Technical ReportPDF Available

Adolf Friedrichs’s Angolan Colobus (Colobus angolensis ruwenzorii)

Authors:
  • Lolldaiga Hills Research Programme, Sustainability Centre Eastern Africa
  • Eastern Africa Primate Diversity and Conservation Program, Kenya

Abstract

Butynski, T.M. & de Jong, Y.A. 2020. Colobus angolensis ssp. ruwenzorii. The IUCN Red List of Threatened Species 2020: e.T5147A17983385. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T5147A17983385.en.
The IUCN Red List of Threatened Species™
ISSN 2307-8235 (online)
IUCN 2020: T5147A17983385
Scope(s): Global
Language: English
Colobus angolensis ssp. ruwenzorii, Adolf Friedrichs’s
Angolan Colobus
Assessment by: Butynski, T.M. & de Jong, Y.A.
View on www.iucnredlist.org
Citation: Butynski, T.M. & de Jong, Y.A. 2020. Colobus angolensis ssp. ruwenzorii. The IUCN Red List
of Threatened Species 2020: e.T5147A17983385. https://dx.doi.org/10.2305/IUCN.UK.2020-
2.RLTS.T5147A17983385.en
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THE IUCN RED LIST OF THREATENED SPECIES™
Taxonomy
Kingdom Phylum Class Order Family
Animalia Chordata Mammalia Primates Cercopithecidae
Scientific Name:ÊÊColobus angolensis ssp. ruwenzorii Thomas, 1901
Synonym(s):
Colobus angolensis ssp. adolfi-friederici Matschie, 1914
Parent Species:ÊÊSee Colobus angolensis
Common Name(s):
• English: Adolf Friedrichs’s Angolan Colobus, Adolf Friedrich's Angola Colobus, Rwenzori
Black-and-white Colobus
Taxonomic Source(s):
Mittermeier, R.A., Rylands, A.B. and Wilson D.E. 2013. Handbook of the Mammals of the World: Volume
3 Primates. Lynx Edicions, Barcelona.
Taxonomic Notes:
This account follows the taxonomy of Groves (2001, 2005, 2007), Grubb et al. (2003), and Bocian and
Anderson (2013).
Assessment Information
Red List Category & Criteria: Data Deficient ver 3.1
Year Published: 2020
Date Assessed: March 20, 2018
Justification:
Colobus angolensis ruwenzorii is listed as Data Deficient as information on its distribution and
abundance are inadequate for a Red List assessment. While the edges of the geographic distribution of
this subspecies are thought to be approximately known, the distribution is highly fragmented. The
number and limits of the many fragments are not known. What is known is that these fragments are
widely-spaced. Its extent of occurrence (EOO) is unlikely to be >121,000 km², and its area of occupancy
(AOO) is unlikely to be >12,120 km²). The habitat of C. a. ruwenzorii continues to be degraded, lost, and
fragmented, while poaching is an additional threat.
Previously Published Red List Assessments
2008 – Vulnerable (VU)
https://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T5147A11117676.en
2000 – Vulnerable (VU)
1996 – Vulnerable (VU)
© The IUCN Red List of Threatened Species: Colobus angolensis ssp. ruwenzorii – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T5147A17983385.en
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Geographic Range
Range Description:
Colobus angolensis ruwenzorii occurs in many isolated populations, varying in size from <1 km² to ca
7,000 km² (Nyungwe National Park). This subspecies occurs along both sides of the Western (Albertine)
Rift Valley, from the Semliki Valley and the Rwenzori Mountains of extreme east Democratic Republic of
Congo and extreme west Uganda, southwards to southwest Rwanda (Nyungwe National Park) and
northwest Burundi (Kabara National Park). It is also recorded at Lake Nabugabo and along the west edge
of Lake Victoria in Uganda (Sango Bay) and just across the Uganda-Tanzania border in Tanzania (Minziro
Forest). Known altitudinal limits are 1,150-2,415 m asl (De Jong and Butynski 2018).
Area of occupancy (AOO) for this subspecies is ca 12,120 km², within an extent of occurrence (EOO) of
120,592 km².
