Uakari

TAXONOMY

Suborder: Haplorrhini Infraorder: Simiiformes Family: Pitheciidae Subfamily: Pitheciinae Genus: Cacajao Species: C. calvus, C. melanocephalus Subspecies: C. c. calvus, C. c. novaesi, C. c. rubicundus, C. c. ucayalii, C. m. melanocephalus, C. m. ouakary Other names: uacari; C. calvus: bald uakari, bald-headed uacari, red uakari, red-and-white uacari; witte oeakari (Dutch); ouakari chauve (French); cacajao, cacayao, huapo colorado, huapo rojo, uacaries, uacari blanco (Spanish); skallig kortsvansaparöd uakari, skallig uakari, vit uakari (Swedish); C. c. novaesi: Novaes’ bald-headed uacari; uacarí (Spanish); C. c. rubicundus: red bald-headed uacari; mono ingles, uacarí-vermelho (Spanish); C. c. ucayalii: Ucayali bald-headed uacari, Peruvian red uacari; C. melanocephalus: black uacari, black-headed uacari, Humboldt’s black-headed uacari; zwartkopoeakari (Dutch); ouakara à tête noire (French); mono chucuto, uacari-bicó, uacarí-preto (Spanish); svart uakari, svartansiktad kortsvansapa, svarthuvad uakari (Swedish).

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While some authors list several additional subspecies of uakari, as per Groves (2005), only four subspecies of C. calvus are considered here. C. melanocephalus is sometimes divided into two subspecies, C. m. melanocephalus and C. m. ouakary, and here both are considered at the subspecific level as per Hershkovitz (1987) for the sake of simplicity. Some authors also elevate the two subspecies of C. melanocephalus to full species level, however here they are not treated as such. In 2008, two additional species of uakari, C. ayresi (Aracá uakari) and C. hosomi (Neblina uakari) were described (Boubli et al. 2008). The common and generic names of the uakari species likely have their origin in indigenous Amazonian languages (Barnett 2004).

MORPHOLOGY

Medium-sized uakaris are the largest of the New World monkeys without a prehensile tail and are characterized by the presence of a short and bushy tail which is less than half to only one third of the head and body length of the animal (Fontaine 1981; Hershkovitz 1987; da Cunha & Barnett 1989; Barnett 2005; Norconk 2007). The muzzle is broad (Hershkovitz 1987). The main distinguishing characteristics between the two species of uakari are the head and the pelage. The C. calvus head ranges from bald to sparsely haired, while C. melanocephalus has plenty of hair (Barnett 2005). The profound lack or near lack of pigment in the face and head of C. calvus results in a reddish appearance of the face and head caused by the presence blood vessels near the surface of the skin (Hershkovitz 1987; Barnett 2005). The face of C. melanocephalus is black, and the head has blackish hair (Hershkovitz 1987; Barnett 2005). The pelage of C. melanocephalus is generally a rich and bright reddish-brown, with black head, neck, hands, and feet, while C. calvus can range among subspecies from reddish to orange and buffy to whitish or pale yellow (Hershkovitz 1987; Barnett 2005; A. Barnett pers. comm). C. m. ouakary has a gold-colored cape and C. m. melanocephalus has a black one (A. Barnett pers. comm.). The color differences between populations can be arranged on a geographic continuum; that is, they grade from one to another by location (Barnett 2005). This is well exhibited in C. calvus, where C. c. calvus is very pale, while C. c. novaesi is orange-buff, C. c. rubicundus is reddish, and C. c. ucayalii is reddish-orange (Hershkovitz 1987; Barnett & Brandon-Jones 1997). The ventrum is nearly bare (Barnett 2005). Both sexes have a sternal gland which might be involved in olfactory communication (Fontaine & DuMond 1977). In both species, the fur on the shoulders and anterior back is long, shortening by the midback, and in C. melanocephalus, the hair on the sides of the body can be up to 10 cm (3.9 in) long (Hershkovitz 1987; Barnett 2005). In general, in both species, males are larger and weigh more than the females but there are no differences in the pelage between males and females (Hershkovitz 1987; Barnett & Brandon-Jones 1997). C. melanocephalus head and body lengths average 41.4 cm (16.3 in) (male) and 38.9 cm (15.3 in) (female), while C. calvus average 45.6 cm (18.0 in) (male) and 44.0 cm (17.3 in) (female) (Hershkovitz 1987). Based on very small samples, male C. melanocephalus can weigh between 2.66 kg and 2.8 kg (5.9 and 6.2 lb), while C. calvus of both sexes can weigh between 2.75 and 3.45 kg (6.1 and 7.6 lb) (Ayres 1986 cited in Hershkovitz 1987). Uakaris are predominantly arboreal quadrupeds, most frequently walking, running, clamber-running, leaping and bridging in the upper and middle-upper levels of the forest canopy (Walker 1996; Walker & Ayres 1996; Boubli 1997a; Barnett 2005). Less frequently, arm-swinging is used, and on rare occasions, bipedal movement is seen (Boubli 1997a). In addition, uakaris will often leap or drop between supports during travel, a result of their relatively discontinuous forest habitat (Walker 1996; Walker & Ayres 1996; Boubli 1997a). While feeding, uakaris usually sit and while resting they will either sit or lie on their belly (Walker 1996). Uakaris are capable of swimming (Barnett 2008). Uakaris seasonally forage on the ground (Ayres 1986; Barnett 2008). In captivity, uakaris have lived into their mid-thirties (Weigl 2005).

