White-Faced (-Throated, -Headed) Capuchin
White-Faced_Capuchin_Mike_Wilson_2.JPG
White-faced capuchin in Costa Rica
Cebus capucinus
Classification:
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Cebidae
Genus: Cebus
Species: C. capucinus


Range/Abundance:
White-faced capuchins are native to Central America, specifically Honduras, Nicaragua, Costa Rica, and Panama and areas of South America, specifically Argentina, Brazil, and the coasts of Columbia and
map.jpg
Geographic Distribution
Ecuador.1,2 The abundance of these primates varies depending upon location. While white-faced capuchins are not currently in danger of extinction, deforestation threatens to reduce the availability of adequate habitats and food sources.
1

Coloration and Morphology:

Coloration:
White-faced capuchin monkeys exhibit unique and identifiable coloration. A white-faced capuchin possesses a black or dark brown dorsum, hindquarters and head cap, a white or cream upper chest, forearms, and facial fur, and tan or pink facial skin.1 The unique coloration of these primates has earned them their common name, “mono cara blanca” (white-faced monkey).4 Furthermore, the black section of hair on the heads of white-faced capuchins rese
White-Faced_Capuchin_2.jpg
Prehensile Tail, White-faced capuchin in Costa Rica
mbles the hoods worn by Capuchin monks (an Italian order founded in the 1500's), hence the name of these primates.
18

Dimorphic Size/ Growth:

The sizes of white-faced capuchins are dimorphic, in that males are approximately 1.4 times the weight of females. Adult males weigh an average of about 3.8 kg while adult females weigh an average of about 2.7 kg.5 White-faced capuchins are approximately 435 mm (17.13 in) in length.1 Juvenile white-faced capuchin males are classified as sub-adults at eight years of age when they begin to experience distinct physical and social changes. Sub-adult males begin to interact with females more frequently and spend less time engaging in playful activity. Also, the males begin to undergo physical transformations as they transition from a tall and thin figure to a huskier frame and finally achieve full adult size at ten years of age.6 Female juvenile white-faced capuchins achieve sexual maturity between four and seven years of age.1
White-Faced_Capuchin_Mike_Wilson_3.JPG
White-Faced Capuchin in Costa Rica


Morphology:
Capuchin monkeys also possess fairly short, fully-haired prehensile tails. Observations at La Suerte Biological Research Station confirm the use of prehensile tails during feeding and foraging in order to provide support when searching within and under substrates for food. The prehensile tail is rarely used during daily movement and locomotion as white-faced capuchins generally travel via walking, leaping, or climbing.7 Finally, compared to any other primate besides humans, white-faced capuchins possess the greatest brain-to-body size ratio.18

White-Faced_Capuchin_3.jpg
Habitat of the white-faced capuchin in Costa Rica
Habitat:

While these highly adaptable primates can be found in wet, dry, primary and secondary forests, they generally prefer tropical evergreen forests and dry deciduous forests. White-faced capuchins have been observed in high altitude cloud forests as well as wet lowlands, but they usually live at elevations of about 1100 meters.
1 These primates spend the majority of their time within the treetops with home ranges varying between 50 to 85 hectares.3 White-faced capuchins perform urine-washing, or the process of immersing their hands and feet in urine. This behavior may serve to designate and establish control over a particular territory by leaving behind an identifiable scent.2 While the exact function of urine washing is unknown, white-faced capuchins are territorial primates.

Behavior:


Assemblages:

White-faced capuchins are social primates and live in groups of three to thirty members, with an average size of approximately fifteen individuals. These groups include males, females, and juveniles with approximately 4.4 adult males and 5.4 adult females per group.6 Living within a group provides certain benefits, primarily protection from competitive and aggressive extra-group white-faced capuchins or from predators. Studies of group dynamics within white-faced capuchins at Santa Rosa National Park in Costa Rica reveal the importance of vigilance, or alertness towards potential threats. T
White-Faced_Capuchin_8.jpg
Family of white-faced capuchins, Photo credit http://tamarindodailyphoto.blogspot.com/2009/01/white-faced-capuchin-monkey-family.html
he greater vigilance among males rather than females indicates that vigilance is geared towards males from other groups of white-faced capuchins in an effort to protect against potential breeding threats. This hypothesis is supported by the shorter amount of time spent by males foraging in comparison to females. Males tend to regulate external threats, while females are concerned with internal social relationships.
8 Furthermore, at Santa Rosa National Park, Costa Rica, a group of white-faced capuchins came to the defense of one of their group members when a capuchin was captured by a Boa constrictor. The male group members remained at the scene of the attack for the longest period of time.9 Members of the group will separate during foraging and traveling, but remain relatively cohesive during resting and social interactions. Vocal communication serves to maintain contact among members of a group. Females are “philopatric” and remain within their natal group while males will leave their birth group.10 Males undergo a natal emigration at the average age of 4.5 years and leave their natal group often in parallel with other familiar males.6

