Putty-Nosed Monkey, Cercopithecus nictitans
PUTTY-NOSED MONKEY
Cercopithecus nictitans
Geographic Distribution and Habitat
Putty-nosed monkeys, also known as the greater spot-nosed monkey or scientifically as Cercopithecus nictitans, are found in central and western Africa in tropical and dense forests. Their habitats include the countries of Cameroon, Central Africa Republic, Congo, Democratic Republic of the Congo, Côte d’Ivoire, Equatorial Guinea, Gabon, Liberia, Nigeria, and have been found in Angola. Living in altitudes as high as 7,217 feet (2,200 m), Putty-nosed monkeys occupy lowland and mid-elevation montane tropical forests and gallery forests at the edge of wetlands. They are arboreal, meaning they live in trees, and prefer the middle and upper layers of the forest canopy, rarely touching the forest floor.
There is some controversy about the number of putty-nosed monkey subspecies. Current literature recognizes two subspecies, the Eastern putty-nosed monkey, Cercopithecus nictitans nictitans and the Bioko putty-nosed monkey, C. n. martini. In previous literature, five subspecies were recognized: insolitus, ludio, martini, nictitans, and stampflii.
Some scientists now suggest that the Stampfli’s, Nigerian, and red-rumped putty-nosed monkeys are more accurately categorized as the same subspecies as the Bioko putty-nosed monkey. This leaves the Eastern putty-nosed monkey (C. n. nictitans) and the Bioko putty-nosed monkey (C. n. martini) as the two predominantly agreed upon subspecies. However, due to insufficient research about the putty-nosed monkey, there is not a solid consensus on exactly the number or identity of the subspecies. That being the case, the following outlines how the five subspecies vary in their appearance and habitat locations across central and western Africa.
Nigerian putty-nosed monkeys, C. n. insolitus, have creamy white fur on their chest and throat that goes to their elbows. They are found in central-southern Nigeria.
Red-rumped putty-nosed monkeys, C. n. ludio, have pure white fur on their chest that extends to their elbows and reddish brown fur on their inner thighs. They are in southeastern Nigeria and southwestern Cameroon.
Bioko putty-nosed monkeys, C. n. martini, are smaller and have longer and darker hair. They are restricted to Bioko Island, Equatorial Guinea.
Eastern putty-nosed monkeys, C. n. nictitans, have more olive-colored fur than other subspecies. They are found in mainland Equatorial Guinea, Gabon, and parts of Cameroon, the Central African Republic, the Democratic Republic of Congo, and the Republic of Congo. They have also been found in Angola.
Stampfli’s putty-nosed monkeys, C. n. stampflii, have a lighter coat color on their backs and tails. They are found across northern Liberia and western Côte d’Ivoire.
Size, Weight, and Lifespan
Putty-nosed monkeys are moderately large monkeys. Male bodies are 21.7-27.6 inches (55-70cm) long with tails that are 26.8-39.4 inches (68-100cm). Females are 16.9-20.9 inches (43-53cm) long with tails that are 22-29.9 inches (56-76cm) long. Adults weigh approximately 12 pounds (5.44kg) and start out at only 0.9 pounds (0.4kg) when they are born. Sexual dimorphism is present in this species with males larger than females who weigh only 60% as much as their male counterparts.
The putty-nosed monkey’s lifespan is about 20 in the wild, but they can live up to 31 years in captivity.
Appearance
The putty-nosed monkey is known for their signature white nose. Their overall coat color ranges from dark and grayish brown, black, and olive. From their whiskers all the way down their back putty-nosed monkeys have many ringed hairs (also known as grizzled hairs). They are a mix of many colors, primarily the general coat color with rings of yellow, making the fur pattern almost look speckled. At the extremities, parts of the arms, hands, feet, legs, and far part of the tail, the fur is black. Beneath the darker coat of their backs and arms, they have lighter whiter or cream fur on their underbellies and the underside of their limbs. They noticeably lack fur on their faces except for their unique facial hair-looking cheek tufts, which accentuate their very large pouches, and a couple of hairs on their upper lip.
Putty-nosed monkeys have amber and red/brown eyes with black sclera. Around their eyes, their skin color ranges from dark orange to blue-gray, green-gray, and brown-gray.
Their non-prehensile tail is a similar coloration as their backs, darker green, black, and gray, but can have a little yellow on the underside.
