Sapajus macrocephalus
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
Sapajus
Sapajus macrocephalus

description: 15.
Large-headed Capuchin
Sapajus macrocephalus
French: Sapajou a grosse téte / German: GroRkopf-Kapuzineraffe / Spanish: Capuchino de cabeza grande
Taxonomy. Cebus macrocephalus Spix, 1823,
forests of Lago Cactua, near Rio Solimoes, Amazonas, Brazil.
In 2001, J. S. Silva, Jr. argued for just two species of Amazonian robust/ tufted capuchins: S. apella in the eastern and central Amazon Basin and S. macrocephalus (recognized as a subspecies of apella by W. C. O. Hill in 1960 and C. P. Groves in 2001) in the western Amazon (distributional limits poorly defined). Following Silva, S. macrocephalus includes, as junior synonyms, Simia fatuellus from the upper Magdalena Valley, Colombia (recognized by Hill and Groves), Cebus fatuellus peruanus from Huaynapata, Marcapata, 760 m, Cuzco, Peru (recognized by Hill, Groves, and R. Aquino and F. Encarnacion in 1994), Cebus apella maranonis from Hamburgo, Peru (recognized by Hill and Aquino and Encarnacion), Cebus pallidus from the Rio Beni (recognized by Hill, Groves, and S. Anderson in 1997), Cebus libidinosusjuruanus from opposite Joao Pessoa, Rio Jurud, Brazil (recognized by Hill and Groves), and Cebus apella magnus from the Rio Putumayo, 1° N, 76° W (recognized by Hill). The form in central and northern Bolivia (south of the Rio Madre de Dios) has also been referred to as S. libidinosus pallidus and S. apella pallidus in recent publications. Preliminary genetic studies in 2012 by J. W. Lynch Alfaro and her coworkers failed to indicate that apella and macrocephalus were distinct taxa, but further research is needed. Monotypic.
Distribution. Upper Amazon Basin in E Colombia (N as far as the Rio Arauca on the Venezuelan border; an isolated population in the upper Rio Magdalena in the Huila Department), E Ecuador, E Peru, W Brazil, and C & N Bolivia (S at least to the upper Rio Beni); the exact limits of its distribution have not been delineated, and particularly where they meet those of the Guianan Brown Capuchin (S. apella) in the Rio Madeira Basin, in the N along the Orinoco, and in the interfluvium of the Rio Solimoes and upper Rio Negro.
Descriptive notes. Head-body 37.5-45.5 cm (males) and 39.5-40.9 cm (females), tail 42-549 cm (males) and 41.6-42 cm (females); weight 2:9.4-6 kg (males) and 1.3-3.4 kg (females). The overall color of the Large-headed Capuchin is gray-brown or gray-ochery to dark brown above, with a dark dorsal stripe, and yellow-fawn or red-gold (occasionally blackish) below. Sides of the neck are lighter, upper arms are pale yellowish, and legs are black with yellow-fawn or red-gold below. In the darkest individuals, the crown contrasts very little with the body, and shape of the crown cap in front (i.e. angular or broad) and presence of white margins are variable. Adults have very welldeveloped, high, pointed crown tufts that resemble horns, which become reduced or flattened with age. There is often a gray-white stripe running from eye to ear. Three forms of the Large-headed Capuchin have been noted. The Colombian form is bright brown above and red below and has a prominent dorsal stripe. Its face is almost naked and a dark purplish flesh color. The Peruvian form is uniformly dark chestnut-brown above, becoming more reddish toward the flanks, and is deep yellow-brown below. A dark brown band runs down the midline of the back. Its legs, tail, and (occasionally) forearms are black. Its cap is black and distinct, and temples and sides of the crown are often white. There is a crescent-shaped whitish patch above each eye. Crown tufts are absent or minimal. The third form from Brazil is reddish-brown above with a very pronounced blackish dorsal stripe. The throat and upper chest are blackish or pale reddish-buff, and limbs and tail are dark brown or black.
Habitat. Evergreen humid tropical lowland forests, including seasonally inundated forests, bamboo forest, palm swamps, and subtropical montane (cloud) forests of the upper Amazon Basin, up to elevations of 1800 m in Peru and 1300 m in Colombia. In Ecuador, the Large-headed Capuchin is mostly found below 600 m, but there is an isolated population in the Rio Magdalena, Colombia, at 2700 m. It extends north through the deciduous gallery forests of the Eastern Llanos of the eastern tributaries of the Orinoco in Colombia as far north as Rio Arauca, but apparently not extending into Venezuela (Maracaibo Basin).
Food and Feeding. Diet of the Large-headed Capuchin largely consists of fruit and insects but also seeds, pith, leaves, stems, flowers, nectar, millipedes, spiders, snails, frogs, lizards, nestlings, and bird eggs. Fruits include succulent drupes and berries,especially of Moraceae, and palm (Arecaceae) fruits, which are a particularly important part of their diet. A study by K. Izawa and colleaguesin a site near the Rio Duda on the western border of Sierra de la Macarena National Natural Park in Colombia recorded six species of palmsin their diet, four of which— Astrocaryum chambira, Jessenia polycarpa, Socratea elegans, and Oenocarpus mapora—were systematically exploited for their fruits, particularly the albumen. Large-headed Capuchins also eat flowers and mesocarp of ripe fruits from Astrocaryum and Jessenia. They put young Astrocaryum fruit up to their mouth, raise their head up, and with one bite, open it and drink the albumen. With older Astrocaryum fruit, they bite off the exocarp and puncture the already woody husk through the germ-pore with their canine teeth, and then bash it against nodes of giant bamboo (Bambusa, Poaceae) and lick up the yogurt-like albumen that comes out. When olderstill, with the germ-pore closed, they eat the lipid-rich mesocarp and then open the fruit by bashing it against bamboo nodes until it cracks, and they then eat the hardened albumen. Studies by J. Terborgh and C. Janson in Manu National Park and Biosphere Reserve, Peru, showed that palms are also important to Large-headed Capuchins, including, to varying degrees, Astrocaryum, Bactris, Iriartea, Mauritia, and Scheelea. They eat immature inflorescences and pith of frond petioles (rachis) of Astrocaryum and Scheelea, fleshy lipid-rich mesocarp of fruits of all palm species, apical meristem (palm heart) of Bactris, and endosperm (albumen) of seeds of Astrocaryum. Astrocaryum and Scheelea plams are abundant in Manu, and with densities estimated at 39 trees/ha and 25 trees/ha, respectively, a group of Large-headed Capuchins with a home range of ¢.50 ha has access to more than 1000 trees of each species. Fruits comprise 99% of the plant part of the diet in the wet season, but only 66% in the dry season. Fruits and seeds (also pith and meristems) of these palm species are the mainstay (64% of feeding time) of the diet through the early dry season (May-July) when fruit is scarce. Figs are also important in the early dry season (27% of the diet) and even more so in the second one-half of the dry season (49% of the diet). In the wet season,fruits of palms or fig trees comprise 82% (October-December) to 90% (January-April) of the diet. C. Peres made a particular study of seed predation by Large-headed Capuchins at Urucu in the Purus Basin, south-western Amazonian Brazil. Seeds of palms such as Jessenia (= Oenocarpus) bataua are important in their diet throughout the year. Their asynchronous fruiting and relative abundance (22-7 trees/ha) meant that the impact of Large-headed Capuchins was not significant—many trees were never visited while fruiting. Seeds and arthropods were important foods in the middle of the dry season when fleshy fruits were rare, and at this time, Large-headed Capuchins had a devastating effect on seed crops of twelve Cariniana micrantha (Lecythidacae) that fruited during a 3-5 week period. The fruit of C. micrantha is a woody pyxidia containing numerous winged seeds that are dispersed by the wind when an operculum opens and releases them. Large-headed Capuchins pick off the fruits and bash them, at first with force and then more gently when they perceive that the operculum seal has cracked. If the operculum seal does not crack, they drop the fruit and try another. If it cracks, they pull it out and pick off and eat the highly nutritious seeds. Almost all of the fruits were either successfully cracked open and their seeds eaten (69:5%) or rotted on the forest floor (30-1%). In Colombia, Izawa also noted Large-headed Capuchins eating young bamboo leaves and occasionally leaf stems from Monstera pertusa (Araceae), Calathea (Marantaceae), and Heliconia (Heliconiaceae). Izawa observed an adult female catching and eating a Proboscis Bat (Rhynchonycteris naso). The insects eaten by Largeheaded Capuchins include ants (adults, larvae, pupae, and eggs) that they look for in bamboo internodes and Crematogaster and Azteca ants that they find in hollow twigs and small rotten branches. When foraging in bamboo, they scan culms, probably looking for signs of attack or small holes, and then run their hands up the internodes, tapping lightly and listening for frogs or insects (including orthtopterans) inside. If they hear movement, they bite and rip open the culm to take the prey. They also break open ant nests in the joints of the leaves of Phenakospermum guyanense (Strelitziaceae) and among the moribund leaves of Jessenia. Large-headed Capuchins bite open termite nests to eat adults, nymphs, and eggs; they hunt for grasshoppers among leaf litter and debris piles caught in the palm trees; and they eat beetle larvae, wasp larvae, and honeycombs whenever they find them. Terborgh noted that foraging for animal prey by Large-headed Capuchins is essentially manipulative and destructive, biting open and breaking bamboo canes, dead branches, and palm rachides; stripping bark; and generally rummaging in leaflitter and forest debris, particularly in palm crowns and liana tangles. Large-headed Capuchins spend more time searching in palms (32% of animal prey foraging time) than sympatric species of Cebus (21%), which are less destructive in their foraging and spend more time looking for insects hidden in more easily manipulated substrates (e.g. leaf curls and litter).
Breeding. The ovarian cycle of the Large-headed Capuchin is c¢.22 days. A female is proceptive, constantly soliciting the attention of and mating (once a day at most) with the alpha male during her ovulatory cycle of c.5-6 days. During the first 3-4 days of her ovulatory cycle, she persistently follows the alpha male, approaching, touching, running away, grimacing, eyebrow-raising, making distinctive calls, and adopting submissive postures. On the penultimate day of her ovulatory cycle, the female begins to solicit other males, and the alpha male follows her and prevents them from approaching, although aggression between males is infrequent. Active solicitation by the female is believed to be related to the alpha male’s ability to control the other group members’ access to food sources, particularly palm fruits, during periods of food scarcity. The alpha male tolerates females with whom he has mated. He may also intervene on a female’s behalf in disputes over food with other group members, particularly subordinate males. Food shortage at Cocha Cashu in Manu National Park and Biosphere Reserve during the early dry season is considered to be critical enough to affect the females’ health and fecundity. It is unclear why females solicit and copulate with other males at the end of their ovulatory cycle, but it may ensure pregnancy if the alpha male is infertile and confer future benefits considering that an alpha male’s tenure may be limited. Gestation is c.153 days. At Sierra de la Macarena National Natural Park, Colombia, most births occur in the early wet season (February—June). Females first give birth at 7-8 years old. Interbirth intervals average 25-6 months when the infant survives but 15-5 months when the infant is lost. At Cocha Cashu, births occur in the early and middle part of the wet season (October-December) when fruit abundance is increasing. Infants begin to leave their mothers at about three months old, and juveniles carry infants. Sixmonth-old infants eat tidbits of food, and weaning begins at 8-12 months and is completed by ¢.20 months. Males, but not adult females, play with the infant.
Activity patterns. Large-headed Capuchins in Manu National Park and Biosphere Reserve spent 50% oftheir time foraging for small animal prey, 22% traveling, 16% feeding on plant material, 12% resting, and the remainderin social activities (e.g. grooming, courting, and playing). Eating fruit peaks in the early morning and again in the middle of the afternoon, but the predominant activity during the day is foraging for animal prey. Resting peaks for 30-60 minutes at ¢.12:00 h.
Movements, Home range and Social organization. At Manu National Park and Biosphere Reserve, groups of Large-headed Capuchins are generally 8-14 individuals, with one alpha male, one or more subordinate males, and 1-4 adult females. At Sierra de la Macarena National Natural Park, five groups monitored during five years ranged in size as follows: 13-16, 14-19, 8-10, 12-13, and 17-23. The last group had 7-8 adult males and 4-5 adult females. At one point when there were seven adult males in this group, five of them fought, causing serious wounding and the death of one of them. The group split into two groups, based on two dominant female lineages: one with six individuals and the other with eight individuals. The larger of the new groups grew over the following two years to 15 individuals, with three adult males and five adult females. Home ranges of groups at Manu are ¢.80 ha, with daily movements of 1630-2620 m. Male and female Large-headed Capuchins form hierarchies. Dominant individuals are rarely challenged by subordinates. There is a single alpha male, and the most dominant female is immediately below him in rank. Disputes are typically over food sources, particularly palm fruits, figs, Strychnos (Loganiceae) fruits, and Combretum (Combretaceae) nectar. Dominant individuals feed more at these food sources than subordinates, and the alpha male is able to commandeer feeding sites and allow females that mate with him to feed, while disallowing others. He favors his presumed offspring the same way. Individuals that he is intolerant of spend more time foraging for animal prey to compensate their otherwise reduced food intake. This is believed to be related to the evolution of their unusual mating system of prolonged proceptive behavior by females toward the alpha male during the periovulatory periods. Cebus males, by contrast, monitor females reproductive status, are aggressive to them, and pursue them to mate with them rather than vice versa. Males are more vigilant for predators (especially raptors) than females, and they confront and mob terrestrial predators and intervene when individuals in the group are threatened.
Status and Conservation. CITES Appendix II. Classified as Least Concern on The [UCN Red List (as Cebus macrocephalus). Large-headed Capuchins are hunted, and they can become a principal target when larger spider and woolly monkeys are locally extirpated. There are areas where they have been extirpated in Ecuador and Peru. They are now classified as Near Threatened in Ecuador, but they are adaptable and wide ranging and occur in large, remote protected areas in the western Amazon Basin.
Bibliography. Aquino & Encarnacion (1994b), Defler (1982, 2003b, 2004), Escobar-Paramo (1989), Fragaszy, Fedigan & Visalberghi (2004), Fragaszy, Visalberghi et al. (2004), Freese & Oppenheimer (1981), Groves (2001), Hernadndez-Camacho & Cooper (1976), Hill (1960), Izawa (1978b, 1979a, 1992, 1994a, 1994b), Izawa & Mizuno (1977), Janson (1984, 1985, 1986), Lynch Alfaro, Boubli et al. (2012), Peres (1991c¢), Phillips, Bernstein et al. (1994), Phillips, Grafton & Haas (2003), Podolsky (1990), Rylands et al. (2005), Silva (2001), Struhsaker & Leland (1977), Terborgh (1983), Torres (1988), Wright & Bush (1977).
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 403-404, DOI: 10.5281/zenodo.6628559