{{short description|Species of mammal}} {{Good article}} {{Speciesbox |name = Mantled guereza<ref name="MSW">{{MSW3 Groves | pages = 168 | id = 12100605}}</ref> |image = Mantled Guereza.jpg |image_caption = Male at the Henry Doorly Zoo |image2 = Mantelaffe-mit-Baby-Zoo-Muenster.jpg |image2_caption = Female with infant at Münster Zoo |status = LC |status_system = IUCN3.1 |status_ref = <ref name="iucn status 11 November 2021">{{cite iucn |author=de Jong, Y.A. |author2=Butynski, T.M. |author3=Oates, J.F. |date=2019 |title=''Colobus guereza'' |volume=2019 |article-number=e.T5143A17944705 |doi=10.2305/IUCN.UK.2019-3.RLTS.T5143A17944705.en |access-date=11 November 2021}}</ref> |genus = Colobus |species = guereza |authority = Rüppell, 1835 |range_map = Mantled_Guereza_area.png |range_map_caption = Mantled guereza range }}
The '''mantled guereza''' ('''''Colobus 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.
The mantled guereza is diurnal and arboreal, found in both deciduous and evergreen forests. It is an adaptable species that can cope with habitat disturbance and prefers secondary forest close to rivers or lakes. Although previously thought to eat only leaves, it also eats seeds, fruits, and arthropods. It is able to digest plant material with a high fibre content with its specialised stomach and may only eat from a few plant species at a time. It is preyed on by birds of prey and some mammals, such as the common chimpanzee and the leopard.
The mantled guereza lives in social groups of three to fifteen individuals. These groups normally include a dominant male, several females, and the offspring of the females. It has a polygynous mating system and copulation is initiated with vocal communication.<ref>{{Cite web |last=Kim |first=Kenneth |date=June 21, 2024 |title=Colobus guereza |url=https://animaldiversity.org/accounts/Colobus_guereza/ |access-date=June 21, 2024 |website=University of Michigan Museum of Zoology's Animal Diversity Web}}</ref> After a gestation period of just over five months, infants are born with pink skin and white fur, which darkens to the adult coloration by three to four months. The mantled guereza is well known for its dawn chorus, the males' "roar" is a method of long-distance communication that reinforces territorial boundaries. It also makes other vocalization and uses body postures, movements, and facial expressions to communicate.
The mantled guereza is listed as Least Concern by the International Union for Conservation of Nature (IUCN) because it is widespread – although it is locally threatened in some areas, the decline is not great enough to list it in a higher category of threat. However, one subspecies found in Kenya is listed as Endangered. It can survive well in degraded forests and in some areas it is more common in logged areas than unlogged ones. The mantled guereza is also threatened by hunting for bushmeat and for its skin.
==Etymology== thumb|Close-up of face & head The mantled guereza has many alternative common names including the guereza, the eastern black-and-white colobus, the magistrate colobus,<ref name="iucn status 11 November 2021" /> or the Abyssinian black-and-white colobus.<ref name="Wolfheim1983">{{Cite book | last = Wolfheim | first = J. H. | year = 1983 | title = Primates Of The World: Distribution, Abundance And Conservation | publisher = Routledge | isbn = 978-3-7186-0190-5}}</ref> The name "mantled" refers to its mantle, the long silky white fringes of hair that run along its body and "guereza" is the native name of the monkey in Ethiopia.<ref name="Merriam-Webster">{{Cite dictionary | title = Guereza | encyclopedia = Merriam-Webster dictionary | publisher = Merriam-Webster | url = http://www.merriam-webster.com/dictionary/guereza | access-date = 2 April 2013}}</ref> The scientific name ''Colobus'' derives from Greek ''kolobus'' meaning "mutilated" which refers to its lack of thumbs.<ref name="Grzimek">{{Cite book | title = Grzimek's Animal Life Encyclopedia: Mammals I-IV | year = 1972 | volume = 10 | first = B. | last = Grzimek | publisher = Van Nostrand Reinhold Co. | page = 464}}</ref>
