Guereza
Colobus guereza

TAXONOMY

Suborder: Haplorrhini
Infraorder: Simiiformes
Superfamily: Cercopithecoidea
Family: Cercopithecidae
Subfamily: Colobinae
Genus: Colobus
Species: C. guereza
Subspecies: C. g. caudatus, C. g. dodingae, C. g. kikuyuensis, C. g. matschiei, C. g. occidentalis, C. g. percivali

Other names: C. guereza: C. abyssinicus, guereza, Abyssinan black-and white colobus, Abyssinian colobus, eastern black-and-white colobus, guereza colobus, guereza black-and-white colobus, magistrate colobus, magistrate black colobus, mantled guereza, white-mantled colobus; colobe à épaules blanches, colobe de l'Abyssinie, colobe guéréza (French); colobo rojo guereza (Spanish); abessinsk guerezavitsvansad guereza, östlig colobusapa, östlig svartvit guereza (Swedish); C. g. caudatus: Kilimanjaro guereza, Kilimanjaro colobus, Mt. Kilimanjaro guereza, white-tailed colobus, white-tailed guereza; C. g. dodingae: Dodinga Hills guereza; C. g. guereza: Abyssinian guereza, guereza, Omo River guereza, Rüppell's guereza, typical guereza; C. g. kikuyuensis: Mt. Kenya guereza, Mt. Kenya colobus; C. g. matschiei: Matschie's colobus, Mau Forest guereza; C. g. occidentalis: Congo guereza, magistrate colobus, western guereza; C. g. percivali: Mt. Uarges guereza, Mt. Uaraguess guereza, Percival's black-and-white colobus.

Groves (2005) lists 7 subspecies; C. g. caudatus, C. g. dodingae, C. g. guereza, C. g. kikuyuensis, C. g. matschiei, C. g. occidentalis, C. g. percivali, while formerly listing (Groves 2001) C. g. gallarum in addition to the aforementioned subspecies. Thus, C. g. gallarum (Djaffa Mountains guereza) persists in the literature on occasion but here is not considered a subspecies.

MORPHOLOGY

The guereza is a large black monkey with a white mantle, or ornamentation, and a tail tuft (Napier 1985). The body is mostly black, with the white mantle extending from the shoulder to the hip, connecting around the lower torso. The tail has a white tuft at its end which is variable in its extent along the length of the tail (Groves 2001). Subspecies are distinguished from one another by color variations in these features (Napier 1985). The face is surrounded by white hair, with bushy cheek hairs. There is a white stripe on the thigh (Groves 2001). In rare instances, almost entirely white individuals are reported from the west side of Mt. Kenya (Hull 1978).

Photo: Michael Pogany

C. g. guereza has a tail which is longer than the head and body combined, with the anterior half being gray and the tuft taking up about half of its length (DL Hull cited in Groves 2001; Groves 2001). The mantle is long and extends onto the back, becoming longer further back on the body (Groves 2001). C. g. dodingae has a tail which is substantially longer than the head plus the body and is white for only 40% of its distal end. This tail tuft is not particularly bushy. The hair is short and coarse and the mantle is only somewhat creamy in color, and does not expand up onto the dorsum (Groves 2001). C. g. matschiei has a tail which is significantly longer than the head and body with the tuft extending over less than half of its length. It has short hair with a yellowish mantle which does not extend onto the back but extends nearly to the white hairs around the face. The shoulders have some white (Groves 2001). The tail of C. g. occidentalis is longer than the head and body combined and the tuft extends only one-third of the tail from the distal end. The mantle is more a cream color than white and does not extend onto the back. The subspecies has some white on its shoulders (Groves 2001). C. g. percivali has a very long creamy yellow mantle and very long hair, extending longer than 40 cm (15.7 in) on the lower abdomen. The tail is as long as the head and body combined, with the white tuft extending over about two-thirds of its length (Groves 2001). C. g. kikuyuensis has a very large tail tuft, covering almost three quarters of its length and the anterior portions of the tail are grayish. The tail is roughly as long as the body and head together. The mantle is long, extends onto the back, and is over 40 cm (15.7 in) long on the lower abdomen. The thigh stripe is abbreviated (Groves 2001). C. g. caudatus has a longer mantle than C. g. kikuyuensis, its ventrum is less woolly, and over 80% of the tail is occupied by the tuft (DL Hull cited in Groves 2001; Groves 2001).

