Sudan, the last male of his kind, died on March 19, 2018, in Kenya. It’s now curtains for northern white rhinoceroses. His survivors are his daughter Najin and Najin’s daughter, Fatu.
The international media chronicled the poignancy of the 45-year-old’s death at Ol Pejeta Conservancy, a private reserve owned and operated by a Kenyan NGO in a long-term agreement with another NGO, Flora and Fauna International, UK.
Aside: White rhinos are grey. So why are they called white? The Dutch described the animals for their ‘wijde’ (meaning wide) mouths, with which they graze on grass. The Afrikaans word is ‘weit’. Depending on the source, the English name is borrowed from one of these two languages. Black rhinos have pointed mouths to browse on leaves and shoots.
Without a male, only assisted reproductive methods can keep these rhinos going. Genetic and semen samples from Sudan are in cold storage awaiting technological advances and funding. Ol Pejeta set up an account for him on the matchmaking app Tinder, hoping the resulting publicity will raise funds to support IVF and stem cell procedures. Despite these extraordinary efforts and the recent death of Sudan, the northern white rhino was functionally dead a long time ago.
Sudan was probably born in 1972 in Shambe, southern Sudan. Josef Vágner, the then director of Dvůr Králové Zoo in Dvůr Králové nad Labem in former Czechoslovakia led ten expeditions to Africa to collect mammals. On one such safari to Shambe, he captured three-year-old Sudan and five other rhinos. The zoo also imported two more from England, including Nasime, a female caught in Uganda in 1965. Between 1977 and 1992, she gave birth to four calves in captivity, two of them sired by Sudan.
Trouble in the wilderness
Meanwhile, northern white rhinos were in deep trouble in the wild. They may have ranged over much of Africa north of the equator at one time. But by the 1960s, they had become restricted to what we now call South Sudan, Central African Republic (CAR), Democratic Republic of Congo (DRC) and Uganda. By then, Chad had no white rhinos. War came in the way of conducting surveys in many of these reserves. We know nothing of the animals’ fate in DRC. In 1969, Uganda had about 80, but by 1982 there were none.
In 1981, a four-member team wrote a report for IUCN’s African Rhino Specialist Group on the results of aerial surveys of the Shambe region, where Sudan and other northern white rhinos had been captured six year earlier. All they saw was the skeletal remains of seven rhinos. Despite extensive searching, they didn’t see any live ones although 200 to 300 had been alive the previous year. The report acknowledged that counting rhinos from the air is difficult and there may still be some living in the area. “Poaching is widespread and out of control there at present and arms are readily available,” said the authors.
Rhino horn is made of keratin, the same substance in our hair, and finger and toenails. But superstition and traditional medicine imbued it with miraculous properties such as a cure for terminal illnesses. The wealthy displayed it as a status symbol. Fabulous prices and weak governance meant poachers killed thousands of rhinos for their horny appendages.
Garamba National Park in DRC, more than 300 kilometres to the south of Shambe, had more than 1,000 in 1963, which led many to believe this to be the main population of northern white rhinos left. Soon after, rebels from neighbouring Sudan overran the area. In 1966, Kai Curry-Lindahl, a Swedish conservationist based in Nairobi, estimated less than 100 rhinos in the park, and by 1970, this number dropped to between 20 and 30.
In 2000, biologist Kes Hillman-Smith conducted an intensive aerial survey of Garamba. She counted 30 animals in all, including infants. By this time, conservationists believed this was the last population of the northern white rhino.
No wildlife expert has seen northern white rhinos in Garamba after 2008, and conservationists think they are extinct in the wild.
Efforts at captive breeding
As concern for the northern white rhino peaked, captive breeding efforts increased. In 1989, Dvůr Králové Zoo sent three of the original six Shambe rhinos to San Diego Zoo, where they died over the years without producing any progeny. The remaining rhinos were now 20 years old and didn’t reproduce. Perhaps they would in the natural surroundings of their homeland. But both the zoos missed that opportunity in 1995.
“Sadly, an attempt to set up a second wild population in a secure site elsewhere in Africa failed in its attempt as the two zoos with northern white rhinos at the time would not provide any of their rhinos for such an effort,” says Richard Emslie, Scientific Officer of IUCN’s African Rhino Specialist Group. “The then Zaire (later DRC) was only prepared to provide some founder rhinos from Garamba, on the condition the zoos also provided some founder rhinos.”
The economic hardship of Dvůr Králové Zoo after the collapse of the Soviet Union may have also forced its hand. In 2009, it kept two females and sent four to Africa in the hope that they would make rhino infants. The instability of their natural habitat meant the zoo sent the rhinos far outside their range to Ol Pejeta Conservancy in Kenya, more than 1,500 kilometres southeast of Shambe. How were these four individuals going to keep a species alive?
