ATLANTA, Feb. 11 — Lun Lun and Yang Yang have needs. They require an expensive all-vegetarian diet — 84 pounds a day, each. They are attended by a four-person entourage, and both crave privacy. Would-be divas could take notes.
But the real sticker shock comes from the annual fees that Zoo Atlanta must pay the Chinese government, $2 million a year, essentially to rent a pair of giant pandas. Giant pandas are also on loan to zoos in Washington, San Diego and Memphis.
The financial headache caused by the costly loan obligations to China has driven Dennis W. Kelly, chief executive of Zoo Atlanta, to join with the directors of the three other zoos to negotiate some budgetary breathing room. If no agreement with China can be made, Mr. Kelly said, the zoos may have to return their star attractions.
"If we can't renegotiate, they absolutely will go back," Mr. Kelly said. "Unless there are significant renegotiations, you'll see far fewer pandas in the United States at the end of this current agreement."
The San Diego Zoo's contract with China is the first to expire, in 2008. The last contract, at the Memphis Zoo, ends in 2013.
Mr. Kelly says Lun Lun and Yang Yang, Zoo Atlanta's giant pandas, are draining the zoo's coffers far faster than they can be replenished — even though visitors flock to see them. And when people cannot make it through the gates, self-described pandaholics blog with doe-eyed ardor about the bears or stay glued to the zoos' panda Web cams.
Giant pandas are indisputably popular. Two months ago, the public snapped up 13,000 tickets to see Tai Shan, born at the National Zoo in Washington last July, in just two hours. Later that day the free tickets were being traded on eBay for as much as $200 each.
"People will get up in the middle of the night to see the pandas," said Don Lindburg, head of the office of giant pandas at the San Diego Zoo. "I don't think there is a comparable animal. There isn't the enormity of response that you find with pandas."
But after the first year, crowds dwindle, while the expenses remain high. In fact, a panda's upkeep costs five times more than that of the next most expensive animal, an elephant.
A curator, three full-time keepers and one backup keeper care for Lun Lun and Yang Yang at Zoo Atlanta. A crew of six travels around Georgia six days a week, harvesting bamboo from 400 volunteers who grow it in their backyards. (Zoo Atlanta tried growing its own on a farm, as the Memphis Zoo does, but Lun Lun and Yang Yang turned up their noses.)
"It's crazy," Mr. Kelly said. "These bears, year-round, are some of the most pampered animals on the planet. We measure everything that goes in. We measure everything that goes out."
Then there are the contracts, most lasting 10 years. Because China retains ownership of the pandas, zoos lease each pair for $1 million a year. If cubs are born, the annual fee increases by an average of $600,000. In addition, each zoo has agreed to pay another million or so each year to finance research and conservation projects in the United States and in China. Taken together, Mr. Kelly says, the contracts are worth more than $80 million to the Chinese government.
Mr. Kelly said he hoped China would consider the request to reduce the fees because most other countries pay far less for their pandas. Australia and Thailand, he said, pay about $300,000 each year for theirs. So far, China seems amenable to considering it, he said. Chinese officials did not respond to requests for comment.
"There's a perception in China that U.S. zoos are very rich because when they come over, the zoos are beautiful," said Chuck Brady, the chief executive of the Memphis Zoo.
Zoos say they can break even on pandas, but only for the first few years.
"Year three is your break-even year," Mr. Brady said. The Memphis Zoo expects to lose about $300,000 per year on the pandas it leased in 2003. "After that, attendance drops off, and you start losing vast amounts of money. There is a resurgence in attendance when babies are born."
Because they have had cubs born, the San Diego Zoo and the National Zoo have fared better financially than Zoo Atlanta and the Memphis Zoo, which still have not had luck with their breeding programs.
"The general feeling on the American side is that when the initial negotiations were done 10 years ago, we had very little information on the impact of pandas on zoos," Mr. Brady said. "Now we're stuck with this template."
Apart from foot traffic, pandas also inspire valuable, enthusiastic corporate sponsorships. FedEx, for example, flew Ya Ya and Le Le, the pandas at the Memphis Zoo, to the United States from China in a decorated "Panda Express" plane. The public was able to track the flight on a designated FedEx Web site.
Fujifilm, Home Depot, UPS and others have donated millions to be sponsors of panda exhibits at zoos, hoping to solidify business relationships with China, which regards the animal as a national symbol.
Mr. Kelly said he expected the negotiations to progress slowly.
"They are listening. They are open. They have not responded to anything other than to say that the items that we put on the table are open to discussion," Mr. Kelly said. "They have indicated they think the zoos need to honor their current agreements before we make changes."
In the zoos' favor is that the lease program has generated important reproductive successes for a species that is critically endangered, said David L. Towne, director of the Giant Panda Conservation Foundation. Only 1,500 giant pandas are believed to be left in the wild.
For now, though, zoos with pandas do not inspire the envy they once did. "It was like having a World Series winner in your town," said Mr. Towne, who lives in Seattle. But now, he said, based purely on economics, "I've told my mayor and everyone else that the last thing we want is pandas."