Around two million species are endangered worldwide, twice as many as assumed in the latest global inventory by the World Biodiversity Council (IPBES) in 2019. This is the conclusion of an international study published in the journal PLOS One. According to the study, a fifth of all animal and plant species examined in Europe are threatened with extinction in the coming decades, with plants and invertebrates being particularly affected.
The researchers included all 14,669 animal and plant species in the study that were on the Red List for Europe at the end of 2020. This corresponds to 10 percent of the continent’s species. The World Conservation Union (IUCN) lists species whose populations have been analyzed. Many are not endangered or only slightly endangered, but others are threatened with extinction or are already extinct. The species analyzed include vertebrate species (amphibians, birds, fish, reptiles, and mammals), invertebrate groups such as butterflies and bees, and various plant species.
Invertebrates Particularly Affected
Axel Hochkirch, the lead author, from the National Museum of Natural History in Luxembourg and the University of Trier came to the conclusion that 2839 of the 14,669 species studied—roughly 19 percent—are in danger of extinction in Europe. 125 animal and plant species are already considered extinct, regionally extinct, or possibly extinct.
According to the study, around 27 percent of the plants native to Europe are threatened with extinction. The figures are also high for animal species: 24 percent of invertebrates and 18 percent of vertebrates are affected. This pattern is remarkable, according to the research team, considering that much more attention is paid to vertebrates. “One of the most important findings is that the number of endangered species does not differ significantly across the various species groups,” says Hochkirch.
Other experts consider the current data to be relevant and credible. Matthias Glaubrecht from the University of Hamburg explains: “The new study shows much more clearly and comprehensively than before that significantly more species are threatened with extinction. Europe is one of the regions for which we still have the best data. If the situation here is already so dramatic, this means that the biodiversity crisis in other, far more species-rich regions is very likely to be even more explosive, especially in the tropical regions that are still insufficiently researched, such as Asia and Africa.”
Using new data sets, the team also calculated the number of animal, plant, and fungal species threatened with extinction worldwide: at two million, the number is twice as high as in the most recent IPBES report from 2019, when IPBES came to the conclusion that one million of the estimated eight million species were threatened. The doubling to two million threatened species within a few years can be explained by new and more precise information, explains Josef Settele, co-author of the last IPBES report: “The studies ultimately build on each other and thus also reflect the progress of knowledge. The 2019 IPBES report also mentioned a data gap, which we are now getting closer to closing.”
The data situation remains a problem; the study authors write: “Our analysis reveals some major gaps in knowledge and a corresponding need for research.” Many species, especially among the invertebrates, have not even been described yet. It is often difficult to accurately assess their status; if there are only a very few specimens left in a region, they are almost impossible to find in field studies. Glaubrecht also confirms this: “We know too little about all these species to have noticed their disappearance for a long time. There are species that we are destroying faster than we can study them.”
The causes of species extinctions are manifold. The team believes that the greatest threat is the intensive economic use of land and oceans, which leads to the loss of habitats. The overexploitation of biological resources and extreme weather conditions caused by climate change also pose a massive threat to biodiversity.
However, the researchers also see reason for hope: the resettlement of animal species and special protection can help preserve biodiversity. “It is important to implement the necessary conservation measures in good time,” said Hochkirch. “We already have enough evidence to act; what we lack is action.”