The last-surviving male northern white rhinoceros has died from "age-related complications", leaving behind just two females with which conservationists hope can save the species from extinction.
Sudan, who researchers say "stole the heart of many with his dignity and strength", was put to sleep on Monday after his condition "worsened significantly", Kenya's Ol Pejeta Conservancy said.
The famed rhino had been part of an ambitious effort to save the subspecies from extinction (due to years of poaching), with help from the two surviving females – daughter Najin and granddaughter Fatu.
"We are all saddened by Sudan’s death," says Richard Vigne, Ol Pejeta chief executive.
"He was a great ambassador for his species and will be remembered for the work he did to raise awareness of the plight facing not only rhinos but also the many thousands of other species facing extinction as a result of unsustainable human activity."
It is with great sadness that Ol Pejeta Conservancy and the Dvůr Králové Zoo announce that Sudan, the world’s last male northern white rhino, age 45, died at Ol Pejeta Conservancy in Kenya on March 19th, 2018 (yesterday). #SudanForever #TheLoneBachelorGone #Only2Left pic.twitter.com/1ncvmjZTy1— Ol Pejeta (@OlPejeta) March 20, 2018
Sudan, the last male northern white rhino to be born in the wild, was a straight-up celebrity, attracting thousands of visitors after arriving from a Chezch zoo under 24-hour armed protection in 2009.
RIP to the last white rhino male on earth. Human beings are shit.— Lenzman (@thelenzman) March 20, 2018
He was fed a special diet and was also listed as the "most eligible bachelor in the world" on Tinder in a fundraising effort, that raised millions to develop reproductive technologies for the species.
Rangers caring for Sudan described him as a "gentle giant" and, as his condition worsened in recent weeks, expressed sadness over his imminent death.
His death is a "cruel symbol of human disregard for nature," says Jan Stejskal, from Dvur Kralove Zoo in the Czech Republic, "and it saddened everyone who knew him, but we should not give up."
During his final years, Sudan came back to Africa and stole the heart of many with his dignity and strength.— Ol Pejeta (@OlPejeta) March 20, 2018
"It may sound unbelievable, but thanks to the newly developed techniques even Sudan could still have an offspring," he adds.
Before passing, Ol Pejeta Conservancy collected a sample of "genetic material", with hopes it could be used in "future attempts at reproduction through advanced cellular technologies."
Additionally, his genetic material was collected yesterday and provides a hope for future attempts at reproduction of northern white rhinos through advanced cellular technologies.— Ol Pejeta (@OlPejeta) March 20, 2018
Northern white rhinos once roamed Chad, Sudan, Uganda and the Central African Republic - but were particularly vulnerable because of the armed conflicts that swept the region over the decades.
Other rhinos, including the southern white rhino and the black rhino, are also under intense pressure from poachers, who kill them for their horns to supply illegal markets in parts of Asia.