ECOLOGY

C. melanocephalus are predominantly frugivorous but specialize in the seeds of hard-husked unripe fruits. For C. melanocephalus, the recorded diet at one study site comprised of 89% fruits, 5% flowers, 4% leaves and leaf parts, and 2% invertebrates (including ants, spiders, grasshoppers, katydids and roaches). The concentration on unripe fruits is unlike any unlike other neotropical frugivores, and is helped by special dentition and a chewing apparatus which allows it to use foods which are unavailable to other primates (Ayres 1989; 1990; Boubli 1999). Up to 120 species of plant are exploited as food with a few preferred species making up a significant proportion of the diet. The seeds of fruits are extremely important in the diet, comprising the majority of fruit feeding observations (Boubli 1999). The majority of these come from unripe fruits. Fruits are often bitten along their sutures, which require less force to puncture (Adrian Barnett pers. comm.). The known diets of C. calvus are similar to those recorded for C. melanocephalus and C. ouakary, with seeds of fruits predominating (67% of observations) followed by other parts of fruit (10%), flowers (6%), nectar, some insects (5%) and unidentified foods (4%) (Ayres & Johns 1987; Ayres 1989). Aquino & Encarnación (1999) noted C. c. ucayalii eating 53 plant species from 20 families, of which 46% were consumed for their seeds. Of these, 67% had thick heavy husks and were consumed in the immature state. In the dry season, Peruvian red uakaris will also eat bromeliad leaf bases, and also move to unflooded forest to feed on palm fruit as well as (unspecified) flowers and leaves (Aquino & Encarnación 1994; Aquino 1995). For C. ouakary, larvae of wasps and the eggs of turtles are also reported as being eaten on occasion, with wasp nests raided by the species (Barnett 1999; Barnett et al. 2005a; Barnett 2008). Almost one hundred species of plant are eaten by C. calvus (Ayres 1989). Uakaris sometimes descend to the ground during specific times of the year and forage for seeds and seedlings (Ayres 1989; Barnett & de Castilho 2000; Barnett 2008). When fruits are in short supply, leaves and pith are consumed (Barnett 2005; 2008). In addition, during periods of relative fruit scarcity, uakaris will actually increase the amount of ripe fruit pulp they consume because during periods of fruit abundance, they will focus on unripe seeds and other abundant foods as preferred resources (Boubli 1999). Uakaris are diurnal. The day of C. m. melanocephalus is spent resting (22%), traveling (27%), feeding (20%), and moving/foraging (31%). Over the course of the day, travel occurs most early and late in the day, resting peaks in the late morning or early afternoon, feeding is relatively constant, and moving/foraging is common in the morning and early afternoon (Boubli 1997a). The white uakari (C. c. calvus) begins its day at sunup and descends from the sleeping trees to feed. The troop will feed and move until noon with a period of rest around midday. In the mid-afternoon, the troop will resume feeding and moving and by dark, the group will have begun entering their sleeping site for the night (Ayres 1990). Uakaris are characterized by very large day ranges, traveling up to 4.4 km (2.7 mi) or even 5 km (3.1 mi) per day during fruiting. Annual averages are often lower; in one study with small sample sizes they averaged 2.3 km (1.4 mi) per day (Ayres 1989; Boubli 1997a; 1999). They travel quickly (Boubli 1997b). Some subspecies range even farther, with one estimate placing the day range of C. c. ucayalii at an average of 7.3 km (4.5 mi) (Leonard & Bennett 1995; 1996). Ranging distances are dependent on the state of food availability and during the high-water fruiting season distances traveled are farther than during the dry season, when they are considerably shorter (Ayres 1990). Home ranges of C. m. melanocephalus (minimum estimate of 10.53 km² (4.1 mi²)) are larger than those observed for C. calvus (5.0-5.5 km² (1.9-2.1 mi²)), but some estimates for C. c. ucayalii place home range at a very large 30 km² (11.6 mi²) however, often the area within the home range that is used the majority of the time is smaller, as is the case with C. calvus (2.5-3.0 km² (1.0-1.2 mi²)) (Ayres 1989; Leonard & Bennett 1996; Boubli 1997). Harpy eagles (Harpya harpya) are a potential and actual predator of uakaris (Leonard & Bennett 1996; Boubli 1997a; Barnett et al. 2005b). Other potential predators include ocelots (Felis pardalis), tayras (Eira barbara) and Boa constrictor snakes. Uakaris often react to perceived aerial threats, including bird species that are not predators, such as toucans (Boubli 1997a). In different locations, uakaris are sympatric with different primate species, but across their distribution, they can be sympatric with members of the genera Alouatta, Aotus, Callicebus, Chiropotes, Cebus, Lagothrix, Pithecia, and Saimiri (Leonard & Bennett 1996; Boubli 1999; 2002). In some cases, uakaris are found in association with other primates including spider monkeys (Ateles sp.), wooly monkeys (Lagothrix sp.), sakis (Chiropotes sp. & Pithecia sp.), capuchins (Cebus sp.), and squirrel monkeys (Saimiri sp.) (Leonard & Bennett 1996; Aquino 1988; 1998; Boubli 2002). Such associations might provide predator protection and foraging benefits (Leonard & Bennett 1996). Competition for food comes from species with dietary overlap with uakaris, such as macaws (Ara sp.), squirrels and sympatric primates such as squirrel monkeys and capuchins. Such overlap and levels of potential competition require quantitative assessment, but are probably low (Barnett 2005; Barnett et al. 2005a; Barnett 2008). Sleeping occurs high in the trees, normally 17 (55.8 ft) to around 40 meters (131.2 ft) up, with the troop distributed in different trees over about an acre, with only 6-7 individual uakaris per sleeping tree (Ayres 1990; Aquino 1998).

