A group of pandas in the San Diego Zoo got a surprise on 14 November when more than 16 tonnes of artificial snow was blown into their den to keep the animals stimulated. A zoo video shows three-year-old Xiao Liwu sliding in the slush and playing with his new toy, a jungle ball.

Officials from the zoo said snow was important for the pandas as it kept them stimulated and active in a different environment to their natural habitat and allowed them to show their natural behaviours.

The pandas are on loan to the zoo from China. The zoo is collaborating with the Chinese Academy of Sciences in studies of panda behaviour, ecology and genetics in an effort to further knowledge and protect the species.