Bushmeat hunting, or the hunting of meat from wild animals, may be transforming the rain forests in Africa.
When hunters kill gorillas and other primates for their meat, the primates no longer disperse the seeds of some fruit- and nut-bearing trees, and wind-dispersed seedlings take root instead, according to a study published today (March 19) in the journal Proceedings of the Royal Society B.
"The seedling communities of the forest floors are really different in a hunted forest compared to a well-protected forest," said study co-author Ola Olsson, an ecologist at Lund University in Sweden. "In the long run, that's going to make the hunted forest look quite different from what they do today."
The hunting could also impact the people who rely on fruits from the trees for food, Olsson added.
Population increases have forced people to live at the forest's edges. Protein-rich food is often scarce, and there are few taboos against eating nonhuman primates.
New roads, guns and cars also enable people to hunt gorillas and bring carcasses to city markets, where they fetch a handsome sum, Olsson said.
Hunted and protected
To find out how primate hunting affected the forest, Olsson and his colleagues surveyed trees and mammals in the Nigerian rain forest bordering Cameroon. Park rangers protected some forested areas, which teem with monkeys and gorillas, while nearby hunted areas were full of rodents such as rats and porcupines.
Whereas similar large trees dominated both types of forest, the seedlings looked very different.
Well-protected forests had many seedlings, such as the bush mango, that rely on primates to spread their seeds. Many of these trees bear fruits or nuts that humans also eat.
Hunted forests held seedling species that relied on wind to disperse their seeds.
In a generation, that could fundamentally change the forest ecology, he said.
And whereas gorilla and monkey meat does provide protein for local people, the fruit trees the primates maintain may be an even bigger economic benefit to people, Olsson said.
The findings show yet another devastating impact of the bushmeat trade, said Joanna Lambert, an ecologist at the University of Texas at San Antonio who was not involved in the study.
"Without primates and other large-bodied mammals, forests are not regenerating in the way they've evolved to do over millions of years," Lambert said.
Ending bushmeat hunting requires several tactics. Increasing fines and enforcement could help, as would improving local populations' access to other protein-rich foods, Lambert told LiveScience.
But another strategy, one that helped gorilla populations rebound in Rwanda and Uganda, is to pay former hunters to serve as park rangers or wildlife guides for tourists, she said.