I grew up reading Zoobooks, and one of the earlier editions I received I immediately loved more than most. Sure, the dolphin one taught me the word ‘ecology,’ and if I was a zoologist I’d probably study bats or some kind of ungulate, but there is one odd-toed ungulate issue that stood out: the rhinoceros.
At the time, maybe 1998, the most sensitive conservation concerns revolved around the Asian rhinos such as the Javan rhino, Rhinoceros sondaicus, and the Sumatran rhino, Dicerorhinus sumatrensis, although all rhinos struggled to maintain viable populations. In that time the northern white rhino, Ceratotherium simum cottoni, has dwindled to five individuals.
Many online news sources recently have covered the story of Sudan, an elderly 42-year-old that is the last male northern white rhino. Along with these stories are images of Sudan with his 24-hour assigned guards walking alongside the dehorned creature on his 700 acre enclosure at Ol Pejeta Conservancy in central Kenya. At his advanced age he will not likely mate again, so his role in the conservation moral is more symbolic than pragmatic. However, many of the last members of this subspecies have already donated their gametes for future breeding efforts that may involve in vitro fertilization using southern white rhinos as surrogate mothers.
While some may not consider the demise of a subspecies as significant, researchers published an updated analysis on anatomical and genetic differences between the northern and southern variations and concluded they evolved far enough back in time, about one million years, to be regarded as distinct species.
The Dvur Kralove Zoo of the Czech Repulic, where some of Ol Pejeta’s rhinos were shipped from in 2009, spent many years trying to breed the rhinos through artificial insemination without success. Another pair, now lone elder female, at the San Diego Zoo in California did not breed.
As per their reputation, the rhinoceros family declines primarily due to poaching for horns that are sold as ingredients in traditional Asian medicine, often supposed to cure a broad range of ordinary and rare illnesses, even used in love potions. Even though purchasing and selling rhino horn is illegal in China, most continue to do so, often without knowledge that it is illegal. Another market is in Yemen where horns are used as handles for ceremonial daggers.
Considering that each kilogram fetches a price around $65,000 (American), which is more lucrative than similar amounts of “gold and wholesale cocaine” as The Guardian pointed out, the South African government is considering legalizing and regulating the market in hopes of driving down profit in the industry. However, South Africa is not northern white rhino territory, and this subspecies receives little support from the Central African Republic, Chad, Democratic Republic of Congo and South Sudan where human government sits in too much turmoil to invest in conservation.
Other rhino species and subspecies have flirted with extinction. Currently on the west end of Java is the last population of Javan rhinos, numbered at 40 individuals. The Indian rhino almost vanished during the days of British imperialism. The southern white rhino numbered just 20 individuals a century ago. Despite rebounds for the Indian and southern white rhinos, any species surviving from a few dozen individuals will have a small gene pool and be susceptible to the same diseases and have a limited ability to adapt to environmental changes. This is known as the bottleneck effect or inbreeding depression.
The Guardian wrote articles after the last two northern white rhino deaths, so they may continue to publish the morbid countdown.
It is sad that despite the optimistic tones used in children’s books and magazines about wildlife, such as Zoobooks, reality eventually sacrifices our biota. Extinction does not claim just random species that most of the public never hears about, or the ones that are not evolutionarily fit enough to continue, but the charismatic macrofauna that the conservation industry and passionate supporters have aggregated vast amounts of time and finances into so humans are not directly responsible.
Update: While researching on another rhino topic, I came across a news article on Nola, who recently died of bacterial infection, leaving three northern white rhinos left. I thought there were five! So in the six and a half months since writing this, we have lost:
- Nabiré, the last of Dvůr Králové Zoo’s northern white rhinos, died July 2015.
- Nola, the last San Diego Zoo northern white rhino residents, died 23 November 2015.
On the plus side, these animals have names, so it’s even easier to divulge sentiment.