==Taxonomic classification== The mantled guereza was first classified by Eduard Rüppell, a German naturalist and explorer, during his trip to Abyssinia between 1830 and 1834.<ref name="BeolensWatkinsGrayson2009">{{Cite book | title = The Eponym Dictionary of Mammals | url = https://archive.org/details/eponymdictionary00beol | url-access = limited | first1 = B. | last1 = Beolens | first2 = M. | last2 = Watkins | first3 = M. | last3 = Grayson | publisher = JHU Press | year = 2009 | isbn = 978-0-8018-9533-3 | page = [https://archive.org/details/eponymdictionary00beol/page/n369 353]}}</ref> He wrote about the species in ''Neue Wirbelthiere con Abyssinien, Saengthiere'' in 1835.<ref name="Allen1851">{{Cite book | title = A Catalogue of the Mammalia in the Museum of the Hon. East-India Company | publisher = Allen | year = 1851 | page = 16 | url = https://books.google.com/books?id=S4U-AAAAcAAJ&pg=PA16 | type = Google eBook}}</ref> It was first seen in Europe in 1890 in Berlin Zoological Garden when three individuals were purchased from a dealer from Massawa, Eritrea.<ref name="PopularScience">{{Cite journal | title = Two rare monkeys | last = Heck | first = L. | journal = The Popular Science Monthly | year = 1892 | volume = 41 | issue = 22 | issn = 0161-7370 | page = 393 | url = https://books.google.com/books?id=nSADAAAAMBAJ&pg=PA393 | publisher = Bonnier Corporation }}</ref>
thumb|Distribution map of subspecies of Mantled guereza The mantled guereza is in the Colobinae subfamily, also known as the leaf-eating monkeys, a group of Old World monkeys from Asia and Africa. This subfamily is split into three groups, the colobus monkeys of Africa, of which the mantled guereza is a part, the langurs, or leaf monkeys, of Asia, and an "odd-nosed" group. The African colobus monkeys are divided again by distinctions in color, behavior, and ecology. The three genera are the black-and-white colobi, the red colobi, and the olive colobi. There are three black-and-white colobi: the mantled guereza, ''Colobus guereza'', the king colobus, ''C. polykomos'', and the Angola colobus, ''C. angolensis''.<ref name="Fleagle1998">{{Cite book | last = Fleagle | first = J. G. | publisher = Academic Press | title = Primate Adaptation and Evolution | edition = 2nd | year = 1998 | isbn = 978-0-12-260341-9 | pages = [https://archive.org/details/primateadaptatio0000flea/page/207 207–209] | url = https://archive.org/details/primateadaptatio0000flea/page/207 }}</ref> Groves lists seven subspecies of mantled guereza in Mammal Species of the World (MSW) (2005).<ref name="MSW" /> The validity of the Djaffa Mountain guereza, ''C. g. gallarum'', is uncertain, although not listed by Groves in MSW, it is recognised in his 2007 Colobinae review paper,<ref name="Groves2007">{{Cite journal | last = Groves | first = C. | author-link = Colin Groves | year = 2007 | title = The taxonomic diversity of the Colobinae of Africa | journal = Journal of Anthropological Sciences | volume = 85 | pages = 7–34 | url = http://www.arts.anu.edu.au/grovco/Colobus%20JASs%2007.pdf | archive-url = https://web.archive.org/web/20130419143302/http://arts.anu.edu.au/grovco/Colobus%20JASs%2007.pdf | archive-date = 2013-04-19 }}</ref> and by International Union for Conservation of Nature (IUCN) assessors Gippolliti and Butynski in 2008.<ref name="iucn status 11 November 2021" /> *Western guereza, ''Colobus guereza occidentalis'', occurs from eastern Nigeria, Cameroon, and Gabon at the edge of its western range to South Sudan and Uganda, west of the Nile. *Omo River guereza or Abyssinian black-and-white colobus, ''C. g. guereza'', found in Ethiopia, in the highlands west of the Rift Valley down to the reaches of the Awash River, the Omo River, and in the Blue Nile gorge. *Djaffa Mountains guereza or Neumann's black-and-white colobus, ''C. g. gallarum'', found in the Ethiopian Highlands east of the Rift Valley. *Dodinga Hills guereza, ''C. g. dodingae'', found in the Didinga Hills in South Sudan. *Mau Forest guereza, ''C. g. matschiei'', occurs from western Kenya and Uganda south into northern Tanzania. *Mt Uaraguess guereza or Percival's black-and-white colobus, ''C. g. percivali'', found in the Matthews Range in Kenya. *Eastern black-and-white colobus, ''C. g. kikuyuensis'', occurs in Kenya on the Ngong Escarpment of Mount Kenya and in the Aberdare Range. *Kilimanjaro guereza, ''C. g. caudatus'', found in Tanzania and Kenya in the forests surrounding Mount Kilimanjaro and Mount Meru.
