Animal Diversity Web

Ge­o­graphic Range

Cephalo­phus sil­vicul­tor is found through­out west­ern cen­tral Africa. Yel­low-backed duik­ers range from Guinea-Bis­sau east­ward to Uganda and Sudan, and as far south as An­gola and Zam­bia. Yel­low-backed duik­ers have the widest range in com­par­i­son to other for­est duiker species. They are typ­i­cally found in forested areas with dense un­der­story growth. ("The En­cy­clo­pe­dia of Mam­mals", 2001; Her­man and Sayama, 1951; Huff­man, 2004)

• Biogeographic Regions
• ethiopian
  • native

Habi­tat

Yel­low-backed duik­ers pre­fer forested habi­tats with dense un­der­growth, al­though they can be found in a va­ri­ety of forested habi­tats, in­clud­ing sa­van­nah and farm­land. There is ev­i­dence of in­ter­spe­cific com­pe­ti­tion be­tween yel­low-backed duik­ers and their larger rel­a­tives, Jentink's duik­ers (Cephalo­phus jentinki). In some sit­u­a­tions, Jentink's duik­ers may force yel­low-backed duik­ers out of pre­ferred habi­tat. (New­ing, 2001)

In cap­tiv­ity, yel­low-backed duik­ers are not tol­er­ant of cold tem­per­a­tures. They can­not be ex­posed to cli­mates of 7 de­grees Cel­sius (55 de­grees Fahren­heit) for a pro­longed time, but can tol­er­ate tem­per­a­tures of 43 de­grees Cel­sius (110 de­grees Fahren­heit). (Barnes, et al., 2002)

• Habitat Regions
• tropical
• terrestrial

• Terrestrial Biomes
• forest
• rainforest

• Other Habitat Features
• agricultural

Phys­i­cal De­scrip­tion

The coat of yel­low-backed duik­ers is black or brown in color with a yel­low tri­an­gu­lar patch near the tail. This yel­low patch typ­i­cally will not ap­pear until about 1 month of age and will not be com­pletely de­vel­oped until about 10 months. Males and fe­males re­sem­ble each other in ap­pear­ance, al­though fe­males are slightly larger. The muz­zle area is a light gray color which sur­rounds their white lips. Both sexes have short, con­i­cal horns that grow be­tween 8.5 and 21 cen­time­ters long. ("The En­cy­clo­pe­dia of Mam­mals", 2001; Huff­man, 2004)

Young yel­low-backed duik­ers are born a dark brown color with spot­ted flanks and red un­der­sides. These cryp­tic col­ors help them re­main hid­den from preda­tors in the for­est. ("The En­cy­clo­pe­dia of Mam­mals", 2001; Huff­man, 2004)

Yel­low-backed duik­ers have unique scent glands lo­cated pos­te­rior to each eye. Un­like other an­te­lope species, these glands se­crete from a group­ing of pores, not from a soli­tary large open­ing. These scent glands are used to mark ter­ri­to­r­ial bound­aries. Yel­low-backed duik­ers are built for life in dense veg­e­ta­tion. The body is arched, with short forelegs and longer hindlegs for manu­ver­abil­ity. ("The En­cy­clo­pe­dia of Mam­mals", 2001; Huff­man, 2004)

Yel­low-backed duik­ers are one of the largest species of for­est duik­ers, rang­ing from 45 to 80 kilo­grams in the wild. The body is 115 to 145 cen­time­ters in length, with a short tail mea­sur­ing 11 to 18 cen­time­ters. Yel­low-backed duik­ers have the largest brain size rel­a­tive to body size than any other an­te­lope species. ("The En­cy­clo­pe­dia of Mam­mals", 2001)

• Other Physical Features
• endothermic
• homoiothermic
• bilateral symmetry

• Sexual Dimorphism
• female larger
• ornamentation

• Range mass

  45 to 80 kg

  99.12 to 176.21 lb

• Range length

  115 to 145 cm

  45.28 to 57.09 in

Re­pro­duc­tion

Yel­low-backed duiker mat­ing pairs have been ob­served lick­ing and nib­bling each other so­cially. This be­hav­ior is also viewed be­tween moth­ers and calves. Adult duik­ers so­cially rub their pre­or­bital scent glands on other adults bod­ies and legs. Duiker mates also press these scent glands to­gether as a pos­si­ble sign of pair bond­ing. It is thought that fe­males de­fend ter­ri­to­ries that they share with males. How­ever, the pair bond may be fairly tran­si­tory. (Estes, 1991)

