Nabire, a northern white rhino female bed in captivity, died Monday. Photo: Dvur Kralove Zoo

Nabire, a northern white rhino female bred in captivity, died Monday. Photo: Dvur Kralove Zoo

The northern white rhino inched closer to extinction Monday when a 31-year-old female named Nabire died in a Czech Republic zoo due to complications from a ruptured cyst, leaving only four northern white rhinos in the world.

"It's an indescribable loss," Dvur Kralove Zoo director Premysl Rabas said in a statement on the zoo's website Tuesday. "Nabire was the kindest rhinoceros, which we bred at the zoo.

"It is not just that we were very fond of her, her death is a symbol of the catastrophic decline of rhinos due to a senseless human greed. Her species is on the very brink of extinction."

Sudan is the last northern white rhino male, which is being guarded around the clock at the Ol Pejeta Conservancy in Kenya, along with two females, Najin and her daughter Fatu, according to AFP. The other remaining northern white rhino is Nola, an elderly female living at a zoo in San Diego.

Sudan and two females are guarded round the clock (though not always as closely as in this photo) at the Ol Pejeta Conservancy in Kenya. Photo: Ol Pejeta Conservancy

Sudan and two female northern white rhinos are guarded round the clock (though not always as closely as in this photo) at the Ol Pejeta Conservancy in Kenya. Photo: Ol Pejeta Conservancy

The Ol Pejeta rhinos were shipped from the Czech zoo in 2009 in hopes that the natural environment would encourage breeding, but that hope is said to be fading. Captive breeding and artificial insemination have proven ineffective in preventing the extinction of the species.

Nabire was only the second northern white rhino bred in captivity at the Dvur Kralove Zoo.

The last wild northern white rhino was recorded in Central Africa in 2007, according to the zoo. The species has been decimated by poaching.

Poachers kill rhinos for the horns, prized in Asia for its ancient belief they can reduce fevers and seizures, though it's said be be like biting your fingernails.

Conservationists are about to launch new methods for fighting poaching, including hidden cameras inserted in the horns.

Alas, it appears too late to save the northern white rhino.

More from GrindTV

4 things you forgot you could do in Rocky Mountain National Park

Video of 8-year-old with cerebral palsy finishing triathlon takes Internet by storm

Life-size LEGO camper could break the world record