A new study finds deforestation could put lizards in North America at risk by 2100. Forest loss, along with climate change, is creating a lack of shelter for lizards from extreme temperatures and nearly one in five could face population decline in the next century.
The study, which was published in the journal Nature Climate Change, was led by scientists at University of Colorado Boulder and Tel Aviv University.
“Our work provides new insights into the mechanisms by which deforestation may cause population declines in the face of climate change,” Ofir Levy, a zoologist and Keith Musselman’s collaborator at Tel Aviv University, said. “The decline in lizards can lead to a cascading effect as they are an important part of almost every ecological system.”
Because “cold-blooded animals such as lizards have limited strategies to thermoregulate,” trees are an important way they maintain their body temperatures. Tree-climbing lizards move around tree trunks to bask in the sun for warmth and when it gets too hot, they climb up the trunk into the shade, according to the study’s findings.
“What’s really interesting about lizards is that they just need to be able to move a short distance around the tree trunk to get to a very different climate and habitat environment,” Musselman, an assistant professor in the Department of Geography and Colorado University Boulder’s Institute of Arctic and Alpine Research, said. “These microhabitats are particularly important when we think about how we modify our natural environment and make conservation decisions.”
The scientists “simulated lizard models for different climate regions across North America” and while “global warming can actually benefit lizards living in colder regions or at higher latitudes in North America,” without trees the lizards have less of a chance to avoid overheating.
“Here in the Rocky Mountains, elevation provides an escape for animals that can travel longer distances, including us humans,” Musselman said. “On those summer days when it hits 100 degrees, many of us will go into the mountains. But small animals like lizards can’t travel far. They heavily depend on the refuge provided by the local landscape, including tree trunks. The study highlighted the importance of understanding which elements in the environment can serve as refuges for other organisms on this planet.”
The scientists estimated that deforestation would put 18 percent of lizards in North America at risk, while a combination of forest loss and climate change could negatively impact 84 percent of the reptile.
Even though there have been international pledges to halt deforestation, forest loss continues at a rapid pace, scientists said. The study found that from 2001 to 2022, about 459 million hectares, or 12 percent, of global tree cover disappeared.
“Deforestation is a worldwide problem, and our conclusions can help decision-makers on other continents in designing conservation and habitat restoration programs that consider climate change,” Omer Zlotnick, the paper’s first author and a Ph.D. student at Tel Aviv University, said.
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