From desert frog to deep-sea molluscs, remarkable species at risk – IUCN Red List

The IUCN Red List now includes 175,909 species, of which 49,505 are threatened with extinction.

“Life on Earth has adapted to survive in the most hostile and unusual habitats, such as deep-sea molluscs that live around extremely hot vents or the desert rain frog burrowing into the sand. Now as pressures on biodiversity mount across the planet, even the creatures with the most ingenious survival strategies are under threat. But let us not forget there is a clear path out of the biodiversity crisis: nature conservation works, as we are reminded again and again. By protecting the astounding range of biodiversity on this planet, we can preserve a welcoming environment for humans and wildlife alike,” said Dr Grethel Aguilar, IUCN Director General.

Deep-sea mining threatens endemic molluscs

Sixty-two per cent of endemic hydrothermal vent molluscs (125 out of 201 species) known worldwide are at risk of extinction due to deep-sea mining for valuable minerals, the IUCN Red List has revealed. Found only at depths up to 5,000 metres below sea level, around vents spewing out water that can be over 450 degrees Celsius, many of these molluscs – including snails, limpets, mussels, clams and chitons – have been discovered in the past 10 years and already face extinction due to human disturbance of their habitat. Exploration of the seabed and extraction of minerals, which are in increasing demand for use in new technologies, create sediment plumes that smother the animals, impacting their ability to breathe and absorb nutrients from the surrounding water. For example, Lirapex felix – a snail named for the researchers’ luck in finding it – has today entered the Red List as Critically Endangered due to ongoing mining exploration in the Indian Ocean. Many vent species face similar threats as vents beyond national jurisdiction are explored for mining, with contracts controlled by many different countries.

The global assessment of endemic hydrothermal vent molluscs also reveals the value of protected and conserved areas, where mining is not permitted. Over 30 vent species worldwide are Least Concern thanks to living in Marine Protected Areas, such as Provanna exquisita, an ornate snail that lives only in the Mariana Arc of Fire National Wildlife Refuge in the Pacific Ocean.

“This global assessment reveals that molluscs endemic to deep-sea hydrothermal vents are one of the most highly threatened of all animal groups, at a critical moment for their future. Our new understanding of the impacts of deep-sea mining sheds light on a new frontier in science and conservation, providing important information as the International Seabed Authority meets in Jamaica this month. IUCN’s position is clear: in 2021, the Union voted for a moratorium on deep-sea mining unless all risks are understood and the marine environment is effectively protected,” said Prof Julia Sigwart, member of the IUCN SSC Mollusc Specialist Group and Head of the Marine Zoology Department at Senckenberg Nature Research, the Red List Partner that coordinated these assessments.

Conservation working for the numbat, but invasives remain a threat

The status of the numbat (Myrmecobius fasciatus) – the faunal emblem of Western Australia – has improved from Endangered to Near Threatened on the IUCN Red List. The numbat was widespread across southern Australia until the introduction and spread of cats (Felis catus) and red foxes (Vulpes vulpes), its numbers shrinking to around 300 animals by the late 1970s. Following research in the 1980s by Dr Tony Friend, member of the IUCN SSC Australasian Marsupial and Monotreme Specialist Group, and the creation of a Recovery Plan in 1994, the Western Australian Government and the Australian Wildlife Conservancy have worked to reduce the impact of feral cats and foxes through baiting and predator-proof fencing, while captive breeding at Perth Zoo and translocations have led to the establishment of at least five more self-sustaining populations. Thanks to these efforts, there are now between 2,000 and 3,000 numbats. However, the species occupies just 0.04% of its original range, and as feral cats and foxes remain a major threat, ongoing management is essential to the numbat’s survival and recovery.

Five Australian marsupials, newly recognised as a result of taxonomic review, have been confirmed as Extinct on the IUCN Red List today: the little bettong (Bettongia haoucharae) and crested-tailed, southern, northern and little mulgaras (Dasycercus cristicauda, D. archeri, D. woolleyae and D. marlowi), with no individuals reported for at least 60 years. This brings the total number of modern mammal extinctions in Australia to more than 40. Predation by feral cats and foxes is the leading cause for their decline, with climate change a growing threat to those remaining.

“Today’s assessments show that long-term, strategic and collaborative conservation effort works; without it, invasive cats and foxes will continue to drive Australia’s small marsupials and native rodents to extinction. Continued management is vital not only to maintain the numbat’s unique evolutionary line as the last surviving member of the Myrmecobiidae family, but also to support its role in maintaining a healthy ecosystem, as digging for the termites it eats increases rain penetration into the soil, helping protect woodlands,” said Prof John Woinarski, Co-Chair of the IUCN SSC Australasian Marsupial and Monotreme Specialist Group.

Diamond mining puts desert rain frog at risk of extinction

Diamond mining and energy infrastructure developments along the west coast of South Africa and Namibia have caused the desert rain frog (Breviceps macrops) to move from Near Threatened to Vulnerable on the IUCN Red List. Expanding industrial developments, which include a green hydrogen project, are expected to impact up to one-third of the desert rain frog’s range in South Africa and two-thirds in Namibia within the next 20 years. Suspected demand for the desert rain frog in the pet trade has also increased following a viral video of the species calling in distress. Climate change and associated heat stress and aridification are possible further strains on this species. Without conservation action, the population is expected to decline by 20% in the next decade.

Supporting quotes

"This IUCN update includes reassessments of 40 species of rowan, whitebeam and service trees only found in the UK and Ireland. 95% of these species remain threatened, and one species Wilmott's whitebeam (Sorbus wilmottiana), found only in the Avon Gorge, has been uplisted from Endangered to Critically Endangered because of railway works and an unknown pathogen. Reassessments are vital for monitoring changes to give us the opportunity to prevent species from going extinct," said Emily Beech, Head of Conservation Prioritisation at Botanic Gardens Conservation International.

"The new Red List findings for hydrothermal vent molluscs demonstrate why we need to protect the world’s deep and high seas. We’re still learning so much about the fragility found at the ocean’s greatest depths. Until science has more thoroughly explored the marine ecosystems at the bottom of the sea, we must be cautious of deep-sea mining and other practices that disturb the sea floor,” said Kathleen Flower, Conservation International Vice President of Biodiversity Science.

“This Red List update is the first in which we can identify flowering plants that are not only threatened with extinction but evolutionarily distinct. Evolutionarily Distinct and Globally Endangered (EDGE) species are the most unique and irreplaceable threatened species on the Tree of Life. In addition to approximately 6,000 EDGE species on the Red List, around 4,000 more are likely EDGE species, but lack global assessments. As species are assessed and confirmed to be EDGE, such as Gerritea pseudopetiolata, an Endangered Bolivian grass included for the first time in this Red List update, we are not only improving our understanding of plant extinction risk but helping to identify and prioritise the conservation of evolutionarily distinct plant diversity,” said Felix Forest, Senior Research Leader in Spatial Phylogenetics at Royal Botanic Gardens, Kew.