Olive colobus

Last updated

Olive colobus [1]
Procolobus verus.jpg
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Haplorhini
Infraorder: Simiiformes
Family: Cercopithecidae
Subfamily: Colobinae
Tribe: Colobini
Genus: Procolobus
Rochebrune, 1877
Species:
P. verus
Binomial name
Procolobus verus
(van Beneden, 1838)
Olive Colobus area.png
Olive colobus range

The olive colobus monkey (Procolobus verus), also known as the green colobus or Van Beneden's colobus, is a species of primate in the family Cercopithecidae. Its English name refers to its dull olive upperparts. [3] It is the smallest example of all colobine monkeys and is rarely observed in its natural habitat because of its cryptic coloration and secretive nature. [4] It is found in the rain forests of West Africa, ranging from southern Sierra Leone to Nigeria. [2] The IUCN Red List classifies the olive colobus as vulnerable [2] (previously near threatened), with the cause of its decline attributed to habitat loss and hunting. [2] Though much of the land within the range of the olive colobus has been affected by human activities, it retains its ability to thrive in small degraded forest fragments. [2]

Contents

Description

Procolobus verus is a small-bodied mammal with an average body weight of 4.6 kilograms for males and 4.1 kilograms for females. [4] The olive colobus are greenish-brown in color with the hairs transitioning from greenish-yellow at the root, and becoming darker towards the tip. [5] The under side of the olive colobus is lighter in color and the hairs found on the face are stiff and dark. [5] Their coloration allows them to stay camouflaged within the trees reducing the risk of predation. Like all colobine monkeys, [6] olive colobuses have a unique feature in that their thumb is severely reduced on their forefeet, while the hind feet retain five digits. [5] The feet of the olive colobus are also abnormally large compared to other African colobine species. [7]

Diet

The natural habitat of the olive colobus includes second growth within tall forests, palm forests and swamps, where they feed in the lower and middle vegetation strata. [2] The olive colobus is mainly folivorous, although it may consume fruits and seeds when available. [8] The diet consists primarily of young leaves, and they tend to avoid mature leaf parts altogether. This is related to the fact that it is a forestomach fermenter with a small body size, which requires it to obtain a very high quality diet. [8] The fact that olive colobus monkeys utilize this type of fermentation also relates to their lack of fruit consumption, because fruits that contain high levels of acid can overly lower the pH of the stomach, causing negative and sometimes lethal effects on microorganisms living within it. [8]

Behavior

The olive colobus monkey is a very cryptic and shy animal, which can make the observation and understanding of its behavior difficult. What is known about interactions between olive colobus monkeys and other related species shows that their social structure is very complex. Olive colobus monkeys are found in small groups containing multiple breeding males, several females, and their infants. [9] Though found in groups of only a few individuals, olive colobus monkeys are almost always seen in association with other monkeys, particularly the Diana monkey, Cercopithecus diana. [9] There have been many suggestions as to how this relationship benefits the olive colobus, such as reducing the risk of predation. [9] A piece of evidence that gives support to this idea is the willingness of the olive colobus to travel to higher altitudes in the tree tops to feed when other species are nearby. [2]

In addition to serving as a means of predator avoidance, the close association with Diana monkeys is a mechanism used by male olive colobus monkeys to obtain new female mates. The olive colobus mating system is unique in that unlike many species living in small groups, there is no evidence of male monopolization over females. It has been proposed that females use aspects of their reproductive biology(long receptive periods, promiscuous mating, and mating overlap among females) along with mating behaviors to limit the monopolization of males in a group. Benefits to the avoidance of male monopolization include direct or indirect female mate choice, decreasing the risk of infanticide, and increased paternal care for offspring. [9]

Conservation

The olive colobus monkey is very susceptible to habitat loss due to increased encroachment of hunters and farmers on both protected and unprotected lands. In order to ensure that this threatened species is protected, the olive colobus has been listed under Appendix II of CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) and as a Class A species under the African Convention on the Conservation of Nature and Natural Resources, which monitor the international trade of species and their status in the environment. [2] The olive colobus is also covered in many protected areas including Taï National Park on the Ivory Coast of West Africa, which was declared a Forest and Wildlife Refuge in 1926 and accepted as a biosphere reserve in 1982. [10] The park has a total area of 330,000 hectares, plus a 20,000-hectare buffer zone, where new plantations and settlement are prohibited. [11]

