Good News For Near-Extinct Northern White Rhino

Sudan was the last of his kind

There is now news that it may be possible to save the near-extinct Northern White Rhino.  A victim of poaching (to satisfy the needs of Asian consumers of rhino horn) the northern white rhino population has been reduced to just two females, which are both unable to breed.

The northern white rhino was once common throughout the north of the African continent, including Uganda, South Sudan, the DRC and Chad.  Illegal hunting to meet demand for rhino horn caused a rapid decline in the wild, and the rhino sub-species was declared extinct on the wild in 2008.

Earlier this year, Sudan, the last male northern white rhino, died at the age of 45. Two females are left - his daughter and granddaughter, who live in Ol Pejeta Conservancy in Kenya, where they are guarded around the clock. However, both have health problems of their own and cannot breed naturally.

The southern white rhino is found in southern Africa, including South Africa, Namibia, and Zimbabwe.  Numbers dropped to a few hundred individuals around a century ago, but conservation efforts led to a recovery. About 20,000 exist in protected areas and private game reserves.

 The white rhino split into two divided populations living in the north and south of Africa around one million years ago.  But an extensive analysis of DNA from living rhinos and museum specimens shows the northern and southern populations mixed and bred at times after this date, perhaps as recently as 14,000 years ago.

Cross breeding using assisted reproductive technology could theoretically be used to rescue the northern white rhino from its current predicament.

Sperm from male northern white rhinos is being kept in frozen storage, but conservationists are divided about how it should be used.

In July, one team took eggs from female southern rhinos - which number around 20,000 in the wild - and fertilised them with frozen sperm from a male northern white rhino, to create hybrid embryos.  The new study suggests this sort of approach might pay off, given that the two rhinos are closer genetically than once thought.

Other options include using frozen tissue from a wider pool of northern white rhinos to generate stem cells that have the capacity to develop into eggs and sperm.  This would avoid diluting the gene pool, but is more challenging to achieve.