DAVID GREENE, HOST:
Now to an effort to save a species - it's the northern white rhino. In the entire world, there are only five left. Two are in a zoo in the Czech Republic. The others are in a nature preserve in Kenya.
RICHARD VIGNE: We built a special enclosure of about 600 acres for them. There were two males and two females. Then late last year, one of the males died, leaving Sudan as the only remaining northern white rhino male alive in the world today.
GREENE: That is Richard Vigne. He's head of the Ol Pejeta Conservancy where Sudan lives. The rhinos are guarded around the clock from poachers.
VIGNE: The black market price for rhino horn is now in excess of that for gold. In fact, I think the price is nearing the black market price for cocaine.
GREENE: The Conservancy has resorted to some dramatic steps to protect these rhinos.
VIGNE: We also have removed as best we can their horns as a means to reduce the incentive for people to try to kill them.
GREENE: Of course, Vigne hopes the rhinos will reproduce. But Sudan, the last male, is already 42. And that is extremely old for a rhino.
VIGNE: I think we're beyond the point of expecting natural reproduction. What we need to do now is get involved in artificial methods of reproduction, including what is referred to as in-vitro fertilization.
GREENE: And if embryos do result, they would be implanted in a female of a similar species - the southern white rhino.
VIGNE: It's going to be a long process. It's by no means guaranteed of success. But we feel duty-bound to try to make it happen.
GREENE: Now, it will be a very long process to develop this reproductive technology. And Vigne says any baby rhinos are probably years away. By that point, Sudan and the other rhinos may have already died. But their offspring, born to surrogates, would save the northern white rhino from extinction. Transcript provided by NPR, Copyright NPR.