Even in the relative security of the 364-square kilometre reserve, fear of poachers was high. Round the clock, armed security guards watched over each rhino, not unlike celebrities. The animals may not be confined, but they remained captive. As San Diego Zoo lost theirs one by one, media interest in the fate of the species grew. So also did confusion.
Is Sudan the last male of his species or subspecies?
Until 2010, biologists considered the two white rhinos – the northern (Ceratotherium simum cottoni) and southern (Ceratotherium simum simum) – as two subspecies. Colin Groves from the Australian National University and his colleagues argued they are two different species – Ceratotherium simum and Ceratotherium cottoni.
“We compared the cranial morphology (bone structure of the head), dental morphology (the structure of the teeth), body measurements, appearance, behaviour and the genetics of the two groups and came to the conclusion that they were divergent enough to be recognised as two different species,” says Prithiviraj Fernando, an elephant biologist at the Centre for Conservation and Research, Sri Lanka, who collaborated with Groves on the study. Groves died in November 2017. “The genetic analysis of mitochondrial and nuclear DNA demonstrated that the two groups had been genetically separated for over a million years.”
Splitting the white rhino into two species was not popular with many African biologists and conservationists. The IUCN Red List encapsulates the objections. Mordecai Ogada, one of the authors of the book The Big Conservation Lie, is a critic of this taxonomic upheaval. “Splitting species creates an illusion of crisis,” he says. “They point to subtle morphological differences. Geneticists go into very fine resolution to prove difference. They’ve gone overboard. They [rhinos] could be individuals of races but not species. Subspecies is a more acceptable assumption.”
Implications for white rhino conservation
Others like Kees Rookmaaker of the Rhino Resource Center accept the new classification. “Groves is a respected taxonomist who has reviewed many species of mammals, which provides consistency of approach within the class,” says Rookmaaker. “Most taxonomists follow Groves’ approach. Some scientists feel that his taxonomy is unjustified. But when you study the papers, you will find that the genetics are very similar, but the conclusions differ. I think it is unfortunate, especially at a time when the white rhino of Central Africa is at a point of no return.”
As a species, white rhinos are not endangered. At least 20,000 southern whites roam the expanses of southern Africa. If northern white rhinos were a separate species, their situation is extremely dire. If Sudan was the last male of a species, there is no hope for its survival. But if northern white rhinos are a subspecies, the outlook for their future is relatively less severe.
Inbreeding between few individuals would cause maladapted mutations to spread to the detriment of the species. Lots of different individuals maintain genetic diversity that a healthy population needs. The future viability of the northern white rhino depends on interbreeding with southern white rhinos. This is difficult to pull off if they were considered separate species. For instance, Bengal tigers (Panthera tigris tigris) breeding with ones from Sumatra (Panthera tigris sondaica) for conservation purposes would be acceptable since they are both subspecies. But the offspring of tiger and lion has no value for the conservation of either species.
Should taxonomy – the study of classification of life forms – bend to the convenience of conservation?
In 2016, Eric Harley and other geneticists from the University of Cape Town, South Africa, examined the mitochondrial DNA of the two white rhinos once again and concluded they were subspecies. The ancestors of the animals had separated not one million years ago as Groves and his colleagues estimated but more likely between 460,000 and 970,000 years ago. Such inconsistencies are bound to creep in when samples are drawn from few individuals.
The small sample size is not a factor, says Uma Ramakrishnan, a molecular geneticist at the National Centre for Biological Sciences, Bengaluru.
So what is a species? It depends on which of the 10 biological concepts one applies. According to one, if two distinct groups can produce offspring, they are the same species. Another says a geographically restricted population with distinct characters is a different species.
Northern white rhinos produce offspring with southern white rhinos, vindicating the champions of subspecies status. However, polar bears (Ursus maritimus) and grizzly bears (Ursus arctos) are two different species and yet produce fertile young. We don’t know if the hybrid young of white rhinos are fertile because only one was born at Dvůr Králové Zoo, which never bred.
In 2017, Groves and a team of scientists from several institutions defended his previous effort to make the northern white rhino a separate species. They said they weren’t unnecessarily splitting species but correcting past oversight. Taxonomists of the 20th century had lumped several species together. Groves and others pointed to consistent differences in body size, length of bones and vocalisations of the northern and southern white rhinos to make their case. Also, the genetic work that Harley and others had done shows the two rhinos are ‘reciprocally monophyletic’, meaning northern white rhinos are more similar to each other than southern white rhinos.
Emslie suggests looking at the species conundrum differently. “Many conservation geneticists are moving away from talking in terms of subspecies but instead favouring the use of Evolutionary Significant Units (ESUs) and Management Units (MUs),” he says. “In this case, the northern white rhinos and southern white rhinos would be considered separate ESUs and MUs. One usually wouldn’t mix MUs unless there was a good reason to.”
