Randy Rieches still remembers the day Angalifu came to the Safari Park.
"It was still a shock, even though we knew he had been having some medical issues," Rieches said.
In fact, it was Rieches who brought the rhino here from Europe. It's that bond that makes this so hard.
"It's very, very difficult when you've dedicated your life to saving species, to have something like this happen on your watch," he said.
What makes this passing so devastating is that it was one of only six northern white rhinos left in the world. Now, only four females and one male are alive -- all too old to breed.
"It is definitely the end of this species with normal reproduction possibilities, because all the animals now that are living are post-reproductive," Rieches said.
Over the years rhinos have been decimated by poaching and wars in Africa. In fact, one is killed every eight hours.
"Most rhino species have a 16-month to 17-month gestation. They only have an offspring every three years. So we're actually now losing rhinos faster than we're having them born," Rieches said.
But there is some hope. The zoo has been saving genetic samples of the northern white rhinos, freezing and storing them in their frozen zoo. The hope is when technology advances, they can artificially bring the species back.
"It gives us an opportunity to actually come back and try and reproduce this species, but there's a lot of things to do before we do that," Rieches said.
Until that day, things at Safari Parka won't be quite the same.