Content last modified: July 21, 2008

Written by Kurt Gron. Reviewed by Adrian Barnett.

Cite this page as: Gron KJ. 2008 July 21. Primate Factsheets: Uakari (Cacajao) Taxonomy, Morphology, & Ecology . <http://pin.primate.wisc.edu/factsheets/entry/uakari>. Accessed 2020 July 7.

SOCIAL ORGANIZATION AND BEHAVIOR

Uakari group size is extremely variable, from as small as a pair to a hundred individuals and perhaps as many as 200 individuals with many observations intermediate between the largest and smallest estimates and observations. Most groups appear to be < 70 individuals and significantly smaller groups are likely subdivisions of larger ones (Mittermeier & Coimbra-Filho 1977; Ayres & Johns 1987; Bartecki & Heyman 1987; Aquino 1988; Ayres 1990; Defler 1991; Heymann 1992; Boubli 1994; Barnett & Brandon-Jones 1997; Boubli 1997a; Aquino 1998; Defler 1999; Bennett et al. 2001; Bowler 2002; Ward & Chism 2003; Barnett et al. 2005a). Groups numbering over 100 individuals are the largest groups of any New World primate (Boubli 1994). Numbers are variable between populations as well, with some authors placing the maximum group size far lower, around 30 individuals (Barnett et al. 2000). This large variation in observed group size might be indicative of a fission-fusion type of social organization (Defler 1999). However, some long-term observations did not observe fluctuating group size or fission-fusion, while others recorded a seasonal dispersal of the larger groups into mating pairs and bachelor groups (Ayres 1990; Boubli 1997a; 1997b). Larger groups aggregate particularly at times of more abundant food but also potentially the result of other factors (Defler 1999; Aquino 1998). Some researchers have observed large groups breaking into smaller subunits during travel and during foraging, subunits that sometimes last for several days and some researchers postulate that perhaps there could be several levels of social organization within uakari groups (Ayres & Johns 1987; Bartecki & Heyman 1987; Ayres 1989; Heymann 1992; see also Grüter & Zinner 2004 for speculation). Groups are multi-male/multi-female and are usually composed of multiple adult males and females, subadults (including juveniles and infants) and group membership is roughly evenly divided between the sexes (Ayres 1989; Boubli 1997a; 1997b; Aquino 1998). However, bachelor male groups of up to 8 males have been seen in certain times of the year (Ayres 1990). The group is dispersed as it travels, and comes together at large food patches and during rest periods and members of subgroups can be spread as far as 1-2 km (0.6-1.2 mi) from one another (Ayres 1989; 1990; Boubli 1999). Contact within the group is maintained through calling (Boubli 1997b; 1999). In general, very little is known about the social structure of wild uakari troops. In the wild, if the group is disturbed one male has been seen to remain behind and vocalize in the direction of the intruder although what this means about the social structure of the troop remains to be clarified (Barnett et al. 2005a). It is suggested that wild uakari social organization is non-hierarchical (Barnett & Brandon-Jones 1997). However, a dominance hierarchy is seen in captive uakaris, maintained predominantly through fighting (Fontaine & DuMond 1977; Fontaine 1981). Further, in the wild, males have been seen aggressively interacting although again, the meaning of these interactions is ambiguous, and aggression appears to be very rare (Barnett et al. 2005a; Barnett 2008). During rest, grooming sometimes occurs and is initiated by female uakaris (Aquino 1998). In captivity, grooming is frequent and helps maintain friendly social relationships. However, most of the time individual uakaris are usually at least several meters from the nearest conspecific (Fontaine & DuMond 1977). Grooming is rarely seen in the wild, at least for C. m. ouakary (Barnett 2008). Aggression in captivity is signaled by branch shaking, rocking, breaking, carrying and dropping. It is also signaled by hind leg extension and rubbing, the bouncing of the hindquarters, strutting, and the urine-washing of the chest (Fontaine & DuMond 1977). Further, dominant individuals in captivity intervene in disputes between other group members (Fontaine & DuMond 1977). Tail-wagging is almost constant in uakaris (Boubli 1997a). Though Fernandes (1993) considers this to be a sign of alarm, Defler (2004) considers it a sign of contentment in C. m. ouakary, noting that an alarmed or fearful animal will curl its tail under its body, like a submissive dog. In captivity, play is seen not only involving sub-adults, but also between adult individuals (Fontaine 1981). Play is extensive in young wild C. m. ouakary (Barnett 2008).