Though efforts have been established in order to protect the olive colobus monkey and its habitat, illegal farming and hunting are still a fundamental threat to this species' survival. To ensure that the olive colobus will thrive in the future, stricter enforcement of laws and regulations should be implemented, as well as the development of educational and public awareness plans. The olive colobus will also benefit from further study and observation. [11]

Related Research Articles

<span class="mw-page-title-main">Black-and-white colobus</span> Genus of Old World monkeys

Black-and-white colobuses are Old World monkeys of the genus Colobus, native to Africa. They are closely related to the red colobus monkeys of genus Piliocolobus. There are five species of this monkey, and at least eight subspecies. They are generally found in high-density forests where they forage on leaves, flowers and fruit. Social groups of colobus are diverse, varying from group to group. Resident-egalitarian and allomothering relationships have been observed among the female population. Complex behaviours have also been observed in this species, including greeting rituals and varying group sleeping patterns. Colobi play a significant role in seed dispersal.

<span class="mw-page-title-main">Old World monkey</span> Family of mammals

Old World monkey is the common English name for a family of primates known taxonomically as the Cercopithecidae. Twenty-four genera and 138 species are recognized, making it the largest primate family. Old World monkey genera include baboons, red colobus and macaques. Common names for other Old World monkeys include the talapoin, guenon, colobus, douc, vervet, gelada, mangabey, langur, mandrill, surili (Presbytis), patas, and proboscis monkey. Phylogenetically, they are more closely related to apes than to New World monkeys. They diverged from a common ancestor of New World monkeys around 45 to 55 million years ago.

<span class="mw-page-title-main">Diana monkey</span> Species of Old World monkey

The Diana monkey is an Old World monkey found in the high canopy forests in Sierra Leone, Liberia, and western Côte d’Ivoire. Named for its white brow which is said to resemble the bow of the Roman goddess Diana, this black-grey guenon has a white throat, crescent-shaped browband, ruff and beard.

<span class="mw-page-title-main">Zanzibar red colobus</span> Species of Old World monkey

The Zanzibar red colobus is a species of red colobus monkey endemic to Unguja, the main island of the Zanzibar Archipelago, off the coast of Tanzania. It is also known as Kirk's red colobus after Sir John Kirk, the British Resident of Zanzibar who first brought it to the attention of zoological science. It is now classified as an endangered species and in the mid-1990s was adopted as the flagship species for conservation in Zanzibar. The population is still decreasing, and conservationists are attempting to work with the local government to devise a proper, effective strategy to protect the population and habitat. Challenges include the species' habitat, which is limited to the archipelago. The species has been reclassified three times; it was previously in the genus Colobus, then in the genus Procolobus, and later in the genus Piliocolobus.

<span class="mw-page-title-main">Colobinae</span> Subfamily of Old World monkeys

The Colobinae or leaf-eating monkeys are a subfamily of the Old World monkey family that includes 61 species in 11 genera, including the black-and-white colobus, the large-nosed proboscis monkey, and the gray langurs. Some classifications split the colobine monkeys into two tribes, while others split them into three groups. Both classifications put the three African genera Colobus, Piliocolobus, and Procolobus in one group; these genera are distinct in that they have stub thumbs. The various Asian genera are placed into another one or two groups. Analysis of mtDNA confirms the Asian species form two distinct groups, one of langurs and the other of the "odd-nosed" species, but are inconsistent as to the relationships of the gray langurs; some studies suggest that the gray langurs are not closely related to either of these groups, while others place them firmly within the langur group.

<span class="mw-page-title-main">King colobus</span> Species of Old World monkey

The king colobus, also known as the western black-and-white colobus, is a species of Old World monkey, found in lowland and mountain rainforests in a region stretching from Senegal, through Guinea-Bissau, Guinea, Sierra Leone and Liberia to the Ivory Coast. One of five members of the genus Colobus, the black-and-white colobuses, the king colobus is the westernmost species of the group on the continent of Africa. It eats mainly leaves, but also fruits and flowers. Though it is arboreal, it eats primarily on the ground. It lives in small groups consisting of 3 to 4 females and 1 to 3 males, plus their young. These groups maintain distance from one another through territorial calling.

<span class="mw-page-title-main">Sooty mangabey</span> Species of mammal

The sooty mangabey is an Old World monkey found in forests from Senegal in a margin along the coast down to the Ivory Coast.