The morphological difference between subspecies is most pronounced between the southeastern Kilimanjaro guereza, ''C. g. caudatus'', and the northwestern western guereza, ''C. g. occidentalis''. The intermediate subspecies show a gradual change between the two.<ref name="Groves2007" /> <gallery mode="packed" heights="130"> File:Eastern black-and-white colobus (Colobus guereza occidentalis).jpg|''C. g. occidentalis''<br />At the Semliki Wildlife Reserve in Uganda File:Eastern black-and-white colobus (Colobus guereza occidentalis) with juvenile.jpg|''C. g. occidentalis'' with juvenile<br />At the Semliki Wildlife Reserve in Uganda File:Eastern black-and-white colobus (Colobus guereza matschiei).jpg|''C. g. matschiei'' with juvenile<br />At the Lake Naivasha in Kenya File:Eastern black-and-white colobus (Colobus guereza matschiei) head.jpg|''C. g. matschiei''<br />At the Lake Naivasha in Kenya File:Abyssinian black-and-white colobus (Colobus guereza guereza) male.jpg|male ''C. g. guereza''<br />At the Amora Gedel Park in Awassa, Ethiopia File:Abyssinian black-and-white colobus (Colobus guereza guereza) male head.jpg|male ''C. g. guereza''<br />At the Amora Gedel Park in Awassa, Ethiopia File:Abyssinian black-and-white colobus (Colobus guereza guereza) juvenile female.jpg|juvenile female ''C. g. guereza''<br />At the Amora Gedel Park in Awassa, Ethiopia </gallery>
==Physical description== thumb|3d model of the skeleton [[File:Colobus guereza 04 MWNH 212.jpg|thumb|A skull at the Museum Wiesbaden in Wiesbaden, Germany]] The mantled guereza has a distinctive pelage, which is mostly black, with long white fringes of silky hair—known as a mantle or ornamentation—along the sides of its body and tail. The bands that make up the mantle start at the shoulders and extend along the back until they connect at the lower torso. The tail is long and ends in a white tuft which varies in how much it covers the tail. These features vary in color among subspecies, for example the tail of ''C. g. guereza'' is gray until the white tail tuft which covers half of its length, while the tail tuft of ''C. g. caudatus'' makes up 80% of the tail. The mantle color ranges from white to cream or yellow. Its face is framed by white hair and it has bushy cheek hairs. The thigh has a white stripe.<ref name="Groves2001">{{Cite book | last = Groves | first = C. | author-link = Colin Groves | year = 2001 | title = Primate Taxonomy | location = Washington DC | publisher = Smithsonian Institution Press}}</ref>
Infants are born with pink skin and white hair. The hair and skin darken as they age and by three to four months they attain adult coloration. Male usually gain their coloration before females.<ref name="Ackerman1991">{{Cite journal | last = Ackerman | first = D. E. | year = 1991 | title = A study of the colobus monkey (''Colobus guereza kikuyuensis'') | journal = Animal Keeper's Forum | volume = 18 | issue = 4 | pages = 164–171}}</ref> The male typically weighs {{Convert|9.3|and|13.5|kg|lb}} and the female weighs between {{Convert|7.8|and|9.2|kg|lb}}. The head and body length averages {{Convert|61.5|cm|in}} for males and {{Convert|57.6|cm|in}} for females. Like most colobi, the mantled guereza has a small thumb that is vestigial.<ref name="Napier1985">{{Cite book | last = Napier | first = P. H. | year = 1985 | title = Catalogue of Primates in the British Museum (Natural History) and Elsewhere in the British Isles, part III: Family Cercopithecidae, Subfamily Colobinae | location = London | publisher = British Museum (Natural History)}}</ref>{{Sfn|Davies|Oates|1994}} There is dentition sexual dimorphism among the subspecies. In some, the males have larger teeth than females, in others the reverse is true, and some have no significant difference.<ref name="HayesFreedmanOxnard1995">{{Cite journal | last1 = Hayes | first1 = V. J. | last2 = Freedman | first2 = L. | last3 = Oxnard | first3 = C. E. | year = 1995 | title = The differential expression of dental sexual dimorphism in subspecies of ''Colobus guereza'' | journal = International Journal of Primatology | volume = 16 | issue = 6 | pages = 971–996 | doi=10.1007/bf02696112 | s2cid = 23753155}}</ref>
==Distribution and habitat== [[File:Colobuses in Murchison Falls National Park.JPG|thumb|right|Mantled guerezas are arboreal and prefer secondary forests.]] The mantled guereza is distributed throughout Equatorial Africa. It ranges from Nigeria and Cameroon in the west to Ethiopia, Kenya, Uganda, and northern Tanzania in the east.<ref name="Groves2001" /><ref name="Napier1985" /> The mantled guereza lives in both deciduous and evergreen forests. It mainly inhabits forest and savannah woodlands and often extend into highland and montane forests.{{Sfn|Oates|1994a|pp=75–128}} It can be found in other forest habitats, both primary and secondary, such as riparian (near fresh or brackish water), gallery, and upland forests. It is particularly common in forests close to rivers and lakes and at high elevations.