Japan's Only Giant Panda Dies of Old Age

Zookeepers tried but failed to encourage Ling Ling to mate with visiting pandas. Ueno's female panda, Tong Tong, died in 2000.

China has a long tradition of offering pandas reared in its southwestern province of Sichuan as gifts to foreign governments to improve ties.

Giant pandas have helped put themselves on the list of the world's most endangered species because of an apparent lack of interest in sex, which experts have sought to remedy with everything from Viagra to pornographic videos.

Ling Ling, born in Beijing Zoo in 1985, was given to Ueno Zoo in 1992 in exchange for a Japanese-born panda to commemorate the 20th anniversary of the restoration of diplomatic relations between the two countries.

Hu is due to visit Japan from May 6-10 for what will be only the second trip by a Chinese head of state to Tokyo.

Relations between the countries have long been tense, in part due to the legacy of Japanese aggression before World War II.

Related Links:

Jennifer Viegas' blog: Born Animal

Animal Planet

How Stuff Works: Why Is the Birth Rate So Slow for Giant Pandas?

World Wildlife Fund