The images of Wen Li and her twin sister Ya Li were taken at the Chengdu Giant Panda Research Institute.

They show Wen Li struggling up the side of her playpen, before losing her balance and toppling over the side. Fortunately the panda cub was caught by one of her handlers before hitting the floor.

Wen Li and Ya Li were born on July 19, 2009. Just two other pandas were born at the institute in the same year, compared to 18 born in 2008.

Researches have argued that mothers at the institute were simply too “exhausted” to have any more babies.

The institute was set up 1987 with six pandas rescued from the wild. Just over two decades later it is home to 83 giant pandas, about a third of the total pandas kept in captivity in China.

They are a source of national pride in China and their dwindling numbers have become a countrywide concern. They are the rarest type of bears and, with fewer than 3,000 still in the wild, are considered to be among the world’s most endangered species