Technical ReportPDF Available

Eastern patas monkey (Erythrocebus patas pyrrhonotus)

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

Abstract

De Jong, Y.A. & Butynski, T.M. 2020. Erythrocebus patas ssp. pyrrhonotus. The IUCN Red List of Threatened Species 2020: e.T92252480A92252486. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en.
The IUCN Red List of Threatened Species™
ISSN 2307-8235 (online)
IUCN 2020: T92252480A92252486
Scope(s): Global
Language: English
Erythrocebus patas ssp. pyrrhonotus, Eastern Patas Monkey
Assessment by: de Jong, Y.A. & Butynski, T.M.
View on www.iucnredlist.org
Citation: de Jong, Y.A. & Butynski, T.M. 2020. Erythrocebus patas ssp. pyrrhonotus. The IUCN Red
List of Threatened Species 2020: e.T92252480A92252486.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.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:ÊÊErythrocebus patas ssp. pyrrhonotus (Hemprich & Ehrenberg, 1829)
Common Name(s):
• English: Eastern Patas Monkey
Taxonomic Notes:
Groves (2001), Grubb et al. (2003), and Kingdon et al. (2008) treat Erythrocebus patas as a monotypic
species in a monotypic genus. Schwarz (1927), Butynski et al. (2013), Isbell (2013), and De Jong and
Butynski (2018) recognize pyrrhonotus as one of the three subspecies within E. patas (patas,
pyrrhonotus, baumstarki). Verheyen (1962), Hill (1966), Napier & Napier (1967), Dandelot (1968, 1974),
and Kingdon (1971, 1997, 2015) recognize an additional subspecies, E. p. villiersi.
In the previous Red List assessment (Kingdon et al. 2008), Erythrocebus was taken to be a monotypic
genus and Erythrocebus patas was taken to be a monotypic species. Here we recognize pyrrhonotus as
one of the three subspecies of E. patas (patas, pyrrhonotus, villiersi).
Assessment Information
Red List Category & Criteria: Vulnerable A4cd ver 3.1
Year Published: 2020
Date Assessed: July 27, 2017
Justification:
Eastern Patas Monkey is listed as Vulnerable. Although Erythrocebus patas pyrrhonotus has a wide
geographic range, there is an inferred ongoing population reduction throughout the range of >30% over
a three-generation period. This decline is expected to continue as the causes (mainly habitat
degradation, fragmentation, and loss) are ongoing. Extent of occurrence and area of occupancy are in
decline. The current level of exploitation is not likely to be reduced.
Geographic Range
Range Description:
Distributed from southeast Chad (e.g., Zakouma National Park) and east Central African Republic,
through Sudan to west Ethiopia, southwards through north Uganda (e.g., Kidepo Valley National Park,
Pian Upe National Park) to northwest and central Kenya (e.g., West-Pokot County, Laikipia County; De
Jong et al. 2008; De Jong and Butynski 2012, 2013, 2014; Butynski and De Jong 2014a). The west
geographic limits of this subspecies are unclear.
Country Occurrence:
© The IUCN Red List of Threatened Species: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en
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Native, Extant (resident): Central African Republic; Chad; Congo, The Democratic Republic of the;
Ethiopia; Kenya; South Sudan; Sudan; Uganda
© The IUCN Red List of Threatened Species: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en
2
Distribution Map
© The IUCN Red List of Threatened Species: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en
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Population
Typical density might be 1.5 animals/km². Hall (1965) recorded 110 patas in a 3,112 km² area in north
Uganda. In Kidepo Valley National Park, northeast Uganda, the rate of encounter with E. p. pyrrhonotus
from a slow-moving vehicle was 0.05 groups/h (0.002 groups/km; Butynski and De Jong in prep.).
In Kenya, the geographic range of E. p. pyrrhonotus declined from ca. 93,120 km² in 1995 to ca. 52,520
km² in 2014 (a 44% decline), and the size of the gaps among populations increased (De Jong et al. 2008;
De Jong and Butynski 2014). Current geographic range of E. p. pyrrhonotus in Kenya is ca. 56% of the
known historic (pre-1995) range (De Jong and Butynski 2014).
Population status of E. p. pyrrhonotus in Ethiopia is unknown. M. Ashagrie (pers. comm. 2016) reports at
least eight groups in northwest Ethiopia (two groups around Assossa, four groups in Alatish National
Park, one group at Metema, and one group at Kafta Humera).
The population is suspected to be undergoing continuous decline of at least 30% over a three
generation period due to habitat degradation and exploitation.
