Terrestrial breeding birds are a good indicator of overall biodiversity. Birds respond quickly to variation in habitat quality, through changes in breeding output, survival or dispersal. Since most bird species are relatively easy to identify and count, are geographically widespread, are abundant and active during daytime, and are extremely well counted and recorded annually, they are often used as indicators of environmental change.
Terrestrial breeding birds in Scotland comprise both resident and migratory species. They include: familiar garden species such as blackbird Turdus merula and robin Erithacus rubecula; woodland species such as willow warbler Phylloscopus trochilus and goldcrest Regulus regulus; farmland species such as linnet Carduelis cannabina and goldfinch Carduelis carduelis; and birds of the uplands such as raven Corvus corax and black grouse Tetrao tetrix.
The key factors include the quality of habitats, farm management practices and environmental change.
Wildlife depends on quality habitats in which to thrive. These habitats provide essential food and shelter and freedom from predation and pollution. Habitat change is a major factor in causing a species population to decrease.
Farm management practices have a large effect on wildlife, so changes in these practices may offer opportunities and threats to biodiversity. We now recognise the importance of achieving a balance between the sensitive management of our natural heritage in order to maintain and enhance that biodiversity. We also recognise the importance of sustaining a viable agricultural industry and of ensuring the long-term viability of rural communities.
Agri-environment management enhances biodiversity in a number of ways, including:
- Measures targeted at protecting and enhancing particular habitats rich in biodiversity, and increasing the functionality of ecosystems, such as the Management of Lowland Raised Bogs measure
- Basic environmental conditions for agricultural support such as field margins and riparian buffers
- Measures, including those supported through the Scotland Rural Development Programme, to promote priority species through targeted changes to land management
Birds, as with other species, are affected by changes in climate. Scientists predict that our biodiversity will be severely compromised by it. Better predictors are available for birds than for other biodiversity.
Just how climate change will affect wildlife is difficult to grasp - and the effects interact. They include:
- Impacts on climate 'space' or the places where favourable climate conditions exist for particular species
- Changes in the timing of seasonal events which can lead to ecological mismatches, such as a lack of food for young birds
- The impacts of extreme weather conditions which, if more harsh and frequent, can affect populations and species
- Changes in community ecology, which may lead to competitive advantages for different species
- Changes in land use and management, where changes in farming, forestry and water management, and many other land uses, are likely to impact on wildlife
Significant contributions will also come from Forestry Commission Scotland and SEPA in their areas of operation. These bodies set priorities and direction, and provide financial support to land owners and others to secure improvement in the condition of habitat features and for priority species. Some of this support will be delivered under the Scotland Rural Development Programme. All public bodies have a statutory duty to further biodiversity conservation as they undertake their functions and responsibilities. Co-ordinated action can also be secured locally through Local Biodiversity Action Plans.
Latest figures show little change in the index of abundance of terrestrial breeding birds between 2014 and 2015. In 2015, the index was 121.3 compared to 119.1 in 2014 (against a value of 100 in 1994).
The data is available at the bottom of the page.
This evaluation is based on: any difference in the index within +/- 3 points of last year's figure suggests that the position is more likely to be maintaining than showing any change. An increase of 3 index points or more suggests the position is improving; whereas a decrease of 3 index points or more suggests the position is worsening.
For information on general methodological approach, please click here.
Scotland Performs Technical Note
Forestry Commission Scotland
Scottish Natural Heritage