The situation of the northern white rhinoceros is dire; only four rhinos are left. After the death of the only one in Europe, Nabire, who lived at a zoo in the Czech Republic, there remains one at the San Diego Zoo and three more living in the Ol Pejeta Conservancy in Kenya. The San Diego Zoo has one female named Nola, and there are two females and one male in Kenya. None are known to exist in the wild, although a group may have been seen in Sudan in 2009. Like most rhinos, they are hunted for their horns. In 1984, only 14 rhinos were known to be alive.
Many rhino species have been threatened, and the southern white rhino faced similar extinction threats. However, it was placed on restrictions that led to a population of over 20,000 today. With such a limited breeding pool, and with the lack of success breeding them in captivity, the species seems doomed. But is it?
Cloning the species is as of yet not an option. The only hope for the four rhinos left is in-vitro fertilization. While most people are familiar with the use of IVF for infertility in humans, it can also be done in animals. When the Czech rhino died, her remaining ovary was removed and taken to a lab for further research. The San Diego zoo currently has genetic material from a dozen rhinos. If an embryo can be conceived via IVF, the embryo can be planted in a female of another rhino species, such as the southern white rhino. The surrogate mother could then carry the fetus to term. While the theory is sound, it has yet to be tried in an actual rhino.
The San Diego Zoo is known for its conservation efforts. Its biggest accomplishment was saving the California condor. After pollution and hunting had depleted the species to only 22 specimens, the zoo took the remaining birds into captivity. Four eggs found in the wild were hatched there. Today, there are 400 condors, many released to the wild again.
Still, the remaining rhinos face an uphill battle. One species, the western black rhinocerous, went extinct in 2013. Other species that went extinct in the 21st century are the baiji dolphin, golden toad, and the Japanese river otter. However, the condor remains a symbol of what can be done to preserve a species. Let's hope that the same can be done for the four rhinos left.
[Photo via Wikipeda/Jeff Keeton]