In a similar vein to ARKive and NBN Gateway, the WWF has launched a service called Wildfinder – a whopping great database of the geographic distribution of all known birds, mammals, reptiles and amphibians.
The database can be searched by species (common or scientific name) or location, and it’s the location searching that makes this site interesting. You can look in detail at one of 825 ecoregions (areas with specific ecological characteristics) or enter a place name to bring up the ecoregions nearby. Birmingham, my current corner of the world, is classified as PA0409 – Celtic broadleaf forests and PA0421 – English Lowlands beech forests, meaning there should be 257 species in the area. Perhaps unsurprisingly, none are endemic.
One incredibly useful function would be the ability to see how biodiversity and species distribution change over time – with a decade’s worth of monthly snapshots, trends of migration and decline could be built up relatively easily.