Ramakrishnan concurs that the northern white rhinos may not qualify as a species, but they are a Management Unit. “The genetic differences are low, only around 1 percent. While northern white rhinos are evolutionary and morphologically distinct, the genetic differences are not as high as between other recognised species.” Ramakrishnan wasn’t involved in any of the northern white rhino studies cited here.
With the lack of consensus on the subject, how should we view Sudan’s death? What does it mean for white rhino conservation?
“It is indeed tragic and shameful that this is the second distinct rhino taxa that is going extinct under our watch,” says Fernando, who collaborated with Groves in declaring northern white rhinos a distinct species. “The last Vietnamese Javan rhino [a subspecies of the Javan rhino] was shot and killed by a poacher in 2010.”
“It serves as a warning not to have all one’s eggs in one basket,” says Emslie. “If a second population had been set up two decades ago, there is a very good chance we would still have breeding northern white rhinos in the wild.”
“Sudan’s death is symbolic,” says Elodie Sampere, a spokesperson for Ol Pejeta. “It signifies extinction. If we allow the second largest mammal on the planet to go extinct, what chances do smaller species have? We are currently facing extinction at a faster rate than any other time in human history. We must use Sudan’s death as a wake-up call for the rest of the species.”
Ol Pejeta Conservancy’s press release on Sudan’s death included a call for donations:
The estimated cost of IVF – from the development of the method, to trials, implantation and the creation of a viable breeding herd of northern whites – could be as much as US$ 9 million. Yet this is the hope for preserving an entire subspecies. Ol Pejeta and Dvůr Králové Zoo are asking supporters to donate towards this campaign in memory of Sudan, to help us raise the funds needed before it’s too late.
In 2016, an article in Nature reported that San Diego Zoo had raised $2 million after it had lost all its northern white rhinos.
“They talk like business people,” comments Ogada. “Conservation cannot be a business. Stewardship cannot be a business. This entire sob story is driven by money which is driven by crisis or the illusion of crisis.”
Contested territory in the conservation of African wildlife
Is keeping a subspecies going at this cost worth the effort? Could this money not be put to better use for, say, the Javan rhino or Sumatran rhino?
“First of all, there should be enough funds out there to do both,” says Sampere. “Why do we have to choose? And second, if we manage to bring back the northern white rhinos from the brink of extinction using science, this could mean that we could use the same technology for other species. We feel it is tremendously important to carry on.”
“It is entirely right that our main priority should be to conserve remaining wild rhino in their natural habitats, and such high tech IVF work should not deflect effort and funds away from this,” says Emslie. “However, in this instance, I have been informed that the funding to sponsor the IVF ART [Assisted Reproductive Technology] research work on white rhino is coming from a source that would not be supporting wild field rhino conservation.”
But Ogada is scathing in his dismissal. “There are white rhinos left in South Sudan, and in about a year or two, a ‘saviour’ (most likely Caucasian) will ‘discover’ them to much fanfare and acclamation.”
There is a slim chance of a few northern white rhinos holed up in a remote part. Many of these areas are war zones and no one has explored them for many years. Besides, as conservationists noted more than three decades ago, aerial surveys may not be the best way to find rhinos.
Two years ago, western biologists “discovered” a population of “lost” lions in remote parts of Sudan and Ethiopia. Residents of the area knew of the lions, but until foreign scientists saw them, they were not truly “discovered.” Or take the case of elephants returning to Somalia after 20 years. Such media promotion erasing indigenous experts and knowledge creates resentment among some African conservationists.
“The story is – wildlife in Africa is in danger, and the threat is African people,” says Ogada. “The saviours of wildlife are white. This is the story that sells. There’s a complete diminution of African people. This individual rhino is bigger than a country. One television channel even said Sudan was instrumental in maintaining peace in all of Africa.”
Ogada continues, “Sudan’s death means the end of a particular line of funding, sob story, and source of fame. There are two females left there, but the in vitro fertilisation attempts have nowhere near the gravitas or romance of a single remaining male. Bluntly put, the end of a hoax. For the rest of the world outside Ol Pejeta Conservancy, it is not worth any of the mourning or moaning!”
He goes on to say, “A big chunk of the budget in the conservation sector goes into awareness creation. Basically, opinion manipulation. Ol Pejeta raised millions of dollars into trying to get them to procreate. It’s a strange conservation paradigm that talks about animals in fences and cages. They did very well out of those rhinos.”
Sampere, the spokesperson for Ol Pejeta, says in response to Ogada that “Ol Pejeta never raised millions from the northern white rhinos,” that they “barely raised $200,000. Yet, keeping these animals healthy and alive cost us about $90,000 a year and they have been here since 2009. All the research in the zoo towards IVF is self-funded.”
More than an icon for a species or subspecies driven to extinction, Sudan has come to symbolise contested territory in the conservation of African wildlife.
Janaki Lenin is the author of My Husband and Other Animals. She lives in a forest with snake-man Rom Whitaker and tweets at @janakilenin.