Sudan, a male rhino at Ol Pejeta Conservancy, died on 19 March aged 45, after months of health issues due to old age.
He was the last male northern white rhino, a subspecies which now only consists of two females, Najin and Fatu, who are his offspring.
The subspecies was considered extinct in the wild by 2008, following poaching for rhino horn and conflict in the Democratic Republic of the Congo.
"We on Ol Pejeta are all saddened by Sudan's death," says Richard Vigne, CEO of Ol Pejeta. "He was a great ambassador for his species and will be remembered for the work he did to raise awareness globally of the plight facing not only rhinos, but also the many thousands of other species facing extinction as a result of unsustainable human activity."
Sperm from Sudan and eggs from Najin and Fatu are being stored in the hope that IVF techniques can be developed that would allow scientists to one day breed a new generation of northern white rhinos.
However, there are concerns over inbreeding and many scientists believe that the subspecies is functionally extinct.
The white rhino species is considered to be Near Threatened on the IUCN Red List and consists of two extant subspecies, the southern white rhino and the northern white rhino.
There are an estimated 20,000 southern white rhinos living in the wild, of which more than 90 per cent are found in South Africa.
The five extant species of rhino:
- white rhino - Near Threatened
- black rhino - Critically Endangered
- Indian rhino - Vulnerable
- Javan rhino - Critically Endangered
- Sumatran rhino - Critically Endangered