A Japanese zoo celebrated the first birth of a baby panda in five years Monday, with the tiny cub small enough to fit in the palm of a human hand. Eleven-year-old mum Shin Shin gave birth just before noon, officials at Tokyo’s Ueno Zoo said in a statement. Pandas are born pink, hairless and weigh around 100 grams - so small it can be difficult to determine their sex. “There have been cases where the sex of a panda has been wrongly determined several years after its birth,” a spokesman said. Shin Shin, who mated with male Ri Ri in February, had earlier given birth in 2012 - the first time at the zoo in 24 years, but the cub died from pneumonia six days later. The mum-to-be delighted huge crowds of well-wishers in Tokyo last month as she sat lazily munching on bamboo and playfully rubbed the husks on her furry belly before being moved into confinement. Giant pandas are painfully bashful animals and clumsy lovers, with males often miscalculating when a female is in the mood for love and frequently baffled by the mechanics of mating, according to experts. In the event the cuddly creatures do feel a romantic spark, sex is frequently over too quickly to impregnate the female, who is only receptive to the proposition for two or three days a year between February and May. Meanwhile, Shin Shin’s happy news has already had an economic impact on local businesses with one Chinese restaurant’s shares soaring by 38 per cent in response. The Totenko chain restaurant already reported a jump last month on news of a possible pregnancy. Its main outlet is near the zoo so a panda baby is expected to boost the numbers of visitors to the area. Considered an endangered species, it is estimated that fewer than 2,000 giant pandas remain in the wild, in three provinces in south-central China.