Greater Spot Nosed Guenon

Maximum longevity: 31 years (captivity)

Male Cercopithecus nictitans sound resonating alarm calls to warn the group of predators and enemies. Their dark coloring also acts as camouflage within the dark tree canopy, allowing them to hide from predators, such as leopards, crowned eagles, and humans.

Known Predators:

• leopards (Panthera pardus)
• crowned eagles (Stephanoaetus coronatus)
• humans (Homo sapiens)

Anti-predator Adaptations: cryptic

Cercopithecus nictitans, also known as white-nosed guenons, greater spot-nosed monkeys, greater white-nosed monkeys, or putty-nosed monkeys, is most easily recognized by a distinctive white spot covering the nose. Their fur is dark, ranging in color from olive to black, and sometimes have a white patch on the breast. They have cheek pouches in which to store food while foraging. Individuals weigh, on average, between 4.2 and 6.6 kilograms, making them one of the largest of the Cercopithecus group. Sexual dimorphism is evident, with males exhibiting a greater length and body mass than females. They are diurnal and, like all guenons, possess trichromatic vision. Greater spot-nosed monkeys are primarily arboreal, but also move through the forest quadrupedally. Grubb et al. (2003) recognized two subspecies, C. nictitans nictitans and C. nictitans martini, based on geographic range. Cercopithecus nictitans nictitans occupies the eastern section of the range, from Cameroon to the Democratic Republic of the Congo. Cercopithecus nictitans martini is thought to represent the western populations of several distinct subspecies, such as one on the island of Bioko.

Range mass: 4.2 to 6.6 kg.

Other Physical Features: endothermic ; heterothermic ; bilateral symmetry

Sexual Dimorphism: male larger

Longevity in the wild has not been recorded, but like other Cercopithecus species, greater spot-nosed monkeys probably live for approximately 20 years.

Range lifespan
Status: captivity: 31 (high) years.

Cercopithecus nictitans is found in the moist tropical lowland and montane forests, tropical swamp and mangrove forests, and dense gallery forests of west and central Africa. Activity is mostly confined to the main canopy layer due to their robust size. They descend voluntarily to the ground only rarely.

Habitat Regions: tropical ; terrestrial

Terrestrial Biomes: forest ; rainforest

Wetlands: swamp

Cercopithecus nictitans occupies a variety of dense forest habitats in western and central Africa, ranging from Guinea in the west to the Democratic Republic of the Congo in the east. Populations are found in Guinea, Liberia, Ivory Coast, Nigeria, Cameroon, Equatorial Guinea, Gabon, Central African Republic, Congo, and the Democratic Republic of the Congo.

Biogeographic Regions: ethiopian (Native )

The taxonomy of Cercopithecus nictitans is contentious. Grubb et al. (2003) list two subspecies, the geographically widespread C. nictitans nictitans and the more restricted C. nictitans martini, but an isolated population of the latter is thought to represent a distinct and possibly threatened subspecies. A recent morphometric analysis (Cardini & Elton, 2008) misclassified Cercopithecus diana within the Cercopithecus mitis species group, which includes Cercopithecus nictitans, Cercopithecus albogularis, and Cercopithecus mitis. The inclusion of Cercopithecus nictitans within the Cercopithecus mitis species group was confirmed by a recent molecular analysis (Tosi et al., 2005), which supports Cercopithecus albogularis as the sister taxon of C. nictitans.

Cercopithecus nictitans is colloquially known as the “cowardly monkey” because of its high frequency and range of alarm calls.

Auditory, olfactory, visual, and tactile senses are complex, as in most primates. Greater spot-nosed monkeys are especially known for their wide range of vocalizations, which vary from deep booms to chirps, depending on context. Males perform loud, low-frequency boom calls to communicate territoriality and as a predator alarm call. Females and subadults often use short chirps to attract the attention of the group. Loud isolation calls are emitted both by infants and members of the group that have become separated from the troop. Olfactory communication includes mutual genital sniffing and muzzle sniffing, both of which are performed by males. Visual signals include staring, which is often accompanied by head-bobbing in order to indicate a threat display among males. Grimacing or yawning with the canines exposed is an expression of tension or a threat display.

