Palo de Cruz is classified as Least Concern, according to the IUCN Red List assessment. Photo: 3t Vakil
Thirty-eight percent—or more than 1 in 3—of the world’s trees are at risk of extinction according to the first Global Tree Assessment, published Monday by the International Union for Conservation of Nature (IUCN).
For the first time, the majority of the world’s trees have been listed on the IUCN Red List, the world’s most comprehensive information source on global extinction risk status. According to the list, at least 16,425 of the 47,282 tree species assessed are at risk of extinction. Trees now account for over one quarter of species on the IUCN Red List, and the number of threatened trees is more than double the number of all threatened birds, mammals, reptiles and amphibians combined. Tree species are at risk of extinction in 192 countries around the world.
With these additions, the IUCN Red List now includes 166,061 species of all kinds—of which 46,337 are threatened with extinction.
“Trees directly underpin the survival of so many species, including many found on the IUCN Red List. Thriving, naturally diverse forests are essential in mitigating both climate change and biodiversity loss, and as such solutions for one crisis often have mutually reinforcing benefits for the other. This makes the growing number of threatened tree species included on the Red List all the more troubling,” said Dr. Dave Hole, Vice President for Global Solutions at Conservation International’s Moore Center for Science.
The Global Tree Assessment relied on a global network of over 100 institutional partners and more than 1,000 experts to generate the dataset over many years.
According to the report, island trees are the most threatened due to deforestation to urban development and agriculture, as well as invasive species, pests and diseases. In the tropics, climate change-induced sea-level rise and stronger, more frequent storms also increasingly threaten trees.
“Trees are seen as an easy fix to climate change and trees are planted everywhere; but the way reforestation is done needs to be greatly improved, diversifying species and including threatened ones in tree-planting schemes. Governments and their forestry departments, companies and all those planting trees could easily do this and get positive impact quickly, tackling both the climate change and biodiversity crises,” said Jean-Christophe Vié, Director General of Fondation Franklinia, which funded most of the Global Tree Assessment.
Meanwhile, in South America, 3,356 out of 13,668 assessed species are at risk of extinction due mostly to forest clearance for crop farming and livestock ranching. This comes from the continent that is home to the greatest diversity of trees in the world.
Of course, it’s not just trees at risk. Over two-thirds of globally threatened bird species are dependent on forests; not to mention the thousands of plants, fungi and other animals that rely on trees for food, protection, and overall survival. Humans also depend on trees, with over 5,000 of the tree species on the IUCN Red List used for timber in construction, and over 2,000 species used for medicines, food and fuels respectively.
“The significance of the Global Tree Assessment cannot be overstated, given the importance of trees to ecosystems and people. We hope this frightening statistic of 1 in 3 trees facing extinction will incentivize urgent action and be used to inform conservation plans,” said Dr Eimear Nic Lughadha, Senior Research Leader in Conservation Assessment and Analysis at the Royal Botanic Gardens, Kew.
Vié agrees, joining the other expert authors in suggesting innovative approaches like seed banks and botanic garden collections, as well as the establishment of “Key Biodiversity Areas” and enhanced spatial planning.
“We now know where to act to efficiently tackle the extinction crisis hitting the world’s trees. There is no excuse not to,” said Vié.