We live in a time of never-ending bad news when it comes to our natural world. The latest involves amphibians like frogs, toads, and salamanders. A new study out Monday offers further evidence of how imperiled the world’s 8,000 or so known species are. In fact, around 50 percent of them may be threatened with extinction, per the new study, not the 40 percent that’s the current official estimate.
The paper, published in the journal Current Biology, has a simple premise: There’s not much data on more than half of these species. That’s partially due to the fact that new species are still being discovered. Assessing them and determining their conservation status takes time. So, the team of researchers from Yale University and the University of Sheffield looked at the data that does exist and popped it into some models.
As it turns out, another 1,012 amphibian species may be facing extinction. That’s on top of the roughly 2,000 the International Union for Conservation of Nature and Natural Resources has already flagged. Nearly half of these 1,012 species are probably endangered or critically endangered, and three may already be extinct.
The study doesn’t go deep on specific causes, but it does shout out habitat loss, “the largest threat for amphibians.” The chytrid fungus humans have been spreading around the world is another culprit, as a study out earlier this year found. The fungal disease has been on the move the last 20 years, and amphibians that have been exposed haven’t been faring so well.
To assess extinction risk for amphibians lacking up to date data, the authors looked at a few factors: the threat status for species that have been previously assessed, their evolutionary connection to un-assessed species, the known traits of all amphibian species, their range sizes, and global land cover to examine human activity near their habitats. A species’ body size and range size most correlated with how threatened it is, the study found. Human encroachment also mattered a lot.
“Urgent conservation actions are needed to avert the loss of these species,” said study author Pamela González-del-Pliego, a researcher at both the University of Sheffield and Yale University, in a statement.
However, not all hope is lost. This assessment also found that some threatened species—whether directly assessed or predicted to be threatened by this study—see geographical overlap. This is the case in the Neotropics, including Central America and South America—and this region sees the largest number of threatened species. That could make them easier to save, as efforts to conserve some of the assessed species should positively affect those that haven’t been properly assessed.
A proper assessment is key, though. This study is based on only models. It’s essentially a scientifically informed guess. For all we know, the situation could be worse. Or, perhaps, the situation is a bit better. A little hope ain’t ever hurt nobody.