• Mating System
• monogamous

In cap­tiv­ity, yel­low-backed duik­ers go into es­trus once per month through­out the year, last­ing 2 to 3 days. Ges­ta­tion is ap­prox­i­mately 7 months, after which fe­males give birth to one calf. Oc­ca­sion­aly, 2 calves are born. Fe­males may breed twice each year. Young yel­low-backed duik­ers stay hid­den for 1 to 2 weeks in the for­est. One male calf in cap­tiv­ity at the Los An­ge­les Zoo was weaned after 95 days, al­though oth­ers have been recorded at about 5 months. Fe­males are sex­u­ally ma­ture at 9 to 12 months of age, while males reach ma­tu­rity at 12 to 18 months. (Barnes, et al., 2002; Huff­man, 2004)

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

• Breeding interval

  Yellow-backed duikers may breed twice each year.

• Breeding season

  Yellow-backed duikers can breed throughout the year.

• Range number of offspring

  1 to 2

• Average number of offspring

  1

• Average number of offspring

  1

  AnAge

• Range gestation period

  4 (low) months

• Average gestation period

  7 months

• Range weaning age

  3.17 to 5 months

• Range age at sexual or reproductive maturity (female)

  9 to 12 months

• Range age at sexual or reproductive maturity (male)

  12 to 18 months

Young are weaned after ap­prox­i­mately 5 months. It is un­known how long young stay with the mother. The young re­main hid­den for their first week of life, after which they begin to emerge from hid­ing to browse on veg­e­ta­tion. (Huff­man, 2004)

• Parental Investment
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
• extended period of juvenile learning

Lifes­pan/Longevity

In cap­tiv­ity, other species of Cephalo­phus can live 10 to 15 years. In the wild duik­ers can live 10 to 12 years. ("The En­cy­clo­pe­dia of Mam­mals", 2001; Huff­man, 2004)

• Range lifespan
  Status: wild

  10 to 12 years

• Average lifespan
  Status: captivity

  22.5 years

  AnAge

Be­hav­ior

Yel­low-backed duik­ers are a non-gre­gar­i­ous species. They rest alone dur­ing the day in "forms" - reg­u­larly used rest­ing places under fallen trees, in dense un­der­growth, or in root forms - and for­age at night. Males and fe­males share ter­ri­to­ries and loosely as­so­ci­ate for mat­ing. Duik­ers are ex­cep­tion­ally sus­cep­ti­ble to stress in cap­tiv­ity (cap­ture my­opa­thy). ("The En­cy­clo­pe­dia of Mam­mals", 2001; Barnes, et al., 2002; Kranz and Lump­kin, 1982)

Yel­low-backed duik­ers have also been seen rest­ing on the peaks of ter­mite mounds in order to gain a van­tage point. This and the fact that some fe­males have been ob­served with bro­ken horns, sug­gests that duik­ers ac­tively de­fend ter­ri­to­ries. Ter­ri­to­r­ial bound­aries are also marked with the max­il­lary glands. (Huff­man, 2004)

• Key Behaviors
• terricolous
• nocturnal
• motile
• sedentary
• solitary
• territorial

Home Range

Home range sizes are not known.

Com­mu­ni­ca­tion and Per­cep­tion

Yel­low-backed duik­ers com­mu­ni­cate with unique scent glands an­te­rior to the eyes. These max­il­lary glands are made of con­nec­tive tis­sues that sur­rounds 2 to 3 se­cre­tory lay­ers form­ing hair­less slits. The pres­ence of these glands cause the cheeks to swell. Duik­ers also have scent glands be­hind each hoof. Gland scents are used to com­mu­ni­cate ter­ri­to­r­ial bound­aries, re­pro­duc­tive sta­tus, and as a way of ce­ment­ing so­cial bonds. Yel­low-backed duik­ers also com­mu­ni­cate through grunts and shrill bleats. When alarmed, these duik­ers emit a shrill whis­tle, erect their dor­sal crest, and flee. ("The En­cy­clo­pe­dia of Mam­mals", 2001; Estes, 1991; Huff­man, 2004)

