With only two individuals left, the northern white rhino has little chance of surviving extinction unless inter-crossing with the southern white rhino.
The previous only confirmed population of northern white rhino in Garamba National Park in north-eastern Democratic Republic of the Congo is now considered probably extinct. Despite systematic ground surveys over probable range and additional foot patrols and aerial reconnaissance, no live rhinos have been seen since 2006 and no fresh sign since 2007. There have been unconfirmed reports of rhino in southern Sudan, and surveys are planned. The last three potential breeding northern white rhino in captivity in Dvur Kralove Zoo in the Czech Republic have been translocated to a private conservancy in Kenya in the hope this will stimulate their breeding. These animals form the only current confirmed population.
Conservation biologists, Bob Lacy and Kathy Traylor-Holzer, have advised that given the current situation of the northern white rhinoceros and overall conservation objective, a stage has been reached where one doesn’t really have any choice of achieving medium to longer term conservation goals without trying inter-crossing the northern white rhino with southern white rhino so as to preserve some northern genes within breeding populations that can hopefully later resume evolutionary adaptation to wild habitats.
They have advised that even in the total absence of human-caused losses, such as poaching, genetic and demographic modelling of such a small population of inter-related animals shows that the remaining three northern white rhinoceroses are unlikely on their own to form a viable population in the longer term because of the negative effects of the severe inbreeding that would most likely occur, and the high probability of chance demographic events significantly reducing or eliminating the remnant population at some time before it has a chance to grow to safer numbers.
Thus, attempts at only pure breeding of the northern white rhino, alone, under these circumstances seem very likely to fail in the medium to longer term, and are, at best, might only be able to preserve inbred “museum specimens” that would not appropriately represent the original northern white rhino. There can be no guarantee that this last-ditch attempt to conserve adaptive northern white rhino genes will succeed and inter-crossing may end up not being successful.
• Image | © Derrick Story, Some Rights Reserved (CC BY-NC-ND 2.0)
• Sources | (Emslie, 2012)
