Erythrocebus patas (Schreber, 1774)

Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Cercopithecidae, Handbook of the Mammals of the World – Volume 3 Primates, Barcelona: Lynx Edicions, pp. 550-755 : 671-672

49.

Patas Monkey

Erythrocebus patas

French: Patas / German: Husarenaffe / Spanish: Mono patas

Other common names: Hussar Monkey, Military Monkey, Red Guenon; Air Patas/Air Red Monkey (villiersi), Blue Nile Hussar/Dancing Red/Eastern Patas Monkey (pyrrhonotus), lkoma/Southern Patas Monkey (baumstarki), West African Red / Western Patas Monkey (patas)

Taxonomy. Simia patas Schreber, 1774 ,

Senegal .

Although considered monotypic by most experts, several distinct subspecies have been described, distinguished mainly by slight differences in facial coloration and pattern. Some this variation, has been shown to be related to female reproductive physiology. In late pregnancy, the nose becomes white, black temporal lines disappear, and the face becomes light gray. These changes persist until c.45 days postpartum. Nevertheless, subspecieslikely do exist, as described below. At least one incidence of hybridization with a Chlorocebus aethiops pygerythrus has been reported in captivity. A fourth subspecies (villiersi) named by Dekeyser in 1950 is recognized by some. It occurs in Niger from Air and north of the bend of the Niger River. Clear demarcation of distributions of these possible subspecies is still unclear. Additional studies are needed. Three subspecies recognized.

Subspecies and Distribution.

E.p.patasSchreber,1774—sub-SaharanAfricafromSMauritaniaandSenegaltoChadandCentralAfricanRepublic;isolatedpopulationsinhabittherockyAirMassifofNNigerandtheEnnediMassif,Chad.

E.p.baumstarkiMatschie,1905—NCTanzania(SerengetiandAthiPlainsandtheWsideofMt.Kilimanjaro),butthedistributionisnotwelldocumented.

E. p. pyrrhonotus Hemprich & Erhenburg, 1829 — Sudan (N to Nubia), South Sudan, W Ethiopia, N DR Congo, N Uganda, and Kenya. Introduced into south-western Puerto Rico in the Caribbean Islands.

Descriptive notes. Head-body 60-87.5 cm (males) and 48-52 cm (females), tail 63— 72 cm (males) and 48-55 cm (females); weight 7-13 kg (males) and 4-7 kg (females). The Patas Monkey has substantial sexual dichromatism and dimorphism. Both sexes are reddish-brown above, with underside, rump, neck, chin, inner surfaces of limbs, and outer surfaces of lower limbs white in males, and fawn in females and juveniles. In infancy, crown hairs are mostly black. These begin to change at c.5-6 weeks of age. By 7-8 weeks, crown has the normal adult coloring. Adult males have a shaggier, more brightly contrasting coat, with russet tail, hindquarters, and crown, and they often develop a grayish shoulder mane with age. Females and juveniles are often the color of dry grass, with shades of fawn, russet, and gray, making them difficult to see in their savanna habitats. In adulthood, males can be twice the size of females, with some exceptional individuals weighing up to 20 kg. The nominate “Western Patas Monkey ” (E. p. patas ) has a pink face and a dark nasal spot, but more generally, its face ranges from pink through dirty white to black with a variable pattern, short cheek fringes, a white moustache, and a black band across the forehead extending to ears. Penis is red, and scrotum is blue. Ischial callosities are yellowish-white or grayish-white, and separated in both sexes. The status of subspeciesis still debated. Of note, the “Southern Patas Monkey ” (E. p. baumstarki) has been described as a “pallid Serengeti isolate,” while the “Eastern Patas Monkey ” (E. p. pyrrhonotus) is said to have a blackish face and white nose. Some recognize another subspecies, villiersi, which differs from the Western Patas Monkey only in its smaller size. Further study with a more detailed description and diagnosis is needed to determine whether this is indeed a fourth subspecies.

Habitat. Dry, open Acacia woodland savanna, semi-desert, and grassland. The Patas Monkey is mainly terrestrial and may also be found in volcanic rocky outcrops and woodland-grassland margins. They can live at elevations of up to 1900 m, although they are usually found in lower elevations.

Food and Feeding. Patas Monkeys are omnivores, eating a wide variety offruits , grass seeds, bulbs, leaves, new shoots, berries, flowers, tamarind beans, fungi, and bird eggs. They use many Acacia (Fabaceae) tree parts (fruits, galls, leaves, and gums). Some populations have 20% gum in their diets. Animal prey is also an important part of the diet of the Patas Monkey. This can include many arthropods, lizards, and nestling birds. Grassitself is rarely eaten. They eat prickly pear cactus ( Opuntia , Cactaceae ) that has been introduced to Kenya. Patas Monkeys need to drink daily, and they visit rivers, rock pools, waterholes, or puddles in the dry season. Groups occasionally raid cultivated areas. Varying availabilities of cultivated crops and insects result in great seasonal changes in their diet. In general, Patas Monkeys avoid large, tough foods, preferring instead small fruits or berries. The infrequent need for cutting and food preparation corresponds to their relatively small incisors.

