KANSAS CITY, Mo. -- The gift shop at the Kansas City Zoo already is flush with white tiger toys as park officials anticipate the popularity of their special summer exhibit.

A 325-pound tiger with cream-colored fur and somewhat blue-hued eyes will be both the star attraction of a new Asian-themed exhibit and the centerpiece of the zoo's summer marketing campaign.

The 16-year-old cat named Silver will be on exhibit through Oct. 1.

The animal is beautiful, no doubt, but she also is part of a controversy in the conservation community.

Critics say that white tigers are a genetic anomaly and that breeding them does nothing to help efforts to preserve their critically endangered orange cousins.

Defenders say responsible breeding of white tigers does no harm and allows zoos to improve their bottom line -- which is what makes other conservation efforts possible.

"We're producing white tigers simply because they're very popular with the public and they've helped us with the gas and light bill," said Lee Simmons, director of the Henry Doorly Zoo in Omaha, Neb., which has lent Kansas City its summer exhibit.

White tigers are not albinos. They are the result of both parents having a recessive gene for white coloration. The official species survival plan for tigers, a compact among zoos, does not recommend their breeding because they are not pureblooded specimens of any of the five remaining subspecies of tiger.

Natural selection works against white tigers. They are rare in the wild because standing out does not help with catching prey.

But some zoos and private owners deliberately breed them because the public likes to see them. Las Vegas performers Siegfried & Roy enjoyed a cottage industry with them before Roy Horn was severely mauled by a white tiger during a 2003 performance.

Irresponsible breeders may mate close relatives, such as a parent and an offspring, to better the odds of producing white cubs. But that also leads to many birth defects, and animals that cannot be displayed often are discarded, according to the Big Cat Rescue sanctuary in Tampa, Fla.

"From my perspective it is irresponsible, if not reprehensible, because they are bringing these animals into the world purposefully for profit," said Ron Tilson, director of conservation at the Minnesota Zoo and coordinator of the Tiger Species Survival Plan.

But Simmons said zoos breed responsibly by periodically crossing white tigers with orange ones to maintain a healthy gene pool.

"Ron is a good friend, but he's a little bit idealistic," Simmons said of his Minnesota colleague. "I absolutely do not have the slightest little guilt feeling" about breeding or displaying white tigers.

'This zoo needs help'

Kansas City Zoo director Randy Wisthoff knows tigers are severely threatened but says he does not have the facilities or resources to pursue conservation efforts here and abroad that other, larger zoos do.

"Me showing one white tiger here in Kansas City for a summer is not going to make or break the world's tiger population," Wisthoff said.

"Why are we doing it? Because this zoo needs help, and conservation costs money. You've got to start with getting people to come to your zoo."

The Omaha zoo has three white tigers, all of which are currently on loan to other zoos.

The zoo also has a large collection of pureblood tigers of three subspecies and is very active in tiger conservation.

It produced the first test-tube tiger and the first tiger born by artificial insemination.

The Kansas City Zoo's last tiger, a 14-year-old of the Amur subspecies, was euthanized because of old-age complications in 2001.

Wisthoff wants to acquire another orange tiger that is not needed for breeding after the white one leaves.

Wisthoff worked at the Omaha zoo for 25 years under Simmons, and that relationship helped make the white tiger exhibit possible.

Wisthoff said Silver was a wonderful opportunity for the zoo.

"Silver is just a beautiful cat, and the public is going to love her," he said.

The five buildings of Kansas City's old Cat Walk, which has not housed cats since 2003, have been spruced up for an exhibit that also includes several Asian animals new to the zoo, including Francois langur monkeys, tufted deer and wreathed hornbills.

Just about every zoo employee, from the finance office to marketing, pitched in for the in-house construction and landscaping effort in order to save money. Fencing has been lowered to improve the view of the outdoor orangutan exhibit, and benches and picnic tables have been added to the shady walkway.

"We've taken an area that was pretty blighted and rehabbed it by putting a lot of energy into it," Wisthoff said.

The white tiger's roughly 1,000-square-foot space is slightly larger than the outdoor display areas in Omaha and includes shade and a watering hole.

Her diet will consist of 9 pounds of fortified horse meat five days of the week, a knuckle bone to chew on on Sundays and one day of fasting.

On a recent Tuesday, Silver lounged in her exhibit, occasionally yawning and rolling over on her back to expose her soft, creamy belly.

"There is a lot of general excitement just over the fact we've got a tiger back in the zoo," Wisthoff said.