Many conifer species are on the road to extinction from climate change

Many conifer species are on the road to extinction from climate change. A new study led by Brown University has revealed that many conifer species will be threatened with extinction by 2070 as a result of climate change. The research was focused on 55 conifer groups, including fir and pine trees. 

Based on global warming predictions from the Intergovernmental Panel on Climate Change (IPCC), up to a quarter of the tree species examined for the study will face extinction in a matter of decades. The groups that are the most at risk are native to small islands.

“Our work shows that species native to relatively small islands are in a lot of danger from climate change, and relatively soon,” said study co-author Professor Dov Sax. “But the work also helps us to identify which species are most at risk and which are least at risk, which helps to prioritize conservation.”

While traditional risk assessments have assumed that trees can only withstand the climate extremes of their native habitats, the current investigation took a new approach by pursuing a more realistic estimate of the climate conditions that a certain tree species can handle.

“If you just look at conditions in native ranges and you model risk off of that, you’d conclude that everything on small islands is doomed,” said Profeessor Sax. “But we know that many of these species have survived past instances of climate change, so what we wanted to do here was think about what conditions species could potentially thrive in if they needed to.”

The researchers used data on where members of a given species are known to survive beyond their native ranges and categorized the groups into three categories of climate niches. Next, the researchers used IPCC estimates of future warming to see which were in danger. Under the IPCC’s most extreme climate scenario, 23.6 percent of the species will be pushed outside of their fundamental niches.

“At first, we were encouraged to discover that most species show a lot of wiggle room in their climatic niches,” said study co-author Kyle Rosenblad. “But alarmingly, all this wiggle room still isn’t enough to buffer some of them from predicted changes in climate.”

On one end of the spectrum, the Canary Island Pine is expected to stay within its fundamental niche and will not be threatened with extinction. To the opposite extreme is the Bermuda Cedar, which is expected to be pushed out of its fundamental niche and even out of its tolerance niche. In other words, there will be no place on its native island where the Bermuda Cedar will be able to survive. 

“We found a whole range of range of species that will look like they’re fine,” said Professor Sax. “They’ll be alive and you may even see some seedlings. But since they can’t reproduce sufficiently to maintain their population on their own, they’ll actually be on the road to extinction.”

The study is published in the journal Nature Climate Change.

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By Chrissy Sexton, Earth.com Staff Writer