Chrono-Ethologic Investigations on the Queensland Koala (Phascolarctos cinereus adustus) in Captivity
Cora Richter
Johann Wolfgang Goethe-University Frankfurt On Main Zoological Institute, Frankfurt, Germany
ABSTRACT
The chronologic behavior pattern of a separately kept pair of koalas at the Tiergarten Scho¨ nbrunn (Vienna Zoo) was investigated with regard to how the patterns are distributed over 24hr and the ‘‘zeitgeber’’ (from German; synonym ‘‘entraining agent’’) on which they depend. The data was collected continuously by means of infrared video recording over 3 months, January– March 2003 (2,160hr/animal). Observations were made using the scan-sampling method at 1-min intervals. The total activity and each single behavior are described and analyzed in chrono-ethograms and activity profiles for the first time in this species. The main activity of both koalas occurs between 1:00 AM and 4:00 AM, a continuous sleeping period occurs between 11:00 AM and 3:00 PM (sometimes until 4:00 PM). They become active 1hr before darkness and inactive 1hr before dawn (anticipation). During the day koalas are only awakened and become active due to care measures (feedings/weighing). ‘‘Zeitgeber’’ influencing the koalas’ behavior are feeding and weighing as well as the light/dark change. To influence the koalas’ endogenous rhythm as little as possible, the keepers’ daily routine (time and frequency) has to be modified.