Case studies (State of the world's birds)

Snow Geese © Rinusbaak/Dreamstime.com

Action is urgently needed to halt human-induced extinction of species and stem the loss of natural habitats. The world’s governments have made commitments through the Convention on Biological Diversity (CBD) to tackle this issue, and the CBD has proposed 20 targets for 2020 in order to focus action. It is vital therefore that simple and effective indicators are developed to track progress towards achieving these targets.

Making sense of indicators Biodiversity indicators are easier to understand, communicate and act upon when linked together in a set that connects policies to outcomes. Four kinds of indicators are needed to make a joined-up set - response indicators, which gauge the impact of policy actions: pressure indicators, which evaluate the threats facing biodiversity; state indicators, which reveal the current status of biodiversity and benefit indicators, which measure how nature contributes to human wellbeing.

To coincide with the tenth Conference of the Parties to the CBD, held in Nagoya, Japan, BirdLife published a booklet entitled Meeting the 2020 biodiversity targets: action and monitoring based on birds. It outlined how the wealth of data available for birds could be used to help set priorities for action and to track the success or failure of society’s response to the unfolding biodiversity crisis. Birds are an ideal indicator group: they are widespread, comparatively well studied, and highly responsive to environmental change (, ).

Birds can provide data for practical, quantitative assessment of our success or failure in preventing extinctions and improving the status of species. The IUCN Red List Index (RLI)—based on data on the movement of species through categories of extinction risk—shows that the status of bird species globally has declined steadily over the last two decades (). Furthermore, the RLI quantifies the net impact of different threats to biodiversity. For example, the impact of overfishing and destructive fishing practices is illustrated by the RLI for seabirds which shows that marine species are more threatened and have declined faster than any other avian group (, ).

Important Bird Areas (IBAs) represent a core set of the most important sites for biodiversity conservation across the globe. The IBA Protection Index measures the degree to which these priority sites are covered by protected areas and provides a useful metric to judge progress in reducing biodiversity loss (). IBA indices show that sites with formal protection are in better and more stable condition than those without (). Currently, only 39% of the area of each IBA is protected on average, and only 26% of sites are completely protected.

Birds are useful indicators of the rate of loss and degradation of different habitats. Wild Bird Indices show that woodland bird populations in Europe have undergone a shallow decline since 1980, whilst farmland birds have declined much more steeply (). In North America, grassland bird populations have declined by over a quarter in the last four decades ().

Birds provide compelling evidence of the impact climate change is already having on biodiversity. A Climatic Impact Index for European birds shows that, over the last two decades, three times as many species have been negatively impacted by climate change than positively affected (). Information from birds can also help develop management frameworks for adapting to climate change. Modelling of the future potential ranges of all ‘priority’ species within southern African IBAs, for instance, suggests that, despite substantial species turnover, the continent’s IBA network will play a key role in mitigating the worst impacts of climate change on birds ().

Biodiversity concerns need to be incorporated into national planning across all sectors of government. Data from birds can be used to ensure this is done effectively, and to monitor the degree to which development is sustainable. For instance, the UK government has adopted an index based on wild bird populations as one of its 15 headline Quality of Life indicators (). Effectively tackling the biodiversity crisis will also rely on building awareness and engendering public support. Birds are spectacularly popular and provide an excellent measure of public engagement with biodiversity. Monitoring the number of people participating in bird-related activities can provide a simple measure of progress in raising environmental awareness ().

CBD Parties are required to prepare National Reports on the status of implementation of the Convention. As conservation priorities for birds are better known than for other species groups, data on birds can help to target national activities on the most urgent issues, species and places. Since the first National Reports were produced in 1998, the emphasis placed on threatened bird species and IBA conservation has increased considerably ().

