Seasonal changes in the behaviour and circadian rhythms in activity and behaviour of captive koalasPhascolarctos cinereus

Feeding and locomotor activity of one male and three female koalas have been continuously observed for one year at Taronga Zoo, Sydney, Australia. Activity was not restricted to the night, but showed a clear day–night distinction with activity maxima during twilight and following afternoon feeding. Acrophase of activity changed during the year but remained within the first half of the night. The koalas spent between 18 and 20 hours per day resting, and between 2.5 and 4 hours feeding. On average, 7.2±1.90 bouts per day have been observed in the male and 6.5±2.11 bouts in the females. Though there was a clear relation between food introduction and feeding activity, activity pattern and time budget were similar to free-ranging koalas.