As summer temperatures soar, humans and animals alike seek refuge from the sweltering heat. For many small creatures like lizards, forests provide a critical sanctuary, offering shade and cooler microclimates. However, a concerning new study reveals that the combined effects of climate change and deforestation could devastate lizard populations across North America.
The research, published in the journal Nature Climate Change on March 5th, was conducted by scientists from the University of Colorado Boulder and Tel Aviv University. Their findings indicate that by the end of this century, a staggering 84% of North American lizard species could be negatively impacted, with nearly one in five facing potential population decline.
Unlike mammals that can regulate their body temperature through sweating or insulation, cold-blooded lizards have limited thermoregulation strategies. Tree-dwelling lizards rely on moving around tree trunks to bask in the sun for warmth or seek shade when the ground becomes too hot.
“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,” said Keith Musselman, an assistant professor at CU Boulder. “These microhabitats are particularly important when we think about how we modify our natural environment and make conservation decisions.”
While global warming may benefit lizards in cooler regions by increasing their activity time, the team’s computer simulations revealed that deforestation would largely negate these positive effects. Tree loss could decrease lizards’ activity time by an average of 34% by 2100, forcing them to seek shelter under rocks or in caves to avoid overheating.
“Our work provides new insights into the mechanisms by which deforestation may cause population declines in the face of climate change,” said Ofir Levy, a zoologist collaborating with Musselman at Tel Aviv University. “The decline in lizards can lead to a cascading effect as they are an important part of almost every ecological system.”
Despite international pledges to halt deforestation, tree clearing continues globally. From 2001 to 2022, about 12% of global tree cover disappeared, exacerbating the threat to lizards already struggling to adapt to a rapidly warming planet.
“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,” said Omer Zlotnick, the paper’s first author and a Ph.D. student at Tel Aviv University.
As Musselman explained, “Here in the Rocky Mountains, elevation provides an escape for animals that can travel longer distances, including us humans. 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 underscores the importance of understanding how different elements of the environment can serve as refuges for Earth’s most vulnerable organisms in the face of climate change and habitat loss.
#Biodiversity #ConservationBiology #ClimateChange #Deforestation
