Abundance and distribution of selected species Contact Contact organisation

Abundance and distribution of selected species

Contact

0.1.Contact organisation

0.2.Contact organisation unit

5. Contact mail address

1.Metadata update

1.1.Metadata last certified

1.2.Metadata last posted

1.3.Metadata last update

2.Statistical presentation

2.1.Data description

The indicator is published by the European Environment Agency (EEA) and belongs to the SEBI group of indicators (Streamlining European Biodiversity Indicators).

2.2.Classification system

2.3.Sector coverage

2.4.Statistical concepts and definitions

2.5.Statistical unit

2.6.Statistical population

Common farmland birds, Europe:

Common forest birds, Europe:

Other common birds, Europe:

Widespread species: Ochlodes sylvanus, Anthocharis cardamines, Lycaena phlaeas, Polyommatus icarus, Lasiommata megera, Coenonympha pamphilus and Maniola jurtina.

Specialist species: Erynnis tages, Thymelicus action, Spialia Sertorius, Cupido minimus, Maculinea arion, Maculinea nausithous, Polyommatus bellargus, Polyommatus semiargus, Polyommatus coridon and Euphydryas aurinia (EEA, 2010)

2.7.Reference area

2.8.Time coverage

Latest reference year available: 2006 (birds), 2007 (butterflies).

2.9.Base period

3.Unit of measure

• 
  number of common / farmland / forest birds and
  
• 
  number of grassland butterflies
  

4.Reference period

5.Institutional mandate

5.1.Legal acts and other agreements

5.2. Data sharing

6.Confidentiality

6.1.Confidentiality – policy

6.2.Confidentiality - data treatment

7.Release policy

7.1.Release calendar

7.2.Release calendar access

7.3.User access

8.Frequency of dissemination

9.Dissemination format

9.1.News release

9.2.Publications

9.3.On-line database

9.4.Micro-data access

9.5.Other

10.Accessibility of documentation

10.1.Documentation on methodology

BirdLife International (2004). Birds in Europe: population estimates, trends and conservation status. Cambridge, United Kingdom: BirdLife International (BirdLife Conservation Series No. 12).

Donald, P. F., Sanderson, F. J., Burfield, I. J., van Bommel, F. P. J. (2006). Further evidence of continent-wide impacts of agricultural intensification on European farmland birds, 1990-2000. Agriculture, Ecosystems and Environment 116 (2006) 189-196.

Gregory, R. D., van Strien, A., Vorisek, P., Meyling, A. W. G., Noble, D. G., Foppen, R. P. B. and Gibbons, D. W. (2005) Developing indicators for European birds. Phil.Trans. R. Soc. B. 360, 269-288.

Sanderson, F. J., Donald, P. F., Paina, D. J., Burfield, I. J., van Bommel, F. P. J. (2006). Long-term population declines in Afro-Palearctic migrant birds. Biological Conservation 131 (2006) 93-105.

Snow, D. W., Perrins, C. M., (1998). The Birds of the Western Palearctic: Concise Edition. Oxford University Press, Oxford, United Kingdom. Strategy for the Wider Environment. BirdLife International, Cambridge, United Kingdom.

Tucker, G. M., Evans, M. I., (1997). Habitats for Birds in Europe: A Conservation.

b. butterflies

Donald, P. F.; Sanderson, F. J.; Burfield, I. J.; Bierman, S. M.; Gregory, R. D.; and Waliczky, Z., 2007. 'International Conservation Policy Delivers Benefits for Birds in Europe'. Science 317: 810

Feest, A. (2006) Establishing baseline indices for the environmental quality of the biodiversity of restored habitats using a standardised sampling process. Restoration Ecology, 14:112-122.

Gregory, R. D., Van Strien, A. J., Vorisek, P., Gmelig Meyling, A. W., Noble, D. G., Foppen, R. P. B. and Gibbons, D. W. (2005) Developing indicators for European birds. Phil. Trans. R. Soc. B. 360, 269-288.

Pannekoek, J. and Van Strien, A. J. (2003) TRIM 3 manual. Trends and Indices for Monitoring data. CBS, Statistics Netherlands, Voorburg, Netherlands.

Pollard, E. and Yates, T. J. (1995) Monitoring butterflies for ecology and conservation. Chapman and Hall, Londen.