Current Population Trend:ÊÊDecreasing
Habitat and Ecology (see Appendix for additional information)
Erythrocebus patas pyrrhonotus is a medium-sized, diurnal, largely terrestrial, monkey. The species
occupies vegetation types ranging from grassland, to wooded savanna, to woodland (Isbell 2013), and is
most common in thinly bushed Acacia woodland. The species appears to have a preference for
woodland-grassland margins. Generally avoids dense vegetation, including riverine forest (Hall 1965,
Isbell 2013). In East Africa, E. p. pyrrhonotus is strongly associated with whistling thorn Acacia
drepanolobium open woodland (Isbell 1998).
Erythrocebus patas pyrrhonotus is omnivorous, feeding on gums, arthropods, berries, flowers, fruits,
and seeds (Chism and Rowell 1988; De Jong et al. 2008; Isbell 2013; Ashagrie 2015). Visits to water are
typically daily during the dry season. Erythrocebus patas pyrrhonotus often use artificial water sources
and are also known to use fences to sit on and scan from. In all areas where encountered in Kenya, they
are somewhat habituated to humans, mainly to pastoralists, farmers and 'monkey chasers' in crop fields.
In Busia District, west Kenya, they have adapted to an area with a high human population and little
natural vegetation. Here, E. p. pyrrhonotus eat maize and other crops (De Jong et al. 2008; Butynski and
De Jong 2014b). In western Ethiopia, they frequently raids farms (including fruit farms and cotton
plantations; Ashagrie 2015). In Kidepo Valley National Park, northeast Uganda, they raid garbage bins on
a daily basis (Butynski and De Jong 2014a).
Erythrocebus patas pyrrhonotus lives in single-male groups averaging ca. 15 individuals. Home ranges
are large (e.g., 52 km² for one group of 31 individuals in north Uganda; Hall 1965). Burnham (2004)
reported longer day ranges for all-male groups (mean 7.3 km/day) compared with social groups (mean
4.7 km/day) in the same area of Laikipia County, central Kenya. The home range size of social groups is
23-40 km² in Laikipia County, depending on group size (Chism and Rowell 1988; Enstam and Isbell 2004),
but as large as 52 km² in north Uganda (Hall 1965).
© The IUCN Red List of Threatened Species: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en
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Systems:ÊÊTerrestrial
Use and Trade
There is some subsistence hunting of this species.
Threats (see Appendix for additional information)
Main threats to Erythocebus patas pyrrhonotus throughout their range are habitat degradation,
fragmentation, and loss due primarily to agricultural expansion and intensification (both crops and
livestock), charcoal production, and 'development' activities (e.g., settlements, roads, powerlines,
dams). Human populations are doubling every 20-30 years over much of the range of E. p. pyrrhonotus.
As such, there is ever-increasing competition between people and E. p. pyrrhonotus for habitat and
water (De Jong et al. 2008, Isbell 2013; Butynski and De Jong 2014b; Ashagrie 2015). Erythrocebus. p.
pyrrhonotus habitat is highly threatened by human-induced fires in north-west Ethiopia, including
protected areas (Ashagrie 2015).
Conservation Actions (see Appendix for additional information)
Relatively common in Kidepo Valley National Park and Murchison Falls National Park (Uganda). Present
in Pian Upe National Park, east Uganda (Butynski and De Jong 2014a) and in Mago National Park, Omo
National and Gambella National Park (western Ethiopia); M. Ashagrie pers. comm. 2016).
Laikipia County probably holds the largest population of E. patas in Kenya (Isbell and Chism 2007, De
Jong et al. 2008, Butynski and De Jong 2014b). All patas groups in this area occur outside officially
protected areas. Most live on large, private, livestock ranches where there are large areas of Acacia
drepanolobium woodland and artificial sources of water.
Credits
Assessor(s): de Jong, Y.A. & Butynski, T.M.
Reviewer(s): Reuter, K.E.
Facilitator(s) and
Compiler(s):
Williamson, E.A.
Authority/Authorities: IUCN SSC Primate Specialist Group
© The IUCN Red List of Threatened Species: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en
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Butynski, T.M. and De Jong, Y.A. 2014. Biogeography, Taxonomy, Abundance, and Conservation Status of
the Primates of North-eastern Uganda. Unpublished Report to the National Geographic Society.
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monkey Erythrocebus patas in Kenya. Journal of East African Natural History 97(1): 83-102.
Enstam, K.L. and Isbell, L.A. 2004. Microhabitat preferences and vertical use of space by patas monkeys
(Erythrocebus patas) in relation to predation risk and habitat structure. Folia Primtologica 75: 70-84.
