Animal Diversity Web

Geographic Range

The range of Pennant’s red colobus (Piliocolobus pennantii) has been reduced to only a few small areas in Central West Africa. One subspecies, P. p. pennantii (Bioko red colobus), is present in the southwestern side of Bioko Island. In the eastern and central Democratic Republic of Congo, the subspecies P. p. bouvien (Bouvier’s red colobus) is present. Another subspecies, P. p. epieni (Niger delta red colobus) is aptly named, as it is found in southern Nigeria. ("Bioko Biodiversity Protection Program", 1998; Richardson, 2003)

• Biogeographic Regions
• ethiopian
  • native

Habitat

Pennant's red colobus are arboreal and spend the majority of their lives in the treetops. They can be found at all levels of the canopy in both primary and secondary rainforest. This genus of monkey occurs in higher densities in primary forests than other genera of Colobinae. Some Pennant's red colobus are also found in marsh forests. Unlike members of a similar genus g. Colobus (black and white colobus), Pennant's red colobus are not found in dry forests. In general, this species is found at relatively high elevations. ("The Primata", 2007; Fleagle, 1988; "Honolulu Zoo", 2008; Richardson, 2003)

• Habitat Regions
• tropical
• terrestrial

• Terrestrial Biomes
• rainforest

• Wetlands
• marsh

Physical Description

One of the most striking features of colobus monkeys is their lack of thumbs. A bump remains where the thumb should be, making it look as though the thumb has been cut off. To allow climbing, the other fingers are elongated and form a hook to grip branches. As with many climbing mammals, the limbs of Pennant's red colobus are also elongated. In general, male Pennant's red colobus tend to be larger than females. This speices ranges in mass from 7 to 11 kg. The length of the head and body is usually between 53 and 63 cm, while the tail ranges from 60 to 70 cm. The head tends to be rather small and the belly is round. ("The Primata", 2007; "Bioko Biodiversity Protection Program", 1998; "Honolulu Zoo", 2008; Kavanagh and Morris, 1984; Richardson, 2003)

Subspecies of Pennant's red colobus vary in the coloration of their pelage. The shaggy hair varies between shades of maroon and orange. The crown is usually dark red to nearly black, and the back feet and tail tend to be dark brown. White is often found on the hair of the pubic region. The hair on the forehead is distinctly parted down the center. ("The Primata", 2007; "Bioko Biodiversity Protection Program", 1998; "Honolulu Zoo", 2008; Kavanagh and Morris, 1984; Richardson, 2003)

• Other Physical Features
• endothermic
• bilateral symmetry

• Sexual Dimorphism
• male larger

• Range mass

  7 to 11 kg

  15.42 to 24.23 lb

• Range length

  53 to 63 cm

  20.87 to 24.80 in

Reproduction

Not much is known about the reproduction of Pennant's red colobus, though the reproduction of other species in the subfamily Colobinae is likely similar. The genital area of females swells during estrus. Females use "social presenting" to signal that they are ready to mate. Colobus monkeys breed in a sort of "communal marriage" in which females ready to mate and males retreat from the larger group. Colobus monkeys are polygynous, meaning each male breeds with multiple females. ("The Primata", 2007; "Honolulu Zoo", 2008; Richardson, 2003)

• Mating System
• polygynous
• cooperative breeder

There is no specific breeding season for colobus monkeys, and females give birth approximately every two years. Pennant's red colobus Piliocolobus pennantii give birth to one offspring at a time. The gestation period of this particular species is not known, but the gestation period of other colobus monkeys ranges from five to seven months. After gestation, female colobus monkeys leave the group, accompanied by a single male, and do not return until a day after the birth. In Africa, female Colobinae tend to reach sexual maturity between 3 and 4 years and males between 5 and 6 years. ("The Primata", 2007; "Honolulu Zoo", 2008; "Singapore Zoological Gardens Docents", 2000)

• Key Reproductive Features
• year-round breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• viviparous

• Breeding interval

  Pennant's red colobus breed approximately once every 2 years.

• Breeding season

  There is no specific breeding season for Pennant's red colobus.

