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Examined were 5 years of data on the reproduction of a semifree-ranging population of Barbary macaques (Macaca sylvanus). In this seasonally breeding species – birth season: mid-March to beginning of August – primiparous 4-year-old females gave birth significantly later in the year than older primiparous and multiparous females, respectively. Multiparous females without an infant from the preceding season gave birth significantly earlier than females who had raised an infant. 88.4% of birth intervals were approximately 1 year, 11.6% about 2 years. Infant loss did not influence the length of the interbirth interval, but after the birth of the next surviving infant the interval was significantly longer. The interval following the 1st infant was significantly longer than after subsequent infants. After the birth of daughters primiparous females had markedly longer birth intervals than after the birth of sons. Infant mortality was 9.1%. Neonatal mortality was influenced by rank and parity of the mother and sex of the infant. Allomothering and aggression by older group members are thought to be the main causes of infant mortality. Female reproduction rates were not dependent on rank. High-ranking females, however, bore their 1st infant significantly earlier than low-ranking females. Low-ranking females had more daughters than sons, in high-ranking females the reverse was found. Differences from findings of other species are discussed with regard to differences in social organization and the reproductive strategies resulting from them.

To evaluate the importance of male competition and female mate choice for male mating success in Barbary macaques, focal female observations during the conceptional estrus were conducted in a large semifree-ranging group. Analysis of sexual behaviour included 121.7 h of observation of 19 focal females. In addition, ad libitum recorded male agonistic interactions, occurring in the vicinity of the focal females, were analyzed. Both sexes initiated sexual associations, and females were found almost always in contact (within 2 m) with a male. Most matings took place within 1 min after contact establishment, and the proportion of these quick matings was especially high for subadult males, which mainly "sneaked" copulations during moments of distraction of adult males. Mating contacts were longer than non-mating contacts, and varied in duration from a few seconds to more than 2 hours. Mating contacts with adult males did not differ in length with respect of the initiating sex. Females were considerably more active in terminating than initiating contacts. Females mated, on average, once every 30 min, and had 1-10 different partners (out of 37 sexually mature males) during a 4 h observation session. Females mated with 40-100% of their contact partners. An absence of mating with specific males was due to interference by other males, improper timing of contact, or (temporary) lack of attractivity of the female rather than related with a rejection of these males in almost all cases. Similarly, a highly significant positive correlation between mating frequency of a male and time spent in the vicinity of the focal females revealed that females did not discriminate among potential mates, and, hence, did not exercise mate choice. The majority of matings (71 %) were accumulated by 7 out of the 9 oldest males and additionally 2 young adults. One indicator for sexual competition among males was the peak of male injuries during the mating season. Aggressive interactions between adult and subadult males, indicating a clear-cut dominance of the adults, occurred frequently, while dyadic agonistic interactions between adult males were rare and inconsistent. The available data indicated age-inversed rank relations and were not predictive for mating success. A highly significant positive correlation was, however, found between male mating success and the participation as ally in polyadic agonistic interactions. The oldest males gave and received most support and were rarely victims of coalitions while the reverse was found for young adult males. All males followed an "age rule", after which the older of 2 males was supported during a conflict. Consequently, male power asymmetry in polyadic conflicts ran counter that in dyadic situations, and could change quickly depending on the presence of potential allies. Chances for dyadic solutions of conflicts were rare on the ground where most estrous females and the old males spent their time. Although females did not reject potential mates, they nevertheless influenced male mating success by inciting male competition. Females often tried to contact a new partner after a mating, thereby actively putting both males into conflict. The creation of such encounters was possible only between males with low power asymmetry, and only males which got successfully through these frequent female-initiated tests of their power had a high mating success. Incitation of male competition was discussed as a female mating tactic in species with a high sexual dimorphism. Compared with other macaques, the Barbary macaque belongs to such species.

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ABSTRACT. The association between social rank, mating effort, and reproductive success of male Barbary macaques (Macaca sylvanus) has been evaluated by longterm behavioral observations and subsequent paternity determination via oligonucleotide DNA fingerprinting in a large semifreeranging group. All offspring born between 1985 and 1988 that survived to at least 1 year of age (n = 75) were available for paternity testing. The exclusion of all but one of the potential fathers from paternity was possible in 70 cases (93~ Mating activities were recorded using ad lib. and focal female sampling techniques. The analysis of male mating effort was restricted to the most likely days of conception. Male rank correlated significantly with male mating success in all four breeding seasons and with male reproductive success in three of the four seasons. Mating success and reproductive success also showed a significant correlation, with the exception of one breeding season, in which the proportion of males per fertilizable female was especially high. Poor mating success was almost always associated with poor reproductive success, while good mating success was less predictive for a male's actual reproductive success. This was apparently a consequence of sperm competition, resulting from the promiscuous mating system. Male mating success is not necessarily an unreliable indicator for reproductive success, provided that sufficient sample sizes are available and that conception periods can be determined. Sperm competition and other factors may weaken the association, however.