Focal Area: Status and trends of the components of biodiversity

Headline Indicator: Trends in abundance and distribution of selected species

Key Indicator Partners:      

Regional and National Indicator Partners:

●European Bird Census Council ●National Audubon ●NABCI State of the Birds Subcommittee ●Birds Australia ●Museum National d'Histoire Naturelle ●Czech Society for Ornithology ●Statistics Netherlands ● SOVON ●British Trust for Ornithology ●Lund University ●Dansk Ornitologisk Forening ●BirdWatch Ireland ●BirdLife Austria ●Directorate of Nature Management Norway ●Norwegian Institute of Nature Research ●BirdLife Norway ● Nord-Trøndelag University College ●Swiss Ornithological Institute ●Catalan Ornithological Institute ●Centro Italiano Studi Ornitologici ●LIPU ● FaunaViva ●Aves-Natagora ●Zoological Museum of the Finnish Museum of Natural History ●Finnish Game of Fisheries Research Institute ●Finnish Environmental Institute ●SPEA Latvian Ornithological Society and Latvian Fund for Nature 

Data Available:  Regional/national time series, 1980 onwards

Development Status: Ready for sub global use

There is growing recognition that the inexorable decline of nature may have profound consequences for the lives of people and their economies through the loss of natural resources and the ecological services they provide. Birds can act as excellent sentinels, barometers or indicators of trends in the state of nature and of the sustainability of human land use and environmental health. Birds occur in all habitats, can reflect trends in other animals and plants, and can be sensitive to environmental change. A great deal of high quality data exists on birds and new data are relatively inexpensive to collect.

The Global Wild Bird Index (WBI) will aim to measure population trends of a representative suite of wild birds, to act as a barometer of the general health of the environment and how it is changing. The methodology for producing WBIs is well developed; European WBIs have already been produced and are being used to measure progress towards the European Union’s aim of halting biodiversity loss by 2010. They are used by nearly twenty national governments in Europe within strategies to assess sustainability and environmental health. WBIs have recently been published for North America, and WBI initiatives have begun in Africa and Australia. The WBI measures biodiversity change in a similar fashion to the Living Planet Index, the main difference is that the WBI only incorporates trend data from formally designed breeding bird surveys to deliver scientifically robust and representative indicators. The requirement for robust data, however, means that data coverage is currently patchy and the WBI is not presently applicable at a global scale.

The WBI project aims to promote and encourage the development of WBIs from national population monitoring schemes. Where such schemes already exist, it will coordinate and facilitate the collation of bird species’ data and the generation of indices and indicators. Where there are none, it will provide tools and support to implement similar data collation and synthesis in a representative set of countries across regions, with the funds available to the project. A key tool will be the web-based facility Worldbirds (www.worldbirds.org), which will support the collation of data from bird surveys.

Contributing data are generated at the local level so WBIs are scalable and can be aggregated or disaggregated at the global, regional and national (sub- national) level. WBIs can also be disaggregated by the habitat or guild a bird occurs in, or by aspects of species’ ecology, in order to aid interpretation. WBIs are particularly suited to tracking trends in the condition of habitats.

Provisional Wild Bird Indices for two continental regions, North America and Europe

The indicator is set to a value of100 in 1980.

Source: European Bird Census Council/RSPB/BirdLife International/Statistics Netherlands, and U.S. NABCI Committee. 2009. State of the Birds 2009: United States of America. U.S. Department of Interior: Washington, DC.

The WBI is an average trend in a group of species. They are particularly suited to tracking trends in the condition of habitats. A decrease in the WBI means that the balance of species’ population trends is negative, representing biodiversity loss. If it is constant, there is no overall change. An increase in the WBI means that the balance of species’ trends is positive, implying that biodiversity loss has halted. However, an increasing WBI may, or may not, always equate to an improving situation in the environment. It could in extreme cases be the result of expansion of some species at the cost of others, or reflect habitat degradation. In all cases, detailed analysis must be conducted to interpret accurately the indicator trends. The composite trend can hide important trend patterns for individual species.

 ‘Bird population indices are currently only available from Europe and North America, but a wild bird index combining these data shows that specialist birds have declined by nearly 30% in 40 years.  The largest population declines have occurred in grasslands and arid lands in North America and in farmed lands in Europe, whereas widespread specialists of forests show fluctuating but stable trends. There is the suggestion that bird populations in some of these categories have recovered in the last five years, but we do not know if this trend will continue. The wild bird index project seeks to mobilise relevant information on bird trends globally and encourage the establishment of breeding birds surveys in countries and regions where none exist.’

The Global WBI, which will be built on national data, is still in development. However, national and regions have produced their own WBIs already from national bird monitoring schemes (e.g. Europe and North America) and these data will feed in to the global indicator.

WBIs are being used at a national level in at least 18 European countries, including in Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Latvia, Netherlands, Norway, Portugal, Slovenia, Spain (Catalonia), Sweden, Switzerland, and United Kingdom, and are in development in several others.

New bird monitoring schemes are being initiated in a number of countries in Europe, with the Africa region piloting this approach, but others elsewhere. These will produce data to allow national indicators to be produced, and to contribute to a global WBI in due course.

For more information about producing regional and national Wild Bird Indices,contact Richard Gregory from RSPB (Richard.Gregory@rspb.org.uk) and/or Stuart Butchart from BirdLife International (Stuart.Butchart@birdlife.org).

There is a huge amount of ongoing and historic bird monitoring information (bird surveys and atlases) available across the globe; the challenge is to collate such data and to assess the degree to which it might contribute meaningfully to a global WBI. Information on such bird monitoring programmes and initiatives is being gathered from across the globe by the WBI project. Several new bird-monitoring schemes are being established for example in Africa (e.g. Botswana, Uganda, Rwanda) and China to extend the scope of the WBI project.  Assistance and encouragement is being provided to other countries.  RSPB/BirdLife hopes to run an international WBI workshop in the near future to take this work forwards with indicator partners and other experts. Future Development is funding dependent.