
The International Union for Conservation of Nature and Natural Resources (IUCN) has regularly published its Red List of Threatened Species since 1964. The Red List also indicates the general state of biodiversity, which is why it is a valuable source of information not only for conservation organisations. The Red List divides animal and plant species into nine categories, from ‘not evaluated’ to ‘extinct’. ‘Vulnerable’ and ‘endangered’ are the most relevant categories, as they most clearly demonstrate the threat level. Both categories have continued to expand recently.