REPRODUCTION

Both species of uakaris appear to have birth seasons or peaks. C. calvus sees a peak in births during the dry season, between October and November while C. melanocephalus has a birth season between March and April (Ayres 1986 cited in Norconk 2007; Ayres 1990; Boubli 1997a; Defler 2004; Barnett 2005). However, births can occur outside of the birth season and new evidence that C. m. ouakary might have two annual breeding peaks (Defler 2004; Barnett 2008). Wild births are single and in the wild and in captivity, the interbirth interval is estimated roughly at two years (Fontaine & DuMond 1977; Defler 2004; Barnett 2005). In captivity, females show their receptivity by directing their hindquarters at a male and raising their tail (Fontaine & DuMond 1977). Females are receptive only about 3 or 4 days per ovarian cycle (Fontaine & DuMond 1977). In captive individuals, copulation is usually dorso-ventral with the male behind the female although in at least one wild observation, face-to-face copulation was seen (Fontaine & DuMond 1977; Boubli 1997a). In the wild, copulation generally lasts less than two minutes (Ayres 1990). In captivity, post-copulation, genital sniffing and grooming follows (Fontaine & DuMond 1977). Gestation is approximately six months (Ayres 1990). Data about the age of reproductive maturity in uakaris is extremely limited but based on exceedingly small samples, males in captivity are reproductively successful at 6 years old while a single female was reproductively mature at 3 years old (Fontaine & DuMond 1977).

PARENTAL CARE

Almost all of the available information on parental care and infant development comes from a single semi-natural captive population of C. calvus in Florida observed over twenty years ago (see Fontaine & DuMond 1977; Fontaine 1981). Neither C. melanocephalus sub-species has ever been bred in captivity (Barnett 2005). Size at birth is at best 10% of that of the mother and the face and head are grayish and have hair (Fontaine 1981; Ayres 1990). All births occurred at night in an outdoor captive enclosure and for the first three months of life, the mother will reduce her interactions with the rest of the group (Fontaine & DuMond 1977; Fontaine 1981). The infant is not very active during its first month (Fontaine & DuMond 1977). Solid foods are first consumed around three months old. From birth until the third or fourth month, the infant is carried ventrally and to the side. After this age the infant rides on the mother’s back (Fontaine 1981). From three months old to one year old the face will start to transition from grey to pink, however at this time the head has thick hair, in contrast to the adults, a condition which persists through the second year of life. The baldness characteristic of C. calvus species develops in the third year (Fontaine & DuMond 1977; Fontaine 1981). In the sixth and seventh months of life, play starts with other infants. In the wild, while playing, juveniles vocalize a characteristic “hissing” sound (Boubli 1997a). Towards the end of the first year in captivity, the infant starts moving around independently (Fontaine 1981). Full weaning occurs in the 2nd year of life, is complete by two years old, and involves little weaning conflict (Fontaine 1981). In the wild, C. calvus infants nurse for 3-5 months, and start eating solid foods between 4 and 6 months of age. By one year old, the diet approximates the foods eaten by adult uakaris (Ayres 1990). Further, in C. melanocephalus, adult males are patient and tolerant of juveniles in the wild (Boubli 1997a).

COMMUNICATION

The wild contact calls of uakaris consist of “keeks,” “hics” and “chics” which are described as sounding roughly bird-like and are heard virtually non-stop (Boubli 1997a; 1997b; Ward & Chism 2003; Barnett 2005). Uakari vocalizations are best studied in captivity in C. calvus, and can be roughly separated into two categories, high- (“hic,” “chyook,” “chick,” “wee-ook,” “rhork,” “kreek,” “wa,” “kik” and “rhä”) and low-amplitude vocalizations (“purr,” “hiss,” and “keh”) (Fontaine 1981). In captivity, males use visual signals more than vocalizations, while females and immature individuals use vocalizations more than visual signals. Vocalizations are often contagious between individuals and are sometimes combined into sequences. “Hic,” “chyook,” and “chick” respectively are uttered in situations of increasing stimulus (Fontaine 1981). “Wa” vocalizations are loud and usually emitted during inter-individual fights and convey intense fear (Fontaine 1981; Ward & Chism 2003). “Kreek” and “rhork” convey less intense fear. “Purr,” “hiss” and “keh” vocalizations are uttered in friendly contexts. “Rhä” is heard during aggression and “kik” is motivated by fear during play (Fontaine 1981). Calls heard in the wild include the “purr” which is heard in affectionate situations, “ki-ki-kis” and “harsh screams” which are contact calls, “wai-wah-wah,” which is uttered during arousal, “chee-chee” which is a danger call, “screams” which are given by animals which are being punished, and the “harsh ehh” which is a play vocalization (Defler 2003 cited in Defler 2004). In the wild, tail-wagging commonly occurs at the same time as vocalization (Walker & Ayres 1996). A wagging tail likely communicates the well-being of the animal while a lowered tail communicates a tense situation to other uakaris (Defler 2004). In captivity, tail-wagging is seen in situations of general arousal (Fontaine 1981). In captivity, aggressive adult male visual signals include the single leg jerk, hindquarters bounce, branch slapping and arm raising, quadrupedal stand and stare, strut, branch rocking, and urine washing. Other agonistic visual signals include leg extension, arched back, piloerection, branch shaking, breaking, and dropping (Fontaine 1981). Further, the uakari draws on a canon of facial expressions which communicate a spectrum of meanings from agonism to affiliation to appeasement to fear as well as other meanings (see Fontaine 1981 for full description of facial expressions). Tactile patterns which the uakari uses to communicate through touch include allogrooming, body contact, contact aggression, and dorsal mounting, embracing, and sidling (Fontaine 1981). In the wild, visual signals include penile displays, piloerection, tail wag in upright position, tail-down, posterior display, and urine washing (Defler 2003 cited in Defler 2004). Olfactory communication in captivity consists of genital sniffing and licking, anal rubbing, rubbing substances in the fur, and urine washing (Fontaine 1981). The sternal glands present in both sexes might be involved in olfactory communication (Fontaine & DuMond 1977).

Content last modified: July 21, 2008

Written by Kurt Gron. Reviewed by Adrian Barnett.

Cite this page as: Gron KJ. 2008 July 21. Primate Factsheets: Uakari (Cacajao) Behavior . <http://pin.primate.wisc.edu/factsheets/entry/uakari/behav>. Accessed 2020 July 7.

INTERNATIONAL STATUS

For individual primate species conservation status, please search the IUCN Red List. Also search the current scientific literature for primate conservation status (overall as well as for individual species), and visit CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora).

Conservation information last updated in 2008 follows, for comparison: C. melanocephalus and its subspecies are listed as Least Concern; however, this may be in error and the result of observations of seasonal aggregations of animals feeding in flooded forests. The status of C. melanocephalus (and C. m. ouakary) should be reviewed (Adrian Barnett pers. comm.).

CONSERVATION THREATS & POTENTIAL SOLUTIONS

Threat: Human-Induced Habitat Loss and Degradation Logging has detrimental effects on uakaris and their habitat, even if the desired tree is not favored by uakaris. This is due to collateral felling of uakari food trees to help float commercial logs to points of sale, a reduction in selectivity of loggers resulting in food species being felled, and the alteration of the ecology of plant life in habitats precipitated by dams created by logged trees (Ayres 1986; 1990). Logging is in fact helped by the seasonal inundation of some uakari habitats as the water provides an easy way to extract logs by floating (Ayres 1990). Habitat degradation for agriculture also threatens uakari habitat as does the clearing of forests for pastureland (Heymann 1990). Further, the clearing of land for the establishment of ranches also has the potential to deplete uakari habitat (Barnett & da Cunha 1991). Illegal gold mining has also caused disturbances in uakari habitat, even in protected areas (da Cunha & Barnett 1989; Boubli 1994). One of the ways it does so is by damaging small watercourses by washing topsoil into them as well as by clearing of vegetation by burning it (Boubli 1997b). Several species of tree in the diet of the golden-backed uakari (C. m. ouakary) are also exploited commercially for timber (Barnett 2008). Threat: Harvesting (hunting/gathering) Across the genus Cacajao, the degrees of and the purposes for hunting uakaris are variable. For example, in Brazil, white uakaris (C. c. calvus) are not typically hunted for food, partially due to their anthropomorphic, or human-like, appearance. However in Peru, C. calvus is hunted intensively, for food as well as for skulls for the tourist souvenir trade (Mittermeier & Coimbra-Filho 1977; Ayres 1986; Bartecki & Heyman 1987; Aquino 1988). In Venezuela, hunting pressure is likely the most profound threat to C. melanocephalus, especially by illegal gold miners for which bushmeat is an important food source (Barnett & da Cunha 1991; Lehman & Robertson 1994). In addition, miners sometimes hire indigenous hunters to procure bushmeat (Boubli 1997b). Sometimes, the large numbers of uakari individuals occurring in one place make them easy to hunt from a canoe (Defler 2001). Commercial hunting also threatens uakaris and occurs for the procurement of animal protein in the diets of some communities (Heymann 1990; Barnett & da Cunha 1991). Uakaris are also hunted for use as bait, particularly for fish, turtle, or cats, and even in areas where they are not hunted for food (Mittermeier & Coimbra-Filho 1977; Barnett & da Cunha 1991). While in some areas, hunting has formerly focused on the largest primates for food, depletion of those populations can cause an increase in hunting of somewhat smaller primates including uakaris who had been previously unaffected (Ward & Chism 2003). Uakaris are also collected as pets, often as infants when their mothers are killed and sometimes specifically for this purpose (Aquino 1988; Ward & Chism 2003).

Threat: Pollution

Mercury, a byproduct of illegal mining sometimes makes its way into watercourses within uakari habitats and has the potential to adversely affect the health of the species (Lehman & Robertson 1994).

Threat: Intrinsic Factors

Bald uakaris have one of the highest rates of malarial infection in Amazonian primates. This infection rate might be attributable to their large group size and has the potential to have detrimental effects on their health (Davies et al. 1991).   Threat: Harvesting (hunting/gathering) Across the genus Cacajao, the degrees of and the purposes for hunting uakaris are variable. For example, in Brazil, white uakaris (C. c. calvus) are not typically hunted for food, partially due to their anthropomorphic, or human-like, appearance. However in Peru, C. calvus is hunted intensively, for food as well as for skulls for the tourist souvenir trade (Mittermeier & Coimbra-Filho 1977; Ayres 1986; Bartecki & Heyman 1987; Aquino 1988). In Venezuela, hunting pressure is likely the most profound threat to C. melanocephalus, especially by illegal gold miners for which bushmeat is an important food source (Barnett & da Cunha 1991; Lehman & Robertson 1994). In addition, miners sometimes hire indigenous hunters to procure bushmeat (Boubli 1997b). Sometimes, the large numbers of uakari individuals occurring in one place make them easy to hunt from a canoe (Defler 2001). Commercial hunting also threatens uakaris and occurs for the procurement of animal protein in the diets of some communities (Heymann 1990; Barnett & da Cunha 1991). Uakaris are also hunted for use as bait, particularly for fish, turtle, or cats, and even in areas where they are not hunted for food (Mittermeier & Coimbra-Filho 1977; Barnett & da Cunha 1991). While in some areas, hunting has formerly focused on the largest primates for food, depletion of those populations can cause an increase in hunting of somewhat smaller primates including uakaris who had been previously unaffected (Ward & Chism 2003). Uakaris are also collected as pets, often as infants when their mothers are killed and sometimes specifically for this purpose (Aquino 1988; Ward & Chism 2003). Threat: Pollution Mercury, a byproduct of illegal mining sometimes makes its way into watercourses within uakari habitats and has the potential to adversely affect the health of the species (Lehman & Robertson 1994). Threat: Intrinsic Factors Bald uakaris have one of the highest rates of malarial infection in Amazonian primates. This infection rate might be attributable to their large group size and has the potential to have detrimental effects on their health (Davies et al. 1991).

LINKS TO MORE ABOUT CONSERVATION

CONSERVATION INFORMATION

• No current links for Cacajao
• Links for all species

CONSERVATION NEWS

• New monkey species is already endangered  (New Scientist; January 19, 2008)
• Links for all species

ORGANIZATIONS INVOLVED IN Cacajao CONSERVATION

• Estacion Biologica Caparu

Content last modified: July 21, 2008

Written by Kurt Gron. Reviewed by Adrian Barnett.

Cite this page as: Gron KJ. 2008 July 21. Primate Factsheets: Uakari (Cacajao) Conservation . <http://pin.primate.wisc.edu/factsheets/entry/uakari/cons>. Accessed 2020 July 7.

REFERENCES

Aquino R. 1995. Conservacion de Cacajao calvus ucayalii en la Amazonia Peruana. Neotrop Prim 3(2):40-2. Aquino R, Encarnación F. 1999. Observaciones preliminaries sobre la dieta de Cacajao calvus ucayalii en el nor-oriente Peruano. Neotrop Prim 7(1):1-5. Aquino R. 1988. Preliminary survey on the population densities of Cacajao calvus ucayalii. Prim Conserv 9:24-6. Aquino R, Encarnación F. 1994. Primates of Peru. Prim Rep 40:1-127. Aquino R. 1998. Some observations on the ecology of Cacajao calvus ucayalii in the Peruvian Amazon. Prim Conserv 18:21-4. Ayres JM. 1989. Comparative feeding ecology of the uakari and bearded saki, Cacajao and Chiropotes. J Hum Evol 18:697-716. Ayres JM, Johns AD. 1987. Conservation of white uacaries in Amazonian várzea. Oryx 21(2):74-80. Ayres JM. 1986. The conservation status of the white uakari. Prim Conserv 7:22-6. Ayres JM. 1990. Scarlet faces of the Amazon. Nat Hist 99(3):32-41. Ayres JM. 1986. Uakaris and Amazonian flooded forest. PhD dissertation, University of Cambridge. 338p. Barnett AA. 2005. Cacajao melanocephalus. Mammal Spec 776:1-6. Barnett AA, de Castilho CV, Shapley RL, Anicácio A. 2005a. Diet, habitat selection and natural history of Cacajao melanocephalus ouakary in Jaú National Park, Brazil. Intl J Primatol 26(4):949-69. Barnett AA, Brandon-Jones D. 1997. The ecology, biogeography and conservation of the uakaris, Cacajao (Pitheciinae). Folia Primatol 68(3-5):223-35. Barnett AA, Borges S, de Castilho CV. 2000. Golden-backed uacari, Cacajao melanocephalus ouakary, in Jaú National Park, Amazonas, Brazil. Primate Eye 70:33-7. Barnett A, da Cunha AC. 1991. The golden-backed uacari on the upper Rio Negro, Brazil. Oryx 25(2):80-8. Barnett AA. 2004. The meanings of Cacajao and Uacari: folk etymology in neotropical primate taxonomy. Neotrop Prim 12(3):147-52. Barnett AA, Deveny A, Schiel V. 2005b. Report of a technical visit to Jaú National Park, Amazonas, 27 March-4 April 2005. Concord (CA):Akodon Ecological Consulting. 5p. Barnett AA, de Castilho CV. 2000. Report on a short study of the dry season feeding ecology and habitat preferences of the golden-backed uacari or bicó, Cacajao melanocephalus ouakary (Cebidae: Pitheciinae) on the lower Rio Jaú, Amazonas, Brazil. Concord (CA): Akodon Ecological Consulting. 18p. Barnett AA. 1999. Report on a short study of the wet season feeding ecology and habitat preferences of the golden-backed uacari or bicó, Cacajao melanocephalus ouakary, in Jaú National Park, Brazil. Concord (CA): Akodon Ecological Consulting. 8p. Barnett AA. 2008. Report on fieldwork conducted in Jaú National Park, Amazonian Brazil, between January and December 2007 on the diet, habitat preferences and conservation ecology of the golden-backed uacarí, Cacajao ouakary (Pitheciidae, Primates). Concord (CA): Akodon Ecological Consulting. Bartecki U, Heyman EW. 1987. Sightings of red uakaris, Cacajao calvus rubicundus, at the Rio Blanco, Peruvian Amazon. Prim Conserv 8:34-6. Bennett CL, Leonard S, Carter S. 2001. Abundance, diversity, and patterns of distribution of primates on the Tapiche River in Amazonian Peru. Am J Primatol 54(2):119-26. Boubli JP. 1994. The black uakari monkey in the Pico da Neblina National Park. Neotrop Prim 2(3):11-2. Boubli JP. 1997a. Ecology of the black uakari monkey, Cacajao melanocephalus melanocephalus, in Pico da Neblina National Park, Brazil. PhD dissertation, University of California, Berkeley. Boubli JP. 1999. Feeding ecology of black-headed uacaris (Cacajao melanocephalus melanocephalus) in Pico da Neblina National Park, Brazil. Intl J Primatol 20(5):719-49. Boubli JP. 1993. Southern expansion of the geographical distribution of Cacajao melanocephalus melanocephalus. Intl J Primatol 14(6):933-7. Boubli JP. 1997b. A study of the black uakari, Cacajao melanocephalus melanocephalus, in the Pico da Neblina National Park, Brazil. Neotrop Prim 5(4):113-5. Boubli JP. 2002. Western extension of the range of bearded sakis: a possible new taxon of Chiropotes sympatric with Cacajao in the Pico da Neblina National Park, Brazil. Neotrop Prim 10(1):1-4. Boubli JP, da Silva MNF, Amado MV, Hrbek T, Pontual FB, Farias IP. 2008. A taxonomic reassessment of Cacajao melaocephalus Humboldt (1811), with the description of two new species. Intl J Primatol 29:723-41. Bowler M. 2002. The ecology and conservation of the red uakari monkey Cacajao calvus ucayalii in the Yavari valley of Peru [abstract]. Prim Eye 79:3-4. da Cunha AC, Barnett A. 1989. Project uakari: first report-preliminary survey. Part one-zoology. Rio de Janeiro: Pronatura. 108p. Davies CR, Ayres JM, Dye C, Deane LM. 1991. Malaria infection rate of Amazonian primates increases with body weight and group size. Funct Ecol 5(5):655-62. Defler TR. 2001. Cacajao melanocephalus ouakary densities on the lower Apaporis River, Colombian Amazon. Prim Rep 61:31-6. Defler TR. 1999. Fission-fusion in the black-headed uacari (Cacajao melanocephalus) in eastern Colombia. Neotrop Prim 7(1):5-8. Defler TR. 1991. Preliminary observations of Cacajao melanocephalus Humboldt, 1811 (Primates, Cebidae) in Colombia. Trianea 4:557-8. Defler TR. 2003. Primates de Colombia. Bogotá: Conservación Internacional Colombia. Defler TR. 2004. Primates of Colombia. Bogotá: Conservation International. 550p. Fernandes MEB. 1993. Tail-wagging as a tension relief mechanism in Pithecines. Folia Primatol 61:52-6. Fontaine R, DuMond FV. 1977. The red ouakari in a seminatural environment: potentials for propagation and study. In: Rainier III (Grimaldi) Prince of Monaco, Bourne GH, editors. Primate conservation. New York: Academic Pr. p167-236. Fontaine R. 1981. The uakaris, genus Cacajao. In: Coimbra-Filho A, Mittermeier RA, editors. Ecology and behavior of neotropical primates. Rio de Janeiro: Academic Brasileira de Ciências. p 443-93. Groves C. 2005. Order primates. In: Wilson DE, Reeder DM, editors. Mammal species of the world: a taxonomic and geographic reference, third edition, volume 1. Baltimore (MD): Johns Hopkins U Pr. p 111-84. Grüter CC, Zinner D. 2004. Nested societies. Convergent adaptations of baboons and snub-nosed monkeys? Prim Rep 70:1-98. Hershkovitz P. 1987. Uacaries, new world monkeys of the genus Cacajao (Cebidae, Platyrrhini): a preliminary taxonomic review with the description of a new subspecies. Am J Primatol 12(1):1-53. Heymann EW. 1990. Further field notes on red uacaris, Cacajao calvus ucayalii, from the Quebrada Blanco, Amazonian Peru. Prim Conserv 11:7-8. Heymann EW. 1992. The red uakari (Cacajao calvus ucayalii): some field observations and speculations on a little-known species [abstract]. Prim Eye 47:6-7. Lehman SM, Robertson KL. 1994. Preliminary survey of Cacajao melanocephalus melanocephalus in southern Venezuela. Intl J Primatol 15(6):927-34. Leonard S, Bennett C. 1996. Associative behavior of Cacajao calvus ucayalii with other primate species in Amazonia Peru. Primates 37(2):227-30. Leonard S, Bennett C. 1995. Behavioral ecology study of red uakari, Cacajao calvus ucayalii, in northeastern Peru. Neotrop Prim 3(3):84. Mittermeier RA, Coinbra-Filho AF. 1977. Primate conservation in Brazilian Amazonia. In: Rainier III (Grimaldi) Prince of Monaco, Bourne GH, editors. Primate conservation. New York: Academic Pr. p 117-66. Norconk MA. 2007. Sakis, uakaris, and titi monkeys: behavioral diversity in a radiation of primate seed predators. In: Campbell CJ, Fuentes A, MacKinnon KC, Panger M, Bearder SK, editors. Primates in perspective. New York: Oxford U Pr. p 123-38. Peres CA. 1997. Primate community structure at twenty western Amazonian flooded and unflooded forests. J Trop Ecol 13(3):381-405. Silva JS Jr., Martins ES. 1999. On a new white bald uakari population in southwestern Brazilian Amazonia. Neotrop Prim 7(4):119-21. Walker SE. 1996. The evolution of positional behavior in the saki-uakaris (Pithecia, Chiropotes, and Cacajao). In: Norconk MA, Rosenberger AL, Garber PA, editors. Adaptive radiations of neotropical primates. New York: Plenum Pr. p 335-67. Walker SE, Ayres JM. 1996. Positional behavior of the white uakari (Cacajao calvus calvus). Am J Phys Anth 101(2):161-72. Ward NS, Chism J. 2003. A report on a new geographic location of red uakaris (Cacajao calvus ucayalii) on the Quebrada Tahuaillo in northeastern Peru. Neotrop Prim 11(1):19-22. Weigl R. 2005. Longevity of mammals in captivity; from the living collections of the world. Stuttgart (DE): E. Schweizerbartsche. 214 p. Whitehead M. 1984. Howler monkeys (Alouatta spp.) and uakaris (Cacajao spp.) in captivity and the field: a review with reference to experiences at Twycross zoo, U.K. Proc Symp Asso Brit Wild Anim Keep 8:5-21.

Content last modified: July 21, 2008

IMAGES

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	Cacajao calvus Photo: Primates in Art & Illustration
	Cacajao calvus calvus Photo: Luiz Claudio Marigo
	Cacajao calvus calvus Photo: Luiz Claudio Marigo
	Cacajao calvus calvus Photo: Luiz Claudio Marigo
	Cacajao calvus rubicundus Photo: Roy Fontaine
	Cacajao calvus rubicundus Photo: Roy Fontaine
	Cacajao calvus rubicundus Photo: Roy Fontaine
	Cacajao calvus rubicundus Photo: Roy Fontaine
	Cacajao calvus rubicundus Photo: Roy Fontaine
	Cacajao calvus rubicundus Photo: Roy Fontaine
	Cacajao melanocephalus Photo: Luiz Claudio Marigo
	Cacajao melanocephalus Photo: Luiz Claudio Marigo
	Cacajao melanocephalus Photo: Luiz Claudio Marigo