Subjects and housing

The behavioural study focused on a female (YANG YANG, studbook #514) and a set of twins (male FU BAN, studbook #1026 and female FU FENG, studbook #1027) born at Vienna Zoo in 2016 (Fig 1). The female YANG YANG was born in 2000 in Wolong and was transferred to Vienna in 2003 together with a male giant panda (LONG HUI, studbook #526) of the same age. Until 2016 YANG YANG raised overall 5 cubs (male FU LONG, studbook #685 in 2007, male FU HU, studbook #789 in 2010, male FU BAO, studbook #887 in 2013 and the twins FU FENG and FU BAN in 2016) which were sired by the male LONG HUI in natural mating.

All giant pandas are housed in an exhibit at Vienna Zoo, comprising a 135m² indoor enclosure, an approx. 1000m² outdoor enclosure and 33.5m² off-exhibit rooms. All cubs were born in an artificial denning box, a wooden box located in one of the off-exhibit rooms. The first and the second singleton cub stayed in the denning box throughout the entire observation period of 100 days. The twin cubs were transferred to a hollow tree located in the indoor enclosure by the female 71 and 72 days after parturition. The adult male, and sire of the cubs, was separated from the female and had no contact to the cubs throughout the entire observation period.