BRUCE WILLIAMS, THE VICE PRESIDENT for conservation at Fossil Rim Wildlife Center in Glen Rose, had hoped that the worst was over for the facility’s four black rhinoceroses once they were relocated from southern Africa after years of negotiations with the Zimbabwean government. In fact, not much could be worse than the crisis the huge beasts were facing in their native land. In the past twenty years, poachers had stalked the animals so relentlessly that the once-thriving population of tens of thousands had plummeted to a mere three thousand. (That’s the official count. “It’s probably lower than that by now,” says Williams.) But an equally fearsome killer awaited them at the end of their journey to the United States. A blood disorder—hemolytic anemia, which causes red blood cells to burst—was destroying at least 20 percent of the captive animals.

Getting the rhinos out of Zimbabwe turned out to be just half the battle. “To say that the situation is critical would be a huge understatement,” says Williams, who predicts that the black rhinos could be extinct by the turn of the century if efforts to save them fail. Despite the Zimbabwean government’s shoot-to-kill policy against poachers, poaching is still rampant. In Asia, rhino horns have been prized for centuries as a folk remedy and as an aphrodisiac. In the Middle East, daggers hafted with rhino horns have become the ultimate status symbol—the horns alone command a price of $60,000. The dwindling number of rhinos has only fed the demand. To complicate matters, a drought is crushing the already poor country, and Evan Blumer, Fossil Rim’s director of animal health and science, speculates that more people are willing to risk the consequences of helping poachers.

In many ways, Fossil Rim, fifty miles southwest of Fort Worth, is the perfect new home for the rhinos. Says Williams, as he gazes over one of the many spectacular scenic over-looks: “This looks exactly the way I remember Africa.” But only weeks after the Wild-life Center’s four pre-selected and apparently healthy rhinos arrived late last April, one stopped eating. Blumer remembers, “We noticed that her lips were slightly yellow and that even though she seemed interested in food, she couldn’t eat.” Once Blumer and his assistants had anesthetized the wild animal and gotten close enough to check her out, they could see that her mouth was pocked with lesions. “Mouth and skin ulcers are the second biggest problem in black rhinos; the syndrome sometimes occurs with hemolytic anemia,” says Blumer. The veterinarian team began ßooding the rhino with antibiotics (via a very big dart) and hand-feeding her wads of alfalfa. “For a while,” says Blumer, “we thought she was getting better.” But festering lesions spread to her body and began attracting ßies. After that, the downward spiral was intense. Besides the usually fatal anemia, the female had been harboring a dead fetus that was poisoning her system. A two-and-a-half-hour attempt to remove the decomposed fetus failed, and a blood transfusion was determined to be her only chance. When another rhino was anesthetized and blood was drawn, he was found to be in the early stages of hemolytic anemia. The female died while receiving the transfusion. The other rhino died several weeks later. Recalls Blumer: “It was like watching a building burn and trying to put it out with a glass of water. I did nothing for a month and a half except think about black rhinos.”

Meanwhile, another rhinoceros in the relocation program had just died in Florida, and three others died even before leaving Africa. James Jackson, the president of Fossil Rim, is also the president of the International Black Rhino Foundation, which negotiated the relocations with Zimbabwe. He is sure that intentions were good. “No one deliberately sent us sick rhinos,” he says. The rhinos chosen for the program are those that can adapt to the confines of holding pens: At two thousand pounds, a rambunctious boxed rhinoceros isn’t the best passenger on a plane. Jackson thinks that perhaps the more-docile creatures may already have been sick but not displaying their illness. “After all,” says Blumer, “rhinos have spent millions of years evolving not to look sick—otherwise they would be somebody’s lunch.”

Jackson’s idea about the origins of the illness is just one of several that are developing out of the crisis.  Blumer discovered that phosphorus levels in the blood had dropped in the compromised rhinos. “We don’t know yet if this is a cause or a result,” says Blumer. Since phosphorus is vital in the functioning of nerves, blood cells, and muscles, Blumer considered the discovery important enough that he completely altered the diets of the two surviving animals. Until now, all captive rhinos were fed high-calcium, high-bulk alfalfa. As of late August, Blumer’s rhinos went on a high-fiber, high-phosphorus, low-calcium plan.

Tissue samples from the postmortems produced intriguing results too. Blumer’s latest theory is that the real problem may be liver disease. He says, “Research efforts are going like gangbusters now—we are learning a lot.” Researchers still don’t know if hemolytic anemia is the cause or the final stage of a galaxy of ills. But the medical analogies are more obvious to Blumer now than they were a few months ago, and the debilitated rhino population may be a step closer to surviving the onslaughts of man and nature. “If we can crack this code,” says Blumer optimistically, “it will completely turn around the effort to save the rhinoceros.”