NAIROBI, Kenya-The death of the world's last male northern white rhino, Sudan, doesn't end efforts to save a subspecies of one of the world's most recognizable animals. The focus now turns to his stored semen and that of four other dead rhinos, as well as the perfection of in vitro fertilization techniques and the critical need to keep the remaining two females alive.
Whatever happens, conservationists hope the lessons learned in the endeavor can be applied to other critically endangered species.
The 45-year-old Sudan, who won widespread affection last year with his listing as "The Most Eligible Bachelor in the World" on the Tinder dating app in a fundraising effort, was euthanized on Monday after "age-related complications," researchers said Tuesday.
In his death, the world saw the shadow of extinction approach before their eyes. "Utter tragedy today," British Foreign Secretary Boris Johnson tweeted. "We can't just sit back and watch more species disappear."
The rhino "stole the heart of many with his dignity and strength," said the Ol Pejeta Conservancy in Kenya, where Sudan lived. It said his condition had "worsened significantly," to the point where he was no longer able to stand. His muscles and bones had degenerated and his skin had extensive wounds, including a deep infection on his back right leg.
Euthanasia was "the best option, given the quality of his life had deteriorated to a point where it was unfair to him," chief conservation officer Samuel Mutisya told The Associated Press.
Sudan had been central to the ambitious effort to save the subspecies from extinction after decades of decimation by poachers, along with the two surviving females. One is his 27-year-old offspring, Najin, and the other is her 17-year-old offspring, Fatu.
It is now just a matter of months before eggs are extracted from the two females, said Jan Stejskal, director of international projects at Dvur Kralove Zoo in the Czech Republic, where Sudan lived before coming to Kenya.
Scientists have developed a technique to extract the eggs, using females from the similar southern white rhino subspecies from European zoos, Stejskal said. The genetic material would have to be transferred to a lab in Italy that he said was the only place where embryos of northern white rhinos can be created.
Sudan was the last of his kind to be born in the wild, in the country that is his namesake. He was taken to the Czech zoo and then transferred to Kenya in 2009, along with the only other remaining northern white rhinos, the two females and a male who died in 2014.
Rangers caring for Sudan described him as gentle and, as his condition worsened in recent weeks, expressed sadness over his imminent death.