Country Occurrence:
Native, Extant (resident): Burundi; Congo, The Democratic Republic of the; Rwanda; Tanzania, United
Republic of; Uganda
© The IUCN Red List of Threatened Species: Colobus angolensis ssp. ruwenzorii – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T5147A17983385.en
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Distribution Map
© The IUCN Red List of Threatened Species: Colobus angolensis ssp. ruwenzorii – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T5147A17983385.en
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Population
Colobus angolensis ruwenzorii live in complex societies with >300 individuals in permanent groups in
Nyungwe Forest National Park (Plumptre et al. 2002, Fashing et al. 2007). One band of 130 individuals at
Lake Nabugabo was organized into 12 units, each of 4-23 individuals (Stead and Teichroeb 2019). Brief
observations at some other sites suggest that small groups are typical elsewhere, such as in Sango Bay
Forest (Oates 1974, Y. de Jong and T. Butynski pers. obs.), and Rwenzori Mountains (T. Butynski pers.
obs.), but more detailed study might find that these sites also have multi-tiered C. a. ruwenzorii
societies. Given the threats facing the species, it is suspected that populations are in decline.
Current Population Trend:ÊÊDecreasing
Habitat and Ecology (see Appendix for additional information)
Colobus a. ruwenzorii is most common in the montane forest of the Western Rift Valley but also present
in lowland forests on the west edge of Lake Victoria (Oates 1974, Perkin and Bearder 2004, Stead and
Teichroeb 2019). Detail information on habitat, ecology, and behaviour is presented in Fashing et al.
(2007) and Stead and Teichroeb (2019).
Systems:ÊÊTerrestrial
Use and Trade
Little information is available for this subspecies. Poaching is a threat. As for other black-and-white
colobus, this subspecies is probably used for traditional ceremonies.
Threats (see Appendix for additional information)
Little range-wide information on the current conservation status of this subspecies is available. Colobus
a. ruwenzoriis geographic range has decreased greatly over the past 50 years due to habitat loss as the
soils and climates where this subspecies occurs are of high value for agriculture.
Threatened by both legal and illegal logging in forest fragments near Lake Nabugabo and large-scale
anthropogenic changes to the environment over much of its geographic range (Teichroeb et al. 2019,
Adams and Teichroeb 2020, Y. de Jong and T. Butynski pers. obs.).
The ‘Rate of Natural Increase’ of the human population within the geographic range of C. a. ruwenzorii is
high (2.7-3.2%; PRB 2019). The geographic range of C. a. ruwenzorii has greatly decreased and
fragmented in recent decades as a result of human encroachment. Forest degradation, loss, and
fragmentation of natural habitats is taking place as people seek land for farms, exotic tree plantations,
roads and settlements, as well as forest resources such as timber, building poles, fuelwood, and
charcoal. Poaching is another threat.
Conservation Actions (see Appendix for additional information)
Occurs in several protected areas, including Nyungwe National Park (Rwanda), Kabira National Park
(Burundi), Rwenzori National Park (Uganda), Virunga National Park (Democratic Republic of Congo), and
forest reserves along the western edge of Lake Victoria (Uganda, Tanzania).
© The IUCN Red List of Threatened Species: Colobus angolensis ssp. ruwenzorii – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T5147A17983385.en
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No direct conservation action has been taken or is planned to ensure the long-term survival of C. a.
ruwenzorii. A detailed assessment of the current conservation status of C. a. ruwenzorii is required,
particularly its abundance, limits of its geographic range, numbers of populations, and local threats.
There is a small population of black-and white colobus monkeys in Uganda’s Lake Mburu National Park.
It is a priority to determine which species/subspecies this is. This is likely to be either C. a. ruwenzorii or
Colobus guereza occidentalis.
Credits
Assessor(s): Butynski, T.M. & de Jong, Y.A.
Reviewer(s): Reuter, K.E.
Contributor(s): Kingdon, J., Struhsaker, T.T., Oates, J.F., Hart, J.A. & Groves, C.P.
Authority/Authorities: IUCN SSC Primate Specialist Group
© The IUCN Red List of Threatened Species: Colobus angolensis ssp. ruwenzorii – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T5147A17983385.en
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Bibliography
Adams, F.V. and Teichroeb, J.A. 2020. Microhabitat use in Angolan colobus monkeys (Colobus angolensis
ruwenzorii) at Nabugabo, Uganda demonstrates intraspecific variability. International Journal of
Primatology.
Bocian, C.M. and Anderson, J. 2013. Colobus angolensis Angola Colobus (Angola Black-and-white
Colobus, Angola Pied Colobus). In: T.M. Butynski, J. Kingdon and J. Kalina (eds), The Mammals of Africa.
Volume II: Primates, pp. 103–108. Bloomsbury Publishing, London.
De Jong, Y.A. and Butynski, T.M. 2018. Primates of East Africa: Pocket Identification Guide. Global
Wildlife Conservation.
Fashing P.J., Mulindahabi, F. Gakima, J., Masozera, M. Mununura, I., Plumptre, A.J. and Nguyen, N. 2007.
Activity and ranging patterns of Colobus angolensis ruwenzorii in Nyungwe Forest, Rwanda: Possible
costs of large group size. International Journal of Primatology 28: 673-703.