• Average number of offspring

  1

• Range gestation period

  5 to 7 months

• Average time to independence

  8 months

• Range age at sexual or reproductive maturity (female)

  3 to 4 years

• Range age at sexual or reproductive maturity (male)

  5 to 6 years

For the first 1 to 3.5 months after birth of Pennant's red colobus, generally only the mother handles the infant. After this time, other group members help care for the young. Mother Pennant's red colobus allow their offspring to hang from their bellies for about 8 months. Young of both sexes have genital regions that mimic those of adult females. This is thought to protect unidentifiably male youth from being expelled from the group by adult males. ("The Primata", 2007; "Honolulu Zoo", 2008; "Singapore Zoological Gardens Docents", 2000)

• Parental Investment
• female parental care
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female
• pre-independence
  • provisioning
    • female
  • protecting
    • female
• post-independence association with parents
• extended period of juvenile learning

Lifespan/Longevity

Little information is available regarding the lifespan of Pennant’s red colobus monkeys. Other members of the subfamily Colobinae have been known to live 25 to 30 years. ("Bioko Biodiversity Protection Program", 1998; "Oregan Zoo Animals", 2005; "Singapore Zoological Gardens Docents", 2000)

Behavior

Pennant's red colobus live in social groups composed of many males and females, usually with a high proportion females. Although females usually stay with the same group, males often move to a new group on several occasions throughout their lifetime. This behavior can result in some all-male groups. While larger groups occasionally displace smaller ones when competing for food, this species is not otherwise known to be territorial. ("The Primata", 2007; "Bioko Biodiversity Protection Program", 1998; Richardson, 2003)

Pennant's red colobus can be described as both diurnal and arboreal. They move through the trees with quadrupedal motion, meaning they use all four limbs to walk along the branches. They also leap through the trees, sometimes using slim branches to launch themselves across breaks in the canopy. ("The Primata", 2007; "Bioko Biodiversity Protection Program", 1998)

• Key Behaviors
• arboreal
• diurnal
• motile
• social
• colonial

• Range territory size

  1 (high) km^2

Home Range

The home range of a group of Pennant's red colobus, which often overlaps with that of other groups, can extend 100 ha or more. (Fleagle, 1988)

Communication and Perception

Pennant's red colobus engage in three major social behaviors. The first of these is social presenting, in which the presenter faces its rear toward the receiver and lifts the hindquarters higher than the rest of the body. This act of submission is performed by all but the adult males. Social presenting usually leads to social mounting. The receiver of the social presenting responds by mounting the presenter in the same manner done during mating. Social mounting displays dominance and is done by all except the least dominant members of the group, infants. Social grooming often follows these behaviors. Through this process, unwanted material, such as dead skin, insects, or parasites, are removed from one individual by another, often using his or her mouth. While the hygienic aspect of this act is rather important, its true purpose is to strengthen the bond between those involved. Social grooming becomes more common when another group is near. Pennant’s red colobus are also known to be rather loud. Noises described as “barks” and “squawks” may be a very important auditory communication between individuals and between troops. ("The Primata", 2007; "Bioko Biodiversity Protection Program", 1998)

• Communication Channels
• tactile
• acoustic

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

Pennant's red colobus search for food in the upper division of the forest and tend to eat in the morning and again in the evening. Their diet consists of foliage in the form of immature leaves and shoots, as well as seeds and fruits. Colobus monkeys have complex stomachs capable of fermentation, allowing them to break down difficult plant materials like cellulose. Because of this fermenting process ripe, sugary fruits result in excess gas and acid formation when eaten. This causes pain and could result in death. Therefore, this species can only digest fruits that are unripe and tough. Pennant's red colobus have also been known to eat fungi and even termite clay. ("The Primata", 2007; "Bioko Biodiversity Protection Program", 1998)

• Primary Diet
• herbivore
  • folivore

• Plant Foods
• leaves
• seeds, grains, and nuts
• fruit

Predation

Chimpanzees are a common predator of red colobus and can reduce populations by as much as 10 % in a year. The large social groups of red colobus are an anti-predatory defense. Some red colobus listen for warming calls of other species of monkeys to alert them to danger. Humans also hunt Pennant's red colobus for meat. (Fleagle, 1988; Strier, 2007)

