The number of fish species at risk of extinction could be fivefold higher than previously estimated, with nearly 5,000 species not receiving a conservation status due to insufficient data.
That’s according to a peer-reviewed study published in the journal PLOS Biology on Thursday, and led by scientists from the Marine Biodiversity, Exploitation, and Conservation Unit in Montpellier, France.
By leveraging machine learning algorithms, the authors found that the extinction risk for marine fish species stands at 12.7%, up from the International Union for Conservation of Nature’s (IUCN) estimate of 2.5%.
“While extinction risk categorisation is fundamental for building robust conservation planning for marine fish, empirical data on occurrence and vulnerability to disturbances are still lacking for most marine teleost fish species, preventing the assessment of their IUCN status,” the study says.
To bridge this knowledge gap, scientists trained the algorithms to predict the extinction risk of 13,195 marine fish species selected from the Ocean Biodiversity Information System database, a global open-access data and information platform.
Out of these, 4,992 were not assessed by IUCN. Researchers categorised 1,337 of them as threatened species – including the Cryptobenthic fish, considered crucial to reef ecosystems – which may be undergoing a “silent extinction process”.
Another 2,582 species were classified as non-threatened, while approximately 1,000 remained unassessed.
“Artificial intelligence enables the reliable assessment of extinction risks for species that have not yet been evaluated by the IUCN,” said co-author Nicolas Loiseau, urging the IUCN to incorporate advancements in forecasting species extinction risks into their approach.
IMPACT ON CONSERVATION
According to the study, the underestimation of extinction risks among fish species is leading to inadequate conservation strategies, undermining efforts to meet the Global Biodiversity Framework’s target of protecting 30% of seas by 2030.
Scientists stressed that a more extensive and accurate IUCN classification of marine fish species could reevaluate the prioritisation of new marine protected areas, with the South China Sea, the Philippine and Celebes Seas, and the west coasts of Australia and North America emerging as critical hotspots.
The IUCN Red List of Threatened Species is the world’s most comprehensive source on the global extinction risk status of animal, fungus, and plant species.
The new study is based on the over 150,000 species listed last year, though the Red List now includes more than 160,000 species, as announced in June.
However, according to the study, the annual update of the IUCN Red List “brings to the public biased information on the state of biodiversity with a much greater emphasis on few taxa, such as vertebrates”.
“It is now essential to develop a pragmatic approach to extend extinction risk assessments towards overlooked taxa … combining large-scale data sets into a multi-machine learning framework.”
Last year, a group of researchers warned against overreliance on IUCN’s Red List of Threatened Species in conservation policies, as the assessed number of species is still far from reflecting the total number of the properly described global species, estimated up to 2 million.
By Giada Ferraglioni – giada@carbon-pulse.com
* Click here to sign up to our twice-weekly biodiversity newsletter *
