Behaviour of ewes (Ovis gmelini musimon x Ovis sp.) during the rut

Abstract

It was tested whether male courtship induces changes in activities in female mouflon (Ovis gmelini musimon x Ovis sp.) due to the promiscuous mating system. For females in the presence of males, we expected a higher involvement in social interactions, reduced time spent feeding, increased time standing/scanning and moving, and a higher rate and level of act transition and diversity. We tested these hypotheses by comparing mouflon ewe activities in mixed-sex, mating (one estrous female with at least one adult male) and female groups during the pre-rut (16-31/Oct.), the rut (01-30/Nov.) and the post-rut (01-15/Dec.). Females devoted more time to feeding and less to standing/scanning from the pre-to the post-rut, in mixed and female groups. At the same time, act transition and diversity decreased in female groups. Females could experience reduced appetite during the oestrus period but ecological factors (better quality and higher abundance of food) may explain these results. Differences between mixed-sex and female groups were found only during the full-rut. Females devoted more time to standing/scanning and less to feeding in mixed-sex groups. Although significant, the percent of time dedicated to feeding and standing/scanning was weakly related to the interaction frequency. So the presence of males seems to have a low incidence on female activities, as seen through the low level of social interactions involving females, and their low behavioural responsiveness. Mating groups were observed only during the pre-and the full-rut. Because of small sample size (N = 8), data from the two periods were mixed in order to compare group types. Data on mating groups suggest that oestrous ewes feed much less, move more, change activity more often and are involved in social interactions more frequently than in mixed-sex and female groups. However, as oestrus lasts only 1-3 days, the energy costs of the rut are thought to be low for females.