Hierarchy/ Social Structure:

Within each group, a hierarchy exists among males and females. The alpha male is the dominant individual within the group, and a ranking exists among the subordinate males. Adult males are typically superior to adult females; however, the alp
White-Faced_Capuchin_9.jpg
Photo credit http://www.ric.edu/faculty/mbaker/index.html
ha female generally trumps some of the males at the bottom of the hierarchy.
11 Politics and alliances certainly play a role in maintaining group dynamics. A significant degree of competition and aggression exists between intra-group males, and a balance between protecting the group from outsiders and foreign mating rivals versus competing internally within the group for resources and dominance must be ensured. For example, if a male member of the group goes missing, the remaining male group members exert considerable effort towards attempting to find the missing male, including the bellowing of a distinct "lost call." Furthermore, if one male is experiencing antagonism from a male within a competing group, then the other male group members will come together in defense of their comrade. Takeovers are fairly common and can result in the death of group members, indicating the importance of a degree of cooperation among males.10

Alpha Male:
Certain characteristics distinguish the alpha male from the subordinate males within a group. The alpha male, who occupies a central spatial position within the group, typically engages in more aggressive behavior towards subordinate males, but receives less aggression in reciprocation. The alpha male also engages in certain actions with greater frequency, specifically behaviors such as urine rubbing, piloerection (elevation of the hair), branch-breaking and branch-shaking. Furthermore, the alpha male tends to disrupt the formation of any strong bonds between subordinate males with one another in order to ensure that a potentially dangerous alliance does not form. However, coalitions do sometimes form within a group against other males within the same group. These coalitions may also be directed against white-capuchin males from other groups, against predators, against other non-threatening animals, and rarely agains
White-Faced_Capuchin_10.jpg
Photo credit http://www.panama-guide.com/index.php?topic=animals&page=2
t juveniles. These non-capuchin predators include humans, howling monkeys, rattlesnakes, boa constrictors, dogs, birds, stinging insects, and coatis. Furthermore, sometimes coalitions are formed against imaginary predators, perhaps in order to strengthen male relationships. The alpha male also typically engages in stronger relationships with the females within the group. Strong female-male partnerships, characterized by frequent grooming and close proximity, are important forces within group politics. Female support for the alpha male may be necessary in order to maintain control and dominance. The alpha male must devote considerable energy towards maintaining strong alliances with philopatric female members of the group, especially high-ranking females.
10 Furthermore, alpha males are often provided more mating opportunities with females in the group. Females also benefit from strong relationships with high-ranking males in the group. Female white-faced capuchins are especially concerned about the safety of their young. Females are the care-takers for infant capuchin monkeys.1 Studies at Lomas Barbudal Biological Reserve in Costa Rica suggest that females often exhibit fearful behavior towards neutral males and will sometimes attack harmless bystanders in order to detract attention away from themselves. Male-female coalitions within groups are common and serve to provide the female with protection from potentially infanticidal extragroup white-faced capuchins at the cost of increasing food theft from their male coalition partner.5

Social Games/ A Culture of Their Own?:
Researchers have gathered significant observations of various
hand_sniffing.jpg
Hand sniffing, Photo credit http://www.jstor.org/pss/4015178
social games among white-faced capuchins. The games are classified as social traditions, in that these behaviors are
finger-in-mouth.jpg
Finger-in-mouth game, Photo credit http://www.jstor.org/pss/4015178
learned and often passed on to other members within a group. These behaviors are believed to serve as social mechanisms in order to test the bond and relationship between two white-faced capuchins. Some of these traditions include:
1. Hair-in-mouth game: One monkey bites a clump of hair off another’s face and the two use their teeth to pass the clump of hair until all of it has fallen.
2. Fingers-in-nose game (hand sniffing): Two monkeys sit with their fingers up each other’s noses.
3. Finger-in-mouth game: While one monkey grips another’s fingers in his mouth, the other must try to retrieve his hand back from the captor.
4. Sucking of another’s body parts: Fingers, tails, ears
5. Passing objects with teeth: pebbles, sticks
18

