April 15, 2026

One in Five Assessed Soil Species at Risk of Extinction, Data Needed for Thousands More - Study

  • New research finds that one in five assessed soil‑dependent species is threatened with extinction on The IUCN Red List of Threatened Species™.
  • More data on the majority of soil‑dependent species is needed to determine their extinction risk.
  • Researchers call for more soil-dependent species to be assessed on the IUCN Red List.

ARLINGTON, Va. (April 15, 2026) – A new report led by Conservation International and IUCN, published today in Oryx, warns that over 40% of more than 8,500 soil‑dependent species are at risk of extinction or Data‑Deficient on The IUCN Red List of Threatened Species™.

Soil is central to human survival. Ninety-five percentNinety-five percentof the food humans consume depends on it, and healthy soil could store up to 27% of the carbon needed to keep global warming below two degrees Celsius. Yet despite its importance, many of the species that keep soil healthy are now at risk.

“Soil sustains many of the most essential parts of human life, yet we still have not sufficiently studied the thousands of species within it” said Neil Cox, Manager of the Biodiversity Assessment Unit, a joint initiative of Conservation International and IUCN. “This study draws attention to the dire state of many soil‑dependent species, and we hope its publication spurs the increased focus and funding needed to understand how to conserve these species.”

Key findings:

  • This study highlights the troubling reality that 20% of assessed soil species (at least 1,758 species) are at risk of extinction, according to the IUCN Red List
  • The study also found that we lack sufficient data to determine the status of another 20% (1,722) of these assessed species
  • Soil is home to about 59% of Earth’s species, yet there remains a major gap between the importance of these thousands of soil‑dependent organisms and what we know about them
  • Soil biodiversity is underrepresented on the IUCN Red List of Threatened Species, the most comprehensive information source concerning the global extinction risk of species

The knowledge gap around soil biodiversity poses a threat to one of Earth’s most vital resources. To urgently address it, the study recommends:

  • The establishment of an IUCN SSC Soil Biota Working Group to elevate and coordinate action on soil biodiversity
  • That ties be strengthened between regional and global organizations working on soil biodiversity management
  • More effective knowledge-sharing between IUCN, governments, landholders, and the public on the importance of soil conservation

Without these species, we risk further degradation of the earth’s soil, which is vital to global agricultural production. Soil health underpins food systems worldwide, and the threat of soil degradation must be taken seriously for the sake of people, animals and the planet as a whole.

“The IUCN Red List is a vital tool for understanding the health of global biodiversity, yet most soil species remain understudied or unlisted,” said Dr. Gregory Mueller, author on the paper and Chair of the IUCN SSC Fungal Conservation Committee, whose members contributed to the paper. “Soil species shape so many parts of life on this planet – for example, fungi enable plants to take in nutrients and make decomposition possible, underpinning ecosystems. It is crucial that we give all soil species the attention they deserve and work to better understand and protect them.”

“Invertebrates are critical to soil health, with their roles in nutrient cycling and improving soil structure. With healthy biodiversity at the foundation of our agricultural systems, building systems to conserve these species is essential for food security,” said Dr. Axel Hochkirch, Co-Chair of the IUCN SSC Invertebrate Conservation Committee.

For more about Conservation International’s work on soil conservation:

Learn more about IUCN’s work on adding soil species to the IUCN Red List and its Conserving Healthy Soils Issues Brief.

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About Conservation International: Conservation International protects nature for the benefit of humanity. Through science, policy, fieldwork and finance, we spotlight and secure the most important places in nature for the climate, for biodiversity and for people. With offices in 30 countries and projects in more than 100 countries, Conservation International partners with governments, companies, civil society, Indigenous peoples and local communities to help people and nature thrive together. Go to Conservation.org for more, and follow our work on Conservation News, Facebook, Twitter, TikTok, Instagram and YouTube.

About The IUCN Red List of Threatened Species™: The IUCN Red List of Threatened Species™ (or The IUCN Red List) is an invaluable resource to guide conservation action and policy decisions. It is a health check for our planet – a Barometer of Life. It is the world’s most comprehensive information source on the global conservation status of animal, fungus and plant species. It is based on an objective system for assessing the risk of extinction of a species should no conservation action be taken.

Species are assigned to one of eight categories of threat based on whether they meet criteria linked to population trend, population size and structure and geographic range. Species listed as Critically Endangered, Endangered or Vulnerable are collectively described as ‘threatened’.

The IUCN Red List is not just a register of names and associated threat categories. It is a rich compendium of information on the threats to the species, their ecological requirements, where they live, and information on conservation actions that can be used to reduce or prevent extinctions. When an animal, fungus or plant changes Red List Category for genuine reasons, this reflects a change in the extinction risk for that species. It is therefore a key indicator for tracking conservation successes and failures. The IUCN Red List is a joint effort between IUCN and its Species Survival Commission, working with its IUCN Red List partners – ABQ BioPark; Arizona State University; BirdLife International; Botanic Gardens Conservation International; Conservation International; Missouri Botanical Garden; NatureServe; Re:wild; Royal Botanic Gardens, Kew; Sapienza University of Rome; Senckenberg Society for Nature Research; Texas A&M University; and Zoological Society of London. This work has been made possible with the essential contribution of the Red List Partners. www.iucnredlist.org, Facebook, X.

About IUCN: IUCN is a membership Union composed of both government and civil society organisations. It harnesses the experience, resources and reach of its more than 1,400 Member organisations and the input of more than 17,000 experts. IUCN is the global authority on the status of the natural world and the measures needed to safeguard it. www.iucn.org, Facebook, Instagram, LinkedIn, X, TikTok

About the Species Survival Commission (SSC): With over 11,000 members in 186 countries, the Species Survival Commission (SSC) is the largest of the seven expert commissions of IUCN and enables IUCN to influence, encourage and assist societies to conserve biodiversity by building knowledge on the status and threats to species, providing advice, developing policies and guidelines, facilitating conservation planning, and catalysing conservation action. The SSC has been recognised as “the world’s largest volunteer conservation-science network” by Guinness World Records ®. Learn more at www.iucn.org/ssc.