Ian J. Burfield

The generation and use of bird population indicators in Europe

Global and regional targets to reduce the rate of biodiversity loss bring with them the need to measure the state of nature and how it is changing. A number of different biodiversity indicators have been developed in response and here we consider bird population indicators in Europe. Birds are often used as surrogates for other elements of biodiversity because they are so well known and well studied, and not for their unique intrinsic value as environmental indicators. Yet, in certain situations and at particular scales, trends in bird populations correlate with those of other taxa making them a valuable biodiversity indicator with appropriate caveats. In this paper, we look at two case studies, in the UK and Europe as a whole, where headline bird indicators, that is, summary statistics based on bird population trends, have been developed and used to inform and assist policy makers. Wild bird indicators have been adopted by many European countries and by the European Union as indicators of biodiversity and of sustainable development. In the discussion, we review the strengths and weaknesses of using bird populations in this way, and look forward to how this work might be developed and expanded.

Response to Comment on "International Conservation Policy Delivers Benefits for Birds in Europe"

Rodríguez-Muñoz et al. raise concerns about our study on the effectiveness of the European Unions Birds Directive, based on the provenance of the trend data used and on the predictions that were tested. Here, we show that our results are robust to different assumptions of uncertainty surrounding trend estimates and that criticisms of the methods stem largely from misunderstandings of the original paper.

Magnitude and direction of population trends, ecological and life-history traits of 36 passerine species breeding in Europe between 2001 and 2012

Magnitude and direction of population trends (1 = 100%), ecological and life-history traits of 36 passerine species breeding in Europe between 2001 and 2012. Non-breeding niche position varies from 1 (closed forest) to 7 (open country) and non-breeding niche breadth expresses the difference between the values of the two main habitats; non-breeding habitat wetness scores from (1) dry to (3) aquatic habitats. Non-breeding regions: (1) west–central region, (2) west–east region, (3) central–south region, (4) ‘entire’ region. Breeding habitat: forest (F), wetland (W), urban (U) and open habitat (O). PC 1 expresses a gradient from ‘slower strategy’ (K-selected) species to ‘faster strategy’ (r-selected) species. PC 2 depicts a gradient from species allocating most of their energy to just one breeding attempt per season to species spreading their investments across multiple breeding attempts per season.