Category Archives: HOMEPAGE

Latest update of European wild bird indicators confirms continued decline of farmland birds

The latest data on European common birds, brought together by the Pan-European Common Bird Monitoring Scheme (PECBMS), shows a continued decline of European farmland birds. While the common forest birds are more or less stable over the last 10-15 years, the farmland birds show a staggering decline of 55% since 1980.

Common Farmland Bird Indicator, Europe, 2017 update

Continue reading Latest update of European wild bird indicators confirms continued decline of farmland birds

Questions & Answers

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

Updated on 11 November 2017

In a form of questions and answers, this section aims to help understanding methods of data collation and analysis within the Pan-European Common Bird Monitoring Scheme. The section is complementary to the section Methods. We expect the Questions and Answers will be updated on regular basis and appreciate suggestions for improvements or completely new questions on methods of production and interpretation of supranational species population trends and indicators. Please send comments and suggestions to Petr Voříšek, the PECBMS coordinator,

1. National data sources, field work

2. National species trends and indices (some questions apply to the supranational level too)

3. Supranational species trends and indices (some questions apply to multispecies indicators too)

4. Multispecies indicators: species selection and classification

5. Multispecies indicators: production

6. Multispecies indicators: interpretation

7. References

Trends of common birds in Europe, 2017 update

This report presents an updated population trends and indices of 170 common European bird species for the time period 1980-2015 that have been produced by the Pan-European Common Bird Monitoring Scheme (PECBMS) in 2017. The species trends presented are for long time period (from 1980 onwards until 2015) and for last ten years (2006-2015).
Updated common bird indicators for Europe, EU and their regions for the same time period can be found in a special report.

Continue reading Trends of common birds in Europe, 2017 update

European wild bird indicators, 2017 update

The Pan-European Common Bird Monitoring Scheme (PECBMS) presents a set of updated European wild bird indicators for the time period 1980-2015. The indicators are computed for Europe and its regions (West, North, Central & East and South Europe), and EU, New and Old EU states for common farmland, common forest, and all common birds. Both single European and BioGeo regional species habitat classification are used to assess if each bird species belongs to farmland, forest or other indicator.

Continue reading European wild bird indicators, 2017 update

Report on the Pan-European Common Bird Monitoring Scheme, June 2017

The report summarizes the activities of the Pan-European Common Bird Monitoring Scheme (PECBMS) between January and June 2017. Thanks to the new grant from the European Commission (project „New Generation European Wild Bird Indicators“), PECBMS core activities could re-start again in 2017. The project, led by RSPB in cooperation with CSO will deliver standard supra-national species trends and indicators and will make them available at the web site.

Continue reading Report on the Pan-European Common Bird Monitoring Scheme, June 2017

New study: EU Nature policies reduce but don´t reverse decline of farmland birds

New research, published in Conservation Letters, by a team of conservation researchers, including BirdLife Europe and its partners [1], shows that EU nature legislation and EU agriculture-environment schemes can help to preserve farmland birds, however their impact is weakened by the devastating impact of agriculture intensification. Continue reading New study: EU Nature policies reduce but don´t reverse decline of farmland birds


TRIM (TRends and Indices for Monitoring data) is a program used to determine species’ population trends. It allows for missing counts using estimation, and yields yearly indices and standard errors using Poisson regression. TRIM is a freeware program developed by Statistics Netherlands in the framework of wildlife statistics.

New TRIM – TRIM in R

New version of the programme TRIM which was rebuilt as a package for the freely available and widely used open source statistical program R.

RTRIM contains the same methods and models for nature monitoring data as the original versions of TRIM. It can still work with the same input data and produces exactly the same output data, but as a package in R it can easily be integrated in other R programming processes. As a result of this there is a wider choice in how input data is provided, in how options and settings are chosen and how and what output is provided. New in this version is also the in-built possibility to combine results from other TRIM runs, e.g. to combine results obtained from the analysis of regions of a country into a single new output with a combined trend, indices and standard errors.

Being developed as R-package TRIM is as good as new and is made available for further developments by the large R-society. A development Statistics Netherlands is already working on, is making TRIM suitable for the use of multiple data per year (such as monthly counts). The renewed TRIM is available as RTRIM package on CRAN (Comprehensive R Archive Network).

Users of BirdStats cannot yet use this in combination with RTRIM, but we are working on a solution for that too.

Manual, documentation and helpfiles in the R environment with several programming examples can be found on the CRAN website. For any questions about the use of RTRIM, please contact

Also, RTRIM shell documents have been developed by Statistics Netherlands, which provides calculation and outputs of national species indices in a standardized way. Using this shell makes it easier to process large batches of species with specific model parameters at once. The shell is a combination of several R scripts together with a short user guide and can be downloaded here. Note that the use of covariates in the models is not yet included in this new development, but will be in the future.

See more info about TRIM also on the website of the Statistics Netherlands

Old TRIM – TRIM in Delphi

Old version of the programme TRIM was originally developed some 25 years ago by Statistics Netherlands (Pannekoek and Van Strien, 1991) and was made available as a freeware stand-alone program. The program has had several updates since then, however, the original programming language (Delphi) has become outdated and rendered further developments.

The latest version is TRIM 3.54 (released in 2006) which is designed to run under 32-bits versions of Windows, as Windows98, Windows2000 and WindowsXP.

Warranty Disclaimer. This software and the accompanying documentation is provided “as is”. Statistics Netherlands disclaims all warranties, either expressed or implied.

TRIM can be downloaded from the EBCC website together with a manual, a powerpoint presentation explaining TRIM for first users, and papers using the TRIM method. Alternatively, you can download TRIM as a part of the program BirdSTATs which enables to calculate indices and trends in batch mode to perform the statistical analysis for series of bird counts in the dataset.