Breeding. Female Patas Monkeys have a 30day reproductive cycle. They show no evidence of a sexual swelling during the periovulatory period, which lasts for ¢.3-6 days (range 1-10 days). The interbirth interval is c.1 year, which is shorter than would be expected for a monkey of its body mass. The 2-5month conception period tends to be seasonal and synchronized within the group. Typically, conception occurs in the wet season (summer), and births occur in the dry season (winter). In northern Cameroon, most mating takes place in the wet season and resulting births occur in late December to mid-February in the dry season. Timing varies geographically and is subjectto changes in the environment. One measure of female proceptivity is the unmistakable behavior ofsoliciting copulation by crouching in front of a male and exhaling into her cheek pouches. Despite this display, the female’s behavior does not usually appear to influence copulation rates of individual males. As seen in many other primate species, copulations tend to occur in early-to-late morning; copulations at mid-day and beyond are uncommon. During late pregnancy, the normally black nose of the female turns white, and the remainderof the face becomeslight gray, before ultimately reverting to its natural coloration c.45 days post-partum. One dark brown or blackish offspring is born after a gestation of 167 days. Births are typically diurnal, unlike most other monkeys. This is considered part of the Patas Monkey’s anti-predator strategy. As a result, several births have been witnessed and fully described by researchers. The entire labor and delivery process is fairly short (less than one hour), and the mothertypically places her newborn on the grass while eating the placenta. Juveniles are light brown with a pink face and are carried ventrally. The juvenile phase is short, with sexual maturity reached at three years or even earlier for females and 4-5 years for males. Individuals may live c.30 years in captivity.

Activity patterns. Patas Monkeys are diurnal and mainly terrestrial. Although they can easily climb trees when alarmed, they usually rely on their speed on the ground to escape from danger. Their relatively robust forelimb bones are well adapted for living a terrestrial lifestyle. They spend ¢.60% of their time on the ground, and a full 90% of their feeding time is on the ground. They use digitigrade hand and foot postures while walking, which helps increase stride length. Consequently, the Patas Monkey is generally considered to be the fastest primate. Nonetheless, they cannot outrun some of their predators (e.g. Cheetahs, Acinonyxjubatus), so they have a finely tuned system of vigilance and cryptic coloring to aid in predator avoidance. When traveling on the ground, Patas Monkeys tend to remain relatively silent. Daily movement may vary from 500 m to 12,000 m, and the group often splits before sunset. They rarely begin moving before 07:00 h and usually stop moving for the day by 19:00 h.

Movements, Home range and Social organization. Average group size of the Patas Monkey is 15, although most mixed-sex groups have 20-51 individuals. The home range is large (e.g. 51-8 km? for one group of 31 individuals), but all-male groups can have twice the home range size of mixed-sex groups. During the night, a group can spread out over as much as 25 ha. Such large home ranges and expansive sleeping patterns serve a protective role against predators but also aid in better exploitation of the habitat. Female Patas Monkeys remain in their natal group throughout their lives, while males disperse at maturity. They may then live alone, as extragroup males, or become the sole resident male of a female group. Their social system is not representative of their mating system; one-male groups are common, but this does not represent a harem unit. During the mating season, other adult males that normally live alone or in “bachelor” groupsjoin female groups. For about one month, mating occurs in a rather promiscuous manner; the original resident male does not have an advantage. Some mate guarding is occasionally observed, and there is often fighting among males associated with the mating season. Despite these fights, a definitive hierarchy among males is rarely identified. Adult males engage in jumping and calling as common alarm behaviors to distract predators, thus allowing females and young to escape danger. The role of adult males in an infant's life seems to vary according to study site. Some researchers report that males are often scarce in the group, resulting in an infant being several months old before it is made aware of their presence. Others report keen watchfulness on the part of adult males. In all cases, however, allomaternal behavior is regularly seen. In fact, underfield conditions,it can be difficult to identify which infants belong to which adult females.

