Most expensive species in captivity

The most expensive zoo species is the giant panda (Ailuropoda melanoleuca), the entire population of which is indigenous to - and owned by - China alone. Four zoos in the US cities of San Diego, Atlanta, Washington and Memphis, each pay an annual leasing fee of $1 million (then £526,340) to the Chinese Government for a pair of these rare creatures. If cubs are born, and typically twins are, a one-off payment of $600,000 (then £315,800) per offspring must also be made. In addition, a panda's upkeep (including bamboo production and security) makes them five times more costly than elephants - the second most expensive species to keep.

In order to promote business ties to China, the four US zoos also pay up to $2 million (£1,053,000) each to sponsor research and conservation projects in the US and China. With this included, the contracts are worth over $80 million (then £42 million) to the Chinese.

Other countries, such as Thailand and Australia, which also host pandas, pay a lesser annual leasing fee of $300,000 (£157,900); the reason US zoos pay more is because the Chinese Government perceives them to be rich, as well as beautiful. Renegotiations of the terms are expected as individual leasing contracts expire over the next few years (e.g. San Diego in 2008, Memphis in 2013).

As of 2005, international biologists estimated the wild panda population at 1,000-2,000 with 188 in captivity around the world.