PECBMS methods

Compiled by Petr Voříšek, Arco Van Strien, Willy Van Strien, Jana Škorpilová, Ian Burfield and Richard D. Gregory

What is new in the 2023 data update?

The most important questions that have been asked about PECBMS methods and interpretation of results are answered on a separate page: Questions and Answers.

Information on the aims & structure of PECBMS, the results, the use, some history, and plans are given on the page About us.

Production of European population trends and indices and indicators: an overview

1. National species indices and trends

1.1 Counting birds
Box Field methods
Box Detectability
Box Selection of sample plots
1.2 Production of national indices and trends
Box Missing values I
Box Trend interpretation and classification

2. Supranational species indices and trends

2.1 Delivery of national data to PECBMS coordination unit
Box Data checks
Box Participating countries
2.2 Combining national data into supranational outputs
Box Missing values II
2.3 Types of supranational results that PECBMS produces

3. Multispecies indicators

Box Species selection and classification

4. Quality control

4.1 On the national level
4.2 At delivery to PECBMS
4.3 For supranational indices and trends
4.4 For multispecies indicators

5. References and further reading