One quarter of freshwater fauna threatened with extinction

[Silurus]

Sayer, CA, E Fernando, RR Jimenez, et al. One-quarter of freshwater fauna threatened with extinction. Nature (2025). https://doi.org/10.1038/s41586-024-08375-z

Abstract

Freshwater ecosystems are highly biodiverse and important for livelihoods and economic development, but are under substantial stress. To date, comprehensive global assessments of extinction risk have not included any speciose groups primarily living in freshwaters. Consequently, data from predominantly terrestrial tetrapods are used to guide environmental policy and conservation prioritization, whereas recent proposals for target setting in freshwaters use abiotic factors. However, there is evidence that such data are insufficient to represent the needs of freshwater species and achieve biodiversity goals. Here we present the results of a multi-taxon global freshwater fauna assessment for The IUCN Red List of Threatened Species covering 23,496 decapod crustaceans, fishes and odonates, finding that one-quarter are threatened with extinction. Prevalent threats include pollution, dams and water extraction, agriculture and invasive species, with overharvesting also driving extinctions. We also examined the degree of surrogacy of both threatened tetrapods and freshwater abiotic factors (water stress and nitrogen) for threatened freshwater species. Threatened tetrapods are good surrogates when prioritizing sites to maximize rarity-weighted richness, but poorer when prioritizing based on the most range-restricted species. However, they are much better surrogates than abiotic factors, which perform worse than random. Thus, although global priority regions identified for tetrapod conservation are broadly reflective of those for freshwater faunas, given differences in key threats and habitats, meeting the needs of tetrapods cannot be assumed sufficient to conserve freshwater species at local scales.

Posted this here because this is my very first (and very likely last) paper in Nature (if you click on “show authors”, my name is buried somewhere below).

[bekateen]

Posted this here because this is my very first (and very likely last) paper in Nature (if you click on “show authors”, my name is buried somewhere below).

It doesn't matter how you got there, or how deep your name is on the list of authors. You're in Nature. Congratulations. Around my institutions, that is an honor.

That said, the news of the study is frightening although maybe not surprising.

Best,
Eric

[naturalart]

Thank you Silurus, for this.

[Crom]

Nice work on getting in to Nature

Not to echo Eric, but thank you (and your cohort) for putting the box around another aspect of the current mass extinction. Cheers. This type of research never goes out of fashion, so hoping you're not saying "last" to soon

Crom.

[Silurus]

My involvement as a coauthor was minimal (I provided very small inputs for the first draft). I guess being involved in three assessment exercises (Eastern Himalayas, Indo-Burma and Sundaland) contributed more to the paper (in terms of generating the data) than any inputs I provided for writing it.