<ref name="Dunbar1987">{{Cite journal | last = Dunbar | first = R. I. M. | year = 1987 | title = Habitat quality, population dynamics, and group composition in colobus monkeys (''Colobus guereza'') | journal = International Journal of Primatology | volume = 8 | issue = 4 | pages = 299–329 | doi=10.1007/bf02737386 | s2cid = 2006267 }}</ref> It can be found in elevations as high as {{Convert|3300|m|ft}}.<ref name="DunbarDunbar1974">{{Cite journal | last1 = Dunbar | first1 = R. I. M. | last2 = Dunbar | first2 = E. P. | year = 1974 | title = Ecology and population dynamics of ''Colobus guereza'' in Ethiopia | journal = Folia Primatologica | volume = 21 | issue = 3–4 | pages = 188–208 | doi=10.1159/000155600 | pmid = 4214737 }}</ref> This species prefers secondary forests and selects them over old-growth forests if given the choice.<ref name="Lwanga2006">{{Cite journal | last1 = Lwanga | first1 = J. S. | title = Spatial distribution of primates in a mosaic of colonizing and old growth forest at Ngogo, Kibale National Park, Uganda | doi = 10.1007/s10329-005-0173-5 | journal = Primates | volume = 47 | issue = 3 | pages = 230–238 | year = 2006 | pmid = 16479411 | s2cid = 8734069}}</ref> It is likely that the mantled guereza prefers these forests due to the increased number of food trees and the weaker chemical defenses of the species within.<ref name="Lwanga2006" /> The mantled guereza is sometimes found in swamps<ref name="Oates1978">{{Cite journal | last = Oates | first = J. F. | year = 1978 | title = Water-plant and soil consumption by guereza monkeys (''Colobus guereza''): a relationship with minerals and toxins in the diet? | journal = Biotropica | volume = 10 | issue = 4 | pages = 241–253 | doi=10.2307/2387676 | jstor = 2387676 | bibcode = 1978Biotr..10..241O }}</ref> as well as human-made habitats such as ''Eucalyptus'' plantations, which may be frequented when the monkey has nutritional deficiencies.<ref name="DunbarDunbar1974" />
==Ecology==
The mantled guereza is primarily arboreal, but does sometimes descend on the ground to forage and travel, perhaps more so than most other colobines. It is diurnal and rests for up to half the day. Foraging or travelling are the next most common activity. Sometime after dawn, mantled guereza groups leave their sleeping trees and will return to them at dusk. During the day, the mantled guereza has long rest periods in between periods of moving and feeding.<ref name="Bocian1997">{{Cite thesis | last = Bocian | first = C. M. | year = 1997 | title = Niche separation of black-and-white colobus monkeys (''Colobus angolensis'' and ''C. guereza'') in the Ituri Forest | type = Ph.D.| publisher = City University of New York}}</ref><ref name="vonHippel1996" /><ref name="Oates1977a">{{Cite book | last = Oates | first = J. F. | year = 1977a | chapter = The guereza and its food |editor-last = Clutton-Brock | editor-first = T. H. | title = Primate Ecology: Studies of Feeding and Ranging Behaviour in Lemurs, Monkeys and Apes | location = London | publisher = Academic Press | pages = 275–321}}</ref> Other activities, including grooming, greeting, playing and being vigilant, are performed to a lesser extent.<ref name="vonHippel1996" /><ref name="Oates1977a" />
thumb|The diet of the mantled guereza is predominantly leaves, often of only a few tree species. Despite its reputation as an exclusive leaf-eater, the mantled guereza is not an obligate folivore.{{Sfn|Davies|Oates|1994}} While it mainly eats leaves and fruit, its diet is quite variable. It may eat bark, wood, seeds, flowers, petioles, lianas, aquatic-plants, arthropods, soil, and even concrete from buildings.<ref name="HarrisChapman2007">{{Cite journal | last1 = Harris | first1 = T. R. | last2 = Chapman | first2 = C. A. | doi = 10.1007/s10329-006-0036-8 | title = Variation in diet and ranging of black and white colobus monkeys in Kibale National Park, Uganda | journal = Primates | volume = 48 | issue = 3 | pages = 208–221 | year = 2007 | pmid = 17429575 | s2cid = 6986510 | url = http://chapmanresearch.mcgill.ca/Pdf/209_BWRange.pdf | access-date = 2015-09-02 | archive-url = https://web.archive.org/web/20160305055803/http://chapmanresearch.mcgill.ca/Pdf/209_BWRange.pdf | archive-date = 2016-03-05 }}</ref> The amount of each food item in its diet varies by area and time of year. Nutritional factors like protein, tannins, and sodium levels in leaves influence its food choices. It may even intermittently travel longer distances to access plants with higher levels of nutrition.<ref name="FashingDierenfeldMowry2007">{{Cite journal | last1 = Fashing | first1 = P. J. | last2 = Dierenfeld | first2 = E. S. | last3 = Mowry | first3 = C. B. | doi = 10.1007/s10764-006-9096-2 | title = Influence of plant and soil chemistry on food selection, ranging patterns, and biomass of ''Colobus guereza'' in Kakamega Forest, Kenya | journal = International Journal of Primatology | volume = 28 | issue = 3 | page = 673 | year = 2007 | s2cid = 25984104 | url = http://anthro.fullerton.edu/pfashing/publications/Kakamega_Forest.pdf}}</ref> Leaves usually make up over half of its diet, although fruits are occasionally eaten more depending on the season.