The extremely endangered northern white rhino took one step closer to extinction on Friday, October 17 with the death of the rhino Suni, leaving only one breeding male to represent the entire species.

The Ol Pejeta Conservancy in Kenya, which was Suni’s home, released a statement on Saturday declaring that the 34-year-old rhinoceros had died from natural causes. Most rhinos live for 40 or 50 years and scientists are currently performing an autopsy to determine an exact cause of death.

While the poaching of rhinos is a concern in that part of Africa, Suni was being monitored 24-hours a day – making the possibility Suni died at the hand of a human killer highly unlikely, the conservancy said. Suni did not leave any offspring behind and his death means there are only six known animals left in his species – five of which are female.

The northern white rhinoceros is considered a subspecies of white rhino that got caught up in the political turmoil constantly ravaging south-central Africa. The turmoil led to high levels or poaching and loss of viable habitat.

Stuart Pimm, a conservation ecologist at Duke University in Durham, told National Geographic that the plight of the northern white rhino is emblematic of the struggle faced by other large animals in Africa that become victims of human conflicts.

Pimm noted that the loss of the northern white rhino could have other unforeseen effects.

“It’s not just another charismatic animal—it’s also a species that has a very clear ecological role, and we need to be very worried that we have lost that,” he said.

Even if the last breeding rhino isn’t able to produce offspring, conservationists said they are hopeful that the female northern white rhinos can breed with a related subspecies – the southern white rhinoceros.