Groves C.P. 2001. Primate Taxonomy. Smithsonian Institution Press, Washington, DC, USA.
Groves, C.P. 2005. Order Primates. In: D.E. Wilson and D.M. Reeder (eds), Mammal Species of the World,
pp. 111-184. The Johns Hopkins University Press, Baltimore, Maryland, USA.
Groves, C.P. 2005. Order Primates. In: D.E. Wilson & D.M. Reeder (eds). Mammal Species of the World. A
Taxonomic and Geographic Reference. Third edition. Volume 1, pp. 111-184.The Johns Hopkins
University Press, Baltimore, Maryland.
Groves, C.P. 2007. The taxonomic diversity of the Colobinae of Africa. Journal of Anthropological
Sciences 85: 7-34.
Grubb, P., Butynski, T.M., Oates, J.F., Bearder, S.K., Disotell, T.R., Groves, C.P. and Struhsaker, T.T. 2003.
Assessment of the diversity of African primates. International Journal of Primatology 24(6): 1301-1357.
IUCN. 2020. The IUCN Red List of Threatened Species. Version 2020-2. Available at: www.iucnredlist.org.
(Accessed: 13 June 2020).
Oates, J.F. 1974. The ecology and behaviour of the black-and-white colobus monkey (Colobus guereza
Rüppell) in East African. PhD thesis. University of London.
Pacifici, M., Santini, L., Di Marco, M., Baisero, D., Francucci, L., Grottolo Marasini, G., Visconti, P. and
Rondinini, C. 2013. Generation length for mammals. Nature Conservation 5: 87–94.
Perkin, A.W. and Bearder, S.K. 2004. Minziro Forest reveals new galago and bat records for Tanzania. .
The Arc Journal 16: 9-10.
Plumptre, A.J., Masozera, M., Fashing, P.J., McNeilage, A., Ewango, C., Kaplin, B.A. and Liengola, I. 2002.
Biodiversity surveys of the Nyungwe Forest Reserve in S.W. Rwanda. WCS Working Paper 19: 1-95.
PRB. 2019. World Population Sheet. In: Population Reference Bureau (ed.). Washington, DC, USA.
Stead, M.S and Teichroeb. 2019. A multi-level society comprised of one-male and multi-male core units
in an African colobine (Colobus angolensis ruwenzorii). PLOS ONE 14(10): e0217666.
Teichroeb, J.A., Bridgett, G.R., Corriveau, A, and Twinomugisha, D. 2019. The immediate impact of
selective logging on Angolan colobus (Colobus angolensis ruwenzorii) at Lake Nabugabo, Uganda. In:
Behie A.M., Teichroeb, J.A. and Malone, N. (eds), Primate Research and Conservation in the
Anthropocene, Cambridge University Press, Cambridge, UK.
© The IUCN Red List of Threatened Species: Colobus angolensis ssp. ruwenzorii – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T5147A17983385.en
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Citation
Butynski, T.M. & de Jong, Y.A. 2020. Colobus angolensis ssp. ruwenzorii. The IUCN Red List of Threatened
Species 2020: e.T5147A17983385. https://dx.doi.org/10.2305/IUCN.UK.2020-
2.RLTS.T5147A17983385.en
Disclaimer
To make use of this information, please check the Terms of Use.
External Resources
For Supplementary Material, and for Images and External Links to Additional Information, please see the
Red List website.
© The IUCN Red List of Threatened Species: Colobus angolensis ssp. ruwenzorii – published in 2020.
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Appendix
Habitats
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Habitat Season Suitability Major
Importance?
1. Forest -> 1.6. Forest - Subtropical/Tropical Moist Lowland Resident Suitable Yes
1. Forest -> 1.9. Forest - Subtropical/Tropical Moist Montane Resident Suitable Yes
Use and Trade
(http://www.iucnredlist.org/technical-documents/classification-schemes)
End Use Local National International
Food - human No Yes Yes
Threats
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Threat Timing Scope Severity Impact Score
2. Agriculture & aquaculture -> 2.1. Annual &
perennial non-timber crops -> 2.1.1. Shifting
agriculture
Ongoing Unknown Unknown Unknown
2. Agriculture & aquaculture -> 2.1. Annual &
perennial non-timber crops -> 2.1.2. Small-holder
farming
Ongoing Unknown Unknown Unknown
5. Biological resource use -> 5.1. Hunting & trapping
terrestrial animals -> 5.1.1. Intentional use (species is
the target)
Ongoing Minority (50%) Slow, significant
declines
Low impact: 5
5. Biological resource use -> 5.3. Logging & wood
harvesting -> 5.3.5. Motivation
Unknown/Unrecorded
Ongoing Unknown Unknown Unknown
Conservation Actions in Place
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Conservation Action in Place
In-place land/water protection
Occurs in at least one protected area: Yes
Conservation Actions Needed
© The IUCN Red List of Threatened Species: Colobus angolensis ssp. ruwenzorii – published in 2020.