<span class="mw-page-title-main">Kibale National Park</span> National park in Uganda

Kibale National Park is a national park in western Uganda, protecting moist evergreen rainforest. It is 766 square kilometres (296 sq mi) in size and ranges between 1,100 metres (3,600 ft) and 1,600 metres (5,200 ft) in elevation. Despite encompassing primarily moist evergreen forest, it contains a diverse array of landscapes. Kibale is one of the last remaining expanses to contain both lowland and montane forests. In eastern Africa, it sustains the last significant expanse of pre-montane forest.

<span class="mw-page-title-main">Mantled guereza</span> Species of mammal

The mantled guereza, also known simply as the guereza, the eastern black-and-white colobus, or the Abyssinian black-and-white colobus, is a black-and-white colobus, a type of Old World monkey. It is native to much of west central and east Africa, including Cameroon, Equatorial Guinea, Nigeria, Ethiopia, Kenya, Tanzania, Uganda and Chad. The species consists of several subspecies that differ in appearance. It has a distinctive appearance, which is alluded to in its name; the long white fringes of hair that run along each side of its black trunk are known as a mantle. Its face is framed with white hair and it has a large white tail tuft.

<span class="mw-page-title-main">Red colobus</span> Genus of Old World monkeys

Red colobuses are Old World monkeys of the genus Piliocolobus. It was formerly considered a subgenus within the genus Procolobus, which is now restricted to the olive colobus. They are closely related to the black-and-white colobus monkeys, and some species are often found in groups with the blue monkey. The western red colobus is frequently hunted by the common chimpanzee.

<span class="mw-page-title-main">Miss Waldron's red colobus</span> Species of Old World monkey

Miss Waldron's red colobus is a species of the red colobus native to West Africa. It had previously been described as a subspecies of the western red colobus, P. badius. It has not been officially sighted since 1978 and was considered extinct in 2000. However, new evidence suggests that a very small number of these monkeys may be living in the southeast corner of Côte d'Ivoire. The IUCN Red List notes Miss Waldron's red colobus as critically endangered.

<span class="mw-page-title-main">Western red colobus</span> Species of Old World monkey

The western red colobus, also known as the bay red colobus, rust red colobus or Upper Guinea red colobus, is a species of Old World monkey in West African forests from Senegal to Ghana. All other species of red colobuses have formerly been considered subspecies of P. badius. It is often hunted by the common chimpanzee. In 1994, western red colobus monkeys infected many chimpanzees with Ebola virus when the chimpanzees hunted the monkeys as prey.

<span class="mw-page-title-main">Black colobus</span> Species of Old World monkey

The black colobus, or satanic black colobus, is a species of Old World monkey belonging to the genus Colobus. The species is found in a small area of western central Africa. Black colobuses are large, completely covered with black fur, and like all other Colobus monkeys, do not have a thumb. The species has faced large declines in population due to habitat destruction and hunting by humans, and was consequently listed as Vulnerable on the IUCN Red List in 1994.

<span class="mw-page-title-main">Ursine colobus</span> Species of Old World monkey

The ursine colobus, also known as the white-thighed colobus, Geoffroy's black-and-white colobus, or the white-thighed black-and-white colobus, is a species of primate in the family Cercopithecidae.

<span class="mw-page-title-main">Pennant's colobus</span> Species of Old World monkey

Pennant's colobus or Pennant's red colobus is a species of tree-dwelling primate in the family Cercopithecidae. It is endemic to tropical Central Africa. Three subspecies have traditionally been recognised but its distribution is peculiarly disjunct and has been considered a biogeographical puzzle, with one population on the island of Bioko, a second in the Niger River Delta in southern Nigeria, and a third in east-central Republic of Congo. It is found in rainforests and marshy forests. It is threatened by habitat loss and hunting for bushmeat.

<span class="mw-page-title-main">Tana River red colobus</span> Species of Old World monkey

The Tana River red colobus, also called the eastern red colobus, is a highly endangered species of primate in the family Cercopithecidae. It is endemic to a narrow zone of gallery forest near the Tana River in southeastern Kenya.

<span class="mw-page-title-main">Gabon talapoin</span> Species of Old World monkey

The Gabon talapoin, also known as the northern talapoin, is a small species of African monkey native to riparian habitats in Cameroon, Equatorial Guinea, Gabon, the western Republic of the Congo and the far western Democratic Republic of Congo. It may have been introduced to Bioko and the Canary Islands. Classified in the genus Miopithecus, it was given the name Miopithecus ogouensis, based on the River Ogooué, distinguishing it from the other species, the Angolan talapoin, also known as Miopithecus talapoin.