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Isbell, L.A. 1998. Diet for a small primate: insectivory and gummivory in the (large) patas monkey
(Erythrocebus patas pyrrhonotus). American Journal of Primatology 45: 381-398.
© The IUCN Red List of Threatened Species: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en
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Kingdon and J. Kalina (eds), The Mammals of Africa. Volume II: Primates, pp. 257-264. Bloomsbury
Publishing, London.
Isbell, L. A. and Chism, J. 2007. Distribution and abundance of patas monkeys (Erythrocebus patas) in
Laikipia, Kenya, 1979-2004. American Journal of Primatology 69: 1223-1235.
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Citation
de Jong, Y.A. & Butynski, T.M. 2020. Erythrocebus patas ssp. pyrrhonotus. The IUCN Red List of
Threatened Species 2020: e.T92252480A92252486. https://dx.doi.org/10.2305/IUCN.UK.2020-
2.RLTS.T92252480A92252486.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: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en
7
Appendix
Habitats
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Habitat Season Suitability Major
Importance?
1. Forest -> 1.5. Forest - Subtropical/Tropical Dry Resident Suitable -
2. Savanna -> 2.1. Savanna - Dry Resident Suitable -
3. Shrubland -> 3.5. Shrubland - Subtropical/Tropical Dry Resident Suitable -
4. Grassland -> 4.5. Grassland - Subtropical/Tropical Dry Resident Suitable -
4. Grassland -> 4.6. Grassland - Subtropical/Tropical Seasonally
Wet/Flooded
Resident Suitable -
14. Artificial/Terrestrial -> 14.1. Artificial/Terrestrial - Arable Land - Marginal -
14. Artificial/Terrestrial -> 14.2. Artificial/Terrestrial - Pastureland - Marginal -
14. Artificial/Terrestrial -> 14.3. Artificial/Terrestrial - Plantations Resident Marginal -
Use and Trade
(http://www.iucnredlist.org/technical-documents/classification-schemes)
End Use Local National International
Food - human No No 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 -> 2.1.2. Small-holder
farming
Ongoing - - Low impact: 3
2. Agriculture & aquaculture -> 2.3. Livestock farming
& ranching -> 2.3.2. Small-holder grazing, ranching or
farming
Ongoing Minority (50%) Causing/could
cause fluctuations
Low impact: 5
5. Biological resource use -> 5.1. Hunting & trapping
terrestrial animals -> 5.1.3. Persecution/control
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 Minority (50%) Slow, significant
declines
Low impact: 5
Conservation Actions in Place
© The IUCN Red List of Threatened Species: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
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(http://www.iucnredlist.org/technical-documents/classification-schemes)
Conservation Action in Place
In-place land/water protection
Conservation sites identified: Yes, over entire range
Occurs in at least one protected area: Yes
In-place education
Included in international legislation: Yes
Subject to any international management / trade controls: Yes
Conservation Actions Needed
(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
4. Education & awareness -> 4.3. Awareness & communications
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 -> 1.5. Threats
1. Research -> 1.6. Actions
2. Conservation Planning -> 2.1. Species Action/Recovery Plan
2. Conservation Planning -> 2.2. Area-based Management Plan
2. Conservation Planning -> 2.3. Harvest & Trade Management Plan
3. Monitoring -> 3.1. Population trends
3. Monitoring -> 3.3. Trade trends
3. Monitoring -> 3.4. Habitat trends
© The IUCN Red List of Threatened Species: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en
9
Additional Data Fields
Distribution
Estimated extent of occurrence (EOO) (km²): 2731029
Continuing decline in extent of occurrence (EOO): Yes
Lower elevation limit (m): 300
Upper elevation limit (m): 2,050
Population
Extreme fluctuations: Unknown
Population severely fragmented: No
Habitats and Ecology
Continuing decline in area, extent and/or quality of habitat: Yes
Generation Length (years): 9.7
Movement patterns: Not a Migrant
© The IUCN Red List of Threatened Species: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en
10
The IUCN Red List of Threatened Species™
ISSN 2307-8235 (online)
IUCN 2020: T92252480A92252486
Scope(s): Global
Language: English
The IUCN Red List Partnership
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.