Communication Channels: visual ; tactile ; acoustic

Perception Channels: visual ; tactile ; acoustic ; chemical

Greater spot-nosed monkeys are threatened by habitat loss through deforestation and by hunting for meat, especially in the western portion of its range. On the island of Bioko, populations of C. nictitans martini have undergone steep declines, exceeding 50% during the period of 1986 to 2006.

Populations are known to occur in several protected national parks in Equatorial Guinea and Cameroon. They are listed on Appendix II of CITES and on Class B of the African Convention on the Conservation of Nature and Natural Resources.

Cercopithecus nictitans nictitans is currently listed as Least Concern by the IUCN due to its widespread range and relatively slow rate of population decline. Cercopithecus nictitans martini is classified as vulnerable due to restricted habitat range, ongoing habitat loss, and hunting pressure.

US Federal List: no special status

CITES: appendix ii

Greater spot-nosed monkeys, like other guenons, have been reported to feed on agricultural crops.

Negative Impacts: crop pest

Cercopithecus nictitans is hunted and eaten by humans. They may positively impact forest diversity through seed dispersal.

Positive Impacts: food

Like many other frugivorous Old World monkeys, Cercopithecus nictitans likely plays a large role in seed dispersal, as they often ingest fruits and seeds away from the parent site. Cercopithecus nictitans has been reported to live in mixed-species groups with Cercopithecus diana for mutual predator defense and increased foraging opportunities. Humans (Homo sapiens) hunt them for bushmeat, and also to prevent the greater spot-nosed monkeys from destroying their crops. Greater spot-nosed monkeys carry a variety of parasites, including a primate-specific strain of malaria (Plasmodium falciparum).

Ecosystem Impact: disperses seeds

Commensal/Parasitic Species:

• Entamoeba coli
• Endolimax nana
• Strongyloides fuelleborni
• Ascaris
• Ancylostoma
• Plasmodium falciparum
• Trichuris
• Capillaria
• Enterobius

Greater spot-nosed monkeys are primarily frugivorous and granivorous. Like most Old World Monkeys, they have cheek pouches in which to store seeds while foraging. They supplement their diets of fruits and seeds with leaves and insects, and occasionally agricultural crops.

Animal Foods: insects

Plant Foods: leaves; seeds, grains, and nuts; fruit; flowers

Primary Diet: herbivore (Frugivore , Granivore )

Greater spot-nosed monkeys have a polygynous mating system, in which one resident adult male resides with several adult females and their offspring. The lone male has exclusive breeding access to all of the females. Male tenures of 5 years are common. Females solicit copulation by presenting their estrous swellings to males. During copulation, the females look over their shoulders and pout, with the lower lip pushed forward and down. Greater spot-nosed monkeys exhibit female philopatry, in which males disperse from natal groups upon adolescence and females stay in their natal range.

Mating System: polygynous

Females reach maturity around 4 years of age. Once pregnant, they gestate for 172 days on average. They give birth to one offspring approximately every two years. There is little information available on the reproductive cycle, breeding season, and parental investment of greater spot-nosed monkeys. However, it is assumed that, like other Cercopithecus species, the young are relatively well-developed at birth and that mothers will invest in their own offspring for approximately six months.

Breeding interval: Greater spot-nosed monkeys breed once every two years.

Breeding season: Breeding season is unknown, but it is probably year-round, as in Cercopithecus mitis.

Average number of offspring: 1.

Average gestation period: 172 days.

Average time to independence: 4 years.

Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous

There is little information regarding the level of parental investment in Cercopithecus nictitans, although females certainly invest heavily in offspring through gestation, lactation, and juvenile protection.

Parental Investment: precocial ; female parental care ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)

Noisy and gregarious, the tree-dwelling greater spot-nosed guenon generally lives in large groups of between 12 and 30 animals, comprising a single adult male, with several females and their young (1) (5).This species is frequently found in close association with related guenon species, such as the crowned guenon (Cercopithecus pogonias), forming large, mixed-species groups. This helps to protect against predation, and also allows the sharing of information about the best foraging locations (6). While the bulk of the greater spot-nosed guenon's diet consists of fruit, seeds and leaves, it will also eat insects and agricultural crops (2) (3). Male greater spot-nosed guenons produce a range of vocalizations including deep, booming calls to advertise status and presence, as well as “pyow” and “hack” alarm calls. Incredibly, the sequence of these two alarm calls can convey information to other greater spot-nosed guenons about what kind of predator is nearby, for example, whether it is a bird of prey or a leopard, allowing the group to take the appropriate evasive action (5). Greater spot-nosed guenon mating systems are usually polygynous, with the lone male in each group having exclusive breeding access to all the females (5) (7). Breeding is likely to occur throughout the year (7), with the females giving birth to a single young (2) after a gestation period of around five or six months (3) (7).