Average weights for males fall between 9.3 and 13.5 kg (20.5-29.8 lbs) while for females, the range of averages is between 7.8 and 9.2 kg (17.2-20.3 lbs) (Napier 1985; WL Junger pers. comm. cited in Oates et al. 1994; Oates et al. 1994; Smith & Jungers 1997). Head and body length in males averages 61.5 cm (24.2 in) ranging from 54.3 to 69.9 cm (21.4-27.5 in). In females, it averages 57.6 cm (22.7 in) and ranges between 52.1 and 67.3 cm (20.5-26.5 in) (Napier 1985).

Colobus guereza, like other Colobines, possesses a large and multi-chambered stomach which allows them to better digest plant fibers, including foliage. This ability to digest plant material is also assisted by bacteria in certain areas of the stomach. Together, these and other morphological adaptations allow the species to feed on large quantities of leaves (Oates & Davies 1994b).

There is a range of dental sexual dimorphism throughout the subspecies of C. guereza, ranging from males having consistently larger teeth than females (e.g., C. g. caudatus), to similar dentition between the sexes (e.g., C. g. guereza), to instances where some female dentition is actually larger than male dentition (e.g, C. g. gallarum). In addition, in some cases, differences in canine size are reduced. These differences could be attributable to habitat and socio-sexual factors (Hayes et al. 1995).

Guerezas primarily use quadrupedal locomotion and leaping to move through their environment, followed in frequency by climbing and other locomotor patterns (Mittermeier & Fleagle 1976; Morbeck 1977a; 1977b; Gebo & Chapman 1995; 2000). The species' quadrupedal movement usually consists of bounds and gallops up and across large supports and when not moving, they will usually sit or recline (Mittermeier & Fleagle 1976; Gebo & Chapman 1995; 2000). Leaps are usually short and contribute to a generally horizontal or downward pattern of movement (Morbeck 1977a; Gebo & Chapman 1995). The species rarely is seen suspending and usually feeds above a support (Mittermeier & Fleagle 1976). While primarily arboreal, the species will descend to the ground to feed and to travel in cases were there are not suitable arboreal pathways (Oates 1977b).

The guereza thumb is rudimentary and greatly reduced like most members of the colobus family (Napier 1985; Oates & Davies 1994b; Tague 2002).

In captivity, guerezas have lived past thirty years (Weigl 2005).

RANGE

Guerezas are distributed in a band across the center of Africa, from Nigeria and Cameroon east through the northern Democratic Republic of the Congo, through southern Sudan to Ethiopia, Kenya and Uganda and south into northern Tanzania (Napier 1985; Groves 2001). Within their range, guerezas are reported in the following countries; Cameroon, Central African Republic, Chad, Congo, Ethiopia, Gabon, Kenya, Nigeria, Rwanda, Sudan, Tanzania, Uganda and the Democratic Republic of the Congo (numerous sources compiled by Oates 1977b; Oates & Trocco 1983).

C. g. guereza is found predominantly in Ethiopia, while C. g. occidentalis is found from Uganda west of the Nile, to southern Sudan, to Cameroon and south to Gabon. C. g. dodingae is only found in the southeastern Sudan. C. g. percivali is only found around Mt. Gargues in central Kenya. C. g. matschiei is found in western Kenya and south into northern Tanzania. C. g. kikuyuensis is found in central Kenya and C. g. caudatus is found in Tanzania, primarily in the region of Mount Kilimanjaro (Groves 2001).

