Social enhancement for caged macaques: 36-44

Newly introduced partnersand pair compatibility (photos 36-44)



Photos 36* & 37: Once two potential partners have established their dominance-subordination relationship during the familiarization period (photo 36), they can be introduced in a different double cage [to avoid potential territorial antagonism: Reinhardt et al. 1987; Niemeyer et al., 1998] where everything is strange except the familiar partner (photo 37: Donna and Cathy hugging each other shortly after introduction).

  Photo 38*: Peter and Moon engage in allogrooming shortly after pair formation [Reinhardt, 1989a].
They have no reason to fight because they were given the opportunity to establish their dominance-subordination relationship in a harmless manner prior to introduction.

In a study with 154 females and 40 males, pair formation after pre-establishment of rank relations was accompanied by fighting in 'only' 2 (2.6%) of the 77 female pairs and in none (0%) of the 20 male pairs [Reinhardt, 1994a].




Photos 39* & 40*: This pair formation technique has been applied with similar success in stump-tailed (Macaca arctoides; photo 39, Reinhardt, 1994b), long-tailed (M. fascicularis; Asvestas, 1989; Lynch, 1998; photo 40 by Richard Lynch) and pig-tailed macaques (M. nemestrina; Byrum & St. Claire, 1998).

  How do you know that two partners are compatible?

(1) There is no serious wounding,
(2) none of them monopolizes food,
(3) none of them shows signs of depression,
(4) the dominance-subordination relationship between the two is unequivocal.
(5) Affiliative interactions are not reliable indicators that two animals are compatible.

Photo 41*: Two rhesus males who were reared in partial social isolation; they show their compatibility by sharing two apples [Reinhardt, 1990a].

  Photo 42: In a study with 77 female and 20 male pairs, partners were compatible throughout a one-year follow-up period in 88% of the female pairs and in 80% of the male pairs [Reinhardt, 1994a].

Overall, 'only' 11% (13/97) of the 97 monkey pairs were incompatible.
This figure is amazingly low when considering the fact the divorce rate in humans is about 50%. Obviously, monkeys possess certain social skills which most humans are lacking. Of the 194 animals tested, a total of 3 (1.5%) incurred serious, but not life-threatening injuries in the course of the one-year study period [Reinhardt, 1994a].




Photos 43 & 44: Pair compatibility has been ascertained in many cases over long periods of time [Reinhardt, 1994a,c]. Here, the two males Moon and Peter of photo 38 sharing favored food treats six years after pair formation. Male pairs are kept in male-only areas to avoid possible sexual competition triggered by the presence of females in the same room [cf. Coe, 1991].

  Cage design for pair-housed macaques (photos 45-49)

  Table of Contents