World’s first photo of monkey thought extinct in Congo

April 15, 2015

Summary: For the first time ever, primatologists have been able to photograph the critically endangered

Bouvier’s red colobus in the Republic of Congo. The photograph, taken by a primatological expedition

seeking to establish its distribution, adds to the information on the distribution and conservation status of

this endemic red colobus monkey. Recent surveys by the Wildlife Conservation Society had previously

recorded red colobus in a new National Park in the north of the country in 2007 and 2014, but they were

very rarely encountered and no photograph had been taken. The present expedition visited both this park

and ranged more widely in this relatively remote region but found that it was subject to commercial

hunting, which has serious impacts for red colobus monkeys.

Background: Bouvier’s red colobus (Piliocolobus bouvieri) is a species of monkey endemic to the Republic

of Congo, about which virtually nothing is known. The species was described in 1887 and is only known

from a couple of museum specimens collected from three localities over 100 years ago. The authors of a

book written in 1949 mention that the species occurs in the swamp forests between the lower Likouala

and Sangha Rivers, as well as along the Alima River and further to the south.

No photo: Until recently, no photo of a living Bouvier’s red colobus existed and some conservationists

even doubted whether they still remained in the wild. The Wildlife Conservation Society (WCS) carried

out surveys in 2007 and 2014 in the area which became the Ntokou-Pikounda National Park in 2013,

located just north of the Equator. They recorded red colobus in extremely low numbers, but were unable

to photograph them. Further to the south in the Lefini area where they had been recorded in the past,

WCS surveys in the mid-1990s and again in the 2000s failed to reveal any sign of them. Given the

demand for bush meat in large cities like Brazzaville, it is very unlikely that red colobus still exist in that

southern area today.

Expedition: An expedition, led by field primatologists Lieven Devreese and Gaël Elie Gnondo Gobolo, set

off in February 2015 to try to photograph Bouvier’s red colobus and establish the present distribution of

this unique primate species in the Republic of Congo. The expedition was partially crowdfunded, with

additional financial support provided by Primate Conservation Inc., GaiaZoo, Apenheul, and La Vallée des

Singes Primate Parks. WCS helped with logistical support and provided the unpublished survey records of

red colobus in Northern Congo.

Discovery: Guided by local people who know red colobus vocalisations and their appearance well, the

team found a group in the swamp forests along the Bokiba River in the Ntokou-Pikounda National Park.

"Our photos are the world’s first and confirm that the species is not extinct,” Devreese says.

Challenges: The expedition members had to deal with tough conditions in a remote and swampy area.

“All transport occurs on the river, which is expensive, and the forest is often not easily accessible

because of the water level,” explains Devreese. “Wading through waist-deep mud doesn’t make it easy

to look for monkeys.” The remoteness of the area entailed more challenges. “The people are not used to

see biologists with binoculars and GPSes deep in these forests and that sometimes raised suspicion, at

least initially.”

Local informants: However, the expedition did gather interesting data on the monkeys’ current

distribution. “We relied mostly on information provided by local hunters. We asked them to name and

describe all monkeys they know and checked their reliability by testing their knowledge of vocalizations

of different monkey species in the Congo Basin,” Gnondo Gobolo explains.

Findings of the expedition: Although the primatologists were not able to locate red colobus further

downstream despite their searches, they believe the species is present all along the Likouala and Sangha

Rivers, but not on both sides. According to the local people, the red colobus to the east of the Sangha

have a more blackish coat, which is likely to be the other species of red colobus in Congo, the Central

African red colobus (Piliocolobus oustaleti). Because the water level made searching difficult, and animals

are rare due to hunting in these forests, the team was not able to confirm this with their own eyes.

Gnondo Gobolo continues: “All hunters told also us there are no red colobus on the right bank of the

Likouala and none near the Alima River.” Because this last river was mentioned before as part of the

species’ range, this might indicate red colobus have been locally hunted out along the Alima River.

