SOCIAL ORGANIZATION AND BEHAVIOR
Stump-tailed macaques live in large, multi-male/multi-female
groups of five to 60 individuals (Fooden 1990; Rowe 1996; Srivastava 1999).
Females remain in their natal groups
while males leave before sexual maturity and immigrate into a new group to breed
(Fooden 1990). Stump-tailed macaques exhibit
female philopatry, and
matrilineal hierarchies are enforced by
both contact (slapping, hitting, and biting) and non-contact (threatening displays)
aggression. Aggressive behavior between female stump-tailed macaques is not as
physically dangerous as it is for other macaque species, which are more tyrannical
(Butovskaya 1993). Adult males, after immigrating into a new group, also form a
strict dominance hierarchy through fighting, but
are characterized as egalitarian because they are quick to reconcile comapred to other macaque species.
After a fight, stump-tailed macaques have ritualized reconciliation behaviors:
the subordinate presents his rump to the dominant individual that acknowledges
the gesture. The dominant male may embrace and kiss the subordinate, which will
respond with "teeth chattering" and "lip smacking," both signs of submission.
Finally, the subordinate offers a hand to the dominant individual who will softly
mouth or "mock bite" the hand. After this interaction, the bond is purportedly
restored and the dominance hierarchy is reinforced (de Waal 1993; Srivastava 1999).
Males are dominant over females, and the alpha male guides the groups travel and
he and several males who rank directly below him in the hierarchy guard against
predators while the group forages
(Fooden et al. 1985; Srivastava 1999). Adult males protect infants and juveniles
if they are in potential danger and interfere in female-female interactions (Srivastava 1999).
The behavior of stump-tailed macaques based on whether they live in captive or
semi-free ranging colonies or in wild groups. They have been described as tractable and
egalitarian in captivity but they have been reported to attack and kill
humans in the wild, if provoked (Fooden 1990).
REPRODUCTION
Stump-tailed macaques have low reproductive rates compared to other macaque species.
Females reach sexual maturity around four years of age and have an
ovarian cycle lasting 30 days. Most mating occurs in October and November in the wild, during
February and March in Mexico, and is not seasonal in captivity (Brereton 1994).
Females begin to produce offspring between 4.5 and five years of age and will
reproduce until about 17 years of age (Fooden 1990). Males reach sexual maturity
around four years of age as well, but do not reach adult size until around six years.
Frequency of mating correlates with dominance rank among stump-tailed macaques.
The highest-ranking males monopolize receptive females while the highest-ranking
females are also the most likely to do the most mating (Brereton 1994).
Lower-ranking male stump-tailed macaques use alternative methods to gain mating
opportunities. One way they do this is by lagging behind with a reproductively
active female as the group travels. When the dominant males are out of sight,
the lower-ranking male mates with the female and the couple then moves to rejoin
the group (Brereton 1992). Both males and females solicit mating, females by
presenting their rumps to males and maintaining eye contact over one of their
shoulders, and males by approaching a female, sitting next to her, and giving a
"teeth chattering with grimace" display (Brereton 1994). During
copulation, other members of the group
harass the pair (Srivastava 1999). Gestation
lasts 177 days and females give birth about every two years in the wild
(Fooden 1990; Srivastava 1999).
PARENTAL CARE
Macaque mothers are the primary caregivers for their offspring, though all
of the females in the group direct attention to infants and will
approach, play with, carry, groom and protect them, especially if they
are born to a high-ranking mother. By protecting a high-ranking female's
infant, a lower-ranking female may expect rewards of tolerance and reduced
aggression by the high-ranking female (Estrada & Estrada 1984).
High-ranking adult males also direct some attention towards and give protection to
infants within the group. This may be because higher-ranking males have
more chances to mate with females and because there is increased likelihood
that infants in the group are their offspring, males have some interest in
protecting them from danger (Bauers & Hearn 1994). Stump-tailed macaques are
considered permissive mothers compared to other species, and early on they
allow the infant to independently explore the surrounding environment
(Maestripieri 1995). They may be this lenient because other group members
are interested in infants but never treat them roughly or "kidnap" them as
is seen in other macaques (e.g., M. nemestrina
and M. fascicularis)
(Bauers & Hearn 1994). Stump-tailed macaque infants are dependent for the
first nine months of life, after which they are weaned,
and become increasingly independence until adolescence, at 18 months (Srivastava 1999).
COMMUNICATION
Communication between stump-tailed macaques largely takes the form of vocal or gestural signals.
Frequently seen gestures or postures are used to reinforce the
dominance hierarchy and reconcile after aggressive interactions. "Hindquarter presentation"
is the most common gesture seen among stump-tailed macaques and is displayed by subordinates to
appease dominants. Other submissive signals include "bared-teeth," "lip-smack," "teeth-chatter,"
and "present-arm," in which one arm is put directly in front of the face of the dominant
individual to be bitten (Maestripieri 1996).
Vocal communication is also important among stump-tailed macaques. The most common vocalization
is the "coo" heard in a variety of contexts, but especially relevant as group members maintain
contact with each other while foraging and when approaching one another to initiate friendly
interactions such as grooming or huddling (Rowe 1996). "Basic grunts" are another ubiquitous
signal among stump-tailed macaques; they are commonly heard between animals who are greeting one
another, after aggressive interactions and when one animal is interested in another (Bauers 1989).
Alpha males use a "roar" when displaying against predators
or threats. Infants use "trilled-whistles" as a signal of distress to their mothers when they
are out of visual contact with them or if they need to be retrieved because they cannot descend
a structure that they have climbed (Bauers 1989; Maestripieri 1995).
Content last modified: October 4, 2005
Written by Kristina Cawthon Lang. Reviewed by Hideo Uno.
Cite this page as:
Cawthon Lang KA. 2005 October 4. Primate Factsheets: Stump-tailed macaque (Macaca arctoides) Behavior. <http://pin.primate.wisc.edu/factsheets/entry/stump-tailed_macaque/behav>. Accessed 2008 May 13.
