Trying to get a picture of where and how many species globally are endangered or even at risk of extinction is a difficult undertaking. For 50 years the International Union for Conservation of Nature (IUCN) publishes the red list of threatened species. The list is a “comprehensive information source on the global conservation status of animal, fungi and plant species and their links to livelihoods”. It contains over 77,000 species of which according to the most recent report more than 22,000 are at risk of extinction. IUCN considers species at risk when they are “critically endangered, endangered or vulnerable.”
Mapped here is data from the International Union for Conservation of Nature’s (IUCN) Red List of threatened species including endangered and vulnerable species. The main cartogram shows countries resized according to all animal and plant species assessed as being at risk of local extinction. The two smaller cartograms highlight that conservation efforts have very different spatial degrees of severity, which also partly reflects the different geographical distribution of species.
Over the past decade, the islands of Mauritius and Madagascar were in various statistics frequently amongst those areas with the most species at risk living there as a proportion of all local species assessed. In absolute terms, the highest counts of species at risk are found in the countries with tropical rainforests such as Ecuador and Malaysia but also the United States with its diverse ecosystems over its large territory.
Invertebrates – estimates range between 97 and 99 per cent of all animals on Earth – are essential elements of ecosystems as waste recyclers and include insects, crabs, crayfish, corals and molluscs. By far the largest group are insects (about a million species). In the cartogram, molluscs are not included in the data while marine species at risk are assigned to the nearest territory.
In the IUCN Red List, amphibians are identified as being ‘the most threatened vertebrate group assessed […] with around 41 per cent at risk of extinction.’ Most locally threatened amphibians are observed in South America with the rainforests of Ecuador and Colombia particularly standing out from the cartogram.
For all figures presented here it is important to keep in mind that only a fraction of all known species are assessed with regards to their threat level. Many more remain unknown to mankind, some of which have become extinct in recent years without us even having realised they existed.