Stepping through a moist, tree-covered landscape touched with lady's slipper, carnivorous pitcher plants and Indonesian wax ginger, you soon reach your destination: the tigers.

Berani, a 235-pound male Sumatran tiger, pounces from misty grass into a pool as you watch, grateful for the fence separating the two of you. Meanwhile, his 187-pound mate, Chrissie, sits in a small concrete sleeping stall that Mid-Pacific Institute art students have painted with scenes from Sumatra.

Berani and Chrissie, both born in 1999, came from Fort Wayne Children's Zoo in Indiana to join zoo "cover girl" Djelita last Thanksgiving. The tigers had one litter together in Fort Wayne and, approved for two more litters, will be the first Sumatran tigers to give birth at the Honolulu Zoo.

At a time when many zoos across the nation are phasing out species that don't thrive in their environment, the Honolulu Zoo — with a warm, humid climate similar to that of the Indonesian island of Sumatra — is on the brink of transforming its Sumatran tiger quarters into a major exhibit.

"We are the ideal location to be the model breeding program for this type of tiger," said Keoni Pappas, tiger handler and father figure to the tigers.

Sitting next to 15-year-old Djelita's holding quarters, Pappas passionately talked about the tiger-breeding plan — interrupting occasionally to call to the tigers in an affectionate, social roar.

The cubs will stay with Chrissie for two years, as in the wild, before being sent to other zoos.

Breeding the tigers will advance worldwide conservation efforts, as there are only 500 Sumatran tigers left in the wild. There are 200 Sumatran tigers in captivity, and 60 in U.S. zoos.

Before the two tigers can breed, however, major changes to the exhibit need to be made.

There is only one exhibit space for all three tigers. This creates a problem, because female territories don't overlap. Chrissie and Djelita can never be put together, so they alternate between the exhibit and sleeping stalls.

Once a secondary exhibit is built, each female will have her own space, while Berani will switch back and forth between female territories.

After Chrissie gives birth, Pappas said Berani will be paired with Djelita, since males do not participate in cub rearing.

The zoo is seeking to raise at least $120,000 to cover the minimum cost of building a secondary exhibit at two-thirds the size of the existing space, so that the tigers could all be outside at once.

Pappas said if enough money is raised, the new exhibit could be built a little larger, and night quarters could be created to accommodate the cubs that will be full-grown in only eight months.

A tiger can expect two to six cubs in a litter. Chrissie had three cubs in her first litter, so Pappas expects about the same number next time.

Also on the list of hoped-for improvements: a training facility and weight scale to track the cubs' growth.

The zoo also would like to enlarge the pool and install viewing glass to replace the metal fence.

"So there's the fundraiser goal, and then there's the wish list of what's best for the animals and would bring us up to a world-class exhibit, not only from the public's point of view but for the animals' health and safety and conservation," said Pappas.

Pappas is hopeful that the tigers will receive the same support as Rusti and Violet, the orangutans. Their new habitat, which opened in February, cost $700,000, which came from a variety of sources, including funds raised by the Zoo Society.

The fundraising momentum started with the campaign for Rusti will continue on with the Sumatran tigers.

Humane habitat?

The treatment of zoo animals has been gaining national attention. In a recent Time magazine article, for example, David Hancocks, former director of the Woodland Park Zoo in Seattle, argued that some animals, such as elephants, giraffes, bears and antelope, can't be kept humanely in zoos.

Hancocks, an architect who works in Australia as a planning and design consultant, also said tigers can do fine in captivity, "since even in the wild they spend much of their time sitting around digesting their last meal."

Although a male tiger's territory in the wild is as large as 50 square miles, Pappas said there hasn't been a problem with the tigers in the relatively small exhibits at the Honolulu Zoo.

"That's where the keeper's job comes in, to provide environmental enrichment, to keep them active and alert to their environment, adding new features to their exhibit on occasion so they don't get bored," Pappas said. "We haven't seen any problems with this size of the exhibit with the tigers that we've had for all these years."

Zoogoers who peer through the fence into the tiger habitat may feel they're getting a glimpse of a virtual Sumatra, complete with rainforest mist sprinklers along the top of the fence, logs, trees, a pool and a variety of terrain, from hills with lush vegetation to grassy flats.

During a recent visit, everyone watching the exhibit oohed and ahhed as Chrissie flexed her muscles, then suddenly leapt onto a tree to grab some meat laid out by Pappas.

One wide-eyed little girl turned to her mom with a huge grin on her face and said, "I like tigers." At that moment, public and animal seemed happy — at least the one that got to be outside.

Reach Christine Terada at cterada@honoluluadvertiser.com .