What is happening to the UK’s woodland birds?

Willow tit numbers have declined by 82% in 25 years. Credit BTO

February 2010. A six year science programme to track the changes in bird populations across the UK, and to investigate the causes of recent declines has been announced by the British Trust for Ornithology and the Joint Nature Conservation Committee. The information that will be collected by the partnership's volunteers over the next six years is estimated to be worth in the region of £49 million. It will be used to shape environmental policy and assess targets set by Government.

Causes of declines in bird populations
Some of the causes of declines in bird populations, such as changes in agricultural practice over the past forty years, are well known but others are poorly understood. Many woodland and migrant birds have declined rapidly over the last 25 years but our understanding of how to reverse these declines is incomplete. The Willow Tit, once a common woodland bird, declined by 82% between 1982-2007 and Spotted Flycatcher, a once frequent garden-nesting summer visitor, declined by 81% over the same period. A key objective of the work will be to identify actions needed to reverse such declines, and to assess the impacts of wider environmental change on biodiversity.

Whilst some progress has been made towards the 2010 target of halting biodiversity loss in the UK, some species continue to decline. It is vitally important to monitor the pressures causing these losses. This new programme will use birds as indicators of environmental change. Birds are useful for this as they are relatively large and so easy to see, they live in a wide range of habitats and respond very quickly to changes to those habitats.

Huw Irranca-Davies, Wildlife Minister said "The value of the information collected by the partnership's volunteers can't be underestimated. Without this army of well-trained and highly motivated citizen scientists, out in our towns and countryside, this enormous logistical challenge would be impossible. The information collected from this study will be vital in helping to inform our future direction."

The BTO - JNCC partnership will:

• Monitor birds that use estuaries and wetlands in winter, and on migration during the spring and autumn, providing information relevant to many internationally important Special Protection Areas, and the often energy related projects that affect these habitats, e.g., the proposed Severn Barrage;
• Monitor breeding birds at 3,000 locations across the UK picking up interactions between birds, agriculture, and forestry as well as climate; 
• Monitor the breeding success, migration, and rates of adult mortality in many bird species to help determine when in their lifecycles population change is occurring; 
• Analyse the data to provide information on which bird populations are changing and the broader environmental factors driving this, and reporting the knowledge gained through innovative web-based systems as well as in the scientific literature.