“They have a nice black eyebrow, but I especially liked the fluffy white hairs on their cheeks.” For Congolese primatologist Gaël Elie Gnondo Gobolo, seeing Bouvier’s red colobus monkey (Piliocolobus bouvieri) for the first time “was an unexpected moment, like being in a dream”.
No one knew the monkey still existed in the Republic of the Congo. Assessments for the IUCN in 2008 and 2016 classified it as critically endangered, with a note saying it was “possibly extinct”. There had been no recorded sightings since the 1970s until Lieven Devreese, a primatologist from Belgium, led a two-month expedition in 2015. Gnondo Gobolo was a biology student at Marien Ngouabi University in Brazzaville, Congo’s capital, at the time and accompanied him.
Devreese hoped not only to find the Bouvier’s red colobus but also to take the first photograph of the species. The expedition, with financial support from four European organisations (Primate Conservation Inc, GaiaZOO, Apenheul, and La Vallée des Singes), headed to northern Congo and the 457,200-hectare (1,130,000-acre) Ntokou-Pikounda national park.
“It took us a day travelling down the river to reach the village of Ntokou, where we got permission to enter the forest and found a team of local Mbendjele trackers and eco-guards who know the area,” says Devreese. “To enter the park, we travelled for a day in a pirogue up the Bokiba River. Because it was near the end of the rainy season, the river had inundated large tracts of forest. We had to wade through waist-deep mud and cross a swamp covered with spiny raffia palm leaves.
“One of the teams of Mbendjele people found the monkeys and came back to alert us. It took 45 minutes of walking through virgin rainforest at high speed to get to the location, hoping the tracker who stayed with the monkeys hadn’t lost sight of them.
“It was very intense and exhausting, tackling all kinds of stinging lianas, not to mention the heat and lack of water, because we’d only planned to be out in the forest until noon. I felt great relief when I heard the chattering of the red colobus monkeys nearby. Then we saw an adult female with an infant clinging to her belly through an opening in the canopy. Finding them was a special experience.”
The team observed about 20 monkeys in the lower canopy. “Being able to take the first photograph of this species was proof that there’s still much to learn and discover in these forests,” says Devreese.
The monkeys made a big impression on Gnondo Gobolo, who is now a community assistant in Ntokou-Pikounda park.
“There are 18 different species of red colobus monkey, of which the Bouvier’s red colobus have beautiful black hands and feet,” he says.
“I’ll always remember their curious behaviour when we found them in the forest. We were able to observe them for almost an hour, and at one point an adult female with her infant that we had in our view closed her eyes to take a quick nap. Unfortunately, this fearless behaviour towards people poses a serious threat to them.”
Since the rediscovery, Bouvier’s red colobus has been reclassified as endangered. Proof they still exist has aided conservation efforts, with WWF and the government of the Republic of the Congo agreeing to co-manage Ntokou-Pikounda park.
“The joint WWF-government team works with Indigenous people and local communities to manage this exceptional expanse of tropical rainforest,” says park director Victor Mbolo.
Seeing such solid results from the rediscovery is the reward for days wading through swamps, says Gnondo Gobolo. “I feel profoundly happy to have contributed to the success of the mission. These monkeys require special protection. For me, they represent the pride of Congolese biodiversity and Ntokou-Pikounda park.”
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