Male and Female Mating Competition in Wolves: Female Suppression Vs. Male Intervention

Abstract

[The social organization of wolves is characterised by strong pairbond associations. Groups may consist of a mating couple and their remaining offspring or of an association of potentially reproductive adults. When a pack consists of several adults, intrasexual mating competition and intersexual partner preference are expected to play an important role in the establishment of sexual relationships. Data from the wild show that as a rule only one female in a pack gives birth. Female suppression is assumed to prevent the other pack members from breeding. Our main interest was to elucidate the proximate behavioural mechanisms by which the socio-sexual relationships are structured in times of the mating season. Special attention was paid to the influence of differences in dominance status and sex on the competitive interactions between pack members. From 1977 to 1985 we studied the social behaviour of wolves in and around the mating season at Burger's Zoo in Arnhem (the Netherlands) by means of detailed observations on two wolf packs. Together with a general rise in frequency of (sexuo-affiliative) interactions we observed an increase in general aggression and in the frequency of interventions during the mating season. Our results reveal certain differences in male and female mating strategies. 1) Separative interventions were observed predominantly in males and were directed against male-female sexual interactions, while such interventions by females were less apparent. 2) Males showed a high frequency of intrasexual aggression but only during the mating season. By contrast, females showed less intrasexual aggression, and instead, showed a high level of intrasexual dominance display, especially the α-female, and they did so both in and outside the mating season. 3) Males tended to intervene in especially those intersexual contacts in which their own preferred female was involved, whereas the intolerance of the α-female was more general, i.e. it was shown with respect to all manifestations of other females. These patterns clearly explain why in free nature wolf social organization tends towards a multi-male uni-female system in which the non-dominant males have little chance of sexual contact, but are generally tolerated as helpers in brood care. In conclusion, male competition was comparatively more context-related while female competition took the form of unprovoked hostility., The social organization of wolves is characterised by strong pairbond associations. Groups may consist of a mating couple and their remaining offspring or of an association of potentially reproductive adults. When a pack consists of several adults, intrasexual mating competition and intersexual partner preference are expected to play an important role in the establishment of sexual relationships. Data from the wild show that as a rule only one female in a pack gives birth. Female suppression is assumed to prevent the other pack members from breeding. Our main interest was to elucidate the proximate behavioural mechanisms by which the socio-sexual relationships are structured in times of the mating season. Special attention was paid to the influence of differences in dominance status and sex on the competitive interactions between pack members. From 1977 to 1985 we studied the social behaviour of wolves in and around the mating season at Burger's Zoo in Arnhem (the Netherlands) by means of detailed observations on two wolf packs. Together with a general rise in frequency of (sexuo-affiliative) interactions we observed an increase in general aggression and in the frequency of interventions during the mating season. Our results reveal certain differences in male and female mating strategies. 1) Separative interventions were observed predominantly in males and were directed against male-female sexual interactions, while such interventions by females were less apparent. 2) Males showed a high frequency of intrasexual aggression but only during the mating season. By contrast, females showed less intrasexual aggression, and instead, showed a high level of intrasexual dominance display, especially the α-female, and they did so both in and outside the mating season. 3) Males tended to intervene in especially those intersexual contacts in which their own preferred female was involved, whereas the intolerance of the α-female was more general, i.e. it was shown with respect to all manifestations of other females. These patterns clearly explain why in free nature wolf social organization tends towards a multi-male uni-female system in which the non-dominant males have little chance of sexual contact, but are generally tolerated as helpers in brood care. In conclusion, male competition was comparatively more context-related while female competition took the form of unprovoked hostility.]