Thomas, J. A., Telfer, M. G., Roy, D. B., Preston, C. D., Greenwood, J. J. D., Asher, J., Fox, R., Clarke, R. T. and Lawton, J. H. (2004) Comparitive losses of British Butterflies, Birds, and Plants and the Global Extinction Crisis. Science 303, 1879-1881.

Thomas, J. A. (2005) Monitoring change in the abundance and distribution of insects using butterflies and other indicator groups. Phil. Trans. Soc. B. 360, 339-357.

Van Strien, A. J., Pannekoek, J. and Gibbons, D. W. (2001) Indexing European bird population trends using results of national monitoring schemes: a trial of a new method. Bird Study 48, 200-213.

Van Swaay, C. A. M. and Warren, M. S. (1999) Red Data Book of European Butterflies (Rhopalocera). Nature and Environment series, No. 99, Council of Europe, Strasbourg.

Van Swaay, C. A. M., Nowicki, P., Settele, J., van Strien, A.J. (2008) Butterfly monitoring in Europe: methods, applications and perspectives, Biodivers Conserv DOI 10.1007/s10531-008-9491-4

Van Swaay, C. A. M., van Strien, A.J. (2005) Using butterfly monitoring data to develop a European grassland butterfly indicator. In Proceeding Studies on the ecology and conservation of Butterfliesin Europe, december 2005

10.2.Quality documentation

11.Quality management

11.1.Quality assurance

11.2.Quality assessment

12.Relevance

12.1.User needs

Have declines in common species in Europe been halted?

Birds and butterflies can be excellent barometers of the health of the environment. They occur in many habitats, can reflect changes in other animals and plants, and are sensitive to environmental change (EEA, 2010/Biodiversity relevance).

This indicator reports on birds and butterflies, familiar groups of species and well known to the public. The Common Birds indicator has already been adopted by the European Union as a structural indicator, a sustainable development indicator and as a baseline indicator under the Rural Development Regulation (Council Regulation (EC) No 1698/2005). It was recommended for immediate use by the European Academics Science Advisory Council (EEA, 2010/Broad acceptance and understandability).

Common birds

Composite population trend indicators, such as the common bird index, provide a tangible basis for measuring progress towards the European target of halting biodiversity loss by 2010, and thus towards the global target of reducing the current rate of biodiversity loss by 2010. The strength of this approach is its simplicity, statistical rigor, sensitivity to change, and ease of update (which is possible annually).

Insects are by far the most species-rich group of animals, representing over 50 % of terrestrial biodiversity. Contrary to most other groups of insects, butterflies are well documented, easy to recognize and popular with the general public. Butterflies use the landscape at a fine scale and react quickly to changes in management, intensification or abandonment. Furthermore, a sustainable butterfly population relies on a network of breeding habitats scattered over the landscape, where species exist in a metapopulation structure. This makes butterflies especially vulnerable to habitat fragmentation. Moreover, many butterflies are highly sensitive to climate change and nitrogen deposition and, because data from fine-scale mapping is available in many countries, they have been used in models predicting the impact of climate change on wildlife. Butterflies have been counted in Butterfly Monitoring Schemes since 1976 (EEA, 2010/Context).

12.2.User satisfaction

12.3.Completeness

13.Accuracy and reliability

13.1.Overall accuracy

The overall accuracy can be considered as high.

Trend information is derived from annually operated national breeding bird surveys spanning different periods from 21 European countries, obtained through the Pan-European Common Bird Monitoring scheme (PECBM). A software package named TRIM (Trends and Indices for Monitoring data) (which allows for missing counts in the time series and yields unbiased yearly indices and standard errors using Poisson regression) is used to calculate national species' indices and then to combine these into supranational indices for species, weighted by estimates of national population sizes. Weighting allows for the fact that different countries hold different proportions of each species' European population. Updated population size estimates, derived from BirdLife International (2004) are used for weighting. Although national schemes differ in count methods in the field, these differences do not influence the supranational results because the indices are standardised before being combined. An improved hierarchical imputation procedure was introduced in 2005 to calculate supranational indices. Supranational indices for species were then combined on a geometric scale to create multi-species indicators.