Ecology:

Prey, Diet:
The diet of diurnal (active during the daytime) white-faced capuchins consists primarily of fruits and nuts. However, insects, other invertebrates, and small vertebrates (squirrels, tree rats, lizards, and birds) are
White-Faced_Capuchin_7.jpg
Photo credit http://fireflyforest.net/firefly/2007/10/10/white-faced-capuchin-monkeys/
also consumed if available within the habitat. White-faced capuchins are opportunistic in response to food availability and will consume a variety of plants and animals. While their diet differs depending upon the
White-Faced_Capuchin_4.jpg
Two white-faced capuchins feeding on fruit in Costa Rica
season and the region, white-faced capuchins generally consume a diet which consists of 50-80% fruit, 20-30% animal matter, and 10% plants.
1 Studies conducted at Santa Rosa National Park in Costa Rica suggest higher levels of vertebrate predation than traditionally presumed, including such prey as lizards, adult parrots, magpie jays, bird eggs, squirrels, bats, and coatis. It has been suggested that high levels of vertebrate predation may be favored if an abundance of suitable prey is available and if competing carnivores are lacking. Furthermore, Linda Fedigan from the University of Alberta hypothesizes that vertebrate predation may be favored when the energy yield per time spent foraging for vertebrates is greater than for other food sources. Observations suggest that male white-faced capuchins exhibit greater vertebrate predation because of their larger body size and male dominance.12

Foraging/ Food Processing Techniques:
A variety of foraging techniques have been observed among white-faced capuchins regarding their attainment of food sources and the subsequent preparing of the food. White-faced capuchins are extractive foragers and search for food within and under trees, rotting wood, branches, termite nests, the bases of palm fronds, bromeliads, epiphytes and bark.13 Panger et al. observed a multitude of foraging strategies within three similar ecological sites in Costa Rica. For example, common foraging mechanisms include pounding and rubbing of food against a substrate. These techniques are utilized in order to break open hard fruits and isolate particular plant components. Furthermore, these techniques may serve to
eliminate hair from particular prey, to remove harmful substances from food such as biting insects, or to remove fruit from a bunch. Tapping is also a common foraging mechanism, used especially to check for fruit ripeness. Less commonly observed strategies include army ant following, in which the monkeys follow army ants and catch the insects and small vertebrates that disperse as a result of the crowd of moving ants. Leaf wrapping among white-faced capuchins has also been observed, in which food is wrapped within a leaf and rubbed against a substrate. This mechanism serves to avoid touching a prey’s dangerous chemical or mechanical defenses. Finally, some monkeys use substrates as fulcrums in order to break into a fruit or shell.
14 Furthermore, regarding vertebrate prey, white-faced capuchins often search and remove coati pups and young squirrels from nests. They also search parrot nesting holes and may even remove magpie jays from the sky or a nearby branch. Additionally, relay chasing is common, especially when pursuing squirrels or lizards, in which one or several capuchin monkeys chase after the prey. Scientists have observed white-faced capuchins surrounding squirrels in trees in order to eliminate the potential for escape, and subsequently forcing the squirrel to fall to the ground.12
Lastly, observers have noted food-associated calls among white-faced capuchins in Guanacaste Province, Costa Rica. Julie Gros-Louis suggests that these food calls do not serve to attract other conspecifics to the food source, but rather serve as a call of ownership or possession in order to avoid aggressive and competitive behavior from other capuchin monkeys. These calls ensure adequate distances between individual foraging white-faced capuchins.15

Predators/Response to Predators:
Predators of the white-faced capuchin include aerial, arboreal, and terrestrial species. Some of the more common predators comprise snakes, specifically tree boas (Corallus), and lanceheads (Bothrops).
Furthermore terrestrial members of the Felidae and Canidae families, such as jaguars (Panthera onca) and ocelots (Leopardus pardalis) represent fairly common predators. Reptiles like caimans (Caimans), aerial birds and raptors like harpy eagles (Harpia harpyja), humans, and other unfamiliar monkeys and conspecifics all comprise potential predators.
1

