The Chongqing Zoo announced this week that Er Shun, a 15-year-old panda, gave birth to a pair of male cubs on July 22 through natural mating after returning from Canada in 2020.
Both twins are in good health, at weights of 420 grams and 257 grams.
It is the second time that Er Shun has had twins. She was artificially inseminated and gave birth to a pair of cubs at the Toronto Zoo in October 2015. Those two cubs, Jia Panpan and Jia Yueyue, whose names mean hope and joy, were the first pair born in Canada. In March 2018, they moved to the Calgary Zoo with their parents, drawing a record number of visitors.
In March this year, Er Shun mated with Qing Qing at the China Conservation and Research Center for Giant Panda in neighboring Sichuan province. Four months later, the pair of cubs was born. The older one weighed 132 grams and the younger weighed 91 grams at birth.
"In the wild, giant pandas usually choose to raise the stronger one after giving birth to twins. The weaker one is ignored or abandoned," said Yin Yanqiang, panda technology chief of the zoo. "It is their strategy to ensure at least one can survive."
Consequently, zookeepers have helped raise the weaker cub in a nursery box. They brought it regularly to the mother for breast milk to ensure it develops normally.
Chongqing Zoo now has 21 giant pandas. It started raising them in the 1960s and began panda breeding in the 1980s. As of Aug 8, female adult pandas at the zoo have given birth to 30 cubs, including 13 sets of twins and one set of triplets.
In March 2013, Da Mao, then a 4-year-old male from the Chengdu Research Base of Giant Panda Breeding in Sichuan province, and Er Shun, a 5-year-old female from the Chongqing Zoo, left China for Canada. They were scheduled to stay 10 years under a conservation agreement between the two countries.
However, because of bamboo supply concerns amid the COVID-19 pandemic, the Calgary Zoo returned the loaned animals ahead of schedule in November 2020.