Climate change could cause 'generational trauma' in great apes
Some of Africa's great apes - humanity's closest cous‐ ins - face death and disrup‐ tion as the planet warms, according to new research.
The findings, published today in the academic jour‐ nal PLOS Climate, suggest cli‐ mate change will create dan‐ gerous conditions in hun‐ dreds of ape habitats across the continent.
"They're facing a lot of threats that are much more imminent than climate change," said Stefanie Heinicke, a postdoctoral re‐ searcher at the Potsdam In‐ stitute for Climate Impact Re‐ search in Germany.
"But this will add an addi‐ tional stressor - and in some habitats, it already has."
Heinicke, alongside
African climate researchers, looked at 333 sites where African apes live, finding that all of them had experienced temperature increases. Using projections of a world warmed to both 2 C and 3 C above pre-industrial levels, the team found these habi‐ tats would also see more ex‐ treme impacts.
Heinicke's research points to more days where heavy rainfall would hit these habi‐ tats. As she explained to CBC News from Potsdam, there would also be an increased number "of consecutive dry days, so days where repeat‐ edly you don't have any rain‐ fall."
Feeling it across genera‐ tions
The research also found that some of these ape popu‐ lations would be more ex‐ posed to extreme climate events like wildfires, drought, cyclones and heat waves events that have the potenti‐ al to not only reduce food se‐ curity but physically break up groups, as seen during flood‐ ing from intense rainfall.
"When you have really large groups, it potentially cuts off individuals from oth‐ er individuals that they might know," explained Ammie Kalan, a primatologist at the University of Victoria. She says this isolation breaks down the social networks of these apes, and that the longer these extreme climate events last, the worse the damage to the animals.
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"It suggests generational trauma that's going to happen to these ape popula‐ tions," Kalan told CBC News. She said the deaths of older members can affect the en‐ tire group's resilience.
"If you cut out whole gen‐ erations, you lose these knowledgeable individuals that have the potential to provide that kind of safety net that can help out those younger individuals."
Indirect pressure
The greatest threat to ape populations in Africa is habitat loss, and the pres‐ sure of one extreme climate impact - crop failure - could feed into that.
The Intergovernmental Panel on Climate Change's latest report says global warming will drive up heat waves and drought in Africa and is already reducing crop yields and productivity.
"What you see, as a result of humans then trying to sur‐ vive in these desperate cir‐ cumstances, is that they turn to the forest for resources," Kalan said, describing it as a source of food and fuel such as charcoal.
For Rachel Ashegbofe Ike‐ meh, founder-director of the South-West/Niger Delta For‐ est Project, climate change can make a human-caused situation worse.
"When you talk about wildfires," Ikemeh said, "we've seen a lot of that around or near my project site in Ise Ekiti - where we are preserving the last strong‐ hold of chimpanzee popula‐ tions in southwestern Niger‐ ia."
Ikemeh, who has been in conservation for almost 20 years, gave an example of wildfires started during the dry season by farmers clear‐ ing their land.
"But what spreads wild‐ fires in these environments is the heat conditions," she told CBC News from Durban, South Africa.
"When it's dry, it makes [it possible for] a small fire that a farmer sets in his small farm to spread to several hundreds of acres of land."
A 1-degree difference Heinicke says that be‐ cause the primary threats to apes are deforestation and hunting, there hasn't been a strong climate change argu‐ ment made in conservation efforts. But there's value, say experts, in showing how both 2 C and 3 C differences would affect ape popula‐ tions.
"These general projec‐ tions can help to basically support why mitigation ef‐ forts need to happen," Kalan said, adding that the 2 C sce‐ nario will be less severe on great apes.
Bella Lam, CEO of the Jane Goodall Institute of Canada, says any solutions need to consider what's pushing communities to encroach on ape habitats.
"You cannot protect chim‐ panzees without looking at ... the same drivers impacting poverty, impacting food inse‐ curity, gender equality," Lam said. "All these things that im‐ pact the development of the communities sharing, really, the same ecological space."