Making the most of birds as environmental indicators

Never previously has there been such an opportunity for biologists to inform and advise environmental decision-makers. Ornithologists have a special contribution to make because of the extent and quality of the information available to us. This paper focuses on environmental indicators - the process by which complex information about the environment can be encapsulated in some simply understood measures. This paper reviews the properties of effective indicators and the contribution that ornithology can currently make. Attention is given to globally threatened species, common bird monitoring schemes, summarising trend data from many species and to spatial questions about the distribution of biodiversity.