THE IUCN RED LIST OF THREATENED SPECIES™
© The IUCN Red List of Threatened Species: Erythrocebus patas ssp. pyrrhonotus – published in 2020.
https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T92252480A92252486.en
11
Article
Full-text available
The classification of most mammalian orders and families is under debate and the number of species is likely greater than currently recognized. Improving taxonomic knowledge is crucial, as biodiversity is in rapid decline. Morphology is a source of taxonomic knowledge, and geometric morphometrics applied to two dimensional (2D) photographs of anatomical structures is commonly employed for quantifying differences within and among lineages. Photographs are informative, easy to obtain, and low cost. 2D analyses, however, introduce a large source of measurement error when applied to crania and other highly three dimensional (3D) structures. To explore the potential of 2D analyses for assessing taxonomic diversity, we use patas monkeys (Erythrocebus), a genus of large, semi‐terrestrial, African guenons, as a case study. By applying a range of tests to compare ventral views of adult crania measured both in 2D and 3D, we show that, despite inaccuracies accounting for up to ¼th of individual shape differences, results in 2D almost perfectly mirror those in 3D. This apparent paradox might be explained by the small strength of covariation in the component of shape variance related to measurement error. A rigorous standardization of photographic settings and the choice of almost coplanar landmarks are likely to further improve the correspondence of 2D to 3D shapes. 2D geometric morphometrics is, thus, appropriate for taxonomic comparisons of patas ventral crania. Although it is early to generalize, our results corroborate similar findings from previous research in mammals, and suggest that 2D shape analyses are an effective heuristic tool for morphological investigation of small differences. This article is protected by copyright. All rights reserved.
Technical Report
Full-text available
Patas monkey Erythrocebus patas, IUCN Red List of Threatened Species 2008, iucn.org
Article
Full-text available
Generation length (GL) is defined as the average age of parents of the current cohort, reflecting the turnover rate of breeding individuals in a population. GL is a fundamental piece of information for population ecology as well as for measuring species threat status (e.g. in the IUCN Red List). Here we present a dataset including GL records for all extant mammal species (n=5427). We first reviewed all data on GL published in the IUCN Red List database. We then calculated a value for species with available reproductive parameters (reproductive life span and age at first reproduction). We assigned to missing-data species a mean GL value from congeneric or confamilial species (depending on data availability). Finally, for a few remaining species, we assigned mean GL values from species with similar body mass and belonging to the same order. Our work provides the first attempt to complete a database of GL for mammals; it will be an essential reference point for all conservation-related studies that need pragmatic information on species GL, such as population dynamics and applications of the IUCN Red List assessment.
Article
This field guide begins with a checklist. The main part of the volume consists of entries for each species. Each entry provides information on common names, measurements, recognition, geographical distribution (plus map), habitat, diet, behaviour, adaptations and conservation status. Illustrations are also included. Brief notes are also provided on the African environment (physical, climate and vegetation) and palaeoecology (habitats and species). Finally a short section examines African wildlife conservation.
Article
Patas monkeys may be especially vulnerable to local extinction because they live in relatively small, female-philopatric groups at low densities and are strongly polygynous. We assessed a patas monkey population in Kenya's 9,700 km(2) Laikipia District over 25 years, using data collected in 1979-1981 and 1992-2004. The data were based on intensive observations of three study groups, "on the ground" counts, and surveys of Laikipia residents. In 1979-1981, a minimum of 415 patas monkeys lived in 14-15 groups. By 2000, the best estimate suggested 310-445 patas monkeys living in 13-17 groups over a greater surveyed area, suggesting that patas monkeys in Laikipia may have undergone a slight decline in numbers over time. Their distribution, however, was similar over time. The relative stability of this population has likely been the result of beneficial co-existence with large-scale cattle ranching. Outside Laikipia, substantial habitat alteration from rising human populations has coincided with the near disappearance of patas monkeys where they were previously more numerous. The small population in Laikipia, probably the largest remaining in Kenya, may therefore be critical to the continued existence of patas monkeys in that country and may be dependent on maintenance of large-scale ranches. Such land use provides patas monkeys with water and broad expanses of Acacia drepanolobium woodlands, the habitat to which patas are restricted in Laikipia.
Erythrocebus patas Patas Monkey (Hussar Monkey, Nisnas)
  • L A Isbell
Isbell, L.A. 2013. Erythrocebus patas Patas Monkey (Hussar Monkey, Nisnas). In: T.M. Butynski, J. Kingdon and J. Kalina (eds), The Mammals of Africa. Volume II: Primates, pp. 257-264. Bloomsbury Publishing, London.
The IUCN Red List of Threatened Species. Version 2020-2. Available at: www.iucnredlist.org
  • Iucn
IUCN. 2020. The IUCN Red List of Threatened Species. Version 2020-2. Available at: www.iucnredlist.org. (Accessed: 13 June 2020).
Die Formen der Gattung Erythrocebus
  • E Schwarz
Schwarz, E. 1927. Die Formen der Gattung Erythrocebus. Sitzungsberichte der Gesellschaft Naturforschender Freunde zu Berlin 1926: 24-31.