Hearing the dreaded sound of human footsteps, three enormous gorillas jump down from the branches of central Gabon's lush rainforests and rush off into the distance.
To photographer and wildlife lover Max Hurdebourcq, who spends half his year living alone in the heart of west Africa's tropical rainforest, the gorillas' fearless flight is a positive sign that things are changing.
"That was great contact! They didn't shriek, and that means they aren't too bothered by our presence here," the Frenchman beamed.
Hurdebourcq has been working in Gabon for seven years, mending relations between gorillas and humans by protecting the primates' natural habitat.
In 2008, he knew "very little about Africa" when he travelled to Gabon on a reporting trip to a 600,000-hectare (1.5 million-acre) timber project in eastern Gabon, the Equatorial Woods Company (CEB), most of whose shares are owned by the Swiss company Precious Woods.
He saw elephants, buffaloes, antelopes, chimpanzees and gorillas' everyday lives disrupted by the logging company.
"I wondered how they (the animals) adapted to the noise of the machines, and to the roads that were being built around their natural habitat," Hurdebourcq said.
Enraged by what he saw, he decided to leave everything behind and to found the Bambidie Gorilla Project.
Now, the gorilla defender works around the clock to help save a species of primate that is less well known than its relatives in Rwanda, Uganda and the Democratic Republic of Congo.
Eighty percent of oil-rich Gabon is covered by rainforest, much of which is split up by timber processing licenses.
Only 11 percent of the country's territory is classed as national park.
Seven years of hard work in tough conditions have allowed Hurdebourcq to understand the behaviour and movement patterns of gorillas, whose survival is under constant threat because of deforestation and the bushmeat trade.
Hurdebourcq believes that animal rights should not be limited to the protected environment of national parks. Gorillas should also be able to co-exist peacefully with human life, even with major logging operations like CEB's, he feels.
Armed with the CEB's backing, a dose of good luck and tips from local poachers, the photographer made his way through the dense forests of the logging company's turf, and found what he was looking for: an aquatic plant that gorillas crave.
The plant grows in a clearing that is sunny at times, and flooded when it rains. The photographer hoists himself up onto a platform in the canopy, and waits to film the gorilla families that come to eat at the clearing.
The gorilla clan chief is instantly recognisable thanks to his silver back. He leads the young males and females, as well as their little cubs.
Hurdebourcq has seen nine groups—a total of 80 gorillas—at the remote site.
The photographer's rare images have drawn the attention of major conservationist groups like the international Wildlife Conservation Society, which has offered him support to map out the key sites and to gather data on the gorillas.
'We can live together'
Now, Hurdebourcq wants to convince CEB to set up sanctuaries around the aquatic plant clearings, to make sure that areas the gorillas frequent are kept safe.
But it is proving hard to reconcile the gorillas' needs with one of the region's top employers, which provides for 600 workers and their families—in total, some 3,000 people.
Bambidie forest exploitation director Philippe Jeanmart told AFP: "We can't protect everything in the forest, people need to live... and forestry companies give many communities a livelihood."
He added: "Max's work shows that, through well-managed (forest) operations, we can ensure that both the animals and the ecosystem thrive and ensure that vulnerable species like the gorilla can survive."
But gorillas still face the threat posed by hunters, so Hurdebourcq has set up an awareness-raising programme at the forest schools to try to convince villagers to stop killing the animals.
"Some eat the gorillas, but people often kill them because they are afraid. I try to talk to the children, to show them that (the gorillas') behaviour is very similar to ours. We can live together," he said.
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