Threats to red colobus: Red colobus are often favoured by hunters. The large monkeys are noisy, travel

in large groups and are not good at detecting hunters. Once a hunter locates a red colobus group, the

monkeys regularly show curious or sometimes even aggressive behaviour and rarely adopt a hide-and-

wait strategy like other monkeys do. This makes them easy targets. All over Africa red colobus are

extremely vulnerable to overhunting.

Bush meat trade: “When talking to the local people, we learned there is an active trade of bush meat

using the rivers as highways. When the forests are not inundated, only a couple of months a year,

commercial hunters shoot whatever they can and empty the forest,” Devreese says. Local people claim

they don’t like the taste of red colobus, but most meat is smoked and transported to city markets.

Hunting is traditionally part of the Central African culture, but the population increase in the cities, the

relatively higher purchasing power of some urban dwellers, and the easy availability of firearms, has

altered the scale of the trade, putting an enormous pressure on wildlife. The team found an even more

disturbing discovery. “Huge dug-out canoes loaded with deep freezers and generators go up the river to

collect meat from the most remote villages and hunting camps,” Devreese explains.

Conservation status: The field biologists will now start working on the data and will make their findings

known to the conservation community. Bouvier’s red colobus is listed as Critically Endangered by the

IUCN Red List as it is thought to have undergone a serious decline in population size caused by hunting.

The researchers estimate that the species’ habitat ranges around 10,000 square kilometres (3,900 square

miles), or an area a third the size of Belgium, but in reality probably significantly less. Precise data on its

conservation status are not available. “Based on our preliminary survey it is hard to estimate how critical

the situation is, but the fact that we didn’t find red colobus along the Sangha and the presence of

commercial hunting doesn’t sound promising,” the scientists explain. “For a species that can be hunted

so easily, up to 50 or 60 monkeys can be killed in one hunting trip, it is clear that uncontrolled hunting

can quickly lead to catastrophic declines.”

Hope for the future: However, there is still hope for the survival of Bouvier’s red colobus. Some areas

deep in the swamps are too difficult to access, even for the most driven commercial hunter. These areas

far away from the villages might harbour relatively untouched monkey populations, although no scientist

has ever been there to confirm. Devreese and Gnondo Gobolo noted another phenomenon. “Many

people told us they stopped hunting monkeys in recent times as the consumers don’t buy monkey meat

anymore because of the perceived risk of getting Ebola through eating monkeys.”

National Park: The expedition team photographed Bouvier’s red colobus in a protected area, the

Ntokou-Pikounda National Park, officially created only two years ago. “At the moment the park mainly

exists on paper, but I had the impression that commercial hunting has been banned already,” Devreese

explains, adding the park has a team of park rangers and other staff. According to Devreese, the

Congolese government doesn’t have funding available to cover the expenses of managing and

developing the new National Park. The researchers hope their findings will encourage international

organizations to get involved. Active protection and monitoring of the new park are needed to ensure

conservation of the endemic Bouvier’s red colobus and other wildlife of the Congolese swamp forests.

Lieven Devreese (27) is an independent researcher with experience on several projects in Central Africa.

For his Master thesis he studied agile mangabeys in the Central African Republic in 2010. Devreese hopes

to start a PhD project soon with a subject on phylogeography of monkeys in the Congo Basin.

Gaël Elie Gnondo Gobolo (25) is a student at the Marien-Ngouabi University in Brazzaville. He grew up in

the village of Bomassa, close to the Nouabale-Ndoki National Park in the Republic of Congo. Gnondo

Gobolo conducted his Bachelor thesis in collaboration with WCS working in this National Park in the

north of the country.

The world’s first photo of Bouvier’s red colobus (Piliocolobus bouvieri) taken early March 2015 in the

Ntokou-Pikounda National Park in the Republic of Congo. The photo shows an adult female with

offspring. Photo: Lieven Devreese.

Map of the expedition area showing the route the team followed, the Ntokou-Pikounda National Park

where Bouvier’s red colobus was observed, and the different sites where information was obtained from

local hunters. Map: Lieven Devreese.

© Lieven Devreese

E-mail: lieven_devreese@hotmail.com

Telephone: 0032 495 270858

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