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.