Energetic pandas kept awake by unseasonably warm weather have been showing off their acrobatic skills at the world's oldest zoo.
Helmut Pechlaner, director of the Schoenbrunn Zoo in Vienna said: "The bears are only young and love climbing the trees, but I've never seen one do a handstand at the top of a tree before.
"Normally they slow down and sleep a lot at this time of year, but it has been so warm in Austria lately that they've been more active than usual."
Female bear Yang Yang and her partner Long Hui were presented to Schoenbrunn Zoo two years ago by the Chinese government following a personal request from Austrian Chancellor Wolfgang Schuessel.
The young pair will stay in the Austrian capital for 10 years to raise awareness of endangered species before returning to their homeland in 2013.
There are only an estimated 1,600 Giant Pandas left in the wild.
The pair become an instant hit in the Alpine republic, quickly becoming one of the most visited attractions at the 18th century zoo.
Yang Yang and Long Hui are also under constant observation by zoo scientists as little is known about the habits of the Giant Panda.
It is hoped the two will mate and return to China as a family group but zoo keepers say that despite their best efforts the pandas are simply much more interested in bamboo than sex.