Kivonat:

Here we develop a new method for reducing information on population trends for a large number of bird species into a simple composite indicator. This approach standardises species trends and creates a mean index across species. The headline indicator , which incorporates information on all common native species in the UK, is then disaggregated by habitat to reveal the underlying trends. The purpose of this paper is to introduce the method, discuss the most desirable qualities of wildlife indicators, to illustrate the practical difficulties in bringing such information together, and to show how the method can be used and developed.