is assessed against a set of objective criteria to place each on one of three lists - green, amber and red - indicating an increasing level of conservation concern.

The level of conservation concern helps allocate the scarce resources available to conservation action.

Red list species includes those that are globally threatened, whose population or range has declined rapidly in recent years (i.e. by more than 50% in 25 years), or which have declined historically and not recovered.

Amber list species include those whose population or range has declined moderately in recent years (by more than 25% but less than 50% in 25 years), those whose population has declined historically but recovered recently, rare breeders (fewer than 300 pairs), those with internationally important populations in the UK, those with localised populations and those with an unfavourable conservation status in Europe.

The full list of criteria can be found in the report. Species that meet none of these criteria are green-listed.

Birds of conservation concern 3

On 28 May 2009 the UK's leading bird conservation organisations published the most recent quantitative review of the status of the birds that occur regularly here, updating the last review in 2002.

A glossy summary report is available to download here. The full paper is available from British Birds at www.britishbirds.co.uk

A total of 246 species were assessed. There are 52 species on the red list, 126 on the amber list and 68 on the green list. The red list has increased by 12 since 2002, with 18 species added but six moved from red to amber. Eleven species are now on the red list due to an important change in criteria since the last assessment.

Many farmland and woodland species have failed to recover from declines that led to red listing in the past, with some declining further still.

Amongst the species with increased conservation concern are a number of long-distance migrants such as the cuckoo, tree pipit, yellow wagtail, wood warbler, and three seabirds: the Balearic shearwater, herring gull and Arctic skua (the latter being the only species to move straight from green to red).

A small number of species have shown signs of recovery, with woodlark and stone-curlew moving from the red list to amber in response to targeted conservation action.

Greenland white-fronted goose

Birds of conservation concern 3 took a new approach: focusing attention below the level of species, to races. Such an approach allows the recognition of the importance of the UK for endemic races. The Greenland white-fronted goose Anser albifrons flavirostris has been put straight onto the red list. This is due to such a rapid decline in numbers that it is classified as globally threatened by the IUCN.

WWT's founder, Sir Peter Scott first identified the Greenland race of white-fronted goose in 1947. Since then its existence has been precarious and it is now one of the rarest geese to visit the UK.

The population has suffered a sharp decline - almost 1/3 in 10 years. The causes of this decline are poorly understood. However, two possible causes are suspected:

• increased spring snow cover leaving less room for breeding - climate change is increasing the amount of snow that falls during the winter in Greenland. The snow cover is deeper and stays longer in the spring. This leaves less exposed habitat to support the geese when they return to breed
• increased Canada goose population within those breeding areas is further increasing competition

Common scoter

The common scoter remains on the red list because of a massive decrease in its breeding population. The small UK population which breeds in Scotland decreased by 45% between 1995 and 2007 making it one of the rarest British breeding birds.

Little is know about the common scoter. It lives out at sea during the winter and comes inland to breed. The population which breeds in the UK is far smaller than the population which spends the winter off our coasts. The UK breeding population is confined to Scotland since it became extinct in Northern Ireland.

A count of breeding birds in 2007 found just 52 pairs compared with 95 pairs in 1995. The reasons for the decline are as yet unknown but current theories include:

• climate change related effects - the declines appear to be greatest in the south of their range. Climate change may be causing the annual boom in insect populations, which occurs in the breeding areas in Scotland each summer, to happen at the wrong time to support the chicks
• increase in fish stocks - fish in lochs may be outcompeting the common scoter for their invertebrate prey
• afforestation of the Flow Country - one of the scoters prime breeding areas was heavily forested for commercial reasons in the eighties, acidifying lochs and affecting invertebrate populations