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(http://www.iucnredlist.org/technical-documents/classification-schemes)
Conservation Action Needed
1. Land/water protection -> 1.1. Site/area protection
1. Land/water protection -> 1.2. Resource & habitat protection
2. Land/water management -> 2.1. Site/area management
3. Species management -> 3.1. Species management -> 3.1.1. Harvest management
Research Needed
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Research Needed
1. Research -> 1.1. Taxonomy
1. Research -> 1.2. Population size, distribution & trends
1. Research -> 1.4. Harvest, use & livelihoods
1. Research -> 1.6. Actions
2. Conservation Planning -> 2.1. Species Action/Recovery Plan
3. Monitoring -> 3.1. Population trends
3. Monitoring -> 3.2. Harvest level trends
3. Monitoring -> 3.3. Trade trends
3. Monitoring -> 3.4. Habitat trends
Additional Data Fields
Distribution
Estimated area of occupancy (AOO) (km²): 12120
Continuing decline in area of occupancy (AOO): Yes
Estimated extent of occurrence (EOO) (km²): 120592
Continuing decline in extent of occurrence (EOO): Yes
Number of Locations: 9
Lower elevation limit (m): 1,150
Upper elevation limit (m): 2,415
Population
Extreme fluctuations: Unknown
Population severely fragmented: Yes
© The IUCN Red List of Threatened Species: Colobus angolensis ssp. ruwenzorii – published in 2020.
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Population
Continuing decline in subpopulations: Unknown
Extreme fluctuations in subpopulations: Unknown
All individuals in one subpopulation: No
Habitats and Ecology
Continuing decline in area, extent and/or quality of habitat: Yes
Generation Length (years): 10.5
© The IUCN Red List of Threatened Species: Colobus angolensis ssp. ruwenzorii – published in 2020.
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The IUCN Red List of Threatened Species™
ISSN 2307-8235 (online)
IUCN 2020: T5147A17983385
Scope(s): Global
Language: English
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The IUCN Red List of Threatened Species™ is produced and managed by the IUCN Global Species
Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership.
The IUCN Red List Partners are: Arizona State University; BirdLife International; Botanic Gardens
Conservation International; Conservation International; NatureServe; Royal Botanic Gardens, Kew;
Sapienza University of Rome; Texas A&M University; and Zoological Society of London.
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ResearchGate has not been able to resolve any citations for this publication.
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Large-scale anthropogenic changes to the environment are making it vital to investigate habitat use so that we can better understand species’ basic ecological needs in order to create successful conservation plans. Some species are very flexible in their habitat requirements. One such species may be Colobus angolensis ruwenzorii, monkeys that occupy montane and tropical lowland forest. In the mountains of southwestern Rwanda, this species spends a great deal of time on the ground and feeds mainly on mature leaves and lichens, but the habitat use of lower altitude populations is unknown. We examined the fine-scale habitat use of C. a. ruwenzorii at Nabugabo, Uganda (1136 m altitude), where they feed primarily on young leaves and fruits. We used data collected over 9 mo (94 days between July 2017 and April 2018) on 117–131 colobus in 12 core units in a multilevel society. We found that colobus individuals were rarely on the ground, and resting and social behavior occurred at higher heights and in larger trees than feeding and moving. Individual height in the canopy followed a daily pattern (higher at the start and end, with a decrease in the middle of the day) and colobus were at lower heights when group size was greater because of core unit fusion. Finally, we found that tree species were generally used relative to their availability in the forest and their value as food species. Given greater predation risk in smaller groups and lower in the canopy at this site, our results suggest that perceived risk has an important effect on microhabitat use in C. a. ruwenzorii at lower altitude. Our results demonstrate the ecological flexibility of this primate species, which bodes well for their continued conservation.
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Th e colobine monkeys of Africa are much more diverse than is often realized; in the case of Red Colobus (genus Piliocolobus), this is because the species replace each other geographically, and there is even some interbreeding where their ranges meet. It is not possible to make a modern taxonomic revision of Black-and-white Colobus (genus Colobus), in the absence of a thorough modern study to determine consistency of the diff erences between the taxa deemed to be subspecies of the two polytypic species, C. angolensis and C. guereza. Red Colobus, in particular, are by their behaviour extremely vulnerable, and one species is presumed extinct, and another has not been seen for some years.