Maguire-Herring, V., Stonemetz, K. M., Lynch, L. J. et al. 2013. The effect of weight on the compatibility of isosexual pairs of captive rhesus macaques (Macaca mulatta). American Journal of Primatology 75(S1), 77. (36th Meeting of the American Society of Primatologists Scientific Program, Abstract #148)

Recently, there has been an increase in the implementation of social housing as an effective behavioral management strategy to improve the psychological well-being of captive nonhuman primates. Social housing nonhuman primates with conspecifics provides many benefits such as increased affiliative behaviors, decreased abnormal behaviors, and ameliorating stressful situations. However, factors involved in determining compatible isosexual pairs are lacking. An examination of data collected on a total of 183 social introductions, (113 male and 70 female pairs) we found weight to be a factor in the outcome of the pairing. Of the 183 introductions, 129 were successful, while 52 were incompatible introductions. Isosexual pairs that were similar in weight (M= 0.7, SEM=0.1) were significantly more compatible than pairs that had weight discrepancies (M= 1.2, SEM=0.2), t (177)= 3.61, p<.001. Further analysis revealed that similar weights were a greater factor for successful male pairings than for female pairings. These data provides evidence that weight is an important factor in determining the compatibility of potential pairs and further illustrates the importance in understanding the factors involved when trying to implement a successful social housing paradigm.