• Known Predators

  • Chimpanzee Pan troglodytes
  • Humans homo sapiens

Ecosystem Roles

Red colobus monkeys, including Pennant's red colobus, are preyed upon by chimpanzees. This species also acts as a seed disperser, as it consumes fruits and seeds. Social groups of Colobus monkeys compete with each other for food; the most successful competitors are often the largest groups. (Fleagle, 1988; Napier and Napier, 1970; "Singapore Zoological Gardens Docents", 2000)

Colobus monkeys are the only monkeys with a complex multichambered stomach containing cellulose-digesting bacteria. Because of this complex digestive system and relationship with bacteria, colobus monkeys are extremely successful in rainforest habitats in both Africa and Asia. Other Old World monkeys appear to be in direct competition with colobus monkeys for food. However, because of the unique digestive abilities of colobus monkeys, they eat very different proportions of shared resources, and competition is thus less extreme with other Old World monkeys. (Fleagle, 1988; "Singapore Zoological Gardens Docents", 2000)

• Ecosystem Impact
• disperses seeds

Economic Importance for Humans: Positive

The meat of Pennant's red colobus is commonly sold in commercial bushmeat markets. Growing African cities increases the need of animal protein, such as bushmeat. The bushmeat market in West Africa alone is a multibillion dollar industry. Sooty mangabeys, black and white colobus, and red colobus are especially at risk, because they provide hunters with the most profit. (Richardson, 2003; Strier, 2007)

• Positive Impacts
• food

Economic Importance for Humans: Negative

There are no known adverse affects of Piliocolobus pennantii on humans.

Conservation Status

Pennant's red colobus is considered critically endangered by the IUCN. Conservation International named the species as one of the “world’s 25 most endangered primate species” in 2006. A combination of habitat loss and hunting has resulted in low population sizes. Pennant's red colobus are sold in bushmeat markets, and are easy targets for hunters because they are both loud and slow. ("Bioko Biodiversity Protection Program", 1998; Richardson, 2003)

• IUCN Red List

  Critically Endangered

• US Federal List

  No special status

• CITES

  No special status

Other Comments

Pruess's red colobus (Piliocolobus pennantii pruessi) was once considered to be a fourth subspecies of Pennant's red colobus. However, some are now considering it to be an entirely separate species and have given it the new designation of Piliocolobus pruessi. (Richardson, 2003)

Contributors

Kasi Gilbert (author), Northern Michigan University, John Bruggink (editor), Northern Michigan University, Gail McCormick (editor), Animal Diversity Web Staff.

References

Bioko Biodiversity Protection Program. 1998. "Bioko Biodiversity Protection Program" (On-line). Pennant's Red Colobus. Accessed February 15, 2009 at http://www.bioko.org/wildlife/pennanti.asp.

Honolulu Zoo. 2008. "Honolulu Zoo" (On-line). Colobus Monkey. Accessed February 21, 2009 at http://www.honoluluzoo.org/colobus_monkey.htm.

Oregan Zoo, Portland, OR. 2005. "Oregan Zoo Animals" (On-line). Colobus Monkey. Accessed February 21, 2009 at http://www.oregonzoo.org/Cards/Rainforest/monkey.colobus.htm.

Singapore Zoological Gardens Docents. 2000. "Singapore Zoological Gardens Docents" (On-line). Colobines (Colobinae) African Colobus and Asian Langurs. Accessed February 15, 2009 at http://web.archive.org/web/20051203234858/http:/www.szgdocent.org/resource/pp/p-colobn.htm.

2007. "The Primata" (On-line). Pennant's Red Colobus (Procolobus pennantii). Accessed February 15, 2009 at http://www.theprimata.com/procolobus_pennantii.html.

Fleagle, J. 1988. Primate Adaptation and Evolution Second Edition. San Diego, California: Academic Press.

Kavanagh, M., D. Morris. 1984. A Complete Guide to Monkeys, Apes and Other Primates. New York: The Viking Press.

Napier, J., P. Napier. 1970. Old World Monkeys: Evolution, Systematics, and Behavior. New York, New York: Academic Press.

Richardson, M. 2003. "ARKive Images of life on earth" (On-line). Pennant's Red Colobus (Piliocolobus pennantii). Accessed February 15, 2009 at http://www.arkive.org/pennants-red-colobus/piliocolobus-pennantii/info.html.

Strier, K. 2007. Primate Behavior Ecology Third Edition. United States of America: Allyn and Bacon.