Mapping Europe’s Protection Gaps for Threatened Fungi

Europe’s celebrated network of protected areas, the backbone of the continent’s biodiversity policy, may be leaving an entire kingdom of life behind. A new study published in iScience by Ovidiu Copoț, Kadri Runnel, and Asko Lõhmus of Estonian research institutions has produced the first continental-scale assessment of how well Europe’s protected areas represent threatened fungi, and the results are sobering. Drawing on the most comprehensive distribution dataset ever assembled for these organisms, the researchers found that, on average, only 18.4 percent of the predicted habitat of 33 threatened fungal species falls within any form of protection, and strict protection covers a mere fraction of that. Only three species reached the European Union’s headline target of protecting 30 percent of land, a benchmark that the EU Biodiversity Strategy for 2030 expects all Member States to meet within this decade.

The fungal kingdom is staggeringly diverse, and its conservation status is only beginning to be understood. Of the roughly 1,300 fungal species assessed globally so far, approximately 30 percent are classified as threatened, a proportion comparable to the most imperiled groups of animals and plants. Yet transnational conservation frameworks in Europe, from the Bern Convention to the EU Birds and Habitats Directives that underpin the Natura 2000 network, explicitly target only plants, animals, and ecosystem types. Fungi appear in the national legislation of only a handful of countries, and coordinated monitoring programs remain scarce. This neglect persists despite mounting evidence that protected areas can sustain fungal diversity by preserving the specific habitat conditions, from decaying wood to nutrient-poor grasslands, on which many species depend, and that fungal hotspots only partly overlap with those of the birds, plants, and habitats that typically drive conservation prioritization.

To make fungi visible in conservation planning, the team turned to a pragmatic policy anchor: a list of 33 conspicuous threatened fungal species proposed by European mycologists for protection under the Bern Convention. The list includes fifteen mycorrhizal species that form symbiotic partnerships with tree roots, nine soil saprotrophs that decompose organic matter, and nine wood saprotrophs that inhabit dead timber. These are charismatic, readily identifiable macrofungi, including the lion’s mane mushroom Hericium erinaceus, whose predicted European habitat spans an enormous 1.78 million square kilometers, and the dune specialist Hohenbuehelia culmicola, whose habitat covers just 61,490 square kilometers. The study area encompassed all 27 EU Member States plus 11 additional European countries, covering 4.95 million square kilometers of land.

The technical core of the study lies in species distribution modeling. Because fungal occurrence records are fragmented, unevenly available across countries, and heavily biased toward well-surveyed regions, the researchers compiled and harmonized evidence from public biodiversity databases, including GBIF, MycoPortal, iNaturalist, GlobalFungi, and national databases, together with published environmental DNA datasets. In total, 16,009 cleaned occurrence records, ranging from 20 to 2,325 per species, were thinned to one record per square kilometer. For each species, the team built two complementary MaxEnt models: a bioclimatic model using nineteen WorldClim variables plus potential evapotranspiration, and a landscape model incorporating land cover, tree host distributions, soil properties such as pH and organic carbon, and human-impact variables including nitrogen deposition and the human footprint. Collinearity among predictors was handled through principal component analysis, and model performance was strong, with average AUC values of 0.934 for bioclimatic and 0.880 for landscape predictions.

The resulting habitat maps revealed striking biogeographic patterns. Co-occurrence of target species, evaluated at one-square-kilometer resolution, peaked in the boreal forests of Fennoscandia and the Baltic countries, where at least ten species were predicted to co-occur across roughly half of the landscape. Alpine and southern continental regions followed, while co-occurrence was rare in the Mediterranean and Pannonian regions despite many species having predicted habitat there. The steppe, Arctic, and Black Sea bioregions held the least fungal habitat overall. On average, 47 percent of each species’ predicted habitat was classified as genuinely suitable, with the remainder only marginally suitable, but soil-saprotrophic species fared far worse, with just 23 percent of their habitat deemed suitable, suggesting that high-quality habitats for this ecological group are exceptionally scarce across the continent.