Diet
The diet of the putty-nosed monkeys is highly variable. Since diet is influenced by habitat, monkeys that live in different forests end up consuming a wide variety of foods. With very few studies researching the diet of these monkeys, it is difficult to understand the exact nuances of their diet. However, putty-nosed monkeys are primarily frugivorous, meaning they consume a lot of fruits and their seeds. They also eat other plants, nuts, and prey on arthropods as an alternative source of protein especially when fruit is scarce. In areas where farming is present, the monkeys are known to raid crops.
Behavior and Lifestyle
Putty-nosed monkeys are extremely active arboreal and diurnal primates. Like many arboreal primates, they spend their day among the branches of the canopy. They almost never touch the ground and call the upper main canopy their home. This is due to direct competition with Diana monkeys (Cercopithecus diana) who also live in canopies. To avoid overlapping ecological niches, putty-nosed monkeys live a little higher up than the Diana monkeys.
While males do not interact with the females or offspring of the group. Females and children have a very tight-knit bond fueled by grooming.
Since they are guenons, putty-nosed monkeys presumably have similar daily lives as other members of their species. However, the lack of research makes it difficult to get an exact understanding of their unique behaviors
A study found that seeds that go through the putty-nosed monkey digestive tract enhance seed germination, making them incredibly important to the ecosystems they live in!
Putty-nosed monkeys are known locally as hocheur in Cameroon.
Males have large air sacs to produce their different calls.
They are not born with their white nose spot.
Putty-nosed monkeys are very social animals, living in a one-male polygynous mating system. A singular male typically lives in family groups with 12 to 30 females and dependent offspring. Since males live in the outskirts of the group they do not interact very much with the females or children, but they are heavily depended on in the case of large threats. When the group is in danger, the male takes to the front line and starts mobbing the predator while females retreat with vulnerable offspring.
Females are philopatric meaning they stay in the group they were born into while males leave once they reach sexual maturity. They move to find a new group or will live in bachelor groups with other guenons until they’re able to find a new home.
Putty-nosed monkeys also spend a lot of time with other guenons and monkey species. They interact frequently with the mustached guenon (Cercopithecus cephus), the crowned guenon (Cercopithecus pogonias), and the gray-cheeked mangabey (Lophocebus albigena). The presence of multiple species increases their chances of survival from predators.
Communication is very important for the putty-nosed monkey. Since they live in an environment with many predators, they have a variety of calls to alert others of danger.
Alarm calls differ between males and females. Females’ only alarm call is the “chirp”, which is immediately responded to with action by the male of the group. Males have a larger variety of calls for different situations. Forest guenons evolved air sacs in their larynxes that allow them to produce high-intensity alarms. Females do not have these air sacs. Males primarily have three loud calls: “boom”, “pyow”, “hack”, and the lesser-known “kek”.
Males “pyow” around the times of dawn and dusk to maintain the space between neighboring groups. If groups are too close together, a “pyow” is followed by a bark, a “hack”. This is typically the start of an aggressive interaction between the two males of the group. A male will also “pyow” in the presence of a terrestrial threat, like a pack of leopards, or an environmental disturbance. They will “hack” in the presence of crowned hawk eagles. “Pyow-hacks” are associated with group movements.
Male putty-nosed monkeys will also respond to another species’ call. Since they live in such close proximity, when a crowned guenon does a “boom” call, the putty-nosed male will respond with a “pyow”. This frequently happens at dawn.
“Boom” calls in the putty-nosed monkey are less frequent. While there is little research on this call, only putty-nosed monkeys in Gabon use it, raising interesting questions about the uniformity of communication across all populations.
Lastly, “keks” are like ”hack” sounds but shorter in duration. “Keks” are only in response to a leopard and are associated with mobbing. Once a “kek” sound is made, in many cases, female alarm calls cease completely.
Like many guenon species, putty-nosed monkeys have a complex communication system. They often combine calls to make sentence-like messages, and their messages can be understood by Diana monkeys as well as mona monkeys, Preuss’s monkeys, and red-eared guenons. The meaning of the message depends on what sounds are included and in what order. For instance, an added sound can convey information like “not urgent,” “urgent,” or “maybe.” Each predator elicits its own designated call. For example, the call when a jaguar is spotted is different from the call for an eagle.
Olfactory communication mostly includes mutual genital sniffing and muzzle sniffing, which are done mainly by males. Muzzle sniffing is performed by a juvenile male to an adult male, when the adult male is giving a loud call.
Visual communication involves staring and head bobbing, which are used as threat expressions. The “fear grimace” is when an individual retracts their lips to show their teeth that are clenched together. This display is a signal to reduce tension.