<span class="mw-page-title-main">Thollon's red colobus</span> Species of Old World monkey

Thollon's red colobus, also known as the Tshuapa red colobus, is a species of red colobus monkey from the Democratic Republic of the Congo and lower Republic of the Congo. It is found south of Congo River and west of Lomami River. It had once been considered a subspecies of the P. badius. It was recognised as a distinct species by Dandelot in 1974, and this was followed by Groves in 2001, while others have suggested it should be considered a subspecies of P. rufomitratus.

<span class="mw-page-title-main">Ugandan red colobus</span> Species of Old World monkey

The Ugandan red colobus or ashy red colobus is an endangered species of red colobus monkey, recognised as a distinct species since 2001. There is disagreement however over taxonomy with many considering the Ugandan red colobus to be a subspecies. The Ugandan red colobus is an Old World monkey which is found in 5 different locations across Uganda and Tanzania.

<span class="mw-page-title-main">Niger Delta red colobus</span> Species of Old World monkey

The Niger Delta red colobus is a critically endangered species of colobus monkey endemic to the western part of the Niger Delta. It is threatened by hunting and habitat loss.

References

  1. Groves, C. P. (2005). Wilson, D. E.; Reeder, D. M. (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press. pp. 169, 172–73. ISBN   0-801-88221-4. OCLC   62265494.
  2. 1 2 3 4 5 6 7 8 Oates, J.F.; Gonedelé Bi, S.; Ikemeh, R.; Koné, I.; McGraw, S.; Nobimè, G.; Osei, D.; Wiafe, E. (2020). "Procolobus verus". IUCN Red List of Threatened Species . 2020: e.T18245A166610679. doi: 10.2305/IUCN.UK.2020-1.RLTS.T18245A166610679.en . Retrieved 12 November 2021.
  3. Kingdon, J. (1997). The Kingdon Guide to African Mammals. London: Academic Press Limited. ISBN   0-12-408355-2.
  4. 1 2 Oates, J.F. (1988). "The Diet of the Olive Colobus Monkey, Procolobus verus, in Sierra Leone". International Journal of Primatology. 9 (5): 457–478. doi:10.1007/BF02736220. S2CID   12643053.
  5. 1 2 3 Osman Hill, W.C. (1952). "The External and Visceral Anatomy of the Olive Colobus Monkey (Procolobus verus)". Proceedings of the Zoological Society of London. 122 (1): 127–186. doi:10.1111/j.1469-7998.1952.tb06315.x.
  6. Frost, S.R.; Gilbert, C.C.; et al. (May 2015). "The hand of Cercopithecoides williamsi (Mammalia, Primates): earliest evidence for thumb reduction among colobine monkeys". PLOS ONE. 10 (5): e0125030. Bibcode:2015PLoSO..1025030F. doi: 10.1371/journal.pone.0125030 . PMC   4439063 . PMID   25993410.
  7. McGraw, W.S.; Zuberbühler, K. (2007). "The Monkeys of the Taï Forest: an Introduction". In McGraw, W.S.; Zuberbühler, K.; Nöe, R. (eds.). Monkeys of the Taï Forest: an African Primate Community. Cambridge University Press. pp. 1–48. doi:10.1017/CBO9780511542121.002. ISBN   9780511542121.
  8. 1 2 3 Davies, A.G.; Oates, J. F.; Dasilva, G.L. (1999). "Patterns of Frugivory in Three West African Colobine Monkeys". International Journal of Primatology. 20 (3): 327–357. doi:10.1023/A:1020596503533. S2CID   30522803.
  9. 1 2 3 4 Korstjens, A.H.; Nöe, R. (2004). "Mating System of an Exceptional Primate, the Olive Colobus (Procolobus verus)". American Journal of Primatology. 62 (4): 261–273. doi:10.1002/ajp.20020. PMID   15085531. S2CID   23397539.
  10. "Taï National Park". UNESCO World Heritage Centre. Retrieved 7 November 2011.
  11. 1 2 McGinley, Mark (14 October 2008). "Taï National Park, Côte d'Ivoire". The Encyclopedia of Earth. Retrieved 7 November 2011.