By Paul Steyn
The Great Elephant Census adds Botswana's Okavango Delta to its continent-wide aerial count.
OKAVANGO DELTA, Botswana—"Fifteen elephants right!" ecologist Mike Chase shouts above the roar of the single-engine Cessna. The plane swoops low over the herd of gray bodies as they wade single-file across the floodplain below.
We're flying over the channels and islands on the western periphery of the vast Okavango Delta, as part of the Botswana leg of an Africa-wide project known as the Great Elephant Census.
The yearlong project began in February and encompasses 18 countries—the first pan-African aerial survey of savanna elephants since the 1970s. (Forest elephants, concentrated in central and West Africa, aren't part of the census because they're mostly invisible from the air.)
Funded by Microsoft cofounder Paul G. Allen, the census will fill an urgent need, says Chase, who is founder and lead researcher for the project. "If we don't know how many are left on the continent," Chase asks, "how can we plan for the future? What is the baseline? Where do we focus our attention? Where does donor money need to be allocated?
"The truth is that the current population of elephants in Africa remains unknown," he says. "The last surveys in some areas were done 15 to 20 years ago."
According to a 2007 report, there could be anywhere from 472,000 to 690,000. But some experts believe the number may be as low as 250,000.
Founder of the Botswana-based nonprofit Elephants Without Borders, Chase has spent the past 15 years collecting unprecedented data on the status of elephants and other wildlife in Botswana, identifying cross-border elephant corridors, and discovering new migration routes.
So far, overflights of two of the 18 targeted countries have been completed, and surveys are under way in ten others.
"If we know more, then we have a chance of conserving the elephants," he says. "What we do know is that in 2013 we lost 96 elephants a day in Africa."
We also know, without any doubt, that elephants in most parts of their range are declining.
Botswana: An Elephant Haven
Botswana is a happy exception to that trend. The northern part of the country, encompassing the entire Okavango Delta—an inland delta fed by the waters of the Okavango River, which evaporates in the sands of the Kalahari Desert and never reaches the ocean—has one of the few growing elephant populations left on the continent.
The best recent estimates, widely divergent and based on aerial counts in 2010 and 2012, puts Okavango's elephant numbers at 130,000 and 207,000, respectively.
Whatever the exact number, the patchwork of islands, channels, and floodplains of the Okavango are a seasonal refuge for thousands of elephants and other wildlife. This extraordinary landscape was designated UNESCO's thousandth World Heritage site on June 22, and its new status may make it an even safer haven for elephants in the years to come.
"The Okavango being a World Heritage site is a great benchmark in Botswana's natural history," Chase says. "I think [its World Heritage status] will boost the profile of the Okavango, increase tourism to a place where it's desperately needed, and inevitably I hope it helps with the conservation of this world heritage.
"It's one of the last sanctuaries for wildlife on the continent," he adds. "I'm hoping this survey can bolster the conservation efforts that it needs to safeguard its future." More....