Putty-nosed monkeys are polygynous, meaning one male mates with many females. While there may be a singular male in a group at a time, they do not stay for their entire lives. Over time, many males will take residence and have offspring.
Males become sexually mature at 6 and females at 4. During estrus or the fertile period, female monkeys will present their sexual swellings to males. They reproduce seasonally, mating in the main dry season in August with births in the shorter dry season in December.
After reaching maturity, females can birth one offspring every two years with a gestation period of 172 days. Once they give birth, the primary caregiver is the mother. Males do not interact socially with the females or offspring of the group so most care falls to the females.
Since putty-nosed monkeys are frugivores, they consume many seeded fruits. Those seeds take root in the location where they were either spit or defecated out. By simply consuming fruits, putty-nosed monkeys have directly improved the dispersal and germination of medium-sized seeds. They have increased in importance since the near-extinction of other large primates in the area.
The putty-nosed monkey is classified as Near Threatened by the International Union for Conservation of Nature (IUCN, 2016), appearing on the IUCN Red List of Threatened Species.
The primary threat to the survival of the putty-nosed monkey is bushmeat hunting and habitat loss. The conversion to farmland and clearcutting of forest habitats has devastated monkey livelihood and is predicted to increase in the coming years.
Aside from harmful habitat disruptions, monkeys in the area have been illegally hunted for bushmeat with an increasing frequency in past years. With newly constructed roads into natural habitats and an increase in human population growth in the area, bushmeat hunting and transportation have been greatly facilitated.
The putty-nosed monkey is an animal of prey. In their natural habitats, they are threatened by crowned eagles and leopards.
Putty-nosed monkeys are listed in Appendix II of the Convention on International Trade in Endangered Species (CITES), an international agreement between governments whose goal is to ensure that international trade in specimens of wild animals and plants does not threaten their survival.
The putty-nosed monkey is protected in Nigeria, Congo, and DRC. They are also protected in Cameroon, CAR, and Equatorial Guinea.
There are many protected areas in the putty-nosed monkey’s natural habitat. Including the world heritage sites of Dja in Cameroon, Lope in Gabon, and the Sangha Trinational in Congo, Cameroon, and CAR. Other protected areas include the Afi Mountain Wildlife Sanctuary, Cross River National Park and Mbe Mountains (in Cross River State), and in the Gashaka Gumti National Park in Taraba State.
- IUCN Red List (https://www.iucnredlist.org/ja/species/4224/222904443#geographic-range)
- CITES (https://cites.org/eng/taxonomy/term/1101)
- Diet of Cercopithecus nictitans and investigation into its potential to act as a surrogate disperser in disturbed Afromontane forests. https://ir.canterbury.ac.nz/server/api/core/bitstreams/b4646a7f-b9d4-496d-af26-03c2d6924c97/content
- Postdispersal Removal and Germination of Seed Dispersed by Cercopithecus nictitans in a West African Montane Forest (https://doi.org/10.1159/000283309)
- Primate Species Spotlight: The Spot-Nosed Guenon – PASA https://pasa.org/awareness/the-spot-nosed-guenon/#:~:text=In%20addition%20to%20the%20spot,predator%20such%20as%20a%20leopard.
- Note, they are primarily discussing the spot-nosed guenon here but mention the putty-nosed monkey as well
- The alarm-calling system of adult male putty-nosed monkeys, Cercopithecus nictitans martini
- Seasonal variation and group size effects in putty‐nosed monkeys’ (Cercopithecus nictitans) heterospecific associations in the Nouabalé‐Ndoki National Park
- AnAge Entry (https://genomics.senescence.info/species/entry.php?species=Cercopithecus_nictitans)
- Mammals of Africa, Volumes 1-6 By Jonathan Kingdon, David Happold, Thomas Butynski, Michael Hoffmann, Meredith Happold, Jan Kalina
- Female putty-nosed monkeys (Cercopithecus nictitans) vocally recruit males for predator defence (doi: 10.1098/rsos.202135)
- Intentional Alarm Calling in Wild Female Putty-Nosed Monkeys (Cercopithecus nictitans)
- Zenodo/Biodiversity Literature Repository: Published as part of Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Cercopithecidae, pp. 550-755 in Handbook of the Mammals of the World – Volume 3 Primates, Barcelona :Lynx Edicions on page 693, DOI: 10.5281/zenodo.6867065
Written by Nami Kaneko, February 2025