The 44-year-old rhino, Sudan, and his last two female companions are unable to breed naturally because of issues that include old age, casting the fate of the species even more into doubt.
Kenya is home to the world's last remaining northern white rhino, Sudan.
But at 44 years old, it is feared he won't live much longer, throwing the future of the White Rhinos into question.
Sudan lives at the Ol Pejeta Conservancy, protected by guards around the clock, with two females, Najin and Fatu.
TRT World's Nicole Johnston reports from Kenya.
Poaching on the rise
Poachers have killed more than 7,100 rhinos in Africa over the past decade for their horns.
Rhino poaching has increased in recent years in Namibia, which has one of Africa's biggest populations of the critically endangered black rhino.
Neighbouring South Africa is home to most of the continent's rhinos, including the more numerous white rhino species.
Rhinos have been heavily poached to meet demand for their horns in parts of Asia.
Some consumers believe rhino horn can cure illnesses if ingested in powder form, although there is no evidence that the horn, made of the same substance as human fingernails, has any medicinal value.
Rhino horn is also seen by some buyers as a symbol of status and wealth.