{{Sfn|Davies|Oates|1994}}<ref name="DunbarDunbar1974" /> When foraging for leaves, the mantled guereza prefers young ones over old.<ref name="Lwanga2006" /> With fleshy fruits, the mantled guereza prefers to eat them unripe, which may serve to reduce competition with primates that eat ripe fruits.<ref name="HarrisChapman2007" /> It consumes a number of plant species but only some make up most of its diet at a specific site.<ref name="Oates1978" /><ref name="HarrisChapman2007" />
Like all colobi, the mantled guereza is able to digest leaves and other plant fibers with a large, multi-chambered stomach that contains bacteria in certain areas.{{Sfn|Oates|Davies|Delson|1994|pp=45–73}} Like most colobines, it prefers foods with high fiber content that can be easily extracted with its specialized stomach.<ref name="FashingDierenfeldMowry2007" /> The mantled guereza is mostly preyed on by the crowned hawk-eagle,<ref name="StuhsakerLeakey1990">{{Cite journal | last1 = Struhsaker | first1 = T. T. | last2 = Leakey | first2 = M. | year = 1990 | title = Prey selectivity by crowned hawk-eagles on monkeys in the Kibale Forest, Uganda | journal = Behavioral Ecology and Sociobiology | volume = 26 | issue = 6 | pages = 435–443 | doi=10.1007/bf00170902| bibcode = 1990BEcoS..26..435S | s2cid = 21024373 }}</ref> but it is also eaten by other birds of prey such as Verreaux's eagle.<ref name="DunbarDunbar1974" /> The common chimpanzee is known to hunt the guereza.<ref name="Ihobe2001">{{Cite journal | last1 = Ihobe | first1 = H. | year = 2001 | title = Hunting attempt by chimpanzees on Abyssinian colobus at the Kalinzu Forest, Uganda | journal = Pan Africa News | volume = 8 | issue = 2 | pages = 31–32| doi = 10.5134/143397 | doi-access = free }}</ref> The leopard is another possible predator.<ref name="Schel2009">{{Cite journal | last1 = Schel | first1 = A. M. | last2 = Tranquilli | first2 = S. | last3 = Zuberbühler | first3 = K. | doi = 10.1037/a0014280 | title = The alarm call system of two species of black-and-white colobus monkeys (''Colobus polykomos'' and ''Colobus guereza'') | journal = Journal of Comparative Psychology | volume = 123 | issue = 2 | pages = 136–150 | year = 2009 | pmid = 19450021 | url = http://doc.rero.ch/record/278686/files/Schel_AM.-The_Alarm_Call_20170203165417-WW.pdf}}</ref>
==Behaviour==
===Social structure=== [[File:Colobus guereza Mantelaffen.JPG|thumb|left|upright|Social grooming or allogrooming mainly occurs between females and is an important social interaction in mantled guereza groups.]] The mantled guereza lives in stable social groups usually containing three to fifteen members.<ref name="vonHippel1996">{{Cite journal | last1 = von Hippel | first1 = F. A. | title = Interactions between overlapping multimale groups of black and white colobus monkeys (''Colobus guereza'') in the Kakamega Forest, Kenya | doi = 10.1002/(SICI)1098-2345(1996)38:3<193::AID-AJP1>3.0.CO;2-U | journal = American Journal of Primatology | volume = 38 | issue = 3 | pages = 193–209 | year = 1996 | pmid = 31918478 | s2cid = 210133123 }}</ref> The groups usually contain one male, several females and juveniles. In some populations, groups containing several males are common.<ref name="Dunbar1976">{{Cite journal | last = Dunbar | first = R. I. M. | title = Contrasts in social structure among black-and-white colobus monkey groups | journal = Animal Behaviour | year = 1976 | volume = 24 | issue = 1 | pages = 84–92 | doi=10.1016/s0003-3472(76)80102-9 | pmid = 817624 | s2cid = 20145070}}</ref> In multi-male groups, males tend to be aggressive with one another with one being dominant. Some males may be expelled from these groups.<ref name="Bocian1997" /> Multi-male groups may contain father-son pairs or unrelated males.<ref name="Harris_etal2009">{{Cite journal | last1 = Harris | first1 = T. R. | last2 = Caillaud | first2 = D. | last3 = Chapman | first3 = C. A. | last4 = Vigilant | first4 = L. | year = 2009 | title = Neither genetic nor observational data alone are sufficient for understanding sex-biased dispersal in a social-group-living species | journal = Molecular Ecology | volume = 18 | issue = 8 | pages = 1777–1790 | doi=10.1111/j.1365-294x.2009.04139.x | pmid=19302351 | bibcode = 2009MolEc..18.1777H | s2cid = 26345361}}</ref> Males that are not part of groups either live solitarily or with other outside males in bachelor groups. The females keep the groups cohesive and they are matrilineally related. They rarely disperse from their natal groups, except possibly when they break apart.<ref name="Bocian1997" /> Males on the other hand, usually leave when they become subadults or adults. They may start out being solitary and or in bachelor groups. They gain entry into a social group either by being on the periphery or displacing a group male.<ref name="DunbarDunbar1974" />
