Just two weeks after San Diego Zoo Safari Park celebrated the arrival of six southern white rhino from South Africa, their Northern White Rhino, Nola has died. Nola was one of only four of her kind left alive on planet earth.

According to a statement by San Diego Zoo on their Facebook page, Nola's death followed a bacterial infection and other age-related problems. Her death “is a very difficult loss....to her species worldwide.”

When the six southern white rhino arrived at the Zoo on 10 November 2015, they were set to join Nola in the Safari Park.

Researchers are hoping that by using genetics and selective breeding, to breed their own northern white rhino in the next 10 to 15 years.

The strategy to save the northern white rhino is now reliant on the work of geneticists. The San Diego Zoo Blog explains that they have banked “living cells” in order to “preserve the genetic lineage of northern white rhinos.” Nabiré, a hybrid cross between southern and northern white rhinos died in July this year.

Barbara Durrant, a reproductive physiologist at San Diego Zoo said that “The reproductive system of rhinos is very complex…much we do not know”.

The San Diego Zoo has a dedicated mission to bring endangered species “back from the brink of extinction.” The death of Nola hits very hard and around the world, rhino lovers share the pain of the zookeepers and dedicated professionals who cared for Nola.

The death of Nola now means that there is no longer any viable population of the species left in the world. CNN report,“the remaining three are in the Ol Pejeta Conservancy in Kenya.”

These rhinos are heavily guarded by 24-hour armed security and are restricted to a 700-acre enclosure. The last northern white rhinos are protected by teams of trained dogs, a Piper Supercub surveillance aircraft, a multi-range drone, armed and highly trained mobile teams, rhino patrol teams and others who operate both inside and outside of the protected area.

The conservancy has been trying to breed the northern white rhino. In 2012, one female, Najin, was mounted by a male, but tests later revealed that she had not become pregnant.

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