This study assessed the extent to which emotional reactivity to the social environment influences maternal behaviour in macaques. Visual monitoring and scratching were used as behavioral indicators of maternal and social anxiety in small captive groups of rhesus macaques. Maternal visual monitoring of the infant and of other individuals proved better predictors of individual differences in maternal protectiveness than did characteristics of the mother-infant dyad such as maternal age, experience and dominance rank, number of immature offspring present in the group, or sex of the infant. Unlike visual monitoring, maternal scratching was not linearly related to protectiveness. Mothers displaying low or high rates of scratching ranked low on protectiveness, and the most protective mothers were those who displayed intermediate levels of scratching. Although individual differences in maternal and social anxiety seem to be mediated by maternal age and experience, they might also be influenced by genetics and early experience.