Panda Passion Fizzles Again; Zoo Takes Over

SAN DIEGO —  The fickleness of Mother Nature is no match for the advances of science.

Shi Shi, a male giant panda at the San Diego Zoo, has again shown a lack of libido toward his female counterpart. So researchers at the San Diego Zoo decided Wednesday to artificially inseminate Bai Yun rather than pass on another year of panda procreation.

“We feel that this is the responsible thing to do,” said Donald Lindburg, a reproduction behaviorist with the zoo.

Zoo officials sedated Shi Shi to collect semen before implanting it into Bai Yun on Wednesday night, but they won’t know if Bai Yun is pregnant until late July or early August.

Pandas have a delayed implantation physiology that allows their bodies to regulate the best time to give birth. Researchers probably would not be able to detect a heartbeat or fetus until about the last 30 days of the 4 1/2-month pregnancy, Lindburg said.

Female pandas are fertile only one to two days a year. Researchers hoped that the pandas would mate this season after a failed attempt last year.

The two pandas were shipped to the zoo from China in 1996 as part of a 12-year research program on the endangered species.

Bai Yun, a playful 6-year-old female, was apparently all for it, but Shi Shi, a cranky 20-year-old male, was more interested in munching bamboo than courting his partner.

Researchers do not have enough information on panda reproduction to estimate the probability that Bai Yun will become pregnant.

Zoos in Madrid, Spain, and Tokyo have had success with artificially inseminating pandas, but attempts at a zoo in Mexico City have failed several times, Lindburg said.