HABITAT

Guerezas are tied to habitats that have trees and are present in both deciduous and evergreen forests (Oates 1977b; Oates et al. 1994; Lwanga 2006). They are found in forests and savanna woodlands within and to the north of the moist forests of central Africa, often extending into highland or montane forests (Oates et al. 1994). However, they are found in a variety of habitat types, including primary, secondary, riparian, gallery, and upland forest, especially those near rivers, lakes and with higher elevations (Dunbar & Dunbar 1974; Dunbar 1987; Oates 1977b). The species often prefers disturbed, secondary, or colonizing forests, and prefers degraded forests to old growth when both are available (Thomas 1991; Lwanga 2006). This preference is likely attributable to high species diversity of food trees in some secondary growth forests and may also be explainable in terms of milder chemical defenses in secondary growth species (Oates 1977a; Lwanga 2006). Other habitat types include moist lowland, medium-altitude and highland forests, rainforests, gallery forests, swamp forests and wooded grasslands (Oates 1977b; Dunbar 1987; Oates 1994; Fashing 2001b; Harris & Chapman 2007). Guereza will also occasionally visit swamps (Oates 1978). In addition, they can be found in high forests in mountainous areas, including altitudes up to 3300 m (10,826.8 ft) as well as areas under human use, such as eucalyptus plantations (likely visited to make up for nutritional deficiencies) (Dunbar & Dunbar 1974; Fashing et al. 2007; Harris & Chapman 2007).

Photo: Júlio César Bicca-Marques

Because of their wide distribution, both in location and altitude, average temperatures and rainfall figures can vary considerably between and even within study sites. At the Kibale National Park in western Uganda for example, daily annual temperatures in the moist evergreen forest range on average between 16.2°C and 23.3°C (61.2 °F and 73.9°F) with average rainfall values ranging between 157cm (61.8 in) and 175 cm (68.9 in) (Butynski 1990; Chapman et al. 2002). Being near the equator, only rainfall shows seasonal variation, peaking between March and May as well as between August or September and November (Oates 1977a; Chapman et al. 2002).

ECOLOGY

Leaves and fruit are the main foods of the guereza but the diet is quite variable as would be expected in a species with such a wide distribution and range of habitat types (Oates 1994; Fashing 2001b). While the species has historically been believed to be exclusively leaf-eaters, they are not obligate folivores (Oates 1994; Fashing 2001b). The proportions of these types of food relative to one another varies by study site and time of year, often with leaves making up more than half to most of the diet, but with fruit sometimes predominating (Dunbar & Dunbar 1974; Oates 1994; Bocian 1997 cited in Kirkpatrick 1999; Fashing 1999; 2001; Harris & Chapman 2007). Fleshy fruits are usually consumed when unripe, with consumption being reduced as they fully ripen, likely to avoid competition with other primate species who prefer ripe fruit (Fashing 1999; Chapman et al. 2006; Harris & Chapman 2007). Often, while a number of species of plant are exploited, only several make up the majority of the diet at a specific site (Dunbar & Dunbar 1974; Clutton-Brock 1975; Oates 1977a; Dunbar 1987; Fashing 2001b; Preece 2006; Harris & Chapman 2007). The usual guereza pattern is to eat and select for young leaves, but in times of scarcity, to rely on mature leaves and fruit. However the use of mature leaves can vary widely across forests and between groups within the same forest (Oates 1977a; 1994; Preece 2006; Chapman et al. 2006; Harris & Chapman 2007). In addition, the possibility exists that fruit might be a preferred food item in some habitats (Fashing 2001b). Other foods consumed include bark and wood, seeds, flowers, petioles, lianas, arthropods, water-plants, concrete from buildings and soil (Oates 1978; Bocian 1997; Fashing 2001b; Chapman et al. 2006; Plumptre 2006; Fashing et al. 2007; Harris & Chapman 2007). Guerezas tend to eat foods with high protein-to-fiber ratios, and the availability of such foods is correlated with guereza biomass in a given habitat (Chapman et al. 2004). Finally, it is supposed that the species is flexible with its dietary needs, a factor which might allow its widespread distribution (Fashing 2001b).