• Communication Channels
• visual
• acoustic
• chemical

• Other Communication Modes
• scent marks

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

Yel­low-backed duik­ers are se­lec­tive-for­ag­ing fru­gi­vores. Typ­i­cal diets are low in fiber. Starches are fer­mented quickly, with rapid pas­sage through the di­ges­tive tract. Along with fruit, yel­low-backed duik­ers eat leaves, seeds, buds, bark, and shoots. Four yel­low-backed duik­ers in the wild ate 71.3% fruit mat­ter and 28.6% dry weight. Oc­ca­sion­ally, these for­est an­telopes will kill and eat small an­i­mals, such as birds. Of the 28.6% dry weight, 0.1% was an­i­mal mat­ter. (Barnes, et al., 2002; Kranz and Lump­kin, 1982)

Yel­low-backed duik­ers spe­cial­ize on eat­ing fallen fruits and can con­sume fruits or seeds that are too large or hard for pri­mates and other fru­gi­vores to eat. Duiker cheek teeth are spe­cial­ized for chew­ing tough bark and roots. A long pointed tongue and mo­bile lips allow fo­liage to be eas­ily ob­tained and ma­nip­u­lated. Duik­ers search the ground for food using their hooves and snouts to dig. The large size of yel­low-backed duik­ers forces them to for­age al­most con­stantly. (Estes, 1991)

• Primary Diet
• herbivore
  • frugivore

• Animal Foods
• birds
• mammals

• Plant Foods
• leaves
• roots and tubers
• wood, bark, or stems
• seeds, grains, and nuts
• fruit

Pre­da­tion

Preda­tors of yel­low-back duik­ers in­clude African hunt­ing dogs, lions, and leop­ards. When they are alarmed, the typ­i­cal re­sop­nse is for the yel­low rump hairs to stand erect. A shrill call may be emit­ted be­fore dash­ing into the cover of un­der­brush habi­tat. Young duik­ers stay hid­den in the for­est for more than 7 days to evade preda­tors be­fore be­gin­ning to ven­ture out. When threat­ened, the re­sponse is to flee into dense for­est. Their habit of seem­ing to dive into the un­der­growth gives them their com­mon name, duiker, which is de­rived from Afrikaans for "div­ing buck." Yel­low-backed duik­ers also hold their yel­low rump hairs erect when ag­i­tated. (Huff­man, 2004; Kranz and Lump­kin, 1982; Huff­man, 2004; Kranz and Lump­kin, 1982)

• Anti-predator Adaptations
• cryptic

• Known Predators

  • lions (Panthera leo)
  • African wild dogs (Lycaon pictus)
  • leopards (Panthera pardus)
  • ball pythons (Python regius)
  • African civets (Civettictis civetta)
  • crocodiles (Crocodilus)

Ecosys­tem Roles

It is un­known how im­por­tant for­est duik­ers are in seed dis­per­sal in African forests. Duik­ers have been ob­served spit­ting out di­gested seeds after ru­mi­na­tion. Some seeds re­main in­tact and are dis­persed in this way. Duik­ers act as preda­tors on other seeds by dam­ag­ing them dur­ing di­ges­tion. Larger mam­mals also prey on adult and young duik­ers. (Feer, 1995)

Three new species of Coc­cidia have been found in for­est duik­ers. These par­a­sites were not found in any other wild or do­mes­tic African ru­mi­nant. Coc­cidia was doc­u­mented in Philan­tomba mon­ti­cola, Cephalo­phus dor­salis, and Cephalo­phus ni­grifrons. Cephalo­phus maxwelli was dis­cov­ered with the par­a­site Se­leno­mas ru­mi­nan­ticum. It is pos­si­ble that Coc­cidia species will be dis­cov­ered in C. sil­vicul­tor. (Her­man and Sayama, 1951; Pampiglione, et al., 1973)

• Ecosystem Impact
• disperses seeds

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Cephalo­phus sil­vicul­tor is an im­por­tant form of meat and money for peo­ple liv­ing in cen­tral and west­ern Africa. In many in­stances, yel­low-backed duiker meat is nec­es­sary bush­meat for local sur­vival. They are hunted with a va­ri­ety of meth­ods, in­clud­ing snares, shot­guns, or net­ting. At night, duik­ers are eas­ily shot be­cause they stand still when light is shone on them. (New­ing, 2001)

• Positive Impacts
• food
• body parts are source of valuable material

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There are no known ad­verse ef­fects of Cephalo­phus sil­vicul­tor on hu­mans.