Butterflies

The overall accuracy can be considered as high.

The field method is based on the British Butterfly Monitoring Scheme (Pollard and Yates, 1993), in use in the United Kingdom since 1976. Counts are made on a line transect of 5 or 10 m wide with homogeneous vegetation and vegetation structure. From March or April to September or October all butterflies 2.5 m to the left and right of the recorder and 5 m in front and above should be counted under standardised weather conditions. The frequency varies from weekly to three or four visits during the season. Most of the sites are recorded by skilled volunteers. All recorders have a good knowledge of the butterfly fauna at their transect and their results are checked by butterfly experts. The main objective of the monitoring schemes is to assess changes in abundance at national and regional levels of butterflies, including species of the Habitat Directive. A European index and trend is produced for each species by combining national results for that species. The individual European species indices are combined (averaged) to create multi-species supranational indicators. This method is based on the one for bird indicators.

13.2.Sampling error

13.3.Non-sampling error

14.Timeliness and punctuality

14.1.Timeliness

14.2.Punctuality

15.Comparability

15.1.Comparability – geographical

The comparability across countries is high - 20 countries, reflecting the availability of high-quality monitoring data from annually-operated PECBM schemes, employing generic survey methods and producing reliable national trends.

Spatial coverage: coverage of western and central Europe is now almost complete, but a few gaps remain, and a further expansion eastwards is desired; efforts to fill them are underway.

Butterflies

The comparability across countries is limited because of geographical coverage.

15.2.Comparability - over time

Until the early 1990s, rather few European countries had common bird monitoring schemes in place, which restricts how far back in time representative trends can be calculated.

The comparability over time is restricted.

16.Coherence

16.1.Coherence - cross domain

16.2.Coherence – internal

• 
  EEA: Red List Index for European species (SEBI 002)
  
• 
  EEA: Species of European interest (SEBI 003)
  
• 
  EEA: Ecosystem coverage(SEBI 004)
  
• 
  EEA: Habitats of European interest (SEBI 005)
  
• 
  EEA: Livestock genetic diversity (SEBI 006)
  
• 
  EEA: Nationally designated protected areas (SEBI 007)
  
• 
  EEA: Sites designated under the EU Habitats and Birds Directives (SEBI 008)
  
• 
  EEA: Impact of climate change on bird populations (SEBI 011)
  

SEBI 004 Ecosystem coverage provides information on how much of the ecosystem is left (quantity), whereas the European birds and butterflies indicators (SEBI 001) and the 'Red List Index' (SEBI 002) provide information on the remaining (average) quality within these ecosystems.

• 
  Eurostat: Common bird index (tsdnr100)
  
• 
  Eurostat: Farmland Bird Index (tsien170)
  
• 
  EEA: Species diversity(CSI 009)
  

17.Cost and burden

18.Data revision

18.1.Data revision – policy

18.2.Data revision – practice

19.Statistical processing

19.1.Source data

Link to the data source: Common birds in Europe, Trends of common birds in Europe

Link to the data source: Data Zone, World Bird Database

Link to the data source: Birds by name

Link to the data source: Grassland butterflies

19.2.Frequency of data collection

19.3.Data collection

Trend information is derived from annually operated national breeding bird surveys spanning different periods from 18 European countries, obtained through the Pan-European Common Bird Monitoring scheme (PECBM). The PECBM scheme is a partnership involving the European Bird Census Council, the Royal Society for the Protection of Birds, BirdLife International and Statistics Netherlands that aims to deliver policy relevant biodiversity indicators for Europe. A software package named TRIM (Trends and Indices for Monitoring data) (which allows for missing counts in the time series and yields unbiased yearly indices and standard errors using Poisson regression) is used to calculate national species' indices and then to combine these into supranational indices for species, weighted by estimates of national population sizes. Weighting allows for the fact that different countries hold different proportions of each species' European population. Updated population size estimates, derived from BirdLife International (2004) are used for weighting. Although national schemes differ in count methods in the field, these differences do not influence the supranational results because the indices are standardised before being combined. An improved hierarchical imputation procedure was introduced in 2005 to calculate supranational indices. Supranational indices for species were then combined on a geometric scale to create multi-species indicators.

