A four-month old furball kept hard-nosed journalists in Washington DC captive as Bei Bei, the giant panda cub, made his media debut at the Smithsonian's National Zoo on 16 December.

The zoo's Mei Xiang gave birth to the cub in August 2015 – she was already one of the top tourist draws in the US capital.

Sometimes squirming and frisky, Bei Bei appeared unsure with his sudden fame, preferring to huddle, instead, in a bamboo-lined hole in the enclosure, but zoo officials said the little cub was more active than his siblings, often crawling and exploring his surroundings.

"Bei Bei is just a rough and tumble little boy. He is out there, he spends a lot of time out of the den, he seems to want to get up to as much mischief as he can," said Dr Brandie Smith, associate director of animal care at Smithsonian's National Zoo.

At 17.5lbs, Bei Bei is also larger than both his older siblings Bao Bao and Tai Shan were at the same age. "He's actually about four or so pounds heavier than his sister was at the same age, so he's definitely a much larger bear and he's developing a lot faster than his older sister did," giant panda keeper Juan Roriguez said.

A second cub born with Bei Bei died shortly after birth. They were sired by Tian Tian, the zoo's male giant panda, using artificial insemination. Their birth captured international attention since giant pandas are among the world's most endangered species.

Giant pandas are native to China and have a very low reproductive rate, especially in captivity. There are about 300 giant pandas in captivity and some 1,600 in the wild. Bei Bei will make his public debut on 16 January 2016.