Because of its low quality diet and the dispersed distribution of its food, the mantled guereza has a resident-egalitarian social structure. Female guerezas living in a group often have an egalitarian dominance style with no formalized rank relations. Relationships are relaxed and friendly with rare signals of dominance or subordinance. Physical aggression within the group is usually not harmful and rarely escalates into a conflict. Allogrooming is an important part of mantled guereza interactions and mostly occurs between females.<ref name="GrunauKues2001">{{Cite journal | last1 = Grunau | first1 = T. | last2 = Kuester | first2 = J. | doi = 10.1007/BF02629621 | title = Dominance style in female guerezas (''Colobus guereza'' Rüppell 1835) | journal = Primates | volume = 42 | issue = 4 | page = 301 | year = 2001 | s2cid = 43214796}}</ref> The adult males rarely groom in the groups. While not strictly territorial, mantled guereza groups can be aggressive towards each other.<ref name="vonHippel1996" /> In some populations, groups may defend core areas (which exist as a small part of the home range), resources, and mates. During intergroup encounters, males can engage in direct or indirect mate defense, like defending a female's resources.<ref name="Fashing2001">{{Cite journal | last1 = Fashing | first1 = P. | title = Male and female strategies during intergroup encounters in guerezas (''Colobus guereza''): Evidence for resource defense mediated through males and a comparison with other primates | doi = 10.1007/s002650100358 | journal = Behavioral Ecology and Sociobiology | volume = 50 | issue = 3 | pages = 219–230 | year = 2001 | bibcode = 2001BEcoS..50..219F | s2cid = 12964572 | url = http://anthro.fullerton.edu/pfashing/publications/BES_Guereza_Encounters.pdf}}</ref> It is the males that participate in agonistic inter-group encounters but female may do so as well.<ref name="vonHippel1996" /> Aggressive encounters between groups usually involve chases, displays and vocalizations rather than physical contact.<ref name=vonHippel1996 />
[[File:Colobus guereza-2010.ogv|thumb|Two Mantled guereza in a Japanese zoo.]] ===Reproduction and parenting=== thumb|upright|Infants are born with white fur and are always carried during the first months of their life. The mantled guereza has a polygynous harem-based mating system.{{Sfn|Davies|Oates|1994}}<ref name="Bocian1997" /> Mating solicitations are made by both males and females, half of the time for each.<ref name="HarrisMonfort2006">{{Cite journal | last1 = Harris | first1 = T. R. | last2 = Monfort | first2 = S. L. | doi = 10.1002/ajp.20232 | title = Mating behavior and endocrine profiles of wild black and white colobus monkeys (''Colobus guereza''): Toward an understanding of their life history and mating system | journal = American Journal of Primatology | volume = 68 | issue = 4 | pages = 383–396 | year = 2006 | pmid = 16534807 | s2cid = 7198092}}</ref> To solicit mating, the mantled guereza will walk near its potential partner and make low-intensity mouth clicks or tough-smacks.<ref name="Grimes2000">{{Cite thesis | last = Grimes | first = K. H. | year = 2000 | title = Guereza dietary and behavioural patterns at the Entebbe Botanical Gardens | type = M.A. | publisher = University of Calgary}}</ref> During copulation, the males hold on the female's ankles and body.<ref name="Harris2005">Harris, T. R. (2005). Roaring, intergroup aggression, and feeding competition in black and white colobus monkeys (''Colobus guereza'') at Kanyawara, Kibale National Park, Uganda. Ph.D. thesis. Yale University.</ref> Most matings take place between individuals of the same group but copulations outside of the group have been recorded.<ref name="Harris2005" /> In multi-male groups, more than one male may mate with the females.<ref name="vonHippel1996" /> The gestation period lasts 158 days with a 16–22 month interbirth interval.<ref name="DunbarDunbar1974" /> The newborn guereza relies on its mother for support and must cling to her. As they grow older, infants can move on their own but keep returning to their mothers.<ref name="Horwich1975">{{Cite journal | last1 = Horwich | first1 = R. H. | last2 = Manski | first2 = D. | doi = 10.1007/BF02381799 | title = Maternal care and infant transfer in two species of ''Colobus'' monkeys | journal = Primates | volume = 16 | pages = 49–73 | year = 1975 | s2cid = 45582808 | url = http://www.communityconservation.org/publications/primates16.1.1975.pdf | access-date = 2015-09-02 | archive-url = https://web.archive.org/web/20150923205708/http://www.communityconservation.org/publications/primates16.1.1975.pdf | archive-date = 2015-09-23 }}</ref> The infants take up most of the attention in the groups. The other females in a group may handle an infant although the latter are only comfortable with their mothers.