Image by Ikiwaner
The last surviving male Northern White Rhino died recently. Sudan was 45 which is a good age for a rhino. Indeed were he not the last male of his species his passing would be unremarkable. He is survived only by his daughter and grand daughter. They live on the Ol Pejeta Conservancy in Kenya.
This should serve as a warning, as the subspecies had populations spread across Uganda, Central African Republic, Sudan, Democratic Republic of Congo and Chad. At the end of the 1960s there were thought to be well over 2000 animals left,  but these were all wiped out during the last poaching crisis that occurred in the 1970s and 1980s. There were small numbers (around 10 that survived in the Democratic Republic of Congo) surviving into the early part of the 21st Century.
Garamba National park was the last fully wild home of the Northern White Rhino. In 1984 only 15 individuals survived. At this point an international effort was started to save the species, and ten years later that number had doubled. The number remained relatively stable for a decade, but unfortunately poaching increased again, and as much as half the population was lost in a year. Conservationists on the ground could see what was happening and the government agreed to move the rhinos to Kenya for their safety until the situation recovered. Unfortunately, as often happens, the government changed its mind after protests from ill-informed politicians (much as has halted the translocation of Asiatic Lions to a second home). This, alongside increased insecurity in the area, lead to the suspension of all conservation support for Garamba.
At this point there were eight animals in captivity, six in a zoo in Czech zoo, and these were the population that went to Kent, and from which this deceased male came. There were also 2 animals at San Diego zoo, however these animals are very old and not breeding.
There is stored genetic material that would allow test-tube baby rhinos to be created, and southern white rhinos could carry the young, but with the problems causing the destruction of this subspecies far from solved, it is unlikely that this will be attempted any time soon.