A first list of endangered mushrooms in France

For the first time, the Red List of Threatened Species in France has focused on mushrooms, exploring the situation of boletes, milkcaps and tricholoma. Of the 319 species listed in these three groups in mainland France, 12 species are threatened, such as the ruby bolete, the reticulated willow milkwort and the oak bolete, while 16 others appear to be near-threatened.

These results are the fruit of analyses coordinated by the French Committee of the International Union for Conservation of Nature (IUCN), the French Biodiversity Agency (OFB) and the National Museum of Natural History (MNHN), with the knowledge and expertise of numerous mycologists and in collaboration with the Association for the development of naturalistic and IT tools for Fungi (AdoniF).

Belonging to the category of cap mushrooms, boletes, milkcaps and tricholoma are found mainly in forests and occasionally in open environments, from coastal plains to high mountains. They are composed of a filamentous underground part, the mycelium, and an outer part, supporting the cap, which contains the spores that enable them to reproduce. Many of them live in symbiosis with trees, which provide them with sugars from photosynthesis and receive water and nutrients in return.

To identify pressures and guide conservation priorities, the risk of extinction of each of these species has been assessed. Among the threatened species, the Mountain Milkcap (Lactarius salicis-reticulatae) is considered “Critically Endangered”, the Brawny Bolete (Imperator torosus), the Ruby Bolete (Chalciporus rubinus) and the Boreal Yellow Milkcap (Lactarius tuomikoskii) are classified as “Endangered”, and the Red-pored Bolete (Rubroboletus pulchrotinctus), while the Lactarius pilatii (a bog Milkcap) and the Yellow Knight (Tricholoma equestre) are classified as “Vulnerable”.

Threatened habitats and the pressure of climate change

The main threats to these species are the destruction and degradation of their natural habitats, including intensive forestry with the felling of old trees and clear-cutting, the conversion of certain forests to farmland, as well as urbanization and tourist developments in the mountains. Climate change represents another major threat, drying out the habitats of species favoring cool and wet environments in particular, and increasing the frequency of storms, droughts and fires for forest-dwelling species. Other pressures, such as wetlands draining and backfilling, spreading fertilizers and fungicides, and intensive grazing, also affect these species.

A quarter of species assessed still poorly known

In terms of knowledge, the report reveals a lack of information for 25% of the fungi assessed, which are classified as “Data deficient”. This is particularly the case for the Birch Milkcap (Lactarius tabidus) and the Corsican Boletus (Leccinellum corsicum). This situation encourages the development of field surveys and the improvement of available information, because although only 3.8% of mushrooms currently appears to be threatened, this percentage should increase once knowledge has progressed to specify their conservation status.

The Red List is essential to better understand and protect mushrooms

Despite the threats to their natural habitats, no mushroom species is currently the subject of a dedicated conservation program or specific protection measures. The results of the Red List will help guide knowledge acquisition strategies and priorities for action. In particular, the report highlights the importance of combating climate change and preserving natural environments, especially forests, to safeguard species diversity and our territory’s mycological heritage.