<ref name="Oates1977b">{{Cite journal | last1 = Oates | first1 = J. F. | doi = 10.1111/j.1439-0310.1977.tb01007.x | title = The social life of a black-and-white colobus monkey, ''Colobus guereza''| journal = Zeitschrift für Tierpsychologie | volume = 45 | pages = 1–60 | year = 1977 | issue = 1 | pmid = 414475 | bibcode = 1977Ethol..45....1O }}</ref> The males normally do not pay much attention to infants until they are four to five weeks old.<ref name="Horwich1975" /> Infants can eat solid food at about eight to nine weeks and by fifty weeks they are fully weaned and no longer need to hold on to their mothers.<ref name="Oates1977b" />
===Communication=== The most notable vocalization of the mantled guereza is the "roar", which is made mainly at night or dawn by males. The sound of a roar can be carried for up to a mile. It is normally the dominant male who roars when there are multiple males in the group. Roars are used for long-distance communication and can regulate inter-group spacing without direct, physical contact while foraging.<ref name="SchelZuberbühler2012">{{Cite journal | last1 = Schel | first1 = A. M. | last2 = Zuberbühler | first2 = K. | doi = 10.1007/s00265-011-1282-3 | title = Dawn chorusing in guereza colobus monkeys | journal = Behavioral Ecology and Sociobiology | volume = 66 | issue = 3 | page = 361 | year = 2011 | s2cid = 7149453}}</ref> When one male starts roaring, neighboring males will start to roar as well.<ref name="Harris2005" /> Often, the mantled guereza will respond to calls regardless of "caller identity," focusing more on the collective vocal displays and not the familiarity of the caller.<ref name="SchelZuberbühler2012" /> There is variation in the roars of males which could signal the status of their group and fighting ability.<ref name="Harris2005" /> With a roar, a male can advertise his body size; both actual and exaggerated.<ref name="Harris_etal2006">{{Cite journal | last1 = Harris | first1 = T. R. | last2 = Fitch | first2 = W. T. | last3 = Goldstein | first3 = L. M. | last4 = Fashing | first4 = P. J. | title = Black and white colobus monkey (''Colobus guereza'') roars as a source of both honest and exaggerated information about body mass | doi = 10.1111/j.1439-0310.2006.01247.x | journal = Ethology | volume = 112 | issue = 9 | page = 911 | year = 2006 | bibcode = 2006Ethol.112..911H | url = http://anthro.fullerton.edu/pfashing/publications/bandw_colobine_monkeys.pdf}}</ref> Other vocalizations are made as well. Males may snort, possibly as an alarm call. "Purrs" are made before group movements. Females and infants may "caw" when under mild distress. When in more serious distress, like if an infant is in danger, females and sub-adults will squeak or scream. "Tongue-clicking" is made during mild aggression.<ref name="Marler1972">{{Cite journal | last1 = Marler | first1 = P. | title = Vocalizations of East African monkeys II: black and white colobus | doi = 10.1163/156853972X00266 | journal = Behaviour | volume = 42 | issue = 3 | pages = 175–197 | year = 1972}}</ref> In addition to vocalizations, the mantled guereza communicates with several different body postures and movements, displaying of fringe fur, facial expressions, and touches.<ref name="Oates1977b" />
==Conservation status== thumb|upright|The mantled guereza is hunted for its skin and meat. Because it can live in both dry and gallery forests and move on the ground, the mantled guereza is less threatened than many other colobine species.{{Sfn|Oates|1994b|pp=347–358}} The IUCN lists it as Least Concern because "although locally threatened in parts of its range, this widespread species is not thought to be declining fast enough to place it in a higher category of threat."<ref name="iucn status 11 November 2021" /> However, some of the subspecies are classified under different categories. The Mt Uaraguess guereza, ''C. g. percivali'', is listed as Endangered due to its small range and its risk from hunting,<ref name="IUCN_percivali">{{cite iucn |author=Mwenja, I. |date=2019 |title=''Colobus guereza'' ssp. ''percivali'' |volume=2019 |article-number=e.T40007A17983118 |doi=10.2305/IUCN.UK.2019-3.RLTS.T40007A17983118.en |access-date=11 November 2021}}</ref> while the Dodinga Hills guereza, ''C. g. dodingae'', the Djaffa Mountains guereza, ''C. g. gallarum'', and the Mau Forest guereza, ''C. g. matschiei'' are all listed as Data Deficient.<ref name="IUCN_dodingae">{{cite iucn |author=Butynski, T.M. |author2=de Jong, Y.A. |date=2020 |title=''Colobus guereza'' ssp. ''dodingae'' |volume=2020 |article-number=e.T136880A17983306 |doi=10.2305/IUCN.UK.2020-2.RLTS.T136880A17983306.en |access-date=11 November 2021}}</ref><ref name="IUCN_gallarum">{{cite iucn |author=Fashing, P.J. |author2=Oates, J.F. |date=2019 |title=''Colobus guereza'' ssp. ''gallarum'' |volume=2019 |article-number=e.T5150A17983175 |doi=10.2305/IUCN.UK.2019-3.RLTS.T5150A17983175.en |access-date=11 November 2021}}</ref><ref name="IUCN_matschiei">{{cite iucn |author=Butynski, T.M. |author2=de Jong, Y.A. |date=2020 |title=''Colobus guereza'' ssp. ''matschiei'' |volume=2020 |article-number=e.T136846A176219904 |doi=10.2305/IUCN.UK.2020-3.RLTS.T136846A176219904.en |access-date=11 November 2021}}</ref>
