The expense of housing a panda exhibit is proving a financial burden for the four U.S. zoos that host the rare Chinese bamboo eaters.

But that's not deterring city officials, who continue to pine for the exotic animal - and the $2 million facility it will cost to house one.

The Duke City's plans for a panda exhibit at the Rio Grande Zoo "has always been very unique," said Ray Darnell, director of the Albuquerque Biological Park, which includes the zoo. "It's as cost-effective as any animal."

However, zoo directors in San Diego; Washington, D.C.; Memphis, Tenn; and Atlanta have issued concerns with the Chinese government over the costs associated with hosting the pandas, said Dennis Kelly, president and chief executive of Zoo Atlanta.

The pandas belong to China and the four American zoos have entered into expensive, long-term agreements to house a pair of the animals. Atlanta, for example, pays $10 million over 10 years to China for panda conservation programs, Kelly said.

Those agreements also come with assurances that the zoos will conduct panda research, Kelly said.

But that $10 million doesn't include the expenses associated with maintaining the exhibits. The Atlanta zoo, for example, hired about five people dedicated to supplying the pandas with bamboo, Kelly said.

And while pandas typically are a zoo's largest attraction, the level of attention typically drops after a year.

"They're a huge attraction but they don't necessarily, after the first year or two, pay their way, so to speak," said David Towne, president of the Giant Panda Conservation Foundation and a point man in panda negotiations with the Chinese government. "To some degree, as the newness wears off, even your corporate sponsors start to kind of fade away."

Albuquerque is trying to acquire only one panda from China. The city continues to work on a plan with the San Diego Zoo for 2-year-old Mei Sheng, a male offspring from one of San Diego's pandas.

While the costs associated with bring the panda to Albuquerque haven't yet been negotiated, Darnell believes they'll be significantly lower than the other four zoos.

The most Darnell expects Albuquerque to pay is the one-time $500,000 "baby tax" China imposes on zoos' panda offspring.

Darnell said the Chinese could still propose a higher fee, like $100,000 a year.

"The mayor, who's a horse-trader and a good one, would try to get that lower," he said.

Those negotiations aren't expected to come until May, when the city presents China with a formal proposal.

Officials with the San Diego Zoo declined to comment on their discussions with Albuquerque.

The panda project was at the center of a budget battle last summer when the City Council cut $1.8 million for the exhibit from Mayor Martin Chavez's general obligation bond proposal. Some councilors argued basic infrastructure needs were being overlooked in favor of amenities.

Darnell said $2 million to upgrade an unused, former polar bear exhibit was included in the state's capital outlay request to the state Legislature.

The panda would be in what Darnell called "a mountainous environment" that could be converted into a grizzly bear exhibit should the panda plans fall through, Darnell said.

The exhibit would cost an estimated $387,000 a year to operate, including research costs, bamboo, and the salaries of the panda's keepers and research coordinators, Darnell said.

Darnell hopes construction could begin sometime next fall. Should the Chinese approve of the deal, the exhibit could open in the summer of 2007.

Ultimately, the Chinese government controls the fate of the pandas. Once a panda turns 2 the Chinese consider bringing it back for breeding purposes.

Meanwhile, directors from the four zoos with pandas hope to negotiate more manageable fees with China once their agreements run out, Kelly said. Atlanta has about four years remaining, he said.

"We are committed to, at a minimum, honoring the agreement we have," Kelly said. "If we don't negotiate an agreement that's much more sustainable from our perspective, then we'll choose to not continue the exhibit and study pandas."