Aggregated biodiversity indicators are indices that combine data on many species or habitats into a single parameter to describe average changes in status or trends of species or habitats
Examples of aggregated indices are the Living Planet index (LPI), red list indices, and aggregated long-term data for particular taxonomic groups, such as Wild Bird Index (WBI).
The Living Planet Index (LPI) is an indicator of the state of global biodiversity based on trends in populations of species from around the world. The LPI is calculated using time series population data for vertebrate species. It is updated and published biannually in the WWF Living Planet Report. The 2006 LPI is based on over 3,600 populations for over 1,300 species of fish, amphibians, reptiles, birds, and mammals.
The Wild Bird Index (WBI) measures average population trends of a representative suite of wild birds. It acts as an indicator of the general health of the wider environment, based on the assumption that declines in wild bird populations are intrinsically linked to the degradation of their environment. The indicator can be applied to different geographic scales and different habitats, and is already used widely across Europe to measure aspects of sustainable human development. The WBI is currently being extended to the global scale. A related index is the Farmland Bird Index.
The Red List Index summaries information on the conservation status of species or habitats. It thus provides integrated information on changes in the degree of threatenedness of species or habitats. Information on its calculation can be found in: Butchart, S.H.M., Akçakaya, H.R., Chanson, J., Baillie, J.E.M., Collen, B., Quader, S., Turner, W.R., Amin, R., Stuart, S.N., Hilton-Taylor, C. 2007. Improvements to the Red List Index. PLoS ONE 2(1): e140.