The Dodinga Hills guereza has not been recorded since the 1960s.<ref name="IUCN_dodingae"/> Unlike most other primate species, the mantled guereza can survive habitat degradation and can even thrive in degraded forests.<ref name="Chapman_etal2000">{{Cite journal | last1 = Chapman | first1 = C. A. | last2 = Balcomb | first2 = S. R. | last3 = Gillespie | first3 = T. R. | last4 = Skorupa | first4 = J. P. | last5 = Struhsaker | first5 = T. T. | title = Long-term effects of logging on African primate communities: A 28-year comparison from Kibale National Park, Uganda | doi = 10.1046/j.1523-1739.2000.98592.x | journal = Conservation Biology | volume = 14 | pages = 207–217 | year = 2000 | s2cid = 6827577 | url = http://www.envs.emory.edu/faculty/GILLESPIE/publications/chapmanetal2000.pdf | access-date = 2015-09-04 | archive-date = 2021-03-03 | archive-url = https://web.archive.org/web/20210303052944/http://www.envs.emory.edu/faculty/GILLESPIE/publications/chapmanetal2000.pdf }}</ref> Sometimes, logging may increase the number of preferred food trees for the mantled guereza and it is more abundant in logged areas than unlogged ones.{{Sfn|Oates|1994b|pp=347–358}} However, complete forest clearance causes dramatic declines in numbers. In Uganda complete forest clearings caused a decline of 50% over eight years.<ref name="Chapman_etal2007">{{Cite journal | last1 = Chapman | first1 = C. A. | last2 = Naughton-Treves | first2 = L. | last3 = Lawes | first3 = M. J. | last4 = Wasserman | first4 = M. D. | last5 = Gillespie | first5 = T. R. | title = Population declines of Colobus in western Uganda and conservation value of forest fragments | doi = 10.1007/s10764-007-9142-8 | journal = International Journal of Primatology | volume = 28 | issue = 3 | page = 513 | year = 2007 | s2cid = 20186034 | url = http://chapmanresearch.mcgill.ca/Pdf/210_FragmentReCensus.pdf | access-date = 2015-09-02 | archive-url = https://web.archive.org/web/20140222195949/http://chapmanresearch.mcgill.ca/Pdf/210_FragmentReCensus.pdf | archive-date = 2014-02-22 }}</ref> The mantled guereza is also threatened by hunting for meat and its skin. Mantled guereza meat sells as bushmeat for $4–9 US.<ref name="EvesRuggiero2000">{{Cite book | last1 = Eves | first1 = H. E. | last2 = Ruggiero | first2 = R. G. | year = 2000 | chapter = Socioeconomics and the sustainability of hunting in the forests of northern Congo (Brazzaville) | editor1-last = Robinson | editor1-first = J. G. | editor2-last = Bennett | editor2-first = E. L. | title = Hunting for Sustainability in Tropical Forests | url = https://archive.org/details/huntingforsustai00robi | url-access = limited | location = New York | publisher = Columbia University Press | pages = [https://archive.org/details/huntingforsustai00robi/page/n449 427]–454 | isbn = 978-0-231-50492-8}}</ref> The skins have been sold for fashion or in the tourist trade.<ref name="Oates1977c">{{Cite book | last = Oates | first = J. F. | year = 1977c | chapter = The guereza and man | editor1 = Rainier III, Prince of Monaco | editor1-link = Rainier III, Prince of Monaco | editor2 = Bourne, G. H. | editor2-link = Geoffrey Bourne (anatomist) | title = Primate Conservation | location = New York | publisher = Academic Press | pages = 419–467 | isbn = 978-0-12-576150-5}}</ref>
==References== {{Reflist}}
==Cited sources== {{refbegin}} *{{Cite book | year = 1994 | editor1-last = Davies | editor1-first = A. G. | editor2-last = Oates | editor2-first = J. F. | title = Colobine Monkeys: Their Ecology, Behaviour and Evolution | location = Cambridge, UK | publisher = Cambridge University Press | isbn = 978-0-521-33153-1}} **{{Cite book | year = 1994 | last1 = Oates | first1 = J. F. | last2 = Davies | first2 = A. G. | last3 = Delson | first3 = E. | title = The diversity of living colobines | pages = 45–73}} **{{Cite book | year = 1994a | last1 = Oates | title = The natural history of African colobines | pages = 75–128}} **{{Cite book | year = 1994b | last = Oates | first = J. F. | title = Conclusions: the past, present and future of the colobines | pages = 347–358}} {{refend}}
==External links== *[https://primate.wisc.edu/primate-info-net/pin-factsheets/pin-factsheet-mantled-guereza/ Primate Info Net ''Colobus guereza'' Factsheet] *ARKive – [https://archive.today/20130414065258/http://www.arkive.org/species/GES/mammals/Colobus_guereza/ Images and movies of the Eastern black-and-white colobus ''(Colobus guereza)'']
{{C.Colobinae nav}} {{Taxonbar|from=Q628239}}
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