• Birds are very useful indicators for other kinds of biodiversity
• Most Endemic Bird Areas are in the tropics and important for other biodiversity too
• Birds are found almost everywhere in the world, from the poles to the equator
• Many bird species have very small ranges and occur together in Endemic Bird Areas
• Europe-wide monitoring schemes highlight declines in widespread farmland birds
• The status of the world’s birds has deteriorated over the last 20 years
• Birds have deteriorated in status in all major ecosystems, particularly marine
• Birds in some regions, notably Oceania and Asia, have deteriorated in status faster than others
• Birds in some families, notably seabirds, have deteriorated in status faster than others
• Waterbirds are showing widespread declines, particularly in Asia
• Tracking the impacts of climate change on European birds
• The Red List Index for utilised bird species illustrates their deterioration in status
• The Red List Index for internationally traded bird species shows their deterioration in status
• Seabirds are key indicators of the impact of climate change on the world’s oceans
• Bird indicators make a major contribution to measuring the 2010 target
• Birds as a 'Quality of Life' indicator in the United Kingdom
• The IBA Protection Index tracks trends in the protection of key areas for biodiversity
• Birds are valuable indicators of global patterns in biodiversity
• Monitoring Important Bird Areas in Africa
• Membership of bird conservation organisations is growing world-wide
• Safeguarding Important Bird Areas is key to tackling conservation in the face of climate change
• Grassland birds are declining in North America
• In Kenya, IBA monitoring shows the value of formal protection for biodiversity conservation
• Most threatened birds are deteriorating in status

   

References and external web links

Butchart, S. H. M., Stattersfield, A. J., Bennun, L. A., Shutes, S. M., Akçakaya, H. R., Baillie, J. E. M., Stuart, S. N., Hilton-Taylor, C. and Mace, G. M. (2004) Measuring global trends in the status of biodiversity: Red List Indices for birds. PLoS Biol. 2(12): e383. doi:10.1371/journal.pbio.0020383

Butchart, S. H. M., Akçakaya, H. R., Chanson,J., Baillie, J. E. M., Collen, B., Quader, S., Turner, W. R., Amin, R., Stuart, S. N.,Hilton-Taylor, C. and Mace, G. M. (2007) Improvements to the Red List Index. PLoS ONE 2(1): e140. doi:10.1371/journal.pone.0000140

Butchart, S. H. M., Walpole, M., Collen, B., van Strien, A., Scharlemann, J. P. W., Almond, R. E. E., Baillie, J. E. M., Bomhard, B., Brown, C., Bruno, J., Carpenter, K. E., Carr, G. M., Chanson, J., Chenery, A. M., Csirke, J., Davidson, N. C., Dentener, F., Foster, M., Galli, A., Galloway, J. N., Genovesi, P., Gregory, R. D., Hockings, M., Kapos, V., Lamarque, J.-F., Leverington, F., Loh, J., McGeoch, M. A., McRae, L., Minasyan, A., Morcillo, M. H., Oldfield, T. E. E., Pauly, D., Quader, S., Revenga, C., Sauer, J. R., Skolnik, B., Spear, D., Stanwell-Smith, D., Stuart, S. N., Symes, A., Tierney, M., Tyrrell, T. D., Vié, J. C. and Watson, R. (2010) Global biodiversity: indicators of recent declines. Science 328: 1164-1168. Available from http://www.twentyten.net/2010bippublications

McGeoch, M. A., Butchart, S. H. M., Spear, D., Marais, E., Kleynhans, E. J., Symes, A., Chanson, J. and Hoffmann, M. (2010) Global indicators of biological invasion: species numbers, biodiversity impact and policy responses. Divers. Distrib. 16: 95-108.

Mwangi, M. A. K., Butchart, S. H. M., Barasa, F., Bennun, L. A, Evans, M. I., Fishpool, L. D. C., Kanyanya, E., Madindou, I., Machekele, J., Matiku, P., Mulwa, R., Ngari, A., Stattersfield, A. J. and Siele, J. (2010) Tracking trends in key sites for biodiversity: a case study using Important Bird Areas in Kenya. Bird Conserv. Int. 20: 215–230.

2010 Biodiversity Indicators Partnership

Convention on Biological Diversity

Pan-European Common Bird Monitoring Scheme (PECBMS)

Compiled 2010

Recommended citation
BirdLife International (2010) Spotlight on birds as indicators. Presented as part of the BirdLife State of the world's birds website. Available from: http://www.birdlife.org/datazone