Con­ser­va­tion Sta­tus

Human ex­pan­sion has caused a change in some African habi­tats from ma­ture forests to clear­ings for agri­cul­ture, di­rectly im­pact­ing yel­low-duiler pop­u­la­tions, which rely on forested habi­tat. Yel­low-backed duik­ers re­quire dense for­est cover to hide, be­cause of their large size. Smaller duik­ers, such as blue duik­ers (Philan­tomba mon­ti­cola), can con­ceal them­selves in the more open habi­tats where they live. (Estes, 1991; Wilkie and Finn, 1990)

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Federal List

  No special status

• CITES

  Appendix II

Other Com­ments

Cephalo­phus sil­vicul­tor is con­sid­ered one of the most evo­lu­tion­ar­ily an­ces­tral (prim­i­tive) African an­telopes that ex­ists today. ("The En­cy­clo­pe­dia of Mam­mals", 2001)

The name "duiker" comes from an African word mean­ing "diver". This refers to their ten­dency to run and hide in for­est cover when threat­ened. Cephalo­phus sil­vicul­tor can be bro­ken into its Greek roots. "Kephale" refers to the head, and "lo­phus" to a crest, both are as­so­ci­ated with a tuft of fur on the yel­low-backed duik­ers head. "Silva" means woods or for­est, and "cul­tor" im­plies a farmer or in­hab­i­tant, both these terms imply the an­i­mal lives in the for­est. (Huff­man, 2004)

Con­trib­u­tors

Tanya Dewey (ed­i­tor), An­i­mal Di­ver­sity Web.

Kristina De­Witt (au­thor), Uni­ver­sity of Wis­con­sin-Stevens Point, Chris Yahnke (ed­i­tor, in­struc­tor), Uni­ver­sity of Wis­con­sin-Stevens Point.

Ref­er­ences

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2001. The En­cy­clo­pe­dia of Mam­mals. Pp. "542-545" in D Mac­Don­ald, ed. Barnes and Noble Inc.

Barnes, R., K. Greene, J. Hol­land, M. Lamm. 2002. Man­age­ment and Hus­bandry of Duik­ers at the Los An­ge­les Zoo. Zoo Bi­ol­ogy, 21/2: "107-121".

Estes, R. 1991. The Be­hav­ior Guide to African Mam­mals In­clud­ing Hoofed Mam­mals, Car­ni­vores, Pri­mates. Uni­ver­sity of Cal­i­for­nia Press. Ac­cessed No­vem­ber 29, 2006 at http://​books.​google.​com/​books?​hl=en&​lr=&​id=g977LsZHpcsC&​oi=fnd&​pg=PR11&​sig=73mHRqw7GQTw93UUcVXIIx7s6jM&​dq=duiker+mating+systems&​prev=http://​scholar.​google.​com/​scholar%3Fq%3Dduiker%2Bmating%2Bsystems%26hl%3Den%26lr%3D#​PRA1-PA90000,M1.

Feer, F. 1995. Seed Dis­per­sal in African For­est Ru­mi­nants. Jour­nal of Trop­i­cal Ecol­ogy, 11: 687-689. Ac­cessed De­cem­ber 01, 2006 at http://​www.​jstor.​org/​view/​02664674/​di008869/​00p0125a/​0?​frame=frame&​userID=8fec23ca@​uwsp.​edu/​01cce4405f00501b3ca63&​dpi=3&​config=jstor.

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Her­man, C., K. Sayama. 1951. Fur­ther Notes on Se­lenomonas from Cal­i­forn­ian Mam­mals. Trans­ac­tions of the Amer­i­can Mi­cro­scop­i­cal So­ci­ety: 185-187. Ac­cessed No­vem­ber 29, 2006 at http://​www.​jstor.​org/​view/​00030023/​sp050176/​05x0019s/​0?​frame=noframe&​userID=8fec23ca@​uwsp.​edu/​01cc99331300501b33b1a&​dpi=3&​config=jstor.

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Kranz, K., S. Lump­kin. 1982. Notes on the Yel­low-backed duiker Cephalo­phus sylvicul­tor in cap­tiv­ity with com­ments on its nat­ural his­tory. In­ter­na­tional Zoo Year­book, 22: 232-240.

New­ing, H. 2001. Bush­meat Hunt­ing and Man­age­ment: im­pli­ca­tions of duiker ecol­ogy and in­ter­spe­cific com­pe­ti­tion. Bio­di­ver­sity and Con­ser­va­tion, 10: "99-118".

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