Status and Conservation. CITES Appendix II. Classified as Least Concern on The IUCN Red List. The subspecies have not been assessed. The Patas Monkeyis listed as Class B in the African Convention on the Conservation of Nature and Natural Resources. It remains widespread and relatively common in parts of its distribution, although it is normally found at low population densities. Although their optimum density is estimated to be c.1-5 ind/km?, one study reported as few as 110 Patas Monkeys in 311 km? In Kenya, the current distribution is only 54% of the known historic (pre-1995) distribution. Drought and conversion ofsuitable habitat into farmland are growing threats. In fact, there has been a marked decrease in numbers of Patas Monkeys in parts of their range, because of habitat loss from increasing desertification. This results from unsustainable land-use practices, such as overgrazing by cattle and clearing of savanna land for crops. The resulting proximity to farmland leads to predictable crop-raiding and retaliatory persecution by farmers. Patas Monkeys are occasionally hunted by humans for meat (which was long believed by locals to cure leprosy). This has apparently led to a further decline in their numbers; Nigerian hunters report that Patas Monkeys were much more common 15-20 years ago. At the species level, the Patas Monkeyis known to occur in 37 protected areas: Pendjari and West of the Niger national parks in Benin; West of the Niger National Park in Burkina Faso; Bénoué, Bouba-Ndjida, Kalamaloué, and Waza national parks in Cameroon; Zakouma National Park in Chad; Abuko Nature Reserve and Kiang West National Park in Gambia; Bui, Digya, Mole national parks and Kogyae Strict Nature Reserve in Ghana; Comoé National Park in Ivory Coast; West of the Niger National Park in Niger ; Cross River and Kainji Lake national parks, Bagale Hills, Igangan Ohosu, and Oban Hills forest reserves, Borgu, Kwiambana, Mutum Biya, and Yankari game reserves, and Old Oyo and Upper Ogun reserves in Nigeria; Basse Casamance, Niokolo-Koba, and Djoudj national parks in Senegal; Dinder National Park in South Sudan; Serengeti National Park and Grumeti and Tkorongo game reserves in Tanzania; Keran, Koué, and Malfacassa reserves in Togo; and Kidepo Valley and Murchison Falls national parks in Uganda. Many Patas Monkeys also occur outside protected areas. The Laikipia District in Kenya is said to have the largest population, and they are routinely found in many unprotected areas of Nigeria and Sierra Leone, where bushmeat hunting remains a threat. Therefore, while the Patas Monkey is listed as Least Concern, they should be monitored in areas that are not protected; growing human populations and threatening activity may result in local risks of population decline. Of particular concern is that the Southern Patas Monkey of Tanzania declined by ¢.33% from 1995 through 2009. Their area of occurrence has decreased from 30,500 km? to 19,000 km? and population numbers are thoughtto be less than 900 individuals, perhaps even less than 150 individuals. Urgent conservation action is required for this subspecies.

Bibliography. Anadu et al. (1988), Bolwig (1963), Carlson & Isbell (2001), Chism & Isbell (2003), Chism & Rogers (1997), Chism & Rowell (1986, 1988), Chism, Olson & Rowell (1983), Chism, Rowell & Olson (1984), Dekeyser (1950), Enstam et al. (2002), Gonzalez-Martinez (1998), Groves (2001), Hall (1965, 1967), Hall & Goswell (1964), Hall & Mayer (1967), Hall et al. (1965), Harding & Olson (1986), Hylander (1975), Isbell (1998), Isbell & Chism (2007), Isbell & Pruetz (1998), Isbell, Pruetz, Lewis & Young (1998, 1999), Isbell, Pruetz & Young (1998), de Jong, Butynski, Isbell & Lewis (2009), de Jong, Butynski & Nekaris (2008), Kimura (2002), Kingdon, Butynski & de Jong (2008), Loy (1975, 1981, 1989a, 1989b, 1989c), Loy & Loy (1977), Loy, Argo et al. (1993), Loy, Lavelle et al. (1993), Matsubayashi et al. (1978), Muroyama (1994), Nakagawa (1989, 1992, 1999, 2000a, 2000b, 2003), Nakagawa et al. (2003), Ohsawa etal. (1993), Olson & Chism (1984), Palmer et al. (1981), Pruetz & Isbell (2000), Rowell (1975, 1988), Rowell & Chism (1986), Struhsaker & Gartlan (1970), York & Rowell (1988).

Figures

49. Patas Monkey (Erythrocebus patas), 50. Grivet Monkey (Chlorocebus aethiops), 51. Tantalus Monkey (Chlorocebus tantalus), 52. Green Monkey (Chlorocebus sabaeus), 53. Malbrouck Monkey (Chlorocebus cynosuros), 54. Vervet Monkey (Chlorocebus pygerythrus), 55. Bale Mountains Monkey (Chlorocebus djamdjamensis), 56. L’Hoest’s Monkey (Allochrocebus lhoesti), 57. Preuss’s 9 Monkey Allochrocebus (null), 58. Sun-tailed Monkey (Allochrocebus solatus)

Subspecies and Distribution. E.p.patasSchreber,1774—sub-SaharanAfricafromSMauritaniaandSenegaltoChadandCentralAfricanRepublic;isolatedpopulationsinhabittherockyAirMassifofNNigerandtheEnnediMassif,Chad. E.p.baumstarkiMatschie,1905—NCTanzania(SerengetiandAthiPlainsandtheWsideofMt.Kilimanjaro),butthedistributionisnotwelldocumented. E. p. pyrrhonotus Hemprich & Erhenburg, 1829 — Sudan (N to Nubia), South Sudan, W Ethiopia, N DR Congo, N Uganda, and Kenya. Introduced into south-western Puerto Rico in the Caribbean Islands.