Extinction rates, extinction-prone habitats, and indicator groups in Britain and at larger scales

We present the first detailed comparison of extinction rates amongst a wide range of nonmarine groups, using data from Britain. For selected taxa, comparisons are made with rates in the United States and the globe. We estimate the overall extinction rate in Britain is 1–5% of the regional species list per century. Most of the groups of organisms assessed have very similar rates, with high rates in some groups which are aquatic, use dead wood or are on their climatic margin. In Britain, the extinction rate probably rose from the 19th to the 20th Century, and is projected to rise in the 21st Century. Habitat loss is the principal driver of extinctions. In Britain, birds are relatively good indicators of extinction rates and extinction-prone habitats, whilst butterflies are not. At larger scales, such as the USA and globally, birds, freshwater fish and amphibians show potential as indicators. Consideration of ‘Possibly Extinct’ species and monitoring of habitat area may provide more responsive measures of biodiversity loss.