Scientists turn to experimental IVF as last male northern white rhino dies in captivity

After almost a decade of careful safeguarding in a Kenyan conservancy, the last male northern white rhino on Earth has been euthanized following age-related complications. The death of “Sudan” leaves conservationists with advanced IVF treatments as the only hope of saving the subspecies, a process that would be expensive, complex and is as yet unproven.

Sudan the northern white rhino endured a remarkable life, even before he became the last living male of his type. He survived a near-species extinction in the wild during the 1970s, brought about by uncontrolled poaching and conflict in Africa, along with demand for rhino horn in traditional Chinese medicine.

Captured and moved to the Dvůr Králové Zoo in what was then Czechoslovakia, Sudan went on to give birth to daughters Nabiré and Najin, and saw the birth of his granddaughter Fatu. Sudan, Fatu, Najin and another fertile male Suni were moved to the Ol Pejeta Conservancy in Kenya in 2009, in the hope that the climate and healthy grasslands would give the rhinos a greater chance of reproducing.

The rhinos were spotted mating between 2010 and 2012 but to no avail. The death of Suni from natural causes in 2014 then left Sudan alone as the last male northern white rhino, but when vets found that neither of the females Fatu and Najin were able to breed naturally, it was clear the subspecies had a real fight on its hands to survive.
Conservationists have taken some innovative measures to keep the northern white rhino population alive. They tried unsuccessfully to introduce a male southern white rhino to the female northern whites in an effort to at least conserve some of the northern white’s genes, and last year listed Sudan on Tinder as the “most eligible bachelor” to raise funds rhino IVF and rehabilitation. They also brought in drones at Ol Pejeta to ward off poachers.

In December last year, Sudan developed age-related infections and degenerative changes to his muscles and bones. By this Tuesday, his condition had deteriorated so severely that he was unable to stand and was in a great deal of discomfort, so vets made the decision to euthanize him at age 45.

“Sudan was the last northern white rhino that was born in the wild,” said Jan Stejskal, Director of International Projects at Dvůr Králové Zoo. “His death is a cruel symbol of human disregard for nature and it saddened everyone who knew him. But we should not give up. We must take advantage of the unique situation in which cellular technologies are utilized for conservation of critically endangered species. It may sound unbelievable, but thanks to the newly developed techniques even Sudan could still have an offspring. We will be happy for everyone who will help us in our joint effort.”

Efforts to keep the subspecies alive now hinge on the successful development of next-generation artificial reproductive techniques. Scientists are working on a form of IVF where egg cells would be removed from the remaining females, fertilized with semen collected from Sudan and other northern white males, and then inserted into female southern white rhinos who would serve as surrogates.

This has never been achieved before and would come with risk to the rhinos and at a great cost – possibly as much as US$9 million. But it remains the only hope of rescuing the northern white rhino.