Fate of entire subspecies of rhino left to one elderly male

OL PEJETA CONSERVANCY, Kenya — It's not that Sudan didn't want a baby. Researchers had watched the 42-year-old northern white rhinoceros try to mount a female. Rangers had seen him stare across the enclosure at the ladies "admiringly," sharpening his horn as if he was preparing to win them over.

But age had caught up with him. His hind legs were weak. The quality of his sperm was poor. And as the odds dimmed that he would mate successfully, conservationists had to reckon with their own failure.

How had the fate of an entire subspecies of rhinoceros been left to one elderly male?

In just a few decades, a large population of northern white males has been reduced to a single 3,500-pound bull living in a 10-acre enclosure with round-the-clock guards. There are also four females left: two in Kenya and one each in the United States and the Czech Republic. But none is fertile, meaning the population is on the verge of extinction.

Even as the world's wildlife faces increasing threats — a surge in poaching, the loss of native habitats — extinction is still often discussed as an abstraction. It's a word used often to prompt action — something that could happen.

But scientists estimate that hundreds — perhaps thousands — of species are becoming extinct each year. In 2011, the western black rhino was classified as extinct. That same year, a subspecies of the Javan rhino was declared extinct in Vietnam. And barring a scientific breakthrough, the northern white rhino, the second-largest mammal in central Africa, will be gone soon, too.

"It's a massive conservation failure," said Richard Vigne, chief executive of Ol Pejeta Conservancy, the private wildlife refuge where the white rhinos now live.

When Sudan was born in 1972 in what is now South Sudan, there were about a thousand northern white rhinos scattered across central Africa. They were concentrated in countries plagued by war: Sudan, Congo, the Central African Republic. When fighting broke out, the rhinos were also victims, killed for their meat or horns, or sometimes exchanged for money or arms.

Rhinos have long been prized. In 1515, the first rhino bound for Europe was shipped from India to Portugal, then put on a boat headed for Rome as a gift for Pope Leo X. The ship capsized, and the animal died. Albrecht Dürer, the German painter, sketched it from a description, writing under the image that the creature was "almost invulnerable."

Two centuries later, a Dutch trader imported another rhinoceros, named her Clara and toured Europe, slipping her wine and liquor.

"God made it so man can take delight in it," read an advertisement for the traveling rhino.

Part of the rhinos' allure has been their appearance — prehistoric-looking behemoths with loose, wrinkled skin one inch thick. Even baby rhinos look as if they could be a thousand years old, their eyes, like Sudan's, glassy and knowing.

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Sudan got lucky. When he was 3, he was rescued by representatives of the Dvur Králové Zoo in the Czech Republic. He was tranquilized, loaded into a boat that traveled the Nile and then heaved onto a series of trucks, trains and trailers that led to a complex described as "a small Africa in Czechoslovakia."

By then, northern white rhinos were endangered, but extinction loomed far off and seemed preventable with just a modest intervention. That intervention never came.

First, the subspecies was wiped out in the Central African Republic, according to the International Union for Conservation of Nature. Then in Sudan. By the mid-1980s, the situation was dire, but not irreversible, with dozens still living in the wild, particularly in Congo.

The risk "would seem to be potentially controllable," said one research paper published in 1986, called "A Last Chance to Save the Northern White Rhino."

By 2003, there were thought to be about 20 rhinos left in Garamba National Park in Congo. A plan was crafted to move some of them to a conservancy in Kenya. At the last minute, the Congolese government blocked it, claiming that the rhinos were a valuable natural resource.

Within a few years, all the rhinos had been killed, leaving only those left in captivity. Biologists went on missions to some of Africa's most remote corners hoping to discover a northern white that had somehow survived. They found nothing.

The situation continues to worsen, not just for the northern whites but for other rhinos. There were 1,215 rhinos poached in 2014 in South Africa, which has the largest population in the world, compared with 13 poached in 2007.

Rhino horn is now sold for $65,000 per kilogram in Southeast Asia, up from $300 in the 1990s. That's around $30,000 a pound — making it a prize for poachers in Kenya, where the average yearly income is less than $3,000. Even the three northern whites at Ol Pejeta are under threat.

Sudan now has 24-hour protection — a team of caretakers during the day and armed guards at night. His horn was chopped off to deter poachers, although it has begun growing back. Last summer, a few miles from where he sits, poachers broke into Ol Pejeta and shot a female southern white rhino, who eventually died of her wounds. Earlier this month, guards foiled another poaching attempt.

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Sudan's guards and keepers have watched him creep toward senility, trying not to think about what's ahead. Suni, 34, one of the last three northern white males, died in October. A few months later, the other northern white male died in San Diego. In the wild, life expectancy of a rhino is about 35 years. Life in captivity is supposed to be slightly longer.

There was once a plan to mate the last remaining northern whites. Four of them, including Sudan, were flown from the Czech Republic to Kenya in 2009 and driven to Ol Pejeta in two big trucks. The idea was to re-create conditions in the wild that lead to successful conceptions.

"We knew it wasn't sure that it would work, but we thought if we change the environment, it could stimulate a successful mating," said Jan Stejskal, director of communications and international projects at Dvur Králové Zoo.

But after years of trying, scientists accepted their failure. One of the difficulties was that Sudan and Suni were too old, their peak years of fertility long passed. And the females had problems, too. Their legs were weak after years in the zoo. One of them, the youngest and most promising, had a degenerative uterine condition.

Now, the most viable solution is to use the frozen sperm of a northern white to fertilize an extracted egg in a laboratory. The embryo produced would then be implanted in a southern white female, a close relative of the subspecies. It has never been done before with a rhinoceros.

"It's like a rescue operation," Stejskal said. "We have to admit our chances are low."

For his part, Sudan's instincts are largely the same as when he roamed the wild. He marks his territory to alert other males of his presence, unaware that there are none left. He spends his days chasing the shade and wallowing in the mud, albeit a bit more slowly than he once did.

Sometimes he grunts in anger, a grumpy streak that the caretakers say has worsened recently.

"We can watch him getting older, and it's sad for us," said Mohammed Doyo, one of the caretakers.

Last week, a group of schoolchildren was allowed into his enclosure, taking photos of Sudan as he rambled between trees. Near the 8-year-old humans, the rhino looked almost comically large, but he seemed docile, responding to a caretaker's instructions.

"Sudan, stop!" shouted Doyo. And Sudan stopped.

"Sudan, come," he shouted. And Sudan came.

When the kids left, Doyo and Sudan remained alone. The sun was starting to set. Sudan's armed guards were preparing for their shift. The rhino sprayed a tree with urine. He walked between a cluster of acacia trees.

"When people come, we tell them, 'This is the last male,' " Doyo said. "But sometimes it's hard for even me to believe."