The greater spot-nosed guenon occurs in a number of protected areas throughout its range, and is therefore safeguarded to some extent from habitat loss (1). In order to protect this species against unsustainable levels of international trade, the greater spot-nosed guenon is listed on Appendix II of the Convention on International Trade in Endangered Species (CITES) (3). In addition, this species is listed on Class B of the African Convention on the Conservation of Nature and Natural Resources, and therefore legal hunting requires authorisation (1) (8). Despite these controls, the bushmeat trade for the greater spot-nosed guenon—along with many other species—continues to grow (9) (10). To combat this, on Bioko, the Bioko Biodiversity Protection Program is working to protect the island's threatened wildlife by patrolling protected areas to deter hunters, and by developing research and educational programs (9). At an international level, the Bushmeat Crisis Task Force, a consortium of several conservation organisations, is working with governments, organisations and the general public in order to eliminate unsustainable and illegal bushmeat hunting practices worldwide (10).

One of the larger guenon species, the greater spot-nosed guenon's name is derived from the striking, bright, white patch found on the nose (2). The coat is finely speckled dark olive and blackish-grey on the upperparts, while the extremities, belly and tail are black (2) (3).

The greater spot-nosed guenon is primarily found in lowland and montane primary tropical rainforest, but also occurs in forested areas bordering rivers, and in secondary forest (1) (2).

Although the taxonomic status of this species is still unclear, there are currently two generally recognised subspecies of greater spot-nosed guenon, which are found in different locations. The most widespread subspecies, Cercopithecus nictitans nictitans is found from southern parts of Cameroon and the Central African Republic, southwards, through northern Democratic Republic of Congo, Congo, Equatorial Guinea and Gabon. In contrast, Cercopithecus nictitans martini is found north of the Sanaga River in Cameroon, and in western and southern Nigeria. Isolated populations also occur in Liberia, Côte d'Ivoire and on the island of Bioko (1).

Classified as Least Concern (LC) on the IUCN Red List (1) and listed on Appendix II of CITES (4). Subspecies: Cercopithecus nictitans martini classified as Vulnerable (VU) on the IUCN Red List (1).

The main threats faced by the greater spot-nosed guenon are habitat loss, through deforestation for timber and agricultural land, and hunting for meat. Currently these threats are most prevalent in the western part of this species' range, where the subspecies Cercopithecus nictitans martini occurs. In particular, on Bioko Island, where hunting pressure is severe, the population of Cercopithecus nictitans martini has undergone a severe decline, with 50 percent of the population lost between 1986 and 2006. As a result, this subspecies is considered to be more at risk than Cercopithecus nictitans nictitans, and is therefore classified as Vulnerable by the IUCN (1). A further concern for this species is the uncertainty about its taxonomic status. At present, there are a number of differing forms of greater spot-nosed guenon that are grouped under the subspecies Cercopithecus nictitans martini. Should these groups become recognised as distinct subspecies, many would be considered to be perilously close to extinction (1).

The greater spot-nosed monkey or putty-nosed monkey (Cercopithecus nictitans) is one of the smallest Old World monkeys. It is a guenon of the C. mitis group, native to West Africa and living to some extent in rain forests, but more often in the transition zone between rain forest and savannah. It is primarily arboreal and often associates with monkeys of other species. Both their common names come from the monkeys' prominent white nose.

The greater spot-nosed monkey lives in groups consisting of one adult male, a number of adult females, and their dependent offspring. Little recent research has been conducted into its behaviour, and most has concentrated on its auditory communication. Males use three call types which have been described as 'booms', 'pyows', and 'hacks'. These are used in a number of contexts including as alarm calls.

As in some other species of monkeys, the acoustical structure of greater spot-nosed monkey alarm calls it has been argued to vary according to the kind of predator spotted. The monkey reportedly combines different sounds into a sequence, which has an entirely different meaning from the sounds out of which it is made.