Overlaying these predictions with protected area boundaries exposed the gap. IUCN-classified protected areas cover 13.65 percent of European land, of which only 3.17 percent is strictly protected, while Natura 2000 sites outside formal protected areas add a further 8.62 percent. For the 33 fungi, overall habitat protection averaged 18.4 percent, and nearly half of that was provided by Natura 2000 designations whose regimes, as broad-scale evidence shows, often fall short of core conservation objectives. Without counting Natura areas, mean protection dropped to 12.7 percent, and for the charcoal soma Sarcosoma globosum it was just 3 percent. Strict protection of suitable habitat was even scarcer, ranging from under 0.5 percent of predicted habitat in fifteen species to a maximum of 5.9 percent in the bracket fungus Anthoporia albobrunnea. Soil saprotrophs again fared worst, with strict protection covering roughly 0.4 percent of their habitat.

The study then asked a question with profound policy implications: how should the remaining protection burden be shared among countries? Under a hypothetical country-by-country approach, in which each nation independently protects a minimum threshold of habitat for every species present within its borders, the required additional protection exceeded 30 percent of existing habitat for 27 species, and combined with current protection would bring total coverage to between 39 and 71 percent of predicted habitat. The burden also fell disproportionately on a few forest-rich countries: Sweden received the largest extension requirement for sixteen species, Finland for two, and Norway ranked third for sixteen. This concentration reflects centuries of divergent land-use history, since countries that industrialized agriculture earliest have lost most of their natural habitat, and it raises fundamental questions of international environmental justice about who should bear the costs of protecting what remains.

Because such a country-by-country approach proved clearly suboptimal, the authors outline three regionally coordinated alternatives. First, countries could prioritize species for which they hold a large share of global habitat, such as the Fennoscandian endemism of Haploporus odorus, whose entire predicted range lies within that region. Second, where restricted-range species are absent, countries could target large multi-species gaps at hotspot sites; Slovakia, for example, hosts protection gaps exceeding 1,000 square kilometers for seventeen species, so filling them would relieve pressure elsewhere. Third, above minimum thresholds, countries could contribute proportionally to continental targets based on their share of each species’ habitat. The analysis also identified restoration responsibilities for 24 species, concentrated in relatively few countries, and showed that existing Natura 2000 areas could account for just over a fifth of the summed protection gaps in the EU, and more than a third of the gap for six particular species.

The broader message is unambiguous: biodiversity loss in Europe cannot be effectively addressed using established plant, animal, and habitat-type targets alone. Fungal habitats have not been systematically incorporated into the continent’s protected-area networks, and future expansion strategies risk reinforcing existing taxonomic biases unless neglected groups are explicitly prioritized. The study acknowledges limitations, including model uncertainty that grows with fewer occurrence records, overprediction in poorly surveyed countries such as Romania, Bulgaria, and Albania, and the fact that habitat representation does not by itself guarantee population persistence. Yet the authors argue that predicted habitat maps could immediately inform management within existing protected areas, guide field surveys and eDNA sampling to verify populations, and serve as evidence when comparing candidate areas for protection or restoration under the EU Biodiversity Strategy. With the 2030 deadline approaching, the invisible kingdom of fungi may finally be gaining a seat at the conservation planning table, provided Europe’s governments choose to coordinate rather than calculate alone.

Subject of Research: Gap analysis of European protected area coverage for threatened fungi using species distribution models

Article Title: Where to improve the European protected areas network to represent threatened fungi?

Article References: Copoț, O., Runnel, K., & Lõhmus, A. (2026). Where to improve the European protected areas network to represent threatened fungi?. iScience, 29(11), Article 117758. https://doi.org/10.1016/j.isci.2026.117758

Image Credits: AI Generated

DOI: 10.1016/j.isci.2026.117758

Keywords: fungi conservation, protected areas, Natura 2000, species distribution models, Bern Convention, EU Biodiversity Strategy, mycorrhizal fungi, habitat restoration, biodiversity gap analysis, MaxEnt, Europe, eDNA