For the indicator as produced in June 2005, the species selection was based on BirdLife's Habitats for birds in Europe (Tucker and Evans 1997) - arguably the most comprehensive treatment of habitats and habitat use by birds. It quantitatively assesses the proportion of each species' population that occurs in predefined habitat types across Europe. The overall assessment, while mostly quantitative, also relied to some degree on expert judgment through habitat working groups.

In the PECBM scheme, species were classified to habitat using the assessment of Tucker and Evans (1997), with the exception that montane grassland, (originally included as a sub-class of agricultural habitats) was classified as a separate habitat. All species with more than 75 % of their population occurring in one of the following eight habitats were classified as specialists of that habitat: marine; coastal; inland wetland; tundra, mires and moorland; boreal and temperate forests; Mediterranean forest, shrubland and rocky habitats; agricultural and grassland (excluding montane grassland); and montane grassland (Tucker and Evans 1997).

In addition, species with 10-75 % of their population using only one of the above were classed as specialists in that habitat, according either to Tucker and Evans (1997) for Species of European Conservation Concern (SPECs), or according to the description of Snow and Perrins (1998) for non-SPECs. Species with 10-75 % of their population in three or more woodland or farmland sub-categories in Tucker and Evans (1997) and 10 - 75 % of their population in only one other habitat category were classified as woodland or farmland specialist species respectively.

Remaining species with more than 10 % of their population occurring on more than one habitat were classed as non-specialists. Any species that did not meet the above criteria (due to insufficient data) remained unclassified. Tucker and Evans (1997) include a further habitat of lowland Atlantic heathland; however, no species met the criteria to be classed as a specialist of this habitat.

This species-habitat classification is being used in a number of BirdLife analyses - for example, of farmland birds and long-distance migrants using Bird in Europe 2 trends (Donald et al., 2006; Sanderson et al., 2006). The PECBM scheme also explores a biogeographical approach to species selection and habitat choice knowing that some species may have different habitat preferences according to the biogeographic context.

It should be underlined that the methodology for calculating the farmland bird index has recently changed. The new index presents a much sharper drop around the years of 1995 and 1996. While the new index is recognised as integrating better expertise in terms of species selection, further investigation is necessary to explore what is behind this drop. In addition, the influence of including both new species and the new Member States in the selection, and the starting year of monitoring schemes in some countries should be further investigated. In any case, the trend from 1996 onwards is consistent with the previous methodology and shows the index to be fairly stable.

The field method is based on the British Butterfly Monitoring Scheme (Pollard and Yates, 1993), in use in the United Kingdom since 1976. Counts are made on a line transect of 5 or 10 m wide with homogeneous vegetation and vegetation structure. From March or April to September or October all butterflies 2.5 m to the left and right of the recorder and 5 m in front and above should be counted under standardised weather conditions. The frequency varies from weekly to three or four visits during the season. Most of the sites are recorded by skilled volunteers. All recorders have a good knowledge of the butterfly fauna at their transect, and their results are checked by butterfly experts. Feest (2006) and van Swaay and Feest (in prep.) show that the butterfly survey data can be used to generate biodiversity quality indices for sites such that trends in biodiversity quality can be deduced. This will provide evidence of change more quickly than simple assessments and in a stastically robust way.

The main objective of the monitoring schemes is to assess changes in abundance at national and regional levels of butterflies, including species of the Habitat Directive.

A European index and trend is produced for each species by combining national results for that species. The individual European species indices are combined (averaged) to create multi-species supranational indicators. This method is based on the one for bird indicators (Gregory et al., 2005):

1. At National level: the indices for each species are produced for each country, using TRIM (Pannekoek and Van Strien, 2003). TRIM is a computer programme to analyse time-series of counts with missing observations using Poisson regression.

2. At Supranational level: to generate European trends, the difference in national population size of each species in each country has to be taken into account. This weighting allows for the fact that different countries hold different proportions of a species' European population (Van Strien et al., 2001). A weighting factor is established as the proportion of the country (or region) in the European distribution (Van Swaay and Warren, 1999). The missing year totals are estimated by TRIM in a way equivalent to imputing missing counts for particular sites within countries (Van Strien et al., 2001).

19.4.Data validation

19.5.Data compilation

19.6.Adjustment

20.Comment

Related Metadata

Annex