The diurnal guereza spends over half of its day resting (Oates 1977a; von Hippel 1996; Bocian 1997; Fashing 1999; 2001). The next most common activity is feeding, which also takes up a significant amount of time although sometimes locomotion is the second most common activity (Oates 1977a; von Hippel 1996; Bocian 1997; Fashing 1999; 2001). Other activities that occur far less frequently include vigilance, moving, grooming, greeting, clinging and play (Oates 1977a; von Hippel 1996; Fashing 1999). During the day, activities generally consist of periods of moving and feeding, punctuated by prolonged rest periods. This pattern is variable in number of times per day between study sites and specific days, but usually cycles around 3-5 times per day (Dunbar & Dunbar 1974; Oates 1977a; Bocian 1997). Guerezas leave the area around their sleeping trees one to several hours after sunrise and retire to sleeping trees by sunset (Bocian 1997). Groups occupy up to four nearby tall sleeping trees which are near food sources each night and try to avoid sleeping near other guereza groups (von Hippel 1998).

C. guereza occidentalis
Photo: Alain Houle

Home range is variable with study location, with full home range estimates ranging from just over .01 km² to 1 km² (.004 mi² to .4 mi²) with most estimates at the lower end of this range, usually under around .2 km² (.08 mi²) (Oates 1977a; 1977c; review of 11 studies recording home range in von Hippel 1996; Bocian 1997; Krüger et al. 1998; Fashing 1999; 2001a; Chapman & Pavelka 2005). Home ranges can overlap, often sharing home range area with several other groups (von Hippel 1996; Krüger et al. 1998; Fashing 2001a; Harris & Chapman 2007). In addition, there are core areas within the home range which are significantly smaller than the overall home range (Krüger et al. 1998; Fashing 2001a; Harris & Chapman 2007). When compared between study sites, groups are typically between 6 and 10 individuals and usually average under 12 individuals (Oates 1994; Krüger et al. 1998; Fashing 2007). In long-term studies, single-group day range averages were between 252 and 734 m (826.8 and 2408.1 ft), ranging as small as 62 m (203.4 ft) in a day to over 1360m (4461.9 ft) (Oates 1977a; Bocian 1997; Grimes 2000; Fashing 2001a).

The main confirmed predator of the guereza is the crowned hawk-eagle (Stephanoaetus coronatus) (Oates 1977a; Struhsaker & Leakey 1990; Mitani et al. 2001; Fashing & Oates cited in Fashing 2007). A second predator of guereza is the chimpanzee (Pan troglodytes), which has been observed both successfully and unsuccessfully hunting the species (Suzuki 1975; Ihobe 2001). Leopards (Panthera pardus) are also potential predators of the species as guereza remains have been found in its scats. However, the species could also have fed upon carcasses deposited by eagles or resulting from falls (Hart et al. 1996). Other potential predators include other raptors such as Verreaux's eagles (Aquila verreauxii) (Dunbar & Dunbar 1974).

The guereza is often found living in sympatry with a number of other primate species. At the Ituri Forest, in the Democratic Republic of Congo, guerezas are part of one of the richest primate communities in the world. Here, they are found living in sympatry with Cercocebus albigena, C. galeritus, Cercopithecus hamlyni, C. l'hoesti, C. mitis, C. neglectus, C. pogonius, Colobus angolensis, Piliocolobus badius, Pan troglodytes, and Papio anubis (Thomas 1991). Other primates with which they are sympatric include but are not limited to Chlorocebus aethiops, Cercopithecus ascanius, Galago demidoff and Perodicticus potto (Bocian 1997; Grimes 2000; Stern & Goldstone 2005). In addition, infant guerezas will sometimes play with infant vervets (Chlorocebus aethiops) and the species will also sometimes associate with other sympatric species as well (Rose 1977; Chapman & Chapman 1996).

Content last modified: May 12, 2009

Written by Kurt Gron. Reviewed by Peter Fashing and Tara Harris.

Cite this page as:
Gron KJ. 2009 May 12. Primate Factsheets: Guereza (Colobus guereza) Taxonomy, Morphology, & Ecology . <http://pin.primate.wisc.edu/factsheets/entry/guereza>. Accessed 2013 May 21.