At one month old, the twin Giant Panda cubs at the Toronto Zoo are healthy and continuing to grow. The larger of the two cubs now weighs over one kilogram (2.2 lbs.), with the smaller cub not far behind at approximately 750 grams (1.6 lbs.).

Their undercoat (or insulating hair) continues to grow in thicker and whiter, making the areas on their bodies, where the skin is not pigmented black, look much whiter. Although small, they truly look like Giant Pandas now.

Er Shun continues to be a great mother, and the cubs are progressing very well with the coordinated care from mother and zoo staff. However, it is still a very critical time for these little cubs.

Photo Credits: Toronto Zoo

On October 13th Toronto Zoo announced the birth of two Giant Panda cubs, and ZooBorns shared the initial birth announcement and a later update.

The Toronto Zoo has stated that Er Shun and her twin cubs would be living within the private maternity area, inside the Giant Panda House, for approximately four to five months.

Giant Panda mothers are known for only looking after one cub at a time, so keepers are helping raise the twins using a method called ‘twin swapping’. One baby is left with the mother, and the keepers switch the twins every few hours, so each one gets care and milk directly from mom. Since the beginning, Er Shun has been demonstrating excellent maternal instincts, and she began cleaning and cradling the first cub soon after its birth.

As the maternity area of the Giant Panda House is not visible to the public, Toronto Zoo staff have been providing regular updates on the progress of the cubs, via the zoo’s website and social media: http://www.torontozoo.com/GiantPandaCubs/

The Giant Panda (Ailuropoda melanoleuca) is native to only a few mountain ranges in central China, usually at elevations between 5,000 – 10,000 feet. In these cool, misty forests, Giant Pandas forage for bamboo, which comprises 99% of their diet, about 10 to 16 hours a day.

Giant Pandas reach sexual maturity between the ages of four and eight and may be reproductive until age 20. Their gestation period ranges from 95 to 160 days. In about half of their pregnancies, twins are birthed. In the wild, usually only one twin survives, due to the mother selecting the stronger cub to care for and neglecting the weaker.

Only about 1,600 Giant Pandas remain in the wild. About 300 live in zoos and breeding centers around the world, mostly in China. Giant Pandas are listed as “Endangered” by the International Union for Conservation of Nature. Their population is threatened by continued habitat loss, habitat fragmentation, and by a very low birthrate-- both in the wild and in captivity.