Climate Change To Modify Geographical Distribution Of Some Reptiles, Study Says

Scientists have discovered how climate change will alter the geographical distribution of reptiles, causing the extinction of some species.

Best And Worst Scenarios For Reptiles

Reptiles that live on sandy soils in dry areas and can survive high temperatures are thought to benefit from global warming as appropriate habitats increase as a result of climate change.

However, a study by Brazilian researchers demonstrates that this is not always the case, according to a paper published in the Journal of Arid Environments.

The researchers looked at occurrence records for ten species of psammophilous squamates (five lizards and five snakes) that live in the South American Diagonal of Open Formations (DOF) or Dry Diagonal (DD), which includes Brazil's Caatinga and Cerrado biomes, as well as Argentina and Paraguay's Chaco biomes.

Experts included information about the current climate, soil types, and other environmental variables that influence these creatures' capacity to survive in their habitats.

They then simulated best- and worst-case scenarios for greenhouse gas emissions to see what these places would look like in 2040 and 2060, based on the Intergovernmental Panel on Climate Change's (IPCC) forecasts.

The models also indicated potential habitats for the species that have yet to be inspected on the ground to determine whether the animals in question reside there.

The best-case scenario for 2040, which assumes modest levels of greenhouse gas emissions, predicts that habitat loss will outweigh improvements in range and climate for all 10 species.

Micrablepharus maximiliani, a blue-tailed microtelid lizard, and Vanzosaura savanicola, a red-tailed vanzosaur, would suffer the most habitat loss. M. Maximiliani would lose 88% of its habitat, whereas V. savanicola would lose 99% and become locally extinct.

Even under the most optimistic climate change scenario, the outlook for 2060 is bleak. All ten species would experience habitat loss, ranging from 2.5 to 100%. V. savanicola, Rodriguesophis iglesiasi (Gomes' pampas snake), and Phalotris matogrossensis (Mato Grosso burrowing snake) would all become extinct. Two more lizards and a snake would suffer a 60%-82% loss.

The worst-case scenario for 2040 indicated that all species will lose more than they gained, with two losing more than 76%.

The worst-case scenario for 2060 projected significantly greater losses. Some species would make more gains than in earlier scenarios, but losses would be heavier, and V. rubricauda, another redtail vanzosaur, would become extinct.

Alarming Situation

The researchers are particularly concerned about the study's findings because this type of hazard has previously been missed for reptiles that burrow in sandy soil.

Scientists point out that the most recent nationwide assessment of endangered reptiles by the Chico Mendes Institute for Biodiversity Conservation (ICMBio), an arm of the Brazilian Ministry of Environment and Climate Change, was conducted in 2022 and did not include climate change as a risk factor, despite using the same criteria as the International Union for Conservation of Nature (IUCN).

"Some of the species for which we predict major losses and even extinction wouldn't even be endangered according to the current criteria used in this kind of threat assessment. The criteria must be changed for the next assessment," said Júlia Oliveira, first author of the article.

The study's predicted catastrophe may be avoided, or at least minimized, if new conservation units with complete protection were established and current conservation units were expanded in an optimum manner in favorable areas for these species now and in the future.