Seasonal oestrous cycle activity of captive female koalas in south-east Queensland
K. BallantyneA,C, A. LisleA, A. MucciB and S. D. JohnstonA
ASchool of Agriculture and Food Science, University of Queensland, Gatton, Qld 4343, Australia
BDreamworld, Coomera, Qld 4209, Australia
This study investigated the seasonality of behavioural oestrus in a captive koala population in south-east Queensland. A total of 33 sexually mature koalas were examined over a 4-year period (2009–12) to determine the possible inﬂuence of temperature, photoperiod and rainfall on the incidence of expression of behavioural oestrus without the confounding effect of lactation or limiting food resource availability. Although signs of behavioural oestrus were detected throughout the year, an obvious seasonality was apparent, with signiﬁcantly fewer females displaying behavioural oestrus in late autumn and winter (May–August) than September to April (P<0.0001). While average monthly photoperiod (P<0.0001) and average monthly temperature (P<0.0001) were signiﬁcantly related to oestrous behaviour, rainfall was not (P>0.05). A better understanding of the seasonality of reproductive function in the female koala will facilitate the use of reproductive management-assisted breeding technology to enable improved genetic management in captive populations.