Cebus olivaceus Schomburgk 1848
Creators: name: Russell A. Mittermeier
name: Anthony B. Rylands
name: Don E. Wilson
Publisher: name: Lynx Edicions
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Primates
Cebidae
Cebus
Cebus olivaceus

description: 20.
Guianan Weeper Capuchin
Cebus olivaceus
French: Sapajou pleureur / German: Brauner Kapuzineraffe / Spanish: Capuchino oliva
Other common names: \Wedge-capped Capuchin; Chestnut Weeper Capuchin (castaneus), Weeper Capuchin (olivaceus)
Taxonomy. Cebus olivaceus Schomburgk, 1848,
Venezuela, southern foot of Mount Roraima, Bolivar State, (c.4° 57° N, 61° 01° W), Venezuela, elevations 3100 feet (945 m).
P. Hershkovitz in 1949 listed five forms that he “provisionally recognized” as subspecies of a monotypic weeper capuchin, C. nigrivittatus, named by Wagner in 1848. Although the name nigrvittatus was used for the Guianan Weeper Capuchin through the 1970s,J. G. Robinson pointed out that in 1941 B. von Pusch combined Saimiri and Cebus, resulting in nigrivittatus being a secondary homonym due to the prior description of the squirrel monkey Chrysothrix nigrivittatta by Wagner in 1848 (a junior synonym of Saimiri sciureus). The name for the Guianan Weeper Capuchin thus became C. olivaceus. C. P. Groves in 2001 did not consider any of the subspecies valid and concluded that C. olivaceus was monotypic. A phylogenetic analysis of C. olivaceus byJ. Boubli and co-workers in 2012 largely confirmed the conclusion of Groves, except for one specimen from Guyana that could be distinguished as a distinct taxon;it diverged from the C. olivaceus ¢.700,000 years ago. This was ascribed to castaneus as listed by Hershkovitz in 1949. Its type locality is Cayenne, French Guiana, and it was considered to be the weeper capuchin of Guyana by G. Tate in 1939. Only one specimen was included in the analysis, but with further samples, castaneus may prove to be a distinct species. Two subspecies recognized.
Subspecies and Distribution.
C.o.olivaceusSchomburgk,1848—mightberestrictedtotheVenezuelanAmazonBasinfromtheupperRioOrinoco,andthroughouttheOrinocosavannaabovethemouthoftheRioMeta,asfarNandWastheSierradePerijaandtheVenezuelanC.o.dela C.o. (C.o. Range), to the left bank of the Rio Essequibo in W Guyana, in forests of the Guiana Shield; distributional limits separating the two subspecies are not well known. C. o. castaneus 1. Geoffroy Saint-Hilaire, 1851 — Guianas (possibly from the Rio Essequibo in Guyana E through Suriname and French Guiana) and N Brazil, where its distributional limits are not well known but are possibly marked by the rios Negro and Branco and Catrimani (right bank affluent of the Rio Branco) in the W, the Rio Amazonas in the S, and the Atlantic coast in the E, and it also occurs on Caviana and Mexiana Is in the estuary of the Rio Amazonas.
Small numbers introduced as pets are now feral on Margarita I off the Venezuelan coast.
Descriptive notes. Head-body 37-46 cm, tail 45-55 cm; weight 3.4-2 kg (males) and 2.3-3 kg (females). Male Guianan Weeper Capuchins are ¢.19-5% larger than females. It is a large, heavy-set, gracile/untufted species with long limbs and relatively coarse, shaggy fur. Pelage is brown with black-agouti banding on flanks, limbs, and tail. Hands, feet, and tailtip tend to be darkened. Underside tends to be dark. Lighter areas are light gray-brown,restricted to face and forehead and setting off a dark brown, sharp, Vshaped crown cap; the point of the “V” is connected to a thin umber stripe that runs down the center of the face to the nose. The face is naked and normally pink. The “Weeper Capuchin” (C. o. olivaceus) is mainly dark brown or reddish with black on the extremities and buffy-white cheeks. In the “Chestnut Weeper Capuchin” (C. o. castaneus), the black triangle on the crown is narrow, and the rest of the head is yellowish-white but more reddishchestnut above the ear and nape. Upperparts of the body and limbs are reddish chestnut, and shoulders and fronts of arms above the elbows are pale yellow. Hands and feet are blackish. The tail is blackish brown with gray tipped hairs on the dorsal surface.
Habitat. Primary rainforest, evergreen, and gallery forest from sea level to 2000 m; rarely in dry deciduous forest and shrub woodland. All levels of the forest are used by the Guianan Weeper Capuchin, although the middle and understory are preferred. Groups occasionally forage and play on the ground. In Suriname, the Chestnut Weeper Capuchin is almost entirely restricted to the interior, and like bearded sakis (Chiropotes) and spider monkeys (Ateles), it just enters the old coastal plain in a small part of western Suriname. Whereas the Guianan Brown Capuchin (Sapajus apella) is more of a habitat generalist in the Guianas, the Chestnut Weeper Capuchin is mostly restricted to high terra firma rainforest and is rarely or never seen in liana forest, pina (Euterpe) forest, and mountain savanna forest. An important study site for the Weeper Capuchin is Hato Masaguaral, a cattle ranch in the Llanos (savanna plains) of central Venezuela, a mosaic of grassland, palm savanna, shrub woodland, and gallery forest. The forest there is seasonal semi-deciduous dry forest, with annual rainfall of ¢.1450 mm, most of which falls during the wet season (May-October). Weeper Capuchins have also been studied at Hato Pinero 60 km south of Hato Masaguaral. Although physiognomically similar, the floristic composition of forests at each site is very different. Only 34 of 116 tree species occur at bothsites, and those that are shared occur in very different densities. Of 79 tree species in the diet of Weeper Capuchins, only 15 (19%) are eaten at both Masaguaral and Pinero.
Food and Feeding. In a detailed study of the diet of Weeper Capuchins at Hato Masaguaral by Robinson in the late 1970s, plant material accounted for 55% of all feeding records and animal prey 33% (in 12% ofthe records the food item was not identified). Fruit, largely fleshy and mostly ripe, was the main item of plant origin (46%) from more than 50 species in 30 families, the most important Rubiaceae and Moraceae. Fig trees (Ficus pertusa and FE. trigonata, Moraceae) produce fruit asynchronously and were a staple in most months of the year. Large seeds were not ingested, but most small ones were, and were defecated intact. Seeds of Coccoloba (Polygonaceae) and Zanthoxylum (Rutaceae) were chewed and crushed. Weeper Capuchins sometimes ate grass seeds. In the middle of the dry season (March-April), palm fruits (Copernicia, Arecaceae) were picked unripe and eaten while the seed wasstill soft. Hard fruits such as those of Sterculia apetala (Sterculiaceae) and Hymenaea courbaril (Fabaceae) were pounded to open them. They also ate buds,leaves, and shoots but mostly just chewed them and then spat out the fibrous material, perhaps mainly to get water. This was common in the dry season and included rachis (central stem) of Copernicia fronds. When rachis of young fronds first appeared in the crown, Weeper Capuchins would ingest them, but older fronds were chewed and spat out. Flowers were rarely eaten, but those of the epiphytic cactus Hylocereus polyrhizus were favored. Large male Weeper Capuchins, in particular, sometimes pulled up sapling Cochlospermum vitifolium (Bixaceae) and ate the roots. Weeper Capuchins eat freshwater snails (Pomacea), arthropods (spiders, cockroaches, mantids, stick insects, termites, grasshoppers, cicadas, scale insects, caterpillars, beetle grubs, ants, especially Cephalotes, and millipedes), frogs, frog eggs, iguanas, birds (including nestlings and eggs), and Red-tailed Squirrels (Sciurus granatensis) when they can catch them. They search for prey in litter, palm crowns, green and dried palm fronds, along branches, dead wood, and green and dead leaves. They also prey on wasp nests and eat larvae, pupae, and adults. Bird eggs eaten included those of rufous-vented chachalaca (Ortalis ruficauda), green ibis (Mesembrinibis cayennensis), red-legged tinamou (Crypturellus erythropus), white-tipped dove (Leptotila verreauxi), greater ani (Crotophaga major), and hoatzin (Opisthocomus hoazin). They eat nestling doves and, at least, adult ruddy ground-doves (Columbina talpacoti). Fruits are most abundant in the wet season. In the dry season, they eat fewerfruits and more invertebrates, along with alternatives such as roots. In the dry season, hard fruits of Guazuma tomentosa (Sterculiaceae) are important, and they forage more on the ground, taking Pomacea freshwater snails and tettigoniid grasshoppers in the leaf litter. A leaf flush occurs with the first heavy rains of the wet season, and phytophagous caterpillars become abundant prey at that time.
Breeding. Female Guianan Weeper Capuchins have a 16-20day reproductive cycle. Births occur throughout the year but peak in May-June. Eyebrow raising is absent from the proceptive female’s repertoire, but partners grin and gaze at each other and tilt their heads. There is also the dance of the female running around the male, touching him, and running away. A female producesa single offspring about every two years, after a gestation of 149-158 days. Infanticide has been reported, although males are generally tolerant of young and will often play with them. Female Guianan Weeper Capuchins are sexually mature at 4-7 years old, and males mature about a year after that (although full adult size is not reached until c.15 years old). Births are most common at the end of the dry season and early wet season. Infants are entirely dependent on adults until they are about four months old. At 4-12 months old, they gradually become more independent. They are considered juveniles at twelve months, although they continue nursing sporadically for another six months.
Activity patterns. Overall, Guianan Weeper Capuchins spend almost 70% of their day foraging (c.22% catching and eating animals, 17% eating plant material, the rest searching for, extracting, and processing food items). Traveling takes up ¢.22% oftheir day, and resting and social behavior take up the remaining 8%. Males tend to rest more, and females tend to engage more in social activities. In the last month of the dry season, they spend ¢.58% of their day foraging and 19% traveling, but in the first months of the rainy season, they spend 43% of the day foraging and 17% traveling. They play and socialize much less in the dry season (6%) than in the wet season (20%). In the Llanos, groups of Guianan Weeper Capuchins leave their sleeping sites often in the dark and always before sunrise, and move rapidly to feeding sites, especially fruiting trees. They forage throughout the day, but less around midday, particularly in the hot dry season. In the dry season, foraging declines after c.10:30 h and increases again after c.14:30 h and particularly in the late afternoon before retiring to their sleeping sites. Much of their foraging is done on the ground. Males spend more time lower in trees and foraging on the ground than females. Adult and subadult males spend as much as 34% of their day on the ground, whereas adult and subadult females limit their time on the ground to ¢.10%, spending more time in the trees at heights of 5-10 m.
Movements, Home range and Social organization. Group sizes of Guianan Weeper Capuchins average c¢.20 individuals but can be as large as 36 individuals, with the most skewed sex ratios of any of the capuchins (c.1 male:2 females). A group of ¢.20 Weeper Capuchins studied in the Llanos at Hato Masguaral in the late 1970s was composed of a single adult male, two subadult males, and 6-8 adult females, along with juveniles and infants. As a ripe-fruit specialist, their annual home range was large, up to 275 ha, and the group traveled 1046-3580 m/day, averaging 2141 m/day. When foraging for animal prey, a group is considerably spread out, over as much 150 m. Males disperse, sometimes as early as two years old but generally between three and six years old. Solitary males are rarely seen and only for a short period. Males may transfer between groups more than once. Low-ranking and old females may disperse, but they most often stay in their natal groups. Males and females have separate dominance hierarchies, with the alpha female ranking immediately below the alpha male. Home ranges of neighboring groups overlap, but groups generally avoid each other when their paths cross, except when in a fruiting tree. Larger groups displace smaller groups at fruiting trees, and this is seen as a crucial advantage at times of food shortage (dry season) and a reason why reproductive success of the females is higher in large groups than small groups. Females in large groups have a quite constant food intake during the year, but those in smaller groups have a high food intake in the wet season but very low intake when food is scarce in the dry season. Males also have better reproductive success in large groups because they have longer tenure and access to more females. With more subordinate and subadult males in a group, they are lesslikely to suffer aggressive takeovers by males from other groups, which not only ends (at least temporarily) the resident alpha male’s breeding career but also results in episodes of infanticide by incoming males, damaging the reproductive success of the females and the pastresident breeding male. Males remaining as subordinates in large groups have the advantage of a potentially rewarding tenure as dominant male, although his time as dominant will probably be shorter than it would be in a smaller group. An effect of group size on female fecundity has been shown at Hato Masaguaral and Hato Pinero. L. E. Miller, who studied Guianan Weeper Capuchins at Hato Pinero, argued that females in larger groups benefit from the group’s ability to commandeer the major fruiting trees in the dry season, and they also spend more time on the ground because of the higher overall vigilance, which is beneficial for their foraging rate when food is scarce. Females in smaller groups have less competition for food within the group but suffer more from a higher predation risk. They spend more time higher in the forest and much less time on the ground than females in larger groups, which is evidently detrimental to their feeding rate.
Status and Conservation. CITES Appendix II. Classified as Least Concern on The [UCN Red List. The Chestnut Weeper Capuchin has not been assessed independently. The Guianan Weeper Capuchin is hunted for meat in some areas and is generally less common than the sympatric Guianan Brown Capuchin. The Guianan Weeper Capuchin occurs in numerous large protected areas in the northern Amazon Basin.
Bibliography. Bodini (1989), Bodini & Pérez-Hernandez (1987), Boubli et al. (2012), De Ruiter (1986), Fernandes et al. (1995), Fragaszy (1986, 1990), Fragaszy, Fedigan & Visalberghi (2004), Fragaszy, Visalberghi et al. (2004), Freese & Oppenheimer (1981), Groves (2001), Hershkovitz (1949, 1955), Miller (1991, 1998a, 1998b, 2002a), Freese & Oppenheimer (1981), Mittermeier & van Roosmalen (1981), Oppenheimer & Oppenheimer (1973), von Pusch (1941), Robinson (1981, 1984a, 1986, 1988a, 1988b), Tate (1939), Valderrama et al. (1990).
description: Published as part of Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Cebidae, pp. 348-413 in Handbook of the Mammals of the World – Volume 3 Primates, Barcelona :Lynx Edicions on pages 409-410, DOI: 10.5281/zenodo.6628559