Home on the range -- where the rhino, oryx, and zebra play

Except for zoos, the southern white rhinoceros is found only in modest populations roaming parts of South Africa, Zimbabwe, Botswana, and Richard Gold's ranch in Llano, Texas. Mr. Gold is no zoo keeper or trophy hunter interested in a tusk over a teak mantel, but his 1,100-acre, scrub-studded expanse northwest of Austin is part of an unusual experiment to boost the population of the lumbering, leather-skinned mammals.

Thundering about a Texas-size slice of his Sandstone Mountain Ranch are two white rhinos on loan from the Los Angeles Zoo. Another female is soon to join the couple. The idea is that the animals might mate in the more open rangeland (the couple had produced no offspring in 17 years of captivity in Los Angeles). Eventually, progeny could then be shipped off to zoos.

The initiative is, in fact, one of the more innovative gambits being tried by the American Association of Zoological Parks and Aquariums to save endangered and other animal species.

Since 1980, the group has been involved in a modern-day Noah's ark crusade to help save populations of rare animals, mainly through captive breeding programs at zoos, as part of its ``species survival plan.'' One statistic has capsulized the group's concern: Zoo keepers believe that, without such efforts, some 2,000 kinds of mammals, birds, reptiles, and amphibians could go extinct by the middle of the next century.

The survival strategies have ranged from exchange of species among zoos, so as to aid traditional breeding, to exploring such new reproductive technologies as embryo transfer. All are reminders that zoos today are no longer mere users and exhibitors of animals; they have become activist protectors and producers of them as well (whatever the risks and rewards that expanded role entails).

The ranch program, however, is considered one of the more novel programs. ``It could very definitely have a large impact,'' says Elvie Turner Jr., director of the Fort Worth Zoo and current president of the zoological parks association. ``But at present we're keeping a close watch on the model ranch programs.''

The idea is appealingly simple: Enlist ranchers and other big private landowners to help raise and breed rare animals. The zoos provide the animals and technical aid. The ranchers chip in rangeland, food, and whatever fencing or facilities might be needed. In theory, half the offspring go to the ranchers and half to the zoos. But in practice all the animals stay on the range until the herd size is big enough to sustain a certain population.

A chief rationale for the program is simply the lack of space at zoos. All the zoos in the United States would fit neatly inside Brooklyn. Yet close to 300 species are considered threatened today. (The association has picked out 34 for help under the survival plan.) Moreover, often at least 100 animals are needed to sustain a given population and avoid problems of inbreeding.

So far, only three Texas ranches are involved in the experiment. But organizers have received inquiries from many other philanthropists and landowners across the state, as well as from ones in Colorado and Missouri. A similar zoo-without-walls effort was recently launched in Florida, involving a different guardian: A paper company opened up part of its private preserve to four white rhinos.

The other zoos on the range are beginning to breed a few results. J. David Bamberger, for instance, chairman and chief executive of Church's Fried Chicken Inc., now has a herd of 24 scimitar-horned oryxes on his 6,000-acre ranch outside San Antonio. Eight of those rare brown-and-white antelopes (fewer than 600 are believed left in their native habitat in Chad and Niger) were born there.

Mr. Bamberger is no stranger to exotic animals. He raises several kinds of ``Texotics'' -- rare species imported and bred for hunting. But the oryxes aren't for mounting over mantels. ``The primary purpose is survival of the species,'' he says. ``Some of these animals for the first time are smelling trees and walking on grass.''

Another Texas businessman, Tom Mantzell, has reported several births of Grevy's zebras (population 15,000) on his spread outside Fort Worth. And on the Sandstone Mountain Ranch, hands are hoping for the first baby white rhino this month (though not endangered, the southern white rhino has had trouble breeding in zoos).

The ranch concept is considered most conducive to raising ``hoof stock'' animals such as rare antelopes, zebras, and deer. They are better suited to roaming a ranch than, say, a hippo. But how far survival strategies might be carried remains uncertain.

Not all has been harmony between ranchers and zoo keepers. From the start, some keepers doubted whether the independent-minded ranchers had the facilities or fidelity to care for the rare breeds in the freewheeling range environment. A few suspected herds might be opened to hunters. Early on, one zoo keeper told Bamberger flatly that he would not produce ``one live'' birth. His riposte now: ``Mine are as healthy as bears.''

The ranchers, for their part, bristled over some of the management practices of their animal caretaker friends. Now, however, the suspicions seem to be subsiding. ``There is a lot we can learn from ranchers,'' says Dale Tuttle, species coordinator for the oyrx program and director of the Dickerson Park Zoo in Springfield, Mo. ``They have been breeding pedigree livestock for generations.''

Longer-term, though, questions remain. The animals will have to be kept on rangelands for many years to bring herds up to size. What happens if a rancher wants to get out? Ultimately, too, the hunting issue will likely surface: If populations get big enough, they will have to be culled somehow, and some ranchers are interested in selling their stock to zoos or hunters to recoup investments.

``I think the program has a tremendous . . . potential, but there are a lot of problems that need to be resolved,'' says Thomas Foose, conservation coordinator for the zoological parks association.

For now, though, the zoos' ark is expanding, while the ranchers, aside from gaining a possible tax break, are basking in their new role as conservationists. ``The ranchers I've talked to are simply interested in conserving wildlife,'' says Robert Reece, director of the animal habitat at the Kings Island theme park near Cincinnati and coordinator of the white rhino project. A Tuesday column