In 2006, researchers undertook an extensive search for Western black rhinos in Cameroon, the place where the species was last sighted. No rhinos were found. Researchers failed to turn up any evidence of their dung, tracks, or signs of feeding. Had the rare subspecies of black rhinoceros gone the way of the dodo? Sadly, yes.
Yesterday, citing the rampant practice of wildlife poaching and a failure to act by Cameroon authorities, the world's largest conservation network declared Africa's Western black rhino officially extinct.
But wait a minute. You just read about black rhinos the other day. There were a whole bunch of them being sedated, blindfolded, and airlifted to safety. And they were upside-down. Yes, of course you saw it — the sight of a 3,000-pound mammal soaring upside-down over a vast African landscape is not a sight you soon forget.
So how can they be extinct?
Well, they can't. But another subspecies of black rhino can. The now-famous flying rhinos belong to one of the four recognized subspecies of black rhinoceros, namely Diceros bicornis minor. And believe it or not, with an estimated population of just 4,240 members, D. b. minor is still the most numerous of the four subspecies.
Of course, the least numerous is now the Western black rhino, known formally as D. b. longipes. In the annual update to its Red List of threatened species, the International Union for Conservation of Nature (IUCN) said the latest assessment of the Western Black Rhino had led it to declare the species extinct.
According to the report, overall numbers of black and white rhinos have actually been on the rise in recent years, due in large part to steadfast conservation efforts. (The helicopter relocation of D. b. minor, for example, was headed up by the World Wildlife Foundation's Black Rhino Range Expansion Project — an organization that funnels all its resources into the protection of D. b. minor, specifically.)
But there are many subspecies, like the Western black rhino, that lack the protection necessary (namely from threats like poaching) to keep their numbers from falling.
"[The Western black rhino] had the misfortune of occurring in places where we simply weren't able to get the necessary security in place," explains Simon Stuart, chair of the IUCN Species Survival Commission.
"You've got to imagine an animal walking around with a gold horn; that's what you're looking at, that's the value and that's why you need incredibly high security."
The IUCN Red List now contains almost 62,000 species of plants and animals, including an estimated 25% of the world's mammals.