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Published on Taipei Times http://www.taipeitimes.com/News/feat/archives/2007/03/06/2003351242 Last hope for vanishing white rhinos The world's most endangered large mammal may yet be saved by human fertility methods
By Robin McKie
This fearsome collection has a benign purpose, however, for Hermes intends to use it to save the world's most endangered large mammal: the northern white rhino, whose breeding population has been wiped out in the wild and consists, in captivity, of just two females in a Czech zoo. A program that includes artificial insemination, in vitro fertilization and sex-selection of embryos is to be launched this year, led by Hermes, a zoologist at Berlin's Leibniz Institute for Zoo and Wildlife Research, and his colleagues Frank Goritz and Thomas Hildebrandt. If this team, working with other groups in several European zoos, succeed, they will have pulled off one of the most extraordinary feats in wildlife conservation. Most experts assume the northern white is doomed and will join the dodo, passenger pigeon, quagga and Tasmanian wolf as victims of the predations of modern humans.
The fate of the northern white is tied to that of its cousin, the southern white. The two are hard to distinguish: the southern has slightly smoother skin, the northern slightly longer legs. Thousands of both subspecies roamed Africa's savannah until game hunters and poachers cut the population of each to around 100 animals. In the 1960s, South Africa launched a major program aimed at preserving the southern white. Guards were sent to protect reserves, and poachers were pursued relentlessly. Today there are more than 11,000 southern white rhinos.
Later this year scientists will attempt the first artificial insemination of either Najin or Fatu at Dvur. "Even if that works, it will still only be a start," said Hermes. As he pointed out, rhinos produce a single calf every two years at best, which greatly limits numbers that these two females might produce. Scientists have a couple of other tricks up their sleeves, however. The first exploits the similarity between the southern and northern white. Researchers are learning how to remove eggs from ageing rhinos, allowing them to build up stocks of northern white eggs, which could then be fertilized. The resulting embryos could be implanted in southern whites, which would act as surrogate mothers for the species.
Scientists are also planning to use separation techniques to split female-producing sperm from the male-producing version. "That way we can ensure we produce only female northern calves. From those we can breed even more northern whites. In the end, we might just save the northern white rhino," said Hermes.
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