Giant Panda Cub Developmental Milestones

August 20, 2016
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Bei Bei being weighed.

Below is an overview of developmental milestones for giant panda cubs and the specific dates Bei Bei (BAY-BAY) reached each milestone.

Aug. 22 to Aug. 24, 2015—White fur begins to come in within 48 hours of birth.

Aug. 28 to Sept. 15, 2015—Bei Bei relies on Mei Xiang (may-SHONG) to regulate his body temperature. (Female giant pandas help newborn cubs stay warm and forego eating and drinking to stay with their cubs. At a certain point, Mei Xiang begins to leave her den to eat and drink. This is a sign that the cub can stay warm on its own for short periods of time. Mei Xiang gradually spends more time away from the den as the cub grows.) 

Aug. 30, 2015—Black markings begin to develop.

Sept. 15, 2015—Black markings are completely in.

Oct. 1, 2015—Eyes are partially open.

Oct. 8, 2015—Eyes are fully open.

Nov. 5, 2015—Ear are canals open.

Nov. 9, 2015—Bei Bei takes his first steps.

Nov. 19, 2015—Bei Bei’s first tooth erupts through the gum line.

Dec. 12, 2015—Bei Bei starts mouthing bamboo. (Giant panda cubs begin tasting bamboo and playing with it, known as “mouthing,” before they start eating significant amounts of it.)

Jan. 15, 2016—Bei Bei eats sweet potato for the first time.

Jan. 23, 2016—Bei Bei climbs up the indoor rockwork for the first time.

Feb. 4, 2016—Bei Bei’s first day outside and his first attempt to climb a tree.


  • Stops nursing
  • Separates from Mei Xiang (estimate at 18 to 24 months of age)
  • Learns adult-training behaviors such as participating in blood draws, cardiac ultrasounds, stepping on a scale by age 2
  • Travels to China by age 4 to participate in the breeding program
  • Sexually matures at 6 years of age

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