In response to predators, white-faced capuchins evoke alarm calls which serve to signal other members of the species of a potential danger and stimulate defense reactions. Acoustic studies and observations conducted by Fichtel, Perry, and Gros-Louis at Lomas Barbudal Biological Reserve in Guanacaste Province in northwestern Costa Rica distinguish between two general categories of alarm calls within which contain additional subcategories. These different alarm calls can be distinguished and differentiated by white-faced capuchin monkeys, resultin
White-Faced_Capuchin_6.jpg
Photo credit http://fireflyforest.net/firefly/2007/10/10/white-faced-capuchin-monkeys/
g in diverse responses. The first general category of alarm calls is evoked in response towards aerial predators, humans, and other capuchin monkeys. The second general category of alarm calls is directed towards terrestrial predators, snakes, caiman, and during severe aggressive interactions with other capuchin monkeys. The evolution of two distinct general alarm calls may be a result of different levels of urgency. The first group of predators requires more specific and urgent responses, thereby necessitating a distinction between alarm calls. Alternatively, the two general categories may serve to distinguish the direction of the predator. The first category of alarm calls is generally directed towards aerial predators while the second category of alarm calls is directed towards more terrestrial species. Fichtel et al. further propose the existence of distinct subtypes within each broad general category which may signal the precise type of predator and thereby evoke a specific defense response. White-faced capuchins may be capable of recognizing and differentiating between these subtypes.
16

Regarding the specific physical responses accompanying the detection of
a predator or the recognition of an alarm call, white-faced capuchins respond differently to the various aerial, arboreal, and terrestrial predators. In response to snakes and terrestrial animals, the monkeys mob together and engage in aggressive displays such as branch shaking and joint alarm calling. In response to aerial predators, like raptors, capuchin monkeys hide behind branches and descend lower towards the ground. Conversely, the monkeys travel upwards in response to human predators. White-faced capuchins may flee or run towards other unfamiliar capuchin monkeys. Response towards unfamiliar white-faced capuchin monkeys may be dimorphic.
16

Role as Seed Dispersers:
White-faced capuchins serve important roles as seed dispersers, thereby influencing the structure of forests, the dynamics of forest regeneration, and the preservation of plant populations. Experiments conducted by Wehncke, Valdez, and Domínguez at Palo Verde National Park, Costa Rica compare the quality and quantity of Acacia collinsii seed dispersal by white-faced capuchins versus the black howler monkeys, Allouatta palliate. White-faced capuchins generally feed in groups of 10-15 members, while subordinate members are forced to feed in trees with smaller crops, a contrast to black howler monkeys which feed in trees with a crop size suitable for the entire troop. Consequently, white-faced capuchins feed on more numerous plant species and spend only a limited amount of time in each tree. They travel further distances as well and have relatively short gut retention times. These factors result in the dispersal of seeds at greater distances from a parent plant, and a greater rate of defecation per day. Troops of black howler monkeys generally spend a greater amount of time resting within parent trees and all the individuals of the group tend to defecate at the same time, often under their sleeping locations. Wehncke, Valdez, and Domínguez hypothesize that the smaller and more spread out defecations produced by white-faced capuchins decreases the probability that rodents will remove and destroy the seeds from the feces. The larger defecations produced by groups of black howler monkeys provide greater odor and visual attractants to rodents.17 Therefore, white-faced capuchins serve as excellent and perhaps superior dispersers of plant seeds.

Indirect Interactions of Other Species with White-Faced Capuchins:
While foraging through the treetops, especially in their relay chases after vertebrates or in an effort to capture insects, white-faced capuchins charge through vines and leaves and tear apart bark and wood,
Slaty_Tailed_Trogan.JPG
Slaty-tailed Trogon in Costa Rica
causing several large insects to fall to the ground. Furthermore, white-faced capuchins are active during a much higher percentage of the day in comparison to other primates, as only approximately 14% of their days are spent resting. Studies at Barrow Colorado Island in Panama have noted an association between foraging white-faced capuchins and double-toothed kites. These small forest hawks travel below foraging capuchins and capture the falling insects resulting from the capuchin’s disturbances. Other scientists have observed a similar association between white-faced capuchins and Slaty-tailed Trogons (Trogon Massena) in Panama.
3

Experiences During Trip to Costa Rica:
Although we did not observe the white-faced capuchins during our 2010 trip to Costa Rica, the white-faced capuchins have been observed among the trees of La Selva and in the National Park of Cahuita. White-faced capuchins have been seen near the shore in Cahuita waiting for food from tourists and visitors.


References:

1. Long, J. and K. Francl. “Cebus capucinus.” [Online], Animal Diversity Web. Accessed March 6, 2010. <http://animaldiversity.ummz.umich.edu/site/accounts/information/Cebus_capucinus.html#0724d3b707ccf3c33463876c6eca7793>.
2. “Capuchin Monkey (Cebus capucinus)." [Online], Rainforest Alliance. Accessed March 6, 2010. <http://www.rainforest-alliance.org/resources.cfm?id=capuchin_monkey>.
3. Fontaine, Roy. “Observations on the Foraging Association of Double-Toothed Kites and White-Faced Capuchin Monkeys.” The Auk 97.1 (1980) : 94 – 98.
4. “Capuchin (White-Faced) Monkey.” [Online], Accessed March 6, 2010. <
http://www.costarica.com/things-to-do/land-activities/capuchin-(white%11faced)-monkey/>.
5. Perry, Susan. “Male-female social relationships in wild white-faced capuchins (Cebus capuchins).” Behaviour 134.7/8 (1997) : 477 – 510.
6. Jack, Katharine M. and Linda Fedigan. “Male dispersal patterns in white-faced capuchins, Cebus capucinus: Part 1: patterns and causes of natal emigration.” Animal Behaviour 67.4 (2004) : 761 – 769.
7. Garber, P.A. and J.A. Rehg. “The ecological role of the prehensile tail in white-faced capuchins (Cebus capucinus).” American Journal of Physical Anthropology 110.3 (1999) : 325 – 339.
8. Rose, Lisa M. and Linda Marie Fedigan. “Vigilance in white-faced capuchins, Cebus capucinus, in Costa Rica.” Animal Behaviour 49.1 (1995) : 63 – 70.
9. Chapman, Colin A. “Boa constrictor predation and group response in white-faced Cebus monkeys.” Biotropica 18.2 (1986) : 171 - 172.
10. Perry, Susan. “Male-male social relationships in wild white-faced capuchins, Cebus capucinus.” Behaviour 135.2 (1998) : 139 – 172.
11. Hall, Carolyn L. and Linda M. Fedigan. “Spatial benefits afforded by high rank in white-faced capuchins.” Animal Behaviour 53.5 (1997) : 1069 – 1082.
12. Fedigan, Linda Marie. “Vertebrate predation in Cebus capucinus: meat eating in a neotropical monkey.” Folia Primatologica 54.3-4 (1990) : 196 – 205.
13. Garber, P.A. and Paciulli, L.M. “Experimental field study of spatial memory and learning in wild capuchin monkeys (Cebus capucinus).” Folia Primatologica 68.3-5 (1997) : 236 – 253.
14. Panger, Melissa A. et al. “Cross-site differences in foraging behavior of white-faced capuchins (Cebus capucinus).” American Journal of Physical Anthropology 119 (2002) : 52-66.
15. Gros-Louis, Julie. “The function of food-associated calls in white-faced capuchin monkeys, Cebus capucinus, from the perspective of the signaller.” Animal Behaviour 67.3 (2004) : 431 - 440.
16. Fichtel, Claudia, Susan Perry and Julie Gros-Louis. “Alarm calls of white-faced capuchin monkeys: an acoustic analysis.” Animal Behavior 70 (2005) : 165 – 176.
17. Wehncke, Elisabet V., Catherine Numa Valdez and César A. Domínguez. “Seed dispersal and defecation patterns of Cebus capucinus and Alouatta palliate: consequences for seed dispersal effectiveness.” Journal of Tropical Ecology 20.5 (2004) : 535 – 543.
18. McDonagh, Sorcha. "